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Sample records for jasmonate controls late

  1. Jasmonate

    PubMed Central

    Ramel, Fanny; Ksas, Brigitte; Havaux, Michel

    2013-01-01

    Under stress conditions that bring about excessive absorption of light energy in the chloroplasts, the formation of singlet oxygen (1O2) can be strongly enhanced, triggering programmed cell death. However, the 1O2 signaling pathway can also lead to acclimation to photooxidative stress, when 1O2 is produced in relatively low amounts. This acclimatory response is associated with a strong downregulation of the jasmonate biosynthesis pathway and the maintenance of low jasmonate levels, even under high light stress conditions that normally induce jasmonate synthesis. These findings suggest a central role for this phytohormone in the orientation of the 1O2 signaling pathway toward cell death or acclimation. This conclusion is confirmed here in an Arabidopsis double mutant obtained by crossing the 1O2-overproducing mutant ch1 and the jasmonate-deficient mutant dde2. This double mutant was found to be constitutively resistant to 1O2 stress and to display a strongly stimulated growth rate compared with the single ch1 mutant. However, the involvement of other phytohormones, such as ethylene, cannot be excluded. PMID:24103864

  2. Circadian control of jasmonates and salicylates: the clock role in plant defense.

    PubMed

    Goodspeed, Danielle; Chehab, E Wassim; Covington, Michael F; Braam, Janet

    2013-02-01

    Plants have evolved robust mechanisms to perceive and respond to diverse environmental stimuli.  The plant phytohormones jasmonates and salicylates play key roles in activating biotic stress response pathways. Recent findings demonstrate that basal levels of both jasmonates and salicylates in Arabidopsis are under the control of the circadian clock and that clock-controlled jasmonate accumulation may underlie clock- and jasmonate-dependent enhanced resistance of Arabidopsis to Trichoplusia ni (cabbage looper), a generalist herbivore. Here we summarize these findings and provide further evidence that a functional plant circadian clock is required for optimal herbivore defense in Arabidopsis.  When given a choice to feed on wild-type plants or arrhythmic transgenics, T. ni prefer plants lacking robust circadian rhythms. Altogether these data provide strong evidence for circadian clock enabling anticipation of herbivore attack and thus contributing to overall plant fitness.

  3. Jasmonates: Emerging Players in Controlling Temperature Stress Tolerance.

    PubMed

    Sharma, Manvi; Laxmi, Ashverya

    2015-01-01

    The sedentary life of plants has forced them to live in an environment that is characterized by the presence of numerous challenges in terms of biotic and abiotic stresses. Phytohormones play essential roles in mediating plant physiology and alleviating various environmental perturbations. Jasmonates are a group of oxylipin compounds occurring ubiquitously in the plant kingdom that play pivotal roles in response to developmental and environmental cues. Jasmonates (JAs) have been shown to participate in unison with key factors of other signal transduction pathway, including those involved in response to abiotic stress. Recent findings have furnished large body of information suggesting the role of jasmonates in cold and heat stress. JAs have been shown to regulate C-repeat binding factor (CBF) pathway during cold stress. The interaction between the integrants of JA signaling and components of CBF pathway demonstrates a complex relationship between the two. JAs have also been shown to counteract chilling stress by inducing ROS avoidance enzymes. In addition, several lines of evidence suggest the positive regulation of thermotolerance by JA. The present review provides insights into biosynthesis, signal transduction pathway of jasmonic acid and their role in response to temperature stress.

  4. Jasmonates: Emerging Players in Controlling Temperature Stress Tolerance

    PubMed Central

    Sharma, Manvi; Laxmi, Ashverya

    2016-01-01

    The sedentary life of plants has forced them to live in an environment that is characterized by the presence of numerous challenges in terms of biotic and abiotic stresses. Phytohormones play essential roles in mediating plant physiology and alleviating various environmental perturbations. Jasmonates are a group of oxylipin compounds occurring ubiquitously in the plant kingdom that play pivotal roles in response to developmental and environmental cues. Jasmonates (JAs) have been shown to participate in unison with key factors of other signal transduction pathway, including those involved in response to abiotic stress. Recent findings have furnished large body of information suggesting the role of jasmonates in cold and heat stress. JAs have been shown to regulate C-repeat binding factor (CBF) pathway during cold stress. The interaction between the integrants of JA signaling and components of CBF pathway demonstrates a complex relationship between the two. JAs have also been shown to counteract chilling stress by inducing ROS avoidance enzymes. In addition, several lines of evidence suggest the positive regulation of thermotolerance by JA. The present review provides insights into biosynthesis, signal transduction pathway of jasmonic acid and their role in response to temperature stress. PMID:26779205

  5. Methyl jasmonate induction of cotton: a field test of the 'attract and reward' strategy of conservation biological control.

    PubMed

    Williams, Livy; Rodriguez-Saona, Cesar; Castle Del Conte, Sandra C

    2017-09-01

    Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defence responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively affect herbivore survival, development and fecundity. Indirect responses include increased emission of plant volatiles that influence herbivore and natural enemy behaviour, and production of extrafloral nectar that serves as a food source for natural enemies after their arrival on induced plants. Therefore, the use of elicitors has potential for the study of basic aspects of tritrophic interactions, as well as application in biorational pest control, i.e. an 'attract and reward' strategy. We conducted a field study to investigate the effects of methyl jasmonate, an elicitor of plant defence responses, on three trophic levels: the plant, herbivores and natural enemies. We made exogenous applications of methyl jasmonate to transgenic cotton and measured volatile emission, extrafloral nectar production and plant performance (yield). We also assessed insect abundance, insect performance, and parasitism and predation of brown stink bug, Euschistus servus, eggs in methyl jasmonate-treated and untreated control plots. Application of methyl jasmonate increased emission of volatiles, in particular, (+)-limonene and (3E)-4,8-dimethyl-1,3,7-nonatriene, and production of extrafloral nectar, but not yield, compared with the control treatment. Despite increased volatile and extrafloral nectar production, methyl jasmonate application did not affect plant bug performance, or mortality of E. servus egg masses, and only marginally influenced insect abundance. Mortality of E. servus eggs varied over the course of the study. Overall, methyl jasmonate treatment affected cotton plant-induced responses, but not the insects that inhabit the plants. Our results were probably influenced by reduced natural enemy colonization of cotton from adjacent non-crop habitats

  6. Auxin Controls Arabidopsis Adventitious Root Initiation by Regulating Jasmonic Acid Homeostasis[W

    PubMed Central

    Gutierrez, Laurent; Mongelard, Gaëlle; Floková, Kristýna; Păcurar, Daniel I.; Novák, Ondřej; Staswick, Paul; Kowalczyk, Mariusz; Păcurar, Monica; Demailly, Hervé; Geiss, Gaia; Bellini, Catherine

    2012-01-01

    Vegetative shoot-based propagation of plants, including mass propagation of elite genotypes, is dependent on the development of shoot-borne roots, which are also called adventitious roots. Multiple endogenous and environmental factors control the complex process of adventitious rooting. In the past few years, we have shown that the auxin response factors ARF6 and ARF8, targets of the microRNA miR167, are positive regulators of adventitious rooting, whereas ARF17, a target of miR160, is a negative regulator. We showed that these genes have overlapping expression profiles during adventitious rooting and that they regulate each other’s expression at the transcriptional and posttranscriptional levels by modulating the homeostasis of miR160 and miR167. We demonstrate here that this complex network of transcription factors regulates the expression of three auxin-inducible Gretchen Hagen3 (GH3) genes, GH3.3, GH3.5, and GH3.6, encoding acyl-acid-amido synthetases. We show that these three GH3 genes are required for fine-tuning adventitious root initiation in the Arabidopsis thaliana hypocotyl, and we demonstrate that they act by modulating jasmonic acid homeostasis. We propose a model in which adventitious rooting is an adaptive developmental response involving crosstalk between the auxin and jasmonate regulatory pathways. PMID:22730403

  7. Methyl jasmonate induction of cotton: a field test of the ‘attract and reward’ strategy of conservation biological control

    PubMed Central

    Rodriguez-Saona, Cesar; Castle del Conte, Sandra C

    2017-01-01

    Abstract Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defence responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively affect herbivore survival, development and fecundity. Indirect responses include increased emission of plant volatiles that influence herbivore and natural enemy behaviour, and production of extrafloral nectar that serves as a food source for natural enemies after their arrival on induced plants. Therefore, the use of elicitors has potential for the study of basic aspects of tritrophic interactions, as well as application in biorational pest control, i.e. an ‘attract and reward’ strategy. We conducted a field study to investigate the effects of methyl jasmonate, an elicitor of plant defence responses, on three trophic levels: the plant, herbivores and natural enemies. We made exogenous applications of methyl jasmonate to transgenic cotton and measured volatile emission, extrafloral nectar production and plant performance (yield). We also assessed insect abundance, insect performance, and parasitism and predation of brown stink bug, Euschistus servus, eggs in methyl jasmonate-treated and untreated control plots. Application of methyl jasmonate increased emission of volatiles, in particular, (+)-limonene and (3E)-4,8-dimethyl-1,3,7-nonatriene, and production of extrafloral nectar, but not yield, compared with the control treatment. Despite increased volatile and extrafloral nectar production, methyl jasmonate application did not affect plant bug performance, or mortality of E. servus egg masses, and only marginally influenced insect abundance. Mortality of E. servus eggs varied over the course of the study. Overall, methyl jasmonate treatment affected cotton plant-induced responses, but not the insects that inhabit the plants. Our results were probably influenced by reduced natural enemy colonization of cotton from adjacent non

  8. Control of Carbon Assimilation and Partitioning by Jasmonate: An Accounting of Growth-Defense Tradeoffs.

    PubMed

    Havko, Nathan E; Major, Ian T; Jewell, Jeremy B; Attaran, Elham; Browse, John; Howe, Gregg A

    2016-01-15

    Plant growth is often constrained by the limited availability of resources in the microenvironment. Despite the continuous threat of attack from insect herbivores and pathogens, investment in defense represents a lost opportunity to expand photosynthetic capacity in leaves and absorption of nutrients and water by roots. To mitigate the metabolic expenditure on defense, plants have evolved inducible defense strategies. The plant hormone jasmonate (JA) is a key regulator of many inducible defenses. Synthesis of JA in response to perceived danger leads to the deployment of a variety of defensive structures and compounds, along with a potent inhibition of growth. Genetic studies have established an important role for JA in mediating tradeoffs between growth and defense. However, several gaps remain in understanding of how JA signaling inhibits growth, either through direct transcriptional control of JA-response genes or crosstalk with other signaling pathways. Here, we highlight recent progress in uncovering the role of JA in controlling growth-defense balance and its relationship to resource acquisition and allocation. We also discuss tradeoffs in the context of the ability of JA to promote increased leaf mass per area (LMA), which is a key indicator of leaf construction costs and leaf life span.

  9. Control of Carbon Assimilation and Partitioning by Jasmonate: An Accounting of Growth–Defense Tradeoffs

    PubMed Central

    Havko, Nathan E.; Major, Ian T.; Jewell, Jeremy B.; Attaran, Elham; Browse, John; Howe, Gregg A.

    2016-01-01

    Plant growth is often constrained by the limited availability of resources in the microenvironment. Despite the continuous threat of attack from insect herbivores and pathogens, investment in defense represents a lost opportunity to expand photosynthetic capacity in leaves and absorption of nutrients and water by roots. To mitigate the metabolic expenditure on defense, plants have evolved inducible defense strategies. The plant hormone jasmonate (JA) is a key regulator of many inducible defenses. Synthesis of JA in response to perceived danger leads to the deployment of a variety of defensive structures and compounds, along with a potent inhibition of growth. Genetic studies have established an important role for JA in mediating tradeoffs between growth and defense. However, several gaps remain in understanding of how JA signaling inhibits growth, either through direct transcriptional control of JA-response genes or crosstalk with other signaling pathways. Here, we highlight recent progress in uncovering the role of JA in controlling growth-defense balance and its relationship to resource acquisition and allocation. We also discuss tradeoffs in the context of the ability of JA to promote increased leaf mass per area (LMA), which is a key indicator of leaf construction costs and leaf life span. PMID:27135227

  10. Auxin controls Arabidopsis anther dehiscence by regulating endothecium lignification and jasmonic acid biosynthesis.

    PubMed

    Cecchetti, Valentina; Altamura, Maria Maddalena; Brunetti, Patrizia; Petrocelli, Valentina; Falasca, Giuseppina; Ljung, Karin; Costantino, Paolo; Cardarelli, Maura

    2013-05-01

    It has been suggested that, in Arabidopsis, auxin controls the timing of anther dehiscence, possibly by preventing premature endothecium lignification. We show here that auxin content in anthers peaks before the beginning of dehiscence and decreases when endothecium lignification occurs. We show that, in the auxin-perception mutants afb1-3 and tir1 afb2 afb3, endothecium lignification and anther dehiscence occur earlier than wild-type, and the gene encoding the transcription factor MYB26, which is required for endothecium lignification, is over-expressed specifically at early stages; in agreement, MYB26 expression is reduced in naphthalene acetic acid-treated anthers, and afb1 myb26 double mutants show no endothecial lignification, suggesting that auxin acts through MYB26. As jasmonic acid (JA) controls anther dehiscence, we analysed how auxin and JA interact. In the JA-defective opr3 mutant, indehiscent anthers show normal timing of endothecium lignification, suggesting that JA does not control this event. We show that expression of the OPR3 and DAD1 JA biosynthetic genes is enhanced in afb1-3 and tir1 afb2 afb3 flower buds, but is reduced in naphthalene acetic acid-treated flower buds, suggesting that auxin negatively regulates JA biosynthesis. The double mutant afb1 opr3 shows premature endothecium lignification, as in afb1-3, and indehiscent anthers due to lack of JA, which is required for stomium opening. By treating afb1 opr3 and opr3 inflorescences with JA, we show that a high JA content and precocious endothecium lignification both contribute to induction of early anther dehiscence. We propose that auxin controls anther dehiscence timing by negatively regulating two key events: endothecium lignification via MYB26, and stomium opening via the control of JA biosynthesis. © 2013 The Authors The Plant Journal © 2013 Blackwell Publishing Ltd.

  11. Ecological modulation of plant defense via phytochrome control of jasmonate sensitivity

    PubMed Central

    Moreno, Javier E.; Tao, Yi; Chory, Joanne; Ballaré, Carlos L.

    2009-01-01

    For plants, the tradeoff between resource investment in defense and increased growth to out-compete neighbors creates an allocation dilemma. How plants resolve this dilemma, at the mechanistic level, is unclear. We found that Arabidopsis plants produced an attenuated defense phenotype under conditions of crowding and when exposed to far-red (FR) radiation, a light signal that plants use to detect the proximity of neighbors via the photoreceptor phytochrome. This phenotype was detectable through standard bioassays that measured the growth of Spodoptera frugiperda caterpillars. Two possible explanations for the effect of FR are: (i) a simple by-product of the diversion of resources to competition, and (ii) a specific effect of phytochrome on defense signaling. The first possibility was ruled out by the fact that the auxin-deficient sav3 mutant, which fails to induce growth responses to FR, still responded to FR with an attenuated defense phenotype. In support of the second hypothesis, we found that phytochrome inactivation by FR caused a strong reduction of plant sensitivity to jasmonates, which are key regulators of plant immunity. The effects of FR on jasmonate sensitivity were restricted to certain elements of the pathway. Supporting the idea that the FR effects on jasmonate signaling are functionally significant, we found that FR failed to increase tissue quality in jar1, a mutant impaired in jasmonate response. We conclude that the plant modulates its investment in defense as a function of the perceived risk of competition, and that this modulation is effected by phytochrome via selective desensitization to jasmonates. PMID:19251652

  12. Jasmonates during senescence

    PubMed Central

    Seltmann, Martin A; Hussels, Wiebke

    2010-01-01

    Jasmonic acid and derivatives are oxylipin signaling compounds derived from linolenic acid. Jasmonates accumulate during natural and dark-induced senescence but the increase in these compounds is not essential for the initiation or progression of these senescence processes. Here we report that during natural and dark-induced senescence the increase in jasmonate levels does not trigger jasmonate signaling. Furthermore we provide evidence that jasmonate production might result from membrane turnover during dark-induced senescence. PMID:21057217

  13. JAZing up jasmonate signaling.

    PubMed

    Staswick, Paul E

    2008-02-01

    Recent discoveries show that jasmonate ZIM-domain (JAZ) transcriptional repressors are key regulators of jasmonate hormonal response. Jasmonate promotes interaction between JAZ proteins and the SCF(COI1) ubiquitin ligase, leading to JAZ degradation via the 26S proteasome in Arabidopsis thaliana. Elimination of JAZ repressors then frees the MYC2 transcription factor to stimulate jasmonate-dependent gene expression. Although jasmonic acid and methyl jasmonate were thought to be key regulators of jasmonate responses, they were ineffective in promoting SCF(COI1)-JAZ interaction and it is the isoleucine conjugate of jasmonic acid that acts in this signal transduction pathway. The discovery of JAZ transcriptional regulators greatly advances our understanding of how jasmonate signaling regulates plant growth and response to the environment.

  14. Negative feedback control of jasmonate signaling by an alternative splice variant of JAZ10.

    PubMed

    Moreno, Javier E; Shyu, Christine; Campos, Marcelo L; Patel, Lalita C; Chung, Hoo Sun; Yao, Jian; He, Sheng Yang; Howe, Gregg A

    2013-06-01

    The plant hormone jasmonate (JA) activates gene expression by promoting ubiquitin-dependent degradation of jasmonate ZIM domain (JAZ) transcriptional repressor proteins. A key feature of all JAZ proteins is the highly conserved Jas motif, which mediates both JAZ degradation and JAZ binding to the transcription factor MYC2. Rapid expression of JAZ genes in response to JA is thought to attenuate JA responses, but little is known about the mechanisms by which newly synthesized JAZ proteins exert repression in the presence of the hormone. Here, we show in Arabidopsis (Arabidopsis thaliana) that desensitization to JA is mediated by an alternative splice variant (JAZ10.4) of JAZ10 that lacks the Jas motif. Unbiased protein-protein interaction screens identified three related basic helix-loop-helix transcription factors (MYC2, MYC3, and MYC4) and the corepressor NINJA as JAZ10.4-binding partners. We show that the amino-terminal region of JAZ10.4 contains a cryptic MYC2-binding site that resembles the Jas motif and that the ZIM motif of JAZ10.4 functions as a transferable repressor domain whose activity is associated with the recruitment of NINJA. Functional studies showed that the expression of JAZ10.4 from the native JAZ10 promoter complemented the JA-hypersensitive phenotype of a jaz10 mutant. Moreover, treatment of these complemented lines with JA resulted in the rapid accumulation of JAZ10.4 protein. Our results provide an explanation for how the unique domain architecture of JAZ10.4 links transcription factors to a corepressor complex and suggest how JA-induced transcription and alternative splicing of JAZ10 premessenger RNA creates a regulatory circuit to attenuate JA responses.

  15. Metabolic Fate of Jasmonates in Tobacco Bright Yellow-2 Cells1

    PubMed Central

    Świątek, Agnieszka; Dongen, Walter Van; Esmans, Eddy L.; Onckelen, Harry Van

    2004-01-01

    Jasmonic acid and methyl jasmonate play an essential role in plant defense responses and pollen development. Their levels are temporarily and spatially controlled in plant tissue. However, whereas jasmonate biosynthesis is well studied, metabolic pathways downstream of jasmonic acid are less understood. We studied the uptake and metabolism of jasmonic acid and methyl jasmonate in tobacco (Nicotiana tabacum) Bright Yellow-2 suspension culture. We found that upon uptake, jasmonic acid was metabolized to its Glc and gentiobiose esters, and hydroxylation at C-11 or C-12 occurred. Free hydroxylated jasmonates were the preferential fraction of the culture medium. Upon hydrolysis of methyl jasmonate to jasmonic acid, a similar set of conversions occurs. In contrast to jasmonic acid, none of its derivatives interfere with the G2/M transition in synchronized tobacco Bright Yellow-2 cells. PMID:15133155

  16. Red/Far Red Light Controls Arbuscular Mycorrhizal Colonization via Jasmonic Acid and Strigolactone Signaling.

    PubMed

    Nagata, Maki; Yamamoto, Naoya; Shigeyama, Tamaki; Terasawa, Yohei; Anai, Toyoaki; Sakai, Tatsuya; Inada, Sayaka; Arima, Susumu; Hashiguchi, Masatsugu; Akashi, Ryo; Nakayama, Hideyuki; Ueno, Daisuke; Hirsch, Ann M; Suzuki, Akihiro

    2015-11-01

    Establishment of a nitrogen-fixing symbiosis between legumes and rhizobia not only requires sufficient photosynthate, but also the sensing of the ratio of red to far red (R/FR) light. Here, we show that R/FR light sensing also positively influences the arbuscular mycorrhizal (AM) symbiosis of a legume and a non-legume through jasmonic acid (JA) and strigolactone (SL) signaling. The level of AM colonization in high R/FR light-grown tomato and Lotus japonicus significantly increased compared with that determined for low R/FR light-grown plants. Transcripts for JA-related genes were also elevated under high R/FR conditions. The root exudates derived from high R/FR light-grown plants contained more (+)-5-deoxystrigol, an AM-fungal hyphal branching inducer, than those from low R/FR light-grown plants. In summary, high R/FR light changes not only the levels of JA and SL synthesis, but also the composition of plant root exudates released into the rhizosphere, in this way augmenting the AM symbiosis.

  17. [Jasmonate biosynthesis--the latest discoveries].

    PubMed

    Wilmowicz, Emilia; Frankowski, Kamil; Sidłowska, Magdalena; Kućko, Agata; Kesy, Jacek; Gasiorowski, Adam; Glazińska, Paulina; Kopcewicz, Jan

    2012-01-01

    Jasmonates are plant hormones involved in many growth and development processes. They also participate in plant defense responses. Current progress in the study on biosynthesis and signaling of jasmonates has contributed to the understanding of the mechanisms regulating concentration of these hormones in the cell. Sustaining a proper level of jasmonates allow the plant to respond appropriately to changing conditions. It is possible due to the large number of enzymes and genes involved in biosynthesis of these hormones as well as multilevel control of their expression.

  18. A broad-spectrum, efficient and nontransgenic approach to control plant viruses by application of salicylic acid and jasmonic acid.

    PubMed

    Shang, Jing; Xi, De-Hui; Xu, Fei; Wang, Shao-Dong; Cao, Sen; Xu, Mo-Yun; Zhao, Ping-Ping; Wang, Jian-Hui; Jia, Shu-Dan; Zhang, Zhong-Wei; Yuan, Shu; Lin, Hong-Hui

    2011-02-01

    Plant viruses cause many diseases that lead to significant economic losses. However, most of the approaches to control plant viruses, including transgenic processes or drugs are plant-species-limited or virus-species-limited, and not very effective. We introduce an application of jasmonic acid (JA) and salicylic acid (SA), a broad-spectrum, efficient and nontransgenic method, to improve plant resistance to RNA viruses. Applying 0.06 mM JA and then 0.1 mM SA 24 h later, enhanced resistance to Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV) and Turnip crinkle virus (TCV) in Arabidopsis, tobacco, tomato and hot pepper. The inhibition efficiency to virus replication usually achieved up to 80-90%. The putative molecular mechanism was investigated. Some possible factors affecting the synergism of JA and SA have been defined, including WRKY53, WRKY70, PDF1.2, MPK4, MPK2, MPK3, MPK5, MPK12, MPK14, MKK1, MKK2, and MKK6. All genes involving in the synergism of JA and SA were investigated. This approach is safe to human beings and environmentally friendly and shows potential as a strong tool for crop protection against plant viruses.

  19. Control of storage rot by induction of plant defense mechanisms using jasmonic acid and salicylic acid

    USDA-ARS?s Scientific Manuscript database

    Storage rots contribute to sugarbeet postharvest losses by consuming sucrose and producing carbohydrate impurities that increase sugar loss to molasses. Presently, storage rots are controlled by cooling storage piles. This method of control, however, requires favorable weather conditions for stora...

  20. Jasmonic acid and its precursor 12-oxophytodienoic acid control different aspects of constitutive and induced herbivore defenses in tomato.

    PubMed

    Bosch, Marko; Wright, Louwrance P; Gershenzon, Jonathan; Wasternack, Claus; Hause, Bettina; Schaller, Andreas; Stintzi, Annick

    2014-09-01

    The jasmonate family of growth regulators includes the isoleucine (Ile) conjugate of jasmonic acid (JA-Ile) and its biosynthetic precursor 12-oxophytodienoic acid (OPDA) as signaling molecules. To assess the relative contribution of JA/JA-Ile and OPDA to insect resistance in tomato (Solanum lycopersicum), we silenced the expression of OPDA reductase3 (OPR3) by RNA interference (RNAi). Consistent with a block in the biosynthetic pathway downstream of OPDA, OPR3-RNAi plants contained wild-type levels of OPDA but failed to accumulate JA or JA-Ile after wounding. JA/JA-Ile deficiency in OPR3-RNAi plants resulted in reduced trichome formation and impaired monoterpene and sesquiterpene production. The loss of these JA/JA-Ile -dependent defense traits rendered them more attractive to the specialist herbivore Manduca sexta with respect to feeding and oviposition. Oviposition preference resulted from reduced levels of repellant monoterpenes and sesquiterpenes. Feeding preference, on the other hand, was caused by increased production of cis-3-hexenal acting as a feeding stimulant for M. sexta larvae in OPR3-RNAi plants. Despite impaired constitutive defenses and increased palatability of OPR3-RNAi leaves, larval development was indistinguishable on OPR3-RNAi and wild-type plants, and was much delayed compared with development on the jasmonic acid-insensitive1 (jai1) mutant. Apparently, signaling through JAI1, the tomato ortholog of the ubiquitin ligase CORONATINE INSENSITIVE1 in Arabidopsis (Arabidopsis thaliana), is required for defense, whereas the conversion of OPDA to JA/JA-Ile is not. Comparing the signaling activities of OPDA and JA/JA-Ile, we found that OPDA can substitute for JA/JA-Ile in the local induction of defense gene expression, but the production of JA/JA-Ile is required for a systemic response. © 2014 American Society of Plant Biologists. All Rights Reserved.

  1. Negative Feedback Control of Jasmonate Signaling by an Alternative Splice Variant of JAZ101[C][W][OA

    PubMed Central

    Moreno, Javier E.; Shyu, Christine; Campos, Marcelo L.; Patel, Lalita C.; Chung, Hoo Sun; Yao, Jian; He, Sheng Yang; Howe, Gregg A.

    2013-01-01

    The plant hormone jasmonate (JA) activates gene expression by promoting ubiquitin-dependent degradation of jasmonate ZIM domain (JAZ) transcriptional repressor proteins. A key feature of all JAZ proteins is the highly conserved Jas motif, which mediates both JAZ degradation and JAZ binding to the transcription factor MYC2. Rapid expression of JAZ genes in response to JA is thought to attenuate JA responses, but little is known about the mechanisms by which newly synthesized JAZ proteins exert repression in the presence of the hormone. Here, we show in Arabidopsis (Arabidopsis thaliana) that desensitization to JA is mediated by an alternative splice variant (JAZ10.4) of JAZ10 that lacks the Jas motif. Unbiased protein-protein interaction screens identified three related basic helix-loop-helix transcription factors (MYC2, MYC3, and MYC4) and the corepressor NINJA as JAZ10.4-binding partners. We show that the amino-terminal region of JAZ10.4 contains a cryptic MYC2-binding site that resembles the Jas motif and that the ZIM motif of JAZ10.4 functions as a transferable repressor domain whose activity is associated with the recruitment of NINJA. Functional studies showed that the expression of JAZ10.4 from the native JAZ10 promoter complemented the JA-hypersensitive phenotype of a jaz10 mutant. Moreover, treatment of these complemented lines with JA resulted in the rapid accumulation of JAZ10.4 protein. Our results provide an explanation for how the unique domain architecture of JAZ10.4 links transcription factors to a corepressor complex and suggest how JA-induced transcription and alternative splicing of JAZ10 premessenger RNA creates a regulatory circuit to attenuate JA responses. PMID:23632853

  2. Phenotyping jasmonate regulation of senescence.

    PubMed

    Seltmann, Martin A; Berger, Susanne

    2013-01-01

    Osmotic stress induces several senescence-like processes in leaves, such as specific changes in gene expression and yellowing. These processes are dependent on the accumulation of jasmonates and on intact jasmonate signaling. This chapter describes the treatment of Arabidopsis thaliana leaves with sorbitol as an osmotic stress agent and the determination of the elicited phenotypes encompassing chlorophyll loss, degradation of plastidial membrane lipids, and induction of genes regulated by senescence and jasmonate.

  3. Phloem sugar flux and jasmonic acid-responsive cell wall invertase control extrafloral nectar secretion in Ricinus communis.

    PubMed

    Millán-Cañongo, Cynthia; Orona-Tamayo, Domancar; Heil, Martin

    2014-07-01

    Plants secrete extrafloral nectar (EFN) that attracts predators. The efficiency of the resulting anti-herbivore defense depends on the quantity and spatial distribution of EFN. Thus, according to the optimal defense hypothesis (ODH), plants should secrete EFN on the most valuable organs and when herbivore pressure is high. Ricinus communis plants secreted most EFN on the youngest (i.e., most valuable) leaves and after the simulation of herbivory via the application of jasmonic acid (JA). Here, we investigated the physiological mechanisms that might produce these seemingly adaptive spatiotemporal patterns. Cell wall invertase (CWIN; EC 3.2.1.26) was most active in the hours before peak EFN secretion, its decrease preceded the decrease in EFN secretion, and CWIN activity was inducible by JA. Thus, CWIN appears to be a central player in EFN secretion: its activation by JA is likely to cause the induction of EFN secretion after herbivory. Shading individual leaves decreased EFN secretion locally on these leaves with no effect on CWIN activity in the nectaries, which is likely to be because it decreased the content of sucrose, the substrate of CWIN, in the phloem. Our results demonstrate how the interplay of two physiological processes can cause ecologically relevant spatiotemporal patterns in a plant defense trait.

  4. Jasmonic acid-dependent and -independent signaling pathways control wound-induced gene activation in Arabidopsis thaliana.

    PubMed Central

    Titarenko, E; Rojo, E; León, J; Sánchez-Serrano, J J

    1997-01-01

    Plant response to mechanical injury includes gene activation both at the wound site and systemically in nondamaged tissues. The model developed for the wound-induced activation of the proteinase inhibitor II (Pin2) gene in potato (Solanum tuberosum) and tomato (Lycopersicon esculentum) establishes the involvement of the plant hormones abscisic acid and jasmonic acid (JA) as key components of the wound signal transduction pathway. To assess in Arabidopsis thaliana the role of these plant hormones in regulating wound-induced gene expression, we isolated wound- and JA-inducible genes by the differential mRNA display technique. Their patterns of expression upon mechanical wounding and hormonal treatments revealed differences in the spatial distribution of the transcripts and in the responsiveness of the analyzed genes to abscisic acid and JA. A correlation can be established between sensitivity to JA and the accumulation of the transcripts in systemic tissues upon wounding. A comparative study of the wound response in wild-type and JA-insensitive coi1 mutant plants indicated that in A. thaliana wound signals are transmitted via at least two different pathways. One of them does not involve JA as a mediator and is preferentially responsible for gene activation in the vicinity of the wound site, whereas the other requires JA perception and activates gene expression throughout the aerial part of the plant. PMID:9342878

  5. Language Control Abilities of Late Bilinguals

    ERIC Educational Resources Information Center

    Festman, Julia

    2012-01-01

    Although all bilinguals encounter cross-language interference (CLI), some bilinguals are more susceptible to interference than others. Here, we report on language performance of late bilinguals (Russian/German) on two bilingual tasks (interview, verbal fluency), their language use and switching habits. The only between-group difference was CLI:…

  6. The Arabidopsis DELAYED DEHISCENCE1 Gene Encodes an Enzyme in the Jasmonic Acid Synthesis Pathway

    PubMed Central

    Sanders, Paul M.; Lee, Pei Yun; Biesgen, Christian; Boone, James D.; Beals, Thomas P.; Weiler, Elmar W.; Goldberg, Robert B.

    2000-01-01

    delayed dehiscence1 is an Arabidopsis T-DNA mutant in which anthers release pollen grains too late for pollination to occur. The delayed dehiscence1 defect is caused by a delay in the stomium degeneration program. The gene disrupted in delayed dehiscence1 encodes 12-oxophytodienoate reductase, an enzyme in the jasmonic acid biosynthesis pathway. We rescued the mutant phenotype by exogenous application of jasmonic acid and obtained seed set from previously male-sterile plants. In situ hybridization studies showed that during the early stages of floral development, DELAYED DEHISCENCE1 mRNA accumulated within all floral organs. Later, DELAYED DEHISCENCE1 mRNA accumulated specifically within the pistil, petals, and stamen filaments. DELAYED DEHISCENCE1 mRNA was not detected in the stomium and septum cells of the anther that are involved in pollen release. The T-DNA insertion in delayed dehiscence1 eliminated both DELAYED DEHISCENCE1 mRNA accumulation and 12-oxophytodienoate reductase activity. These experiments suggest that jasmonic acid signaling plays a role in controlling the time of anther dehiscence within the flower. PMID:10899973

  7. The wound hormone jasmonate

    PubMed Central

    Koo, Abraham J.K.; Howe, Gregg A.

    2009-01-01

    Plant tissues are highly vulnerable to injury by herbivores, pathogens, mechanical stress, and other environmental insults. Optimal plant fitness in the face of these threats relies on complex signal transduction networks that link damage-associated signals to appropriate changes in metabolism, growth, and development. Many of these wound-induced adaptive responses are triggered by de novo synthesis of the plant hormone jasmonate (JA). Recent studies provide evidence that JA mediates systemic wound responses through distinct cell autonomous and nonautonomous pathways. In both pathways, bioactive JAs are recognized by an F-box protein-based receptor system that couples hormone binding to ubiquitin-dependent degradation of transcriptional repressor proteins. These results provide a new framework for understanding how plants recognize and respond to tissue injury. PMID:19695649

  8. Lotus japonicus nodulation is photomorphogenetically controlled by sensing the red/far red (R/FR) ratio through jasmonic acid (JA) signaling

    PubMed Central

    Suzuki, Akihiro; Suriyagoda, Lalith; Shigeyama, Tamaki; Tominaga, Akiyoshi; Sasaki, Masayo; Hiratsuka, Yoshimi; Yoshinaga, Aya; Arima, Susumu; Agarie, Sakae; Sakai, Tatsuya; Inada, Sayaka; Jikumaru, Yusuke; Kamiya, Yuji; Uchiumi, Toshiki; Abe, Mikiko; Hashiguchi, Masatsugu; Akashi, Ryo; Sato, Shusei; Kaneko, Takakazu; Tabata, Satoshi; Hirsch, Ann M.

    2011-01-01

    Light is critical for supplying carbon to the energetically expensive, nitrogen-fixing symbiosis between legumes and rhizobia. Here, we show that phytochrome B (phyB) is part of the monitoring system to detect suboptimal light conditions, which normally suppress Lotus japonicus nodule development after Mesorhizobium loti inoculation. We found that the number of nodules produced by L. japonicus phyB mutants is significantly reduced compared with the number produced of WT Miyakojima MG20. To explore causes other than photoassimilate production, the possibility that local control by the root genotype occurred was investigated by grafting experiments. The results showed that the shoot and not the root genotype is responsible for root nodule formation. To explore systemic control mechanisms exclusive of photoassimilation, we moved WT MG20 plants from white light to conditions that differed in their ratios of low or high red/far red (R/FR) light. In low R/FR light, the number of MG20 root nodules dramatically decreased compared with plants grown in high R/FR, although photoassimilate content was higher for plants grown under low R/FR. Also, the expression of jasmonic acid (JA) -responsive genes decreased in both low R/FR light-grown WT and white light-grown phyB mutant plants, and it correlated with decreased jasmonoyl-isoleucine content in the phyB mutant. Moreover, both infection thread formation and root nodule formation were positively influenced by JA treatment of WT plants grown in low R/FR light and white light-grown phyB mutants. Together, these results indicate that root nodule formation is photomorphogenetically controlled by sensing the R/FR ratio through JA signaling. PMID:21930895

  9. The NAC-like gene ANTHER INDEHISCENCE FACTOR acts as a repressor that controls anther dehiscence by regulating genes in the jasmonate biosynthesis pathway in Arabidopsis

    PubMed Central

    Yang, Chang-Hsien

    2014-01-01

    ANTHER INDEHISCENCE FACTOR (AIF), a NAC-like gene, was identified in Arabidopsis. In AIF:GUS flowers, β-glucuronidase (GUS) activity was detected in the anther, the upper parts of the filaments, and in the pollen of stage 7–9 young flower buds; GUS activity was reduced in mature flowers. Yellow fluorescent protein (YFP)+AIF-C fusion proteins, which lacked a transmembrane domain, accumulated in the nuclei of the Arabidopsis cells, whereas the YFP+AIF fusion proteins accumulated in the membrane and were absent in the nuclei. Further detection of a cleaved AIF protein in flowers revealed that AIF needs to be processed and released from the endoplasmic reticulum in order to function. The ectopic expression of AIF-C caused a male-sterile phenotype with indehiscent anthers throughout flower development in Arabidopsis. The presence of a repressor domain in AIF and the similar phenotype of indehiscent anthers in AIF-C+SRDX plants suggest that AIF acts as a repressor. The defect in anther dehiscence was due to the down-regulation of genes that participate in jasmonic acid (JA) biosynthesis, such as DAD1/AOS/AOC3/OPR3/OPCL1. The external application of JA rescued the anther indehiscence in AIF-C and AIF-C+SRDX flowers. In AIF-C+VP16 plants, which are transgenic dominant-negative mutants in which AIF is converted to a potent activator via fusion to a VP16-AD motif, the anther dehiscence was promoted, and the expression of DAD1/AOS/AOC3/OPR3/OPCL1 was up-regulated. Furthermore, the suppression of AIF through an antisense strategy resulted in a mutant phenotype similar to that observed in the AIF-C+VP16 flowers. The present data suggest a role for AIF in controlling anther dehiscence by suppressing the expression of JA biosynthesis genes in Arabidopsis. PMID:24323506

  10. The Rise and Fall of Jasmonate Biological Activities.

    PubMed

    Heitz, Thierry; Smirnova, Ekaterina; Widemann, Emilie; Aubert, Yann; Pinot, Franck; Ménard, Rozenn

    2016-01-01

    Jasmonates (JAs) constitute a major class of plant regulators that coordinate responses to biotic and abiotic threats and important aspects of plant development. The core biosynthetic pathway converts linolenic acid released from plastid membrane lipids to the cyclopentenone cis-oxo-phytodienoic acid (OPDA) that is further reduced and shortened to jasmonic acid (JA) in peroxisomes. Abundant pools of OPDA esterified to plastid lipids also occur upon stress, mainly in the Arabidopsis genus. Long thought to be the bioactive hormone, JA only gains its pleiotropic hormonal properties upon conjugation into jasmonoyl-isoleucine (JA-Ile). The signaling pathway triggered when JA-Ile promotes the assembly of COI1-JAZ (Coronatine Insensitive 1-JAsmonate Zim domain) co-receptor complexes has been the focus of most recent research in the jasmonate field. In parallel, OPDA and several other JA derivatives are recognized for their separate activities and contribute to the diversity of jasmonate action in plant physiology. We summarize in this chapter the properties of different bioactive JAs and review elements known for their perception and signal transduction. Much progress has also been gained on the enzymatic processes governing JA-Ile removal. Two JA-Ile catabolic pathways, operating through ω-oxidation (cytochromes P450) or conjugate cleavage (amido hydrolases) shape signal dynamics to allow optimal control on defense. JA-Ile turnover not only participates in signal attenuation, but also impact the homeostasis of the entire JA metabolic pathway.

  11. JASMONATE-TRIGGERED PLANT IMMUNITY

    PubMed Central

    Campos, Marcelo L.; Kang, Jin-Ho; Howe, Gregg A.

    2014-01-01

    The plant hormone jasmonate (JA) exerts direct control over the production of chemical defense compounds that confer resistance to a remarkable spectrum of plant-associated organisms, ranging from microbial pathogens to vertebrate herbivores. The underlying mechanism of JA-triggered immunity (JATI) can be conceptualized as a multi-stage signal transduction cascade involving: i) pattern recognition receptors (PRRs) that couple the perception of danger signals to rapid synthesis of bioactive JA; ii) an evolutionarily conserved JA signaling module that links fluctuating JA levels to changes in the abundance of transcriptional repressor proteins; and iii) activation (de-repression) of transcription factors that orchestrate the expression of myriad chemical and morphological defense traits. Multiple negative feedback loops act in concert to restrain the duration and amplitude of defense responses, presumably to mitigate potential fitness costs of JATI. The convergence of diverse plant- and non-plant-derived signals on the core JA module indicates that JATI is a general response to perceived danger. However, the modular structure of JATI may accommodate attacker-specific defense responses through evolutionary innovation of PRRs (inputs) and defense traits (outputs). The efficacy of JATI as a defense strategy is highlighted by its capacity to shape natural populations of plant attackers, as well as the propensity of plant-associated organisms to subvert or otherwise manipulate JA signaling. As both a cellular hub for integrating informational cues from the environment and a common target of pathogen effectors, the core JA module provides a focal point for understanding immune system networks and the evolution of chemical diversity in the plant kingdom. PMID:24973116

  12. Jasmonic Acid and Its Precursor 12-Oxophytodienoic Acid Control Different Aspects of Constitutive and Induced Herbivore Defenses in Tomato1[W][OPEN

    PubMed Central

    Bosch, Marko; Wright, Louwrance P.; Gershenzon, Jonathan; Wasternack, Claus; Hause, Bettina; Schaller, Andreas; Stintzi, Annick

    2014-01-01

    The jasmonate family of growth regulators includes the isoleucine (Ile) conjugate of jasmonic acid (JA-Ile) and its biosynthetic precursor 12-oxophytodienoic acid (OPDA) as signaling molecules. To assess the relative contribution of JA/JA-Ile and OPDA to insect resistance in tomato (Solanum lycopersicum), we silenced the expression of OPDA reductase3 (OPR3) by RNA interference (RNAi). Consistent with a block in the biosynthetic pathway downstream of OPDA, OPR3-RNAi plants contained wild-type levels of OPDA but failed to accumulate JA or JA-Ile after wounding. JA/JA-Ile deficiency in OPR3-RNAi plants resulted in reduced trichome formation and impaired monoterpene and sesquiterpene production. The loss of these JA/JA-Ile -dependent defense traits rendered them more attractive to the specialist herbivore Manduca sexta with respect to feeding and oviposition. Oviposition preference resulted from reduced levels of repellant monoterpenes and sesquiterpenes. Feeding preference, on the other hand, was caused by increased production of cis-3-hexenal acting as a feeding stimulant for M. sexta larvae in OPR3-RNAi plants. Despite impaired constitutive defenses and increased palatability of OPR3-RNAi leaves, larval development was indistinguishable on OPR3-RNAi and wild-type plants, and was much delayed compared with development on the jasmonic acid-insensitive1 (jai1) mutant. Apparently, signaling through JAI1, the tomato ortholog of the ubiquitin ligase CORONATINE INSENSITIVE1 in Arabidopsis (Arabidopsis thaliana), is required for defense, whereas the conversion of OPDA to JA/JA-Ile is not. Comparing the signaling activities of OPDA and JA/JA-Ile, we found that OPDA can substitute for JA/JA-Ile in the local induction of defense gene expression, but the production of JA/JA-Ile is required for a systemic response. PMID:25073705

  13. BIOSYNTHESIS AND ACTION OF JASMONATES IN PLANTS.

    PubMed

    Creelman, Robert A.; Mullet, John E.

    1997-06-01

    Jasmonic acid and its derivatives can modulate aspects of fruit ripening, production of viable pollen, root growth, tendril coiling, and plant resistance to insects and pathogens. Jasmonate activates genes involved in pathogen and insect resistance, and genes encoding vegetative storage proteins, but represses genes encoding proteins involved in photosynthesis. Jasmonic acid is derived from linolenic acid, and most of the enzymes in the biosynthetic pathway have been extensively characterized. Modulation of lipoxygenase and allene oxide synthase gene expression in transgenic plants raises new questions about the compartmentation of the biosynthetic pathway and its regulation. The activation of jasmonic acid biosynthesis by cell wall elicitors, the peptide systemin, and other compounds will be related to the function of jasmonates in plants. Jasmonate modulates gene expression at the level of translation, RNA processing, and transcription. Promoter elements that mediate responses to jasmonate have been isolated. This review covers recent advances in our understanding of how jasmonate biosynthesis is regulated and relates this information to knowledge of jasmonate modulated gene expression.

  14. Control of anthracnose disease via increased activity of defence related enzymes in 'Hass' avocado fruit treated with methyl jasmonate and methyl salicylate.

    PubMed

    Glowacz, Marcin; Roets, Nico; Sivakumar, Dharini

    2017-11-01

    Development of anthracnose disease caused by Colletotrichum gloeosporioides Penz. is one of the major issues within the avocado supply chain. Exposure to methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours at 10 and 100µmoll(-1) was investigated as an alternative solution to commercial fungicide - prochloraz® that is currently being used by the industry. The incidence of anthracnose disease was found to be significantly reduced in 'Hass' avocado fruit treated with MeJA or MeSA vapours, especially at 100μmoll(-1). The mechanism involved enhanced activity of defence related enzymes, i.e. chitinase, β-1,3-glucanase and PAL, and higher content of epicatechin. Copyright © 2017. Published by Elsevier Ltd.

  15. Jasmonate Controls Leaf Growth by Repressing Cell Proliferation and the Onset of Endoreduplication while Maintaining a Potential Stand-By Mode1[W][OA

    PubMed Central

    Noir, Sandra; Bömer, Moritz; Takahashi, Naoki; Ishida, Takashi; Tsui, Tjir-Li; Balbi, Virginia; Shanahan, Hugh; Sugimoto, Keiko; Devoto, Alessandra

    2013-01-01

    Phytohormones regulate plant growth from cell division to organ development. Jasmonates (JAs) are signaling molecules that have been implicated in stress-induced responses. However, they have also been shown to inhibit plant growth, but the mechanisms are not well understood. The effects of methyl jasmonate (MeJA) on leaf growth regulation were investigated in Arabidopsis (Arabidopsis thaliana) mutants altered in JA synthesis and perception, allene oxide synthase and coi1-16B (for coronatine insensitive1), respectively. We show that MeJA inhibits leaf growth through the JA receptor COI1 by reducing both cell number and size. Further investigations using flow cytometry analyses allowed us to evaluate ploidy levels and to monitor cell cycle progression in leaves and cotyledons of Arabidopsis and/or Nicotiana benthamiana at different stages of development. Additionally, a novel global transcription profiling analysis involving continuous treatment with MeJA was carried out to identify the molecular players whose expression is regulated during leaf development by this hormone and COI1. The results of these studies revealed that MeJA delays the switch from the mitotic cell cycle to the endoreduplication cycle, which accompanies cell expansion, in a COI1-dependent manner and inhibits the mitotic cycle itself, arresting cells in G1 phase prior to the S-phase transition. Significantly, we show that MeJA activates critical regulators of endoreduplication and affects the expression of key determinants of DNA replication. Our discoveries also suggest that MeJA may contribute to the maintenance of a cellular “stand-by mode” by keeping the expression of ribosomal genes at an elevated level. Finally, we propose a novel model for MeJA-regulated COI1-dependent leaf growth inhibition. PMID:23439917

  16. Jasmonate controls leaf growth by repressing cell proliferation and the onset of endoreduplication while maintaining a potential stand-by mode.

    PubMed

    Noir, Sandra; Bömer, Moritz; Takahashi, Naoki; Ishida, Takashi; Tsui, Tjir-Li; Balbi, Virginia; Shanahan, Hugh; Sugimoto, Keiko; Devoto, Alessandra

    2013-04-01

    Phytohormones regulate plant growth from cell division to organ development. Jasmonates (JAs) are signaling molecules that have been implicated in stress-induced responses. However, they have also been shown to inhibit plant growth, but the mechanisms are not well understood. The effects of methyl jasmonate (MeJA) on leaf growth regulation were investigated in Arabidopsis (Arabidopsis thaliana) mutants altered in JA synthesis and perception, allene oxide synthase and coi1-16B (for coronatine insensitive1), respectively. We show that MeJA inhibits leaf growth through the JA receptor COI1 by reducing both cell number and size. Further investigations using flow cytometry analyses allowed us to evaluate ploidy levels and to monitor cell cycle progression in leaves and cotyledons of Arabidopsis and/or Nicotiana benthamiana at different stages of development. Additionally, a novel global transcription profiling analysis involving continuous treatment with MeJA was carried out to identify the molecular players whose expression is regulated during leaf development by this hormone and COI1. The results of these studies revealed that MeJA delays the switch from the mitotic cell cycle to the endoreduplication cycle, which accompanies cell expansion, in a COI1-dependent manner and inhibits the mitotic cycle itself, arresting cells in G1 phase prior to the S-phase transition. Significantly, we show that MeJA activates critical regulators of endoreduplication and affects the expression of key determinants of DNA replication. Our discoveries also suggest that MeJA may contribute to the maintenance of a cellular "stand-by mode" by keeping the expression of ribosomal genes at an elevated level. Finally, we propose a novel model for MeJA-regulated COI1-dependent leaf growth inhibition.

  17. Jasmonate signaling in plant development and defense response to multiple (a)biotic stresses.

    PubMed

    Santino, Angelo; Taurino, Marco; De Domenico, Stefania; Bonsegna, Stefania; Poltronieri, Palmiro; Pastor, Victoria; Flors, Victor

    2013-07-01

    Plants frequently live in environments characterized by the presence of simultaneous and different stresses. The intricate and finely tuned molecular mechanisms activated by plants in response to abiotic and biotic environmental factors are not well understood, and less is known about the integrative signals and convergence points activated by plants in response to multiple (a)biotic stresses. Phytohormones play a key role in plant development and response to (a)biotic stresses. Among these, one of the most important signaling molecules is an oxylipin, the plant hormone jasmonic acid. Oxylipins are derived from oxygenation of polyunsaturated fatty acids. Jasmonic acid and its volatile derivative methyl jasmonate have been considered for a long time to be the bioactive forms due to their physiological effects and abundance in the plant. However, more recent studies showed unambiguously that they are only precursors of the active forms represented by some amino acid conjugates. Upon developmental or environmental stimuli, jasmonates are synthesized and accumulate transiently. Upon perception, jasmonate signal transduction process is finely tuned by a complex mechanism comprising specific repressor proteins which in turn control a number of transcription factors regulating the expression of jasmonate responsive genes. We discuss the latest discoveries about the role of jasmonates in plants resistance mechanism against biotic and abiotic stresses. Finally, the deep interplay of different phytohormones in stresses signaling will be also discussed.

  18. Natural variation of potato allene oxide synthase 2 causes differential levels of jasmonates and pathogen resistance in Arabidopsis

    PubMed Central

    Pajerowska-Mukhtar, Karolina M.; Mukhtar, M. Shahid; Guex, Nicolas; Halim, Vincentius A.; Rosahl, Sabine; Somssich, Imre E.

    2008-01-01

    Natural variation of plant pathogen resistance is often quantitative. This type of resistance can be genetically dissected in quantitative resistance loci (QRL). To unravel the molecular basis of QRL in potato (Solanum tuberosum), we employed the model plant Arabidopsis thaliana for functional analysis of natural variants of potato allene oxide synthase 2 (StAOS2). StAOS2 is a candidate gene for QRL on potato chromosome XI against the oömycete Phytophthora infestans causing late blight, and the bacterium Erwinia carotovora ssp. atroseptica causing stem black leg and tuber soft rot, both devastating diseases in potato cultivation. StAOS2 encodes a cytochrome P450 enzyme that is essential for biosynthesis of the defense signaling molecule jasmonic acid. Allele non-specific dsRNAi-mediated silencing of StAOS2 in potato drastically reduced jasmonic acid production and compromised quantitative late blight resistance. Five natural StAOS2 alleles were expressed in the null Arabidopsis aos mutant under control of the Arabidopsis AOS promoter and tested for differential complementation phenotypes. The aos mutant phenotypes evaluated were lack of jasmonates, male sterility and susceptibility to Erwinia carotovora ssp. carotovora. StAOS2 alleles that were associated with increased disease resistance in potato complemented all aos mutant phenotypes better than StAOS2 alleles associated with increased susceptibility. First structure models of ‘quantitative resistant’ versus ‘quantitative susceptible’ StAOS2 alleles suggested potential mechanisms for their differential activity. Our results demonstrate how a candidate gene approach in combination with using the homologous Arabidopsis mutant as functional reporter can help to dissect the molecular basis of complex traits in non model crop plants. Electronic supplementary material The online version of this article (doi:10.1007/s00425-008-0737-x) contains supplementary material, which is available to authorized users

  19. Late-acting dominant lethal genetic systems and mosquito control

    PubMed Central

    Phuc, Hoang Kim; Andreasen, Morten H; Burton, Rosemary S; Vass, Céline; Epton, Matthew J; Pape, Gavin; Fu, Guoliang; Condon, Kirsty C; Scaife, Sarah; Donnelly, Christl A; Coleman, Paul G; White-Cooper, Helen; Alphey, Luke

    2007-01-01

    Background Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT). SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with strong density-dependent effects will tend to be resistant to SIT-based control as the population-reducing effect of induced sterility will tend to be offset by reduced density-dependent mortality. Results We investigated by mathematical modeling the effect of manipulating the stage of development at which death occurs (lethal phase) in an SIT program against a density-dependence-limited insect population. We found late-acting lethality to be considerably more effective than early-acting lethality. No such strains of a vector insect have been described, so as a proof-of-principle we constructed a strain of the principal vector of the dengue and yellow fever viruses, Aedes (Stegomyia) aegypti, with the necessary properties of dominant, repressible, highly penetrant, late-acting lethality. Conclusion Conventional SIT induces early-acting (embryonic) lethality, but genetic methods potentially allow the lethal phase to be tailored to the program. For insects with strong density-dependence, we show that lethality after the density-dependent phase would be a considerable improvement over conventional methods. For density-dependent parameters estimated from field data for Aedes aegypti, the critical release ratio for population elimination is modeled to be 27% to 540% greater for early-acting rather than late-acting lethality. Our success in developing a mosquito strain with the key features that the modeling indicated were desirable demonstrates the feasibility of this approach for improved SIT for disease

  20. Late-acting dominant lethal genetic systems and mosquito control.

    PubMed

    Phuc, Hoang Kim; Andreasen, Morten H; Burton, Rosemary S; Vass, Céline; Epton, Matthew J; Pape, Gavin; Fu, Guoliang; Condon, Kirsty C; Scaife, Sarah; Donnelly, Christl A; Coleman, Paul G; White-Cooper, Helen; Alphey, Luke

    2007-03-20

    Reduction or elimination of vector populations will tend to reduce or eliminate transmission of vector-borne diseases. One potential method for environmentally-friendly, species-specific population control is the Sterile Insect Technique (SIT). SIT has not been widely used against insect disease vectors such as mosquitoes, in part because of various practical difficulties in rearing, sterilization and distribution. Additionally, vector populations with strong density-dependent effects will tend to be resistant to SIT-based control as the population-reducing effect of induced sterility will tend to be offset by reduced density-dependent mortality. We investigated by mathematical modeling the effect of manipulating the stage of development at which death occurs (lethal phase) in an SIT program against a density-dependence-limited insect population. We found late-acting lethality to be considerably more effective than early-acting lethality. No such strains of a vector insect have been described, so as a proof-of-principle we constructed a strain of the principal vector of the dengue and yellow fever viruses, Aedes (Stegomyia) aegypti, with the necessary properties of dominant, repressible, highly penetrant, late-acting lethality. Conventional SIT induces early-acting (embryonic) lethality, but genetic methods potentially allow the lethal phase to be tailored to the program. For insects with strong density-dependence, we show that lethality after the density-dependent phase would be a considerable improvement over conventional methods. For density-dependent parameters estimated from field data for Aedes aegypti, the critical release ratio for population elimination is modeled to be 27% to 540% greater for early-acting rather than late-acting lethality. Our success in developing a mosquito strain with the key features that the modeling indicated were desirable demonstrates the feasibility of this approach for improved SIT for disease control.

  1. Phenotyping jasmonate regulation of root growth.

    PubMed

    Kellermeier, Fabian; Amtmann, Anna

    2013-01-01

    Root architecture is a complex and highly plastic feature of higher plants. Direct treatments with jasmonates and alterations in jasmonate signaling have been shown to elicit a range of root phenotypes. Here, we describe a fast, noninvasive, and semiautomatic method to monitor root architectural responses to environmental stimuli using plant tissue culture and the software tool EZ-RHIZO.

  2. BIOPACK: the ground controlled late access biological research facility.

    PubMed

    van Loon, Jack J W A

    2004-03-01

    Future Space Shuttle flights shall be characterized by activities necessary to further build the International Space Station, ISS. During these missions limited resources are available to conduct biological experiments in space. The Shuttles' Middeck is a very suitable place to conduct science during the ISS assembly missions or dedicated science missions. The BIOPACK, which flew its first mission during the STS-107, provides a versatile Middeck Locker based research tool for gravitational biology studies. The core facility occupies the space of only two Middeck Lockers. Experiment temperatures are controlled for bacteria, plant, invertebrate and mammalian cultures. Gravity levels and profiles can be set ranging from 0 to 2.0 x g on three independent centrifuges. This provides the experimenter with a 1.0 x g on-board reference and intermediate hypogravity and hypergravity data points to investigate e.g. threshold levels in biological responses. Temperature sensitive items can be stored in the facilities' -10 degrees C and +4 degrees C stowage areas. During STS-107 the facility also included a small glovebox (GBX) and passive temperature controlled units (PTCU). The GBX provides the experimenter with two extra levels of containment for safe sample handling. This biological research facility is a late access (L-10 hrs) laboratory, which, when reaching orbit, could automatically be starting up reducing important experiment lag-time and valuable crew time. The system is completely telecommanded when needed. During flight system parameters like temperatures, centrifuge speeds, experiment commanding or sensor readouts can be monitored and changed when needed. Although ISS provides a wide range of research facilities there is still need for an STS-based late access facility such as the BIOPACK providing experimenters with a very versatile research cabinet for biological experiments under microgravity and in-flight control conditions.

  3. Jasmonates during senescence: signals or products of metabolism?

    PubMed

    Seltmann, Martin A; Hussels, Wiebke; Berger, Susanne

    2010-11-01

    Jasmonic acid and derivatives are oxylipin signaling compounds derived from linolenic acid. Jasmonates accumulate during natural and dark-induced senescence but the increase in these compounds is not essential for the initiation or progression of these senescence processes. Here we report that during natural and dark-induced senescence the increase in jasmonate levels does not trigger jasmonate signaling. Furthermore we provide evidence that jasmonate production might result from membrane turnover during dark-induced senescence.

  4. Climatic controls on late Pleistocene alluvial fans, Cyprus

    NASA Astrophysics Data System (ADS)

    Waters, J. V.; Jones, S. J.; Armstrong, H. A.

    2010-03-01

    Alluvial fans are commonly associated with tectonically active mountain ranges and tectonism is frequently held responsible for abrupt coarsening and cyclical sedimentation of alluvial fan sequences. Whilst it is accepted that tectonism provides the opportunity for alluvial fan development through the creation of topography, increasing gradients of fluvial systems supplying sediments, and creating accommodation for the storage of sediment flux, the role of climate in fan development is frequently neglected. The hypothesis that climatically controlled events can produce recognisable sedimentary signatures in alluvial fan deposits is tested in the active supra-subduction zone setting of the late Pleistocene of southern Cyprus. This study demonstrates through architectural analysis and the reconstruction of palaeoflood hydrology a recorded pattern of increasing and decreasing palaeoflow dynamics, with switches from a wetter to drier mode, clearly exhibited by changes in the sedimentology of the fan. At the present day Cyprus has a semi-arid climate and is influenced by a strongly seasonal rainfall pattern, largely restricted to the winter months (plus rare occurrences of summer cyclones). However at precession minima increased activity of western Mediterranean depressions produces wetter summers. Using inference we propose that longer-term increases in rainfall increased river discharge as recorded in the fan palaeoflood hydrology and occurred at minima in the precession. These periods correlate with the deposition of conglomeratic channels and open framework gravels. Drier periods are exhibited by sandier braided fluvial deposits. Shorter term or seasonal change is recorded in the form of 2nd and 3rd low order bounding surfaces. This increased activity of Mediterranean summer depressions increased precipitation to the wider Levantine area and was coincident with increased intensity of the north African and Indian Ocean (SW) monsoons. The resultant increase in river

  5. Jasmonic acid induces resistance to economically important insect pests in winter wheat.

    PubMed

    El-Wakeil, Nabil E; Volkmar, Christa; Sallam, Ahmed A

    2010-05-01

    Insect damage induces chemical changes in plants, and frequently these changes are part of a defensive response to the insect injury. Induced resistance was activated in winter wheat using a foliar application of synthetic jasmonic acid. Field trials were conducted to observe effects of jasmonic acid application on some wheat insects. Two wheat cultivars (Cubus and Tommi) were sprayed twice at growth stages (GS) 41 and 59 with two concentrations of jasmonic acid, along with control plots that were sprayed with water. There was a significant difference in the number of thrips and wheat blossom midges (WBM) among treatments in both cultivars. Plants in control plots had higher numbers of thrips and midges than in treated plots. There were higher numbers of thrips in the Tommi cultivar than in the Cubus cultivar, while the latter had higher numbers of WBM larvae than the Tommi cultivar. There was a positive correlation between WBM numbers and infested kernels in both cultivars. This study also indicated that jasmonic acid enhances the wheat yield in sprayed plots compared with control plots. The results indicate that jasmonic acid induced pest resistance in wheat plants and may act as a resistance mechanism of wheat against insect herbivores.

  6. Ethylene and jasmonic acid act as negative modulators during mutualistic symbiosis between Laccaria bicolor and Populus roots.

    PubMed

    Plett, Jonathan M; Khachane, Amit; Ouassou, Malika; Sundberg, Björn; Kohler, Annegret; Martin, Francis

    2014-04-01

    The plant hormones ethylene, jasmonic acid and salicylic acid have interconnecting roles during the response of plant tissues to mutualistic and pathogenic symbionts. We used morphological studies of transgenic- or hormone-treated Populus roots as well as whole-genome oligoarrays to examine how these hormones affect root colonization by the mutualistic ectomycorrhizal fungus Laccaria bicolor S238N. We found that genes regulated by ethylene, jasmonic acid and salicylic acid were regulated in the late stages of the interaction between L. bicolor and poplar. Both ethylene and jasmonic acid treatments were found to impede fungal colonization of roots, and this effect was correlated to an increase in the expression of certain transcription factors (e.g. ETHYLENE RESPONSE FACTOR1) and a decrease in the expression of genes associated with microbial perception and cell wall modification. Further, we found that ethylene and jasmonic acid showed extensive transcriptional cross-talk, cross-talk that was opposed by salicylic acid signaling. We conclude that ethylene and jasmonic acid pathways are induced late in the colonization of root tissues in order to limit fungal growth within roots. This induction is probably an adaptive response by the plant such that its growth and vigor are not compromised by the fungus. © 2013 The Authors New Phytologist © 2013 New Phytologist Trust.

  7. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS.

    PubMed

    Huang, Zhi-Hong; Wang, Zhi-Li; Shi, Bao-Lin; Wei, Dong; Chen, Jian-Xin; Wang, Su-Li; Gao, Bao-Jia

    2015-01-01

    Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

  8. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS

    PubMed Central

    Huang, Zhi-hong; Wang, Zhi-li; Shi, Bao-lin; Wei, Dong; Chen, Jian-xin; Wang, Su-li; Gao, Bao-jia

    2015-01-01

    Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite. PMID:26457083

  9. Methyl jasmonate induces extracellular pathogenesis-related proteins in cell cultures of Capsicum chinense

    PubMed Central

    Belchí-Navarro, Sarai; Barceló, Alfonso Ros

    2011-01-01

    Suspension cultured cells of Capsicum chinense secrete proteins to the culture medium in both control conditions and under methyl jasmonate treatment. The exogenous application of methyl jasmonate induced the accumulation of putative pathogenesis-related proteins, class I chitinase, leucin-rich repeat protein, NtPRp27-like protein and pectinesterase which were also found in suspension cultured cells of C. annuum elicited with methyl jasmonate. However, a germin-like protein, which has never been described in methyl jasmonate-elicited C. chinense suspension cultured cells, was found. The different effects described as being the result of exogenous application of signalling molecules like methyl jasmonate on the expression of germin-like protein suggest that germin-like proteins may play a variety of roles in protecting plants against pathogen attacks and different stresses. Further studies will be necessary to characterize the differential expression of these pathogenesis-related proteins and to throw light on the complexity of their regulation. PMID:21346408

  10. The Ubiquitin System and Jasmonate Signaling

    PubMed Central

    Nagels Durand, Astrid; Pauwels, Laurens; Goossens, Alain

    2016-01-01

    The ubiquitin (Ub) system is involved in most, if not all, biological processes in eukaryotes. The major specificity determinants of this system are the E3 ligases, which bind and ubiquitinate specific sets of proteins and are thereby responsible for target recruitment to the proteasome or other cellular processing machineries. The Ub system contributes to the regulation of the production, perception and signal transduction of plant hormones. Jasmonic acid (JA) and its derivatives, known as jasmonates (JAs), act as signaling compounds regulating plant development and plant responses to various biotic and abiotic stress conditions. We provide here an overview of the current understanding of the Ub system involved in JA signaling. PMID:27135226

  11. Antagonistic effects of abscisic acid and jasmonates on salt stress-inducible transcripts in rice roots.

    PubMed Central

    Moons, A; Prinsen, E; Bauw, G; Van Montagu, M

    1997-01-01

    Abscisic acid (ABA) and jasmonates have been implicated in responses to water deficit and wounding. We compared the molecular and physiological effects of jasmonic acid (JA) (< or = 10 microM), ABA, and salt stress in roots of rice. JA markedly induced a cationic peroxidase, two novel 32- and 28-kD proteins, acidic PR-1 and PR-10 pathogenesis-related proteins, and the salt stress-responsive SalT protein in roots. Most JA-responsive proteins (JIPs) from roots also accumulated when plants were subjected to salt stress. None of the JIPs accumulated when plants were treated with ABA. JA did not induce an ABA-responsive group 3 late-embryogenesis abundant (LEA) protein. Salt stress and ABA but not JA induced oslea3 transcript accumulation. By contrast, JA, ABA, and salt stress induced transcript accumulation of salT and osdrr, which encodes a rice PR-10 protein. However, ABA also negatively affected salT transcript accumulation, whereas JA negatively affected ABA-induced oslea3 transcript levels. Endogenous root ABA and methyl jasmonate levels showed a differential increase with the dose and the duration of salt stress. The results indicate that ABA and jasmonates antagonistically regulated the expression of salt stress-inducible proteins associated with water deficit or defense responses. PMID:9437865

  12. The impact of early bilingualism on controlling a language learned late: an ERP study

    PubMed Central

    Martin, Clara D.; Strijkers, Kristof; Santesteban, Mikel; Escera, Carles; Hartsuiker, Robert J.; Costa, Albert

    2013-01-01

    This study asks whether early bilingual speakers who have already developed a language control mechanism to handle two languages control a dominant and a late acquired language in the same way as late bilingual speakers. We therefore, compared event-related potentials in a language switching task in two groups of participants switching between a dominant (L1) and a weak late acquired language (L3). Early bilingual late learners of an L3 showed a different ERP pattern (larger N2 mean amplitude) as late bilingual late learners of an L3. Even though the relative strength of languages was similar in both groups (a dominant and a weak late acquired language), they controlled their language output in a different manner. Moreover, the N2 was similar in two groups of early bilinguals tested in languages of different strength. We conclude that early bilingual learners of an L3 do not control languages in the same way as late bilingual L3 learners –who have not achieved native-like proficiency in their L2– do. This difference might explain some of the advantages early bilinguals have when learning new languages. PMID:24204355

  13. Connectivity controls on the late Miocene eastern Mediterranean fish fauna

    NASA Astrophysics Data System (ADS)

    Agiadi, Konstantina; Antonarakou, Assimina; Kontakiotis, George; Kafousia, Nefeli; Moissette, Pierre; Cornée, Jean-Jacques; Manoutsoglou, Emmanouil; Karakitsios, Vasileios

    2016-06-01

    Environmental change significantly affects the production of fish resources and their dependent societies. The paleontological record offers unique insight into the effects of long-term paleoenvironmental variability on the fish species' distributions and abundances. In the present study, we investigate the late Miocene (7.5-6.5 Ma) fish assemblages of the Potamida section in western Crete (eastern Mediterranean). The determined fish taxa are examined in a paleobiogeographic context, with regard to their geographic and stratigraphic distribution from the early Miocene (~13 Ma) through today. In addition, present-day ecological data are used to reconstruct the paleoenvironmental conditions in the study area. Planktonic foraminifer biostratigraphy significantly improves the earlier dating of the studied sequence. The late Miocene fish fauna of Potamida includes 35 taxa (seven in open nomenclature) from 13 teleost families. The eastern Mediterranean biostratigraphic and geographic distribution of 32 taxa is significantly expanded into the Tortonian, whereas 13 species are recorded for the first time from the Messinian. Four stages are distinguished in the area's paleoenvironmental evolution. (1) The Potamida area was an open marine environment with depths exceeding 150 m between ~7.5-7.45 Ma. (2) Between 7.45-7.36 Ma, the results suggest depths between 300-400 m. (3) The depositional depth increases between 7.36-7.28 Ma to 400-550 m. (4) Later on, approximately between 6.8-6.6 Ma, the depth is again estimated around 100-150 m.

  14. Connectivity controls on the late Miocene eastern Mediterranean fish fauna

    NASA Astrophysics Data System (ADS)

    Agiadi, Konstantina; Antonarakou, Assimina; Kontakiotis, George; Kafousia, Nefeli; Moissette, Pierre; Cornée, Jean-Jacques; Manoutsoglou, Emmanouil; Karakitsios, Vasileios

    2017-04-01

    Environmental change significantly affects the production of fish resources and their dependent societies. The paleontological record offers unique insight into the effects of long-term paleoenvironmental variability on the fish species' distributions and abundances. In the present study, we investigate the late Miocene (7.5-6.5 Ma) fish assemblages of the Potamida section in western Crete (eastern Mediterranean). The determined fish taxa are examined in a paleobiogeographic context, with regard to their geographic and stratigraphic distribution from the early Miocene ( 13 Ma) through today. In addition, present-day ecological data are used to reconstruct the paleoenvironmental conditions in the study area. Planktonic foraminifer biostratigraphy significantly improves the earlier dating of the studied sequence. The late Miocene fish fauna of Potamida includes 35 taxa (seven in open nomenclature) from 13 teleost families. The eastern Mediterranean biostratigraphic and geographic distribution of 32 taxa is significantly expanded into the Tortonian, whereas 13 species are recorded for the first time from the Messinian. Four stages are distinguished in the area's paleoenvironmental evolution. (1) The Potamida area was an open marine environment with depths exceeding 150 m between 7.5-7.45 Ma. (2) Between 7.45-7.36 Ma, the results suggest depths between 300-400 m. (3) The depositional depth increases between 7.36-7.28 Ma to 400-550 m. (4) Later on, approximately between 6.8-6.6 Ma, the depth is again estimated around 100-150 m.

  15. The anti-ageing potential of a new jasmonic acid derivative (LR2412): in vitro evaluation using reconstructed epidermis Episkin™.

    PubMed

    Michelet, Jean F; Olive, Christian; Rieux, Elodie; Fagot, Dominique; Simonetti, Lucie; Galey, Jean B; Dalko-Csiba, Maria; Bernard, Bruno A; Pereira, Rui

    2012-05-01

    Jasmonic acid is involved in plant wound repair and tissue regeneration, but no study has been reported in human skin. The effect of a jasmonic acid derivative, tetra-hydro-jasmonic acid (LR2412, 1 and 10 μm) was investigated on an in vitro reconstructed skin model, Episkin™. Using real time RTQPCR studies, results showed an increase in hyaluronan synthase 2 (HAS2) and hyaluronase synthase 3 (HAS3) expression. Furthermore, an increase in hyaluronic acid (HA) deposits in basal and suprabasal layers of the epidermis was observed. The percentage of positive Ki67 keratinocytes in the basal layer as well as the epidermis thickness were seen to increase. Immunohistochemistry studies showed that the synthesis of late differentiation proteins filaggrin and transglutaminase 1 was not modified. The human epidermis is known to thin with age while HA content has been reported to decrease. These results illustrate the potential of LR2412 in counteracting signs of skin ageing.

  16. Lithospheric controls on late Cenozoic construction of the Mongolian Altai

    NASA Astrophysics Data System (ADS)

    Cunningham, W. Dickson

    1998-12-01

    The Altai is one of the great Cenozoic intracontinental and intraplate mountain ranges of central Asia, but it is one of the less studied mountain belts on Earth from a modern structural geology standpoint, and few western scientists are familiar with its tectonic evolution. The range is located dominantly in Mongolia with important sectors in Russia, China, and Kazakhstan and structurally links with the Chinese Tien Shan and Russian Sayan ranges. The Altai is tectonically active and is best understood as two kinematically distinct mountain belts that intersect at 46°N, 96°E: the right-lateral transpressive western Altai and the left-lateral transpressive Gobi Altai. Transpressional deformation dominates the late Cenozoic deformation of the Altai and is manifested by throughgoing strike-slip faults, restraining bends, thrust fault-bounded ranges linked by strike-slip faults, and possibly inverted Mesozoic graben. Regionally, there is strong correlation between Cenozoic fault trends and older basement strike trends. Cenozoic deformation regimes appear to be dictated by the angular relationship between preexisting basement structural trends and the prevailing NE directed maximum compressive stress. The Altai is constructed on Paleozoic terranes dominantly consisting of arc and subduction complex assemblages and passive margin sedimentary rocks juxtaposed to the west, southwest and south of the Precambrian block that underlies the Hangay Dome area of central Mongolia. Because the Hangay Dome is characterized by diffuse extension and not transpression, regionally upwarped topography, late Cenozoic volcanism, and elevated heat flow, it is kinematically separate from the Altai region and has previously been interpreted to overlie a mantle plume or asthenospheric diapir. It is proposed that anomalously hot mantle beneath the Hangay Dome coupled with the regionally domed surface topography creates a radial horizontal stress field that acts against the regional NE

  17. Leucine aminopeptidase regulates defense and wound signaling in tomato downstream of jasmonic acid.

    PubMed

    Fowler, Jonathan H; Narváez-Vásquez, Javier; Aromdee, Dale N; Pautot, Véronique; Holzer, Frances M; Walling, Linda L

    2009-04-01

    Leucine aminopeptidase A (LapA) is a late wound-response gene of tomato (Solanum lycopersicum). To elucidate the role of LapA, transgenic plants that overexpressed or abolished LapA gene expression were used. The early wound-response gene RNA levels were similar in wild-type and Lap-silenced (LapA-SI), -antisense (LapA-AS), and -overexpressing (LapA-OX) plants. By contrast, late wound-response gene RNA levels and protection against Manduca sexta damage were influenced by LapA RNA and protein levels. While LapA-OX plants had elevated levels of LapA RNAs and protein, ectopic expression of LapA was not sufficient to induce Pin (Ser proteinase inhibitor) or PPO (polyphenol oxidase) transcripts in nonwounded leaves. M. sexta larvae damaged less foliage and displayed delays in growth and development when feeding on LapA-OX plants. By contrast, LapA-SI and LapA-AS lines had lower levels of Pin and PPO RNAs than wild-type controls. Furthermore, larvae consumed more foliage and attained larger masses when feeding on LapA-SI plants. Jasmonic acid (JA) did not complement the wound-signaling phenotype of LapA-SI plants. Based on root elongation in the presence of JA, JA perception appeared to be intact in LapA-SI lines. Collectively, these data suggested that LAP-A has a role in modulating essential defenses against herbivores by promoting late wound responses and acting downstream of JA biosynthesis and perception.

  18. Leucine Aminopeptidase Regulates Defense and Wound Signaling in Tomato Downstream of Jasmonic Acid[W

    PubMed Central

    Fowler, Jonathan H.; Narváez-Vásquez, Javier; Aromdee, Dale N.; Pautot, Véronique; Holzer, Frances M.; Walling, Linda L.

    2009-01-01

    Leucine aminopeptidase A (LapA) is a late wound-response gene of tomato (Solanum lycopersicum). To elucidate the role of LapA, transgenic plants that overexpressed or abolished LapA gene expression were used. The early wound-response gene RNA levels were similar in wild-type and Lap-silenced (LapA-SI), -antisense (LapA-AS), and -overexpressing (LapA-OX) plants. By contrast, late wound-response gene RNA levels and protection against Manduca sexta damage were influenced by LapA RNA and protein levels. While LapA-OX plants had elevated levels of LapA RNAs and protein, ectopic expression of LapA was not sufficient to induce Pin (Ser proteinase inhibitor) or PPO (polyphenol oxidase) transcripts in nonwounded leaves. M. sexta larvae damaged less foliage and displayed delays in growth and development when feeding on LapA-OX plants. By contrast, LapA-SI and LapA-AS lines had lower levels of Pin and PPO RNAs than wild-type controls. Furthermore, larvae consumed more foliage and attained larger masses when feeding on LapA-SI plants. Jasmonic acid (JA) did not complement the wound-signaling phenotype of LapA-SI plants. Based on root elongation in the presence of JA, JA perception appeared to be intact in LapA-SI lines. Collectively, these data suggested that LAP-A has a role in modulating essential defenses against herbivores by promoting late wound responses and acting downstream of JA biosynthesis and perception. PMID:19376935

  19. Methyl jasmonate induction of tanshinone biosynthesis in Salvia miltiorrhiza hairy roots is mediated by JASMONATE ZIM-DOMAIN repressor proteins

    PubMed Central

    Shi, Min; Zhou, Wei; Zhang, Jianlin; Huang, Shengxiong; Wang, Huizhong; Kai, Guoyin

    2016-01-01

    Jasmonic acid (JA) is an important plant hormone involved in regulation of many aspects of plant growth and development including secondary metabolism and JASMONATE ZIM-DOMAIN (JAZ) proteins are key components in JA signal processes. In this study, two new JAZ genes named SmJAZ3 and SmJAZ9 were cloned from S. miltiorrhiza hairy roots and characterized. Expression profiles under methyl jasmonate (MJ) treatment revealed that SmJAZ3 and SmJAZ9 were both MJ-responsive. Subcellular localization assay showed that SmJAZ3 was located in nucleus while SmJAZ9 was preferentially in nucleus. Expression of SmJAZ3 and SmJAZ9 in S. miltiorrhiza hairy roots differently affected the production of tanshinone. Over-expression of SmJAZ3 or SmJAZ9 in hairy roots produced lower level of tanshinone compared with the control, tanshinone production was as low as 0.077 mg/g DW in line SmJAZ3-3 and 0.266 mg/g DW in line SmJAZ9-22. Whereas, down-regulation of SmJAZs enhanced tanshione production, the content of tanshinone increased to 2.48 fold in anti-SmJAZ3-3 line, and 1.35-fold in anti-SmJAZ9-23 line. Our work indicated that SmJAZ3 and SmJAZ9 are involved in regulation of tanshinone biosynthesis and act as repressive transcriptional regulators in the JA signaling pathway, which paves the way to further dissect molecular mechanism in details in the future. PMID:26875847

  20. Methyl jasmonate induction of tanshinone biosynthesis in Salvia miltiorrhiza hairy roots is mediated by JASMONATE ZIM-DOMAIN repressor proteins.

    PubMed

    Shi, Min; Zhou, Wei; Zhang, Jianlin; Huang, Shengxiong; Wang, Huizhong; Kai, Guoyin

    2016-02-15

    Jasmonic acid (JA) is an important plant hormone involved in regulation of many aspects of plant growth and development including secondary metabolism and JASMONATE ZIM-DOMAIN (JAZ) proteins are key components in JA signal processes. In this study, two new JAZ genes named SmJAZ3 and SmJAZ9 were cloned from S. miltiorrhiza hairy roots and characterized. Expression profiles under methyl jasmonate (MJ) treatment revealed that SmJAZ3 and SmJAZ9 were both MJ-responsive. Subcellular localization assay showed that SmJAZ3 was located in nucleus while SmJAZ9 was preferentially in nucleus. Expression of SmJAZ3 and SmJAZ9 in S. miltiorrhiza hairy roots differently affected the production of tanshinone. Over-expression of SmJAZ3 or SmJAZ9 in hairy roots produced lower level of tanshinone compared with the control, tanshinone production was as low as 0.077 mg/g DW in line SmJAZ3-3 and 0.266 mg/g DW in line SmJAZ9-22. Whereas, down-regulation of SmJAZs enhanced tanshione production, the content of tanshinone increased to 2.48 fold in anti-SmJAZ3-3 line, and 1.35-fold in anti-SmJAZ9-23 line. Our work indicated that SmJAZ3 and SmJAZ9 are involved in regulation of tanshinone biosynthesis and act as repressive transcriptional regulators in the JA signaling pathway, which paves the way to further dissect molecular mechanism in details in the future.

  1. Sense of control in late life: health and survival implications.

    PubMed

    Chipperfield, Judith G; Newall, Nancy E; Perry, Raymond P; Stewart, Tara L; Bailis, Daniel S; Ruthig, Joelle C

    2012-08-01

    Believing that one can influence outcomes presumably fosters a psychological sense of control. So too, however, might adaptive ways of thinking known as secondary control (SC) processes that operate when outcomes are believed to be unattainable. Using a 5-year prospective design and a representative sample of adults (ages 79-98), folk beliefs (e.g., "negative experiences can be a blessing in disguise") were used to assess SC processes. The authors expected SC Folk Beliefs would predict Sense of Control (Hypothesis 1) which, in turn, would predict self-rated health, hospital admissions, and survival (Hypothesis 2). An indirect relationship was hypothesized: SC Folk Beliefs were expected to predict outcomes through the Sense of Control (Hypothesis 3). Support was found for all hypotheses providing insights into the antecedents and consequences of a sense of control and about how SC beliefs and a sense of control function in the context of health.

  2. Porosity controls in Late Jurassic algal reefs, Mississippi salt basin

    SciTech Connect

    Heydari, E.; Moore, C.H.

    1987-05-01

    Reefs associated with high-rise salt structures that were active during Late Jurassic deposition (Smackover-Haynesville) have been the target of numerous deep tests in the Mississippi Salt basin. One such test, in Wayne County, Mississippi, encountered a 24-m reef. The reef exhibited no porosity or permeability, while sequences above (21 m) and below (24 m) were dolomitized, porous, and permeable. The reef sequence consists of a facies mosaic of encrusting to columnar massive red coralline algae, laminated to stromatolitic blue-green algae(.) with associated pelleted internal sediments and other features characteristic of modern framework reefs. The reef complex exhibits a strong early marine diagenetic overprint consisting of bladed to fibrous magnesian calcite(.) cements and botryoidal masses of magnesian calcite or aragonite. The lack of discernible freshwater diagenesis and the nature of the reef framework seem to indicate deeper water conditions for reef development and subsequent early diagenesis. The associated dolomites have relict texture indicating that they were originally grainstones, perhaps derived from the reef itself. In the reef sequence, the geologic setting (relatively deep water), early marine cementation, and encrusting nature of the reef-formers produced a non-porous rock which was not susceptible to early dolomitization. However, the associated porous grainstones allowed active circulation of dolomitizing fluids (marine water.), leading to total dolomitization and a favorable reservoir facies.

  3. Jasmonic acid signaling modulates ozone-induced hypersensitive cell death.

    PubMed

    Rao, M V; Lee, H; Creelman, R A; Mullet, J E; Davis, K R

    2000-09-01

    Recent studies suggest that cross-talk between salicylic acid (SA)-, jasmonic acid (JA)-, and ethylene-dependent signaling pathways regulates plant responses to both abiotic and biotic stress factors. Earlier studies demonstrated that ozone (O(3)) exposure activates a hypersensitive response (HR)-like cell death pathway in the Arabidopsis ecotype Cvi-0. We now have confirmed the role of SA and JA signaling in influencing O(3)-induced cell death. Expression of salicylate hydroxylase (NahG) in Cvi-0 reduced O(3)-induced cell death. Methyl jasmonate (Me-JA) pretreatment of Cvi-0 decreased O(3)-induced H(2)O(2) content and SA concentrations and completely abolished O(3)-induced cell death. Cvi-0 synthesized as much JA as did Col-0 in response to O(3) exposure but exhibited much less sensitivity to exogenous Me-JA. Analyses of the responses to O(3) of the JA-signaling mutants jar1 and fad3/7/8 also demonstrated an antagonistic relationship between JA- and SA-signaling pathways in controlling the magnitude of O(3)-induced HR-like cell death.

  4. Manipulating anthocyanin composition in Vitis vinifera suspension cultures by elicitation with jasmonic acid and light irradiation.

    PubMed

    Curtin, Chris; Zhang, Wei; Franco, Chris

    2003-07-01

    Jasmonic acid altered the accumulation of major anthocyanins in Vitis vinifera cell culture. Peonidin 3-glucoside content at day three was increased from 0.3 to 1.7 mg g(-1) dry cell wt while other major anthocyanins were increased by smaller increments. By day 14, the content of methylated and acylated anthocyanins (peonidin 3-p-coumaroylglucoside and malvidin 3-p-coumaroylglucoside) was 6.3 mg g(-1) DCW, in response to treatment with jasmonic acid, and comprising approximately 45% (w/w) of total anthocyanins. In comparison, the untreated control culture contained 1.2 mg g(-1) DCW which made up approximately 32% (w/w) of total anthocyanins. Light further enhanced anthocyanin accumulation induced by jasmonic acid elicitation. The content of peonidin 3-glucoside at day 3 was 6.6 mg g(-1) DCW, 22-fold higher than control cultures while the content in response to light irradiation alone was 0.6 mg g(-1) DCW. When a highly pigmented cell line was elicited with jasmonic acid total anthocyanins increased from 9.2 to 20.7 mg g(-1) DCW, but there was no change in the anthocyanin composition.

  5. Fragrance material review on cis-jasmone.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-10-01

    A toxicologic and dermatologic review of cis-jasmone when used as a fragrance ingredient is presented. cis-Jasmone is a member of the fragrance structural group ketones cyclopentanones and cyclopentenones. The common characteristic structural element of the group members is a cyclopentanone or cyclopentenone ring with a straight or branched chain alkane or alkene substituent. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for cis-jasmone were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, phototoxicity, photoallergy, and genotoxicity data. A safety assessment of the entire ketones cyclopentanones and cyclopentenones will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all ketones cyclopentanones and cyclopentenones in fragrances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Fragrance material review on methyl jasmonate.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-10-01

    A toxicologic and dermatologic review of methyl jasmonate when used as a fragrance ingredient is presented. Methyl jasmonate is a member of the fragrance structural group Ketones Cyclopentanones and Cyclopentenones. The common characteristic structural element of the group members is a cyclopentanone or cyclopentenone ring with a straight or branched chain alkane or alkene substituent. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for methyl jasmonate were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, phototoxicity, and photoallergy data. A safety assessment of the entire Ketones Cyclopentanones and Cyclopentenones will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Ketones Cyclopentanones and Cyclopentenones in fragrances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Late presentation of acromegaly in medically controlled prolactinoma patients

    PubMed Central

    Manuylova, Ekaterina; Calvi, Laura M; Hastings, Catherine; Vates, G Edward; Johnson, Mahlon D; Cave, William T

    2016-01-01

    Summary Co-secretion of growth hormone (GH) and prolactin (PRL) from a single pituitary adenoma is common. In fact, up to 25% of patients with acromegaly may have PRL co-secretion. The prevalence of acromegaly among patients with a newly diagnosed prolactinoma is unknown. Given the possibility of mixed GH and PRL co-secretion, the current recommendation is to obtain an insulin-like growth factor-1 (IGF-1) in patients with prolactinoma at the initial diagnosis. Long-term follow-up of IGF-1 is not routinely done. Here, we report two cases of well-controlled prolactinoma on dopamine agonists with the development of acromegaly 10–20 years after the initial diagnoses. In both patients, a mixed PRL/GH-cosecreting adenoma was confirmed on the pathology examination after transsphenoidal surgery (TSS). Therefore, periodic routine measurements of IGF-1 should be considered regardless of the duration and biochemical control of prolactinoma. Learning points: Acromegaly can develop in patients with well-controlled prolactinoma on dopamine agonists. The interval between prolactinoma and acromegaly diagnoses can be several decades. Periodic screening of patients with prolactinoma for growth hormone excess should be considered and can 
lead to an early diagnosis of acromegaly before the development of complications. PMID:27855229

  8. Bacteriophage Nf DNA region controlling late transcription: structural and functional homology with bacteriophage phi 29.

    PubMed

    Nuez, B; Salas, M

    1993-06-25

    The putative region for the control of late transcription of the Bacillus subtilis phage Nf has been identified by DNA sequence homology with the equivalent region of the evolutionary related phage phi 29. A similar arrangement of early and late promoters has been detected in the two phages, suggesting that viral transcription could be regulated in a similar way at late times of the infection. Transcription of late genes requires the presence of a viral early protein, gpF in phage Nf and p4 in phage phi 29, being the latter known to bind to a DNA region located upstream from the phage phi 29 late promoter. We have identified a DNA region located upstream from the putative late promoter of phage Nf that is probably involved in binding protein gpF. Furthermore, we show that the phage phi 29 protein p4 is able to bind to this region and activate transcription from the phage Nf putative late promoter. Sequence alignment has also revealed the existence of significant internal homology between the two early promoters contained in this region of each phage.

  9. [Genetic screening and analysis of suppressors of asa1-1 (soa) defective in jasmonate-mediated lateral root formation in Arabidopsis].

    PubMed

    Li, Yan-An; Qi, Lin-Lin; Sun, Jia-Qiang; Liu, Hong-Yu; Li, Chuan-You

    2011-09-01

    It has been shown that jasmonate modulates the lateral root development through crosstalk with auxin in Arabidopsis thaliana. Exogenous application of jasmonate stimulates lateral root formation in wild type but inhibits lateral root formation in asa1-1. Our previous work has demonstrated that the lateral root formation defect of asa1-1 is co-related with jasmonte effect on PIN2 protein levels. To further elucidate the molecular mechanisms underlying jasmonate-mediated reduction of plasma membrane (PM)-resident PIN2 abundance, we have conducted a genetic screen to identify suppressors of asa1-1 (soa), which showed lateral root formation in the presence of jasmonate. Here, we described the basic characterization of soa563 and soa856. We showed that both soa563 and soa856 displayed restored lateral root formation in response to exogenous jasmonate. In addition, jasmonate-induced PIN2:GFP reduction was blocked in these two mutants. Our on-going effort to identify genes defined by these mutants promise to shed new light on the understanding of the molecular mechanisms controlling jasmonate-mediated regulation of PIN2 protein trafficking and turnover.

  10. [Content of Osmolytes and Flavonoids under Salt Stress in Arabidopsis thaliana Plants Defective in Jasmonate Signaling].

    PubMed

    Yastreb, T O; Kolupaev, Yu E; Lugovaya, A A; Dmitriev, A P

    2016-01-01

    The effects of the salt stress (200 mM NaCl) and exogenous jasmonic acid (JA) on levels of osmolytes and flavonoids in leaves of four-week-old Arabidopsis thaliana L. plants of the wild-type (WT) Columbia-0 (Col-0) and the mutant jin1 (jasmonate insensitive 1) with impaired jasmonate signaling were studied. The increase in proline content caused by the salt stress was higher in the Col-0 plants than in the mutant jin1. This difference was especially marked if the plants had been pretreated with exogenous 0.1 µM JA. The sugar content increased in response to the salt stress in the JA-treated WT plants but decreased in the jin1 mutant. Leaf treatment with JA of the WT plants but not mutant defective in jasmonate signaling also enhanced the levels of anthocyanins and flavonoids absorbed in UV-B range. The presence of JA increased salinity resistance of the Col-0 plants, since the accumulation of lipid peroxidation products and growth inhibition caused by NaCl were less pronounced. Under salt stress, JA almost did not render a positive effect on the jin1 plants. It is concluded that the protein JIN1/MYC2 is involved in control of protective systems under salt stress.

  11. Jasmonic acid-dependent regulation of seed dormancy following maternal herbivory in Arabidopsis.

    PubMed

    Singh, Prashant; Dave, Anuja; Vaistij, Fabian E; Worrall, Dawn; Holroyd, Geoff H; Wells, Jonathan G; Kaminski, Filip; Graham, Ian A; Roberts, Michael R

    2017-06-01

    Maternal experience of abiotic environmental factors such as temperature and light are well known to control seed dormancy in many plant species. Maternal biotic stress alters offspring defence phenotypes, but whether it also affects seed dormancy remains unexplored. We exposed Arabidopsis thaliana plants to herbivory and investigated plasticity in germination and defence phenotypes in their offspring, along with the roles of phytohormone signalling in regulating maternal effects. Maternal herbivory resulted in the accumulation of jasmonic acid-isoleucine and loss of dormancy in seeds of stressed plants. Dormancy was also reduced by engineering seed-specific accumulation of jasmonic acid in transgenic plants. Loss of dormancy was dependent on an intact jasmonate signalling pathway and was associated with increased gibberellin content and reduced abscisic acid sensitivity during germination. Altered dormancy was only observed in the first generation following herbivory, whereas defence priming was maintained for at least two generations. Herbivory generates a jasmonic acid-dependent reduction in seed dormancy, mediated by alteration of gibberellin and abscisic acid signalling. This is a direct maternal effect, operating independently from transgenerational herbivore resistance priming. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  12. Exogenous jasmonic acid induces stress tolerance in tobacco (Nicotiana tabacum) exposed to imazapic.

    PubMed

    Kaya, Armagan; Doganlar, Zeynep Banu

    2016-02-01

    Jasmonic acid (JA) is one of the important phytohormones, regulating the stress responses as well as plant growth and development. The aim of this study is to determine the effects of exogenous JA application on stress responses of tobacco plant exposed to imazapic. In this study, phytotoxic responses resulting from both imazapic and imazapic combined with JA treatment are investigated comparatively for tobacco plants. For plants treated with imazapic at different concentrations (0.030, 0.060 and 0.120mM), antioxidant enzyme activities (catalase, ascorbate peroxidase, glutathione S-transferase and glutathione reductase), carotenoids, glutathione and malondialdehyte (MDA) contents, jasmonic acid, abscisic acid and indole-3-acetic acid levels as well as herbicide residue amounts on leaves increased in general compared to the control group. In the plants treated with 45µM jasmonic acid, pigment content, antioxidant activity and phytohormone level increased whereas MDA content and the amount of herbicidal residue decreased compared to the non-treated plants. Our findings show that imazapic treatment induces some phytotoxic responses on tobacco leaves and that exogenous jasmonic acid treatment alleviates the negative effects of herbicide treatment by regulating these responses. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Nematocidal effects of natural phytoregulators jasmonic acid and methyl-jasmonate against Pratylenchus zeae and Helicotylenchus spp.

    PubMed

    Gavin, Amanda Salomão; Faggion, Silmara Aparecida; Hernandes, Camila; Lourenço, Mirian Vergínia; França, Suzelei de Castro; Beleboni, Rene Oliveira

    2013-01-01

    The aim of this study was to evaluate the nematocidal effects of natural phytoregulators jasmonic acid (JA) and methyl-jasmonate (MJ) against plant parasitic nematodes Pratylenchus zeae (Graham) (Pratylenchidae) and Helicotylenchus spp. (Hoplolaimidae). Both JA and MJ promoted elevated percentages of mortality in P. zeae and Helicotylenchus spp. after 12 and 24 h of nematodes exposition at different concentrations of jasmonates. Considering the potential use of jasmonates as biofertiliser added now for their nematocidal effects, our results are of relevance in terms of biotechnological application.

  14. Roles of jasmonate signalling in plant inflorescence and flower development.

    PubMed

    Yuan, Zheng; Zhang, Dabing

    2015-10-01

    Development of inflorescences and flowers in plants is controlled by the combined action of environmental and genetic signals. Investigations reveal that the phytohormone jasmonate (JA) plays a critical function in plant reproduction such as male fertility, sex determination and seed maturation. Here, we review recent progress on JA synthesis, signalling, the interplay between JAs and other hormones, and regulatory network of JA in controlling the development of inflorescence, flower and the male organ. The conserved and diversified roles of JAs in meristem transition and specification of flower organ identity and number, and multiple regulatory networks of JAs in stamen development are highlighted. Further, this review provides perspectives on future research endeavors to elucidate mechanisms underlying JAs homeostasis and transport during plant reproductive development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Social control and strenuous exercise among late adolescent college students: parents versus peers as influence agents.

    PubMed

    Pugliese, John A; Okun, Morris A

    2014-07-01

    In the context of a model of health-related social control, we compared the associations among social control strategies, affective and behavioral reactions, and exercise for parental and peer influence agents. Late adolescent college students (n = 227) completed questionnaires that focused on social control from a parent or a peer who attempted to increase their exercising. Results from this cross-sectional study revealed that most relationships in the model were similar for parent and peer influence agents, however, (a) negative social control was a stronger predictor of reactance among parents than peers; (b) positive affect was a stronger predictor of attempts to change among peers than parents; and (c) positive affect predicted frequency of strenuous exercise only among parents. Decreasing parents' use of negative social control strategies and increasing adolescents' positive affective reactions to parental social control agents may be keys to promoting positive lifestyle changes in late adolescence.

  16. Jasmonates act positively in adventitious root formation in petunia cuttings.

    PubMed

    Lischweski, Sandra; Muchow, Anne; Guthörl, Daniela; Hause, Bettina

    2015-09-22

    Petunia is a model to study the process of adventitious root (AR) formation on leafy cuttings. Excision of cuttings leads to a transient increase in jasmonates, which is regarded as an early, transient and critical event for rooting. Here, the role of jasmonates in AR formation on petunia cuttings has been studied by a reverse genetic approach. To reduce the endogenous levels of jasmonates, transgenic plants were generated expressing a Petunia hybrida ALLENE OXIDE CYCLASE (PhAOC)-RNAi construct. The transgenic plants exhibited strongly reduced PhAOC transcript and protein levels as well as diminished accumulation of cis-12-oxo-phytodienoic acid, jasmonic acid and jasmonoyl-isoleucine after wounding in comparison to wild type and empty vector expressing plants. Reduced levels of endogenous jasmonates resulted in formation of lower numbers of ARs. However, this effect was not accompanied by altered levels of auxin and aminocyclopropane carboxylate (ACC, precursor of ethylene) or by impaired auxin and ethylene-induced gene expression. Neither activity of cell-wall invertases nor accumulation of soluble sugars was altered by jasmonate deficiency. Diminished numbers of AR in JA-deficient cuttings suggest that jasmonates act as positive regulators of AR formation in petunia wild type. However, wound-induced rise in jasmonate levels in petunia wild type cuttings seems not to be causal for increased auxin and ethylene levels and for sink establishment.

  17. Effect of methyl jasmonate on sugarbeet yield and storage properties

    USDA-ARS?s Scientific Manuscript database

    Methyl jasmonate is an endogenous plant hormone that induces plant defense mechanisms against environmental stresses and pathogens. Applied exogenously, methyl jasmonate has been shown to provide protection against a wide array of pathogens and environmental stresses in a variety of crop plants and ...

  18. Effects of Light and Wounding on Jasmonates in Rice phyAphyC Mutants

    PubMed Central

    Brendel, Rita; Svyatyna, Katharina; Jikumaru, Yusuke; Reichelt, Michael; Mithöfer, Axel; Takano, Makoto; Kamiya, Yuji; Nick, Peter; Riemann, Michael

    2014-01-01

    Jasmonates (JA) are lipid-derived plant hormones. They have been shown to be important regulators of photomorphogenesis, a developmental program in plants, which is activated by light through different red and blue light sensitive photoreceptors. In rice, inhibition of coleoptile growth by light is a central event in photomorphogenesis. This growth inhibition is impaired, when jasmonate biosynthesis is knocked out. Previously, we found that JASMONATE RESISTANT 1 (OsJAR1) transcripts were not induced in the phytochrome (phy) mutant phyAphyC. Therefore, in the current study we investigated the regulation of JA and its highly bioactive derivative (+)-7-iso-jasmonoyl-l-isoleucine (JA-Ile), as well as the transcriptional regulation of several JA-dependent genes both in wild type and phyAphyC mutant. JA and JA-Ile levels increased in the mutant seedlings in response to blue light. However, in phyAphyC mutant leaves, which were continuously wounded, JA and JA-Ile levels were lower compared to those in the wild type. Hence, the mutation of phyA and phyC has differential effects on jasmonate levels depending on the tissue and developmental stage. Our results suggest that the contribution of JA-Ile to signaling during photomorphogenesis of rice is minor, as coleoptile phenotypes of phyAphyC mutants resemble those of jasmonate-deficient mutants despite the fact that induction by blue light leads to higher levels of JA-Ile compared to the wild type. We postulate that phyA and phyC could control the activity of specific enzymes metabolizing JA to active derivatives. PMID:27135497

  19. Defense signaling among interconnected ramets of a rhizomatous clonal plant, induced by jasmonic-acid application

    NASA Astrophysics Data System (ADS)

    Chen, Jin-Song; Lei, Ning-Fei; Liu, Qing

    2011-07-01

    Resource sharing between ramets of clonal plants is a well-known phenomenon that allows stoloniferous and rhizomatous species to internally transport water, mineral nutrients and carbohydrates from sites of high supply to sites of high demand. Moreover, vascular ramet connections are likely to provide an excellent means to share substances other than resources, such as defense signals. In a greenhouse experiment, the rhizomatous sedge Carex alrofusca, consisting of integrated ramets of different ages, was used to study the transmission of defense signals through belowground rhizome connections in response to local spray with jasmonic-acid. A feeding preference test with the caterpillar Gynaephora rnenyuanensis was employed to assess benefits of rhizome connections on defense signaling. Young ramets were more responsive to jasmonic-acid treatment than middle-aged or old ramets. Condensed tannin content in the foliage of young ramets showed a significant increase and soluble carbohydrate and nitrogen content showed marginally significant decreases in the 1 mM jasmonic-acid treatment but not in control and/or 0.0001 mM jasmonic-acid treatments. The caterpillar G. rnenyuanensis preferentially grazed young ramets. After a localized spray of 1 mM jasmonic-acid, the leaf area of young ramets consumed by herbivores was greatly reduced. We propose that defense signals may be transmitted through physical connections (stolon or rhizome) among interconnected ramets of clonal plants. Induced resistance to herbivory may selectively enhance the protection of more vulnerable and valuable plant tissues and confer a significant benefit to clonal plants by a modular risk-spreading strategy, equalizing ontogenetic differences of unevenly-aged ramets in chemical defense compounds and nutritional properties of tissue.

  20. Jasmonates: Multifunctional Roles in Stress Tolerance

    PubMed Central

    Ahmad, Parvaiz; Rasool, Saiema; Gul, Alvina; Sheikh, Subzar A.; Akram, Nudrat A.; Ashraf, Muhammad; Kazi, A. M.; Gucel, Salih

    2016-01-01

    Jasmonates (JAs) [Jasmonic acid (JA) and methyl jasmonates (MeJAs)] are known to take part in various physiological processes. Exogenous application of JAs so far tested on different plants under abiotic stresses particularly salinity, drought, and temperature (low/high) conditions have proved effective in improving plant stress tolerance. However, its extent of effectiveness entirely depends on the type of plant species tested or its concentration. The effects of introgression or silencing of different JA- and Me-JA-related genes have been summarized in this review, which have shown a substantial role in improving crop yield and quality in different plants under stress or non-stress conditions. Regulation of JAs synthesis is impaired in stressed as well as unstressed plant cells/tissues, which is believed to be associated with a variety of metabolic events including signal transduction. Although, mitogen activated protein kinases (MAPKs) are important components of JA signaling and biosynthesis pathways, nitric oxide, ROS, calcium, ABA, ethylene, and salicylic acid are also important mediators of plant growth and development during JA signal transduction and synthesis. The exploration of other signaling molecules can be beneficial to examine the details of underlying molecular mechanisms of JA signal transduction. Much work is to be done in near future to find the proper answers of the questions like action of JA related metabolites, and identification of universal JA receptors etc. Complete signaling pathways involving MAPKs, CDPK, TGA, SIPK, WIPK, and WRKY transcription factors are yet to be investigated to understand the complete mechanism of action of JAs. PMID:27379115

  1. How Microbes Twist Jasmonate Signaling around Their Little Fingers

    PubMed Central

    Gimenez-Ibanez, Selena; Chini, Andrea; Solano, Roberto

    2016-01-01

    Plant immunity relies on a complex network of hormone signaling pathways in which jasmonic acid (JA) plays a central role. Successful microbial pathogens or symbionts have developed strategies to manipulate plant hormone signaling pathways to cause hormonal imbalances for their own benefit. These strategies include the production of plant hormones, phytohormone mimics, or effector proteins that target host components to disrupt hormonal signaling pathways and enhance virulence. Here, we describe the molecular details of the most recent and best-characterized examples of specific JA hormonal manipulation by microbes, which exemplify the ingenious ways by which pathogens can take control over the plant’s hormone signaling network to suppress host immunity. PMID:27135229

  2. Jasmonate signaling and manipulation by pathogens and insects.

    PubMed

    Zhang, Li; Zhang, Feng; Melotto, Maeli; Yao, Jian; He, Sheng Yang

    2017-01-09

    Plants synthesize jasmonates (JAs) in response to developmental cues or environmental stresses, in order to coordinate plant growth, development or defense against pathogens and herbivores. Perception of pathogen or herbivore attack promotes synthesis of jasmonoyl-L-isoleucine (JA-Ile), which binds to the COI1-JAZ receptor, triggering the degradation of JAZ repressors and induction of transcriptional reprogramming associated with plant defense. Interestingly, some virulent pathogens have evolved various strategies to manipulate JA signaling to facilitate their exploitation of plant hosts. In this review, we focus on recent advances in understanding the mechanism underlying the enigmatic switch between transcriptional repression and hormone-dependent transcriptional activation of JA signaling. We also discuss various strategies used by pathogens and insects to manipulate JA signaling and how interfering with this could be used as a novel means of disease control.

  3. Stress in Fathers of Moderately and Late Preterm Infants: A Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Ravn, Ingrid Helen; Lindemann, Rolf; Smeby, Nina Aarhus; Bunch, Eli Haugen; Sandvik, Leiv; Smith, Lars

    2012-01-01

    The atypical behaviour of preterm infants can elicit stress in fathers and influence their ability to perceive and interpret infants' cues. This study investigated whether fathers of moderately and late preterm infants were more stressed than fathers of term infants. In a randomised controlled trial, we also studied the effect of the Mother-Infant…

  4. Problem solving, impulse control and planning in patients with early- and late-stage Huntington's disease.

    PubMed

    Mörkl, Sabrina; Müller, Nicole J; Blesl, Claudia; Wilkinson, Leonora; Tmava, Adelina; Wurm, Walter; Holl, Anna K; Painold, Annamaria

    2016-10-01

    Sub-domains of executive functions, including problems with planning, accuracy, impulsivity, and inhibition, are core features of Huntington's disease. It is known that the decline of cognitive function in Huntington's disease is related to the anatomical progression of pathology in the basal ganglia. However, it remains to be determined whether the severity of executive dysfunction depends on the stage of the disease. To examine the severity of sub-domains of executive dysfunction in early- and late-stage Huntington's disease, we studied performance in the Tower of London task of two groups of Huntington's disease patients (Group 1: early, n = 23, and Group 2: late stage, n = 29), as well as a third group of age, education, and IQ matched healthy controls (n = 34). During the task, we measured the total number of problems solved, total planning time, and total number of breaks taken. One aspect of executive function indexed by the number of solved problems seems to progress in the course of the disease. Late-stage Huntington's disease patients scored significantly worse than early-stage patients and controls, and early-stage patients scored significantly worse than controls on this measure of accuracy. In contrast, late- and early-stage HD patients did not differ in terms of planning time and number of breaks. Early- and late-stage HD pathology has a different impact on executive sub-domains. While accuracy differs between early- and late-stage HD patients, other domains like planning time and number of breaks do not. Striatal degeneration, which is a characteristic feature of the disease, might not affect all aspects of executive function in HD.

  5. Attraction of New Zealand flower thrips, Thrips obscuratus, to cis-jasmone, a volatile identified from Japanese honeysuckle flowers.

    PubMed

    El-Sayed, A M; Mitchell, V J; McLaren, G F; Manning, L M; Bunn, B; Suckling, D M

    2009-06-01

    This work was undertaken to identify floral compound(s) produced by honeysuckle flowers, Lonicera japonica (Thunberg), that mediate the attraction of New Zealand flower thrips Thrips obscuratus (Crawford). Volatiles were collected during the day and night and analyzed by gas chromatography-mass spectrometry (GC-MS) to determine their emission over these two periods. Nine compounds were identified in the headspace; the main compound was linalool, and the other compounds were germacrene D, E,E-alpha-farnesene, nerolidol, cis-jasmone, cis-3-hexenyl acetate, hexyl acetate, cis-hexenyl tiglate, and indole. There was a quantitative difference between day and night volatiles, with cis-3-hexenyl acetate, hexyl acetate, cis-hexenyl tiglate, and cis-jasmone emitted in higher amounts during the day compared to the night. When the compounds were tested individually in field trapping experiments, only cis-jasmone attracted New Zealand flower thrips in a significant number. In another field trapping experiment, cis-jasmone caught similar numbers of New Zealand flower thrips compared to a floral blend formulated to mimic the ratios of the compounds emitted during the day, while catch with the night-emitted floral blend was not significantly different from the control. Subsequently, two field trapping experiments were conducted to determine the optimal attraction dose for cis-jasmone, a range of 1-100 mg loaded onto a red rubber stopper was tested, and the highest catches were in traps baited with 100 mg loading. A higher range of 100-1000 mg loaded into polyethylene vials was tested, and the highest catch was in traps baited with 500 mg. In another experiment aimed at comparing the attraction efficacy of cis-jasmone with the two other known thrips attractants (ethyl nicotinate and p-anisaldehyde), ethyl nicotinate showed the highest trap catch followed by cis-jasmone. A smaller number of Thrips tabaci (Lindeman) was attracted to traps baited with cis-jasmone. These results

  6. Jasmonate signalling: a copycat of auxin signalling?

    PubMed

    Pérez, A Cuéllar; Goossens, A

    2013-12-01

    Plant hormones regulate almost all aspects of plant growth and development. The past decade has provided breakthrough discoveries in phytohormone sensing and signal transduction, and highlighted the striking mechanistic similarities between the auxin and jasmonate (JA) signalling pathways. Perception of auxin and JA involves the formation of co-receptor complexes in which hormone-specific E3-ubiquitin ligases of the SKP1-Cullin-F-box protein (SCF) type interact with specific repressor proteins. Across the plant kingdom, the Aux/IAA and the JASMONATE-ZIM DOMAIN (JAZ) proteins correspond to the auxin- and JA-specific repressors, respectively. In the absence of the hormones, these repressors form a complex with transcription factors (TFs) specific for both pathways. They also recruit several proteins, among which the general co-repressor TOPLESS, and thereby prevent the TFs from activating gene expression. The hormone-mediated interaction between the SCF and the repressors targets the latter for 26S proteasome-mediated degradation, which, in turn, releases the TFs to allow modulating hormone-dependent gene expression. In this review, we describe the similarities and differences in the auxin and JA signalling cascades with respect to the protein families and the protein domains involved in the formation of the pathway-specific complexes.

  7. Exogenous methyl jasmonate induces volatile emissions in cotton plants.

    PubMed

    Rodriguez-Saona, C; Crafts-Brandner, S J; Paré, P W; Henneberry, T J

    2001-04-01

    We investigated the effect of exogenous methyl jasmonate (MeJA) on the emission of herbivore-induced volatiles; these volatile chemicals can signal natural enemies of the herbivore to the damaged plant. Exogenous treatment of cotton cv. Deltapine 5415 plants with MeJA induced the emission of the same volatile compounds as observed for herbivore-damaged plants. Cotton plants treated with MeJA emitted elevated levels of the terpenes (E)-beta-ocimene, linalool, (3E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-alpha-farnesene, (E)-beta-farnesene, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene compared to untreated controls. Other induced components included (Z)-3-hexenyl acetate, methyl salicylate, and indole. Methyl jasmonate treatment did not cause the release of any of the stored terpenes such as alpha-pinene, beta-pinene, alpha-humulene, and (E)-beta-caryophyllene. In contrast, these compounds were emitted in relatively large amounts from cotton due to physical disruption of glands by the herbivores. The timing of volatile release from plants treated with MeJA or herbivores followed a diurnal pattern, with maximal volatile release during the middle of the photoperiod. Similar to herbivore-treated plants, MeJA treatment led to the systemic induction of (Z)-3-hexenyl acetate, (E)-beta-ocimene, linalool, (3E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-alpha-farnesene, (E)-beta-farnesene, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene. Our results indicate that treatment of cotton with MeJA can directly and systemically induce the emission of volatiles that may serve as odor cues in the host-search behavior of natural enemies.

  8. Ulvan, a sulfated polysaccharide from green algae, activates plant immunity through the jasmonic acid signaling pathway.

    PubMed

    Jaulneau, Valérie; Lafitte, Claude; Jacquet, Christophe; Fournier, Sylvie; Salamagne, Sylvie; Briand, Xavier; Esquerré-Tugayé, Marie-Thérèse; Dumas, Bernard

    2010-01-01

    The industrial use of elicitors as alternative tools for disease control needs the identification of abundant sources of them. We report on an elicitor obtained from the green algae Ulva spp. A fraction containing most exclusively the sulfated polysaccharide known as ulvan-induced expression of a GUS gene placed under the control of a lipoxygenase gene promoter. Gene expression profiling was performed upon ulvan treatments on Medicago truncatula and compared to phytohormone effects. Ulvan induced a gene expression signature similar to that observed upon methyl jasmonate treatment (MeJA). Involvement of jasmonic acid (JA) in ulvan response was confirmed by detecting induction of protease inhibitory activity and by hormonal profiling of JA, salicylic acid (SA) and abscisic acid (ABA). Ulvan activity on the hormonal pathway was further consolidated by using Arabidopsis hormonal mutants. Altogether, our results demonstrate that green algae are a potential reservoir of ulvan elicitor which acts through the JA pathway.

  9. Ulvan, a Sulfated Polysaccharide from Green Algae, Activates Plant Immunity through the Jasmonic Acid Signaling Pathway

    PubMed Central

    Jaulneau, Valérie; Lafitte, Claude; Jacquet, Christophe; Fournier, Sylvie; Salamagne, Sylvie; Briand, Xavier; Esquerré-Tugayé, Marie-Thérèse; Dumas, Bernard

    2010-01-01

    The industrial use of elicitors as alternative tools for disease control needs the identification of abundant sources of them. We report on an elicitor obtained from the green algae Ulva spp. A fraction containing most exclusively the sulfated polysaccharide known as ulvan-induced expression of a GUS gene placed under the control of a lipoxygenase gene promoter. Gene expression profiling was performed upon ulvan treatments on Medicago truncatula and compared to phytohormone effects. Ulvan induced a gene expression signature similar to that observed upon methyl jasmonate treatment (MeJA). Involvement of jasmonic acid (JA) in ulvan response was confirmed by detecting induction of protease inhibitory activity and by hormonal profiling of JA, salicylic acid (SA) and abscisic acid (ABA). Ulvan activity on the hormonal pathway was further consolidated by using Arabidopsis hormonal mutants. Altogether, our results demonstrate that green algae are a potential reservoir of ulvan elicitor which acts through the JA pathway. PMID:20445752

  10. Inhibitory effect of jasmonic acid and ethylene on epicotyl growth and bud induction in the maritime pine, Pinus pinaster Soland. in ait.

    PubMed

    Martin, Maria Teresa; Pedranzani, Hilda; García-Molinero, Patricia; Pando, Valentin; Sierra-de-Grado, Rosario

    2009-12-01

    Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatments with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.

  11. Jasmonate is essential for insect defense in Arabidopsis.

    PubMed

    McConn, M; Creelman, R A; Bell, E; Mullet, J E; Browse, J

    1997-05-13

    The signaling pathways that allow plants to mount defenses against chewing insects are known to be complex. To investigate the role of jasmonate in wound signaling in Arabidopsis and to test whether parallel or redundant pathways exist for insect defense, we have studied a mutant (fad3-2 fad7-2 fad8) that is deficient in the jasmonate precursor linolenic acid. Mutant plants contained negligible levels of jasmonate and showed extremely high mortality ( approximately 80%) from attack by larvae of a common saprophagous fungal gnat, Bradysia impatiens (Diptera: Sciaridae), even though neighboring wild-type plants were largely unaffected. Application of exogenous methyl jasmonate substantially protected the mutant plants and reduced mortality to approximately 12%. These experiments precisely define the role of jasmonate as being essential for the induction of biologically effective defense in this plant-insect interaction. The transcripts of three wound-responsive genes were shown not to be induced by wounding of mutant plants but the same transcripts could be induced by application of methyl jasmonate. By contrast, measurements of transcript levels for a gene encoding glutathione S-transferase demonstrated that wound induction of this gene is independent of jasmonate synthesis. These results indicate that the mutant will be a good genetic model for testing the practical effectiveness of candidate defense genes.

  12. Differences in grip force control between young and late middle-aged adults.

    PubMed

    Zheng, Lianrong; Li, Kunyang; Wang, Qian; Chen, Wenhui; Song, Rong; Liu, Guanzheng

    2017-08-22

    Grip force control is a crucial function for human to guarantee the quality of life. To examine the effects of age on grip force control, 10 young adults and 11 late middle-aged adults participated in visually guided tracking tasks using different target force levels (25, 50, and 75% of the subject's maximal grip force). Multiple measures were used to evaluate the tracking performance during force rising phase and force maintenance phase. The measurements include the rise time, fuzzy entropy, mean force percentage, coefficient of variation, and target deviation ratio. The results show that the maximal grip force was significantly lower in the late middle-aged adults than in the young adults. The time of rising phase was systematically longer among late middle-aged adults. The fuzzy entropy is a useful indicator for quantitating the force variability of the grip force signal at higher force levels. These results suggest that the late middle-aged adults applied a compensatory strategy that allow allows for sufficient time to reach the required grip force and reduce the impact of the early and subtle degenerative changes in hand motor function.

  13. Jasmonic acid/methyl jasmonate accumulate in wounded soybean hypocotyls and modulate wound gene expression.

    PubMed

    Creelman, R A; Tierney, M L; Mullet, J E

    1992-06-01

    Jasmonic acid (JA) and its methyl ester, methyl jasmonate (MeJA), are plant lipid derivatives that resemble mammalian eicosanoids in structure and biosynthesis. These compounds are proposed to play a role in plant wound and pathogen responses. Here we report the quantitative determination of JA/MeJA in planta by a procedure based on the use of [13C,2H3]MeJA as an internal standard. Wounded soybean (Glycine max [L] Merr. cv. Williams) stems rapidly accumulated MeJA and JA. Addition of MeJA to soybean suspension cultures also increased mRNA levels for three wound-responsive genes (chalcone synthase, vegetative storage protein, and proline-rich cell wall protein) suggesting a role for MeJA/JA in the mediation of several changes in gene expression associated with the plants' response to wounding.

  14. Tectonic control on the Late Quaternary hydrography of the Upper Tiber Basin (Northern Apennines, Italy)

    NASA Astrophysics Data System (ADS)

    Benvenuti, Marco; Bonini, Marco; Moroni, Adriana

    2016-09-01

    We examine the intramontane Upper Tiber Basin in the Northern Apennines (central Italy), where sub-orthogonal fault systems forced river deviation and the abandonment of alluvial fans since the late Middle Pleistocene. Archaeological material, spanning the Middle Palaeolithic-Iron Age, was collected mostly from the surface of the Late Quaternary alluvial landforms and related deposits (MUP and HOL units). This information contributed to the partial dating of seven major stages of drainage development. Normal faults parallel and transverse to the basin trend were active at different times and conditioned the valley pattern of the Middle (MUP1-2)-Late (MUP3) Pleistocene Tiber, Singerna, Sovara and Tignana rivers, which still flow today into the basin. The MUP1 and the MUP3 fans were beheaded by the displacement of their feeder valleys along the basin-transverse Carmine and Montedoglio faults. In some cases, the former feeder rivers underwent stream piracy but their courses mostly deviated in response of the topographic gradient created by faulting, as well as through the incision of new valleys that exploited the lithological contrast along the fault lines. The MUP3 Tignana fan was abandoned mostly due to the activity of the basin-parallel, dip-slip Sansepolcro fault. Subsidence driven by the basin-parallel Anghiari and Sansepolcro fault systems also provided the accommodation space for the MUP3 and HOl1-2 Afra fans between Late Pleistocene and early-mid Holocene. This study exemplifies the interplay between longitudinal and transverse fault systems, and the Late Quaternary hydrographic evolution of an extensional basin settled in the axial zone of an active fold-and-thrust belt. Although the faulting has interacted with the forcing exerted by the Late Quaternary climate fluctuations on the basin drainage systems, the tectonic rates are sufficiently high to represent the prime controller on base-level change and drainage routing patterns.

  15. Influence of methyl jasmonate on inducing chilling tolerance in pomegranate fruits (Malas Save).

    PubMed

    Zolfagharinasab, Rahim; Hadian, Javad

    2007-02-15

    Susceptibility to chilling injury in pomegranate is the main limiting factors for storage fruits in low temperature. Inducing chilling tolerance make possible to storage fruits in low temperature for long time. In this study effect of different concentrations of methyl jasmonate (8, 16 and 24 microL L(-1)) as comparison with control on inducing chilling tolerance of pomegranate fruits (Malas Save) was investigated. Qualitative attributes of treated fruits was investigated in different times during low temperature storage and also after transferring that to high temperature as a shelf life. The results showed that methyl jasmonate suppressed chilling injury and water loss and preserved external appearance in pomegranate fruits without abnormal effects on internal fruits quality. In general, with increasing methyl jasmonate concentration, fruits chilling injury reduced significantly. The highest chilling injury index was found in control fruits and the lowest one was for 24 microL L(-1) during storage in low temperature and also after placing in high temperature. Furthermore, no significant differences was found between treated and control fruits for internal fruit characteristics at end of storage.

  16. Host perception of jasmonates promotes infection by Fusarium oxysporum formae speciales that produce isoleucine- and leucine-conjugated jasmonates

    PubMed Central

    Cole, Stephanie J.; Yoon, Alexander J.; Faull, Kym F.; Diener, Andrew C.

    2014-01-01

    Summary Three pathogenic forms, or formae speciales, of Fusarium oxysporum infect the roots of Arabidopsis thaliana belowground, instigating symptoms of wilt disease in leaves aboveground. In prior reports, Arabidopsis mutants that are deficient in the biosynthesis of abscisic acid or salicylic acid or insensitive to ethylene or jasmonates exhibit more or less wilt disease than wild type, implicating the involvement of hormones in the normal host response to F. oxysporum. Our analysis of hormone-related mutants finds no evidence that endogenous hormones contribute to infection in roots. Mutants that are deficient in abscisic acid and insensitive to ethylene have no less infection than wild type, though they exhibit less disease. Whether a mutant that is insensitive to jasmonates affects infection depends on which forma specialis is infecting roots. Insensitivity to jasmonates suppresses infection by F. oxysporum forma specialis conglutinans and F. oxysporum forma specialis matthioli, which produce isoleucine- and leucine-conjugated jasmonate (JA-Ile/Leu) in culture filtrates; whereas, insensitivity to jasmonates has no effect on infection by F. oxysporum forma specialis raphani, which produces no detectable JA-Ile/Leu. Furthermore, insensitivity to jasmonates has no effect on wilt disease of tomato, and the tomato pathogen F. oxysporum forma specialis lycopersici produces no detectable jasmonates. Thus, some but not all F. oxysporum pathogens appear to utilize jasmonates as effectors, promoting infection in roots and/or development of symptoms in shoots. Only when infection of roots is promoted by jasmonates is wilt disease enhanced in a mutant deficient in salicylic acid biosynthesis. PMID:24387225

  17. Host perception of jasmonates promotes infection by Fusarium oxysporum formae speciales that produce isoleucine- and leucine-conjugated jasmonates.

    PubMed

    Cole, Stephanie J; Yoon, Alexander J; Faull, Kym F; Diener, Andrew C

    2014-08-01

    Three pathogenic forms, or formae speciales (f. spp.), of Fusarium oxysporum infect the roots of Arabidopsis thaliana below ground, instigating symptoms of wilt disease in leaves above ground. In previous reports, Arabidopsis mutants that are deficient in the biosynthesis of abscisic acid or salicylic acid or insensitive to ethylene or jasmonates exhibited either more or less wilt disease, than the wild-type, implicating the involvement of hormones in the normal host response to F. oxysporum. Our analysis of hormone-related mutants finds no evidence that endogenous hormones contribute to infection in roots. Mutants that are deficient in abscisic acid and insensitive to ethylene show no less infection than the wild-type, although they exhibit less disease. Whether a mutant that is insensitive to jasmonates affects infection depends on which forma specialis (f. sp.) is infecting the roots. Insensitivity to jasmonates suppresses infection by F. oxysporum f. sp. conglutinans and F. oxysporum f. sp. matthioli, which produce isoleucine- and leucine-conjugated jasmonate (JA-Ile/Leu), respectively, in culture filtrates, whereas insensitivity to jasmonates has no effect on infection by F. oxysporum f. sp. raphani, which produces no detectable JA-Ile/Leu. Furthermore, insensitivity to jasmonates has no effect on wilt disease of tomato, and the tomato pathogen F. oxysporum f. sp. lycopersici produces no detectable jasmonates. Thus, some, but not all, F. oxysporum pathogens appear to utilize jasmonates as effectors, promoting infection in roots and/or the development of symptoms in shoots. Only when the infection of roots is promoted by jasmonates is wilt disease enhanced in a mutant deficient in salicylic acid biosynthesis. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  18. Jasmonate action in plant growth and development.

    PubMed

    Huang, Huang; Liu, Bei; Liu, Liangyu; Song, Susheng

    2017-03-01

    Phytohormones, including jasmonates (JAs), gibberellin, ethylene, abscisic acid, and auxin, integrate endogenous developmental cues with environmental signals to regulate plant growth, development, and defense. JAs are well- recognized lipid-derived stress hormones that regulate plant adaptations to biotic stresses, including herbivore attack and pathogen infection, as well as abiotic stresses, including wounding, ozone, and ultraviolet radiation. An increasing number of studies have shown that JAs also have functions in a remarkable number of plant developmental events, including primary root growth, reproductive development, and leaf senescence. Since the 1980s, details of the JA biosynthesis pathway, signaling pathway, and crosstalk during plant growth and development have been elucidated. Here, we summarize recent advances and give an updated overview of JA action and crosstalk in plant growth and development. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Improved production of galanthamine and related alkaloids by methyl jasmonate in Narcissus confusus shoot-clumps.

    PubMed

    Colque, Raúl; Viladomat, Francesc; Bastida, Jaume; Codina, Carles

    2004-12-01

    Liquid-shake cultured shoot-clumps of Narcisus confussus were treated with the commonly used biotic elicitors methyl jasmonate, arachidonic acid, chitosan and salicylic acid. The effects of these compounds on the growth of the explants, as well as on the amount of the alkaloids released to the liquid culture medium and accumulated in the tissues at the end of the experiment were studied. The obtained results showed that, in general, high doses of these compounds had a negative effect on the growth of the explants, particularly the salicylic acid. On the contrary, the addition of methyl jasmonate, mainly at 25 microM, promoted the release of galanthamine and other related alkaloids to the liquid medium in proportions of up to 300% in relation to the control explants, and also their accumulation in tissues. The other elicitors studied did not have any interesting effects on the production of these Amaryllidaceae-type alkaloids.

  20. Integration of Ethylene and Jasmonic Acid Signaling Pathways in the Expression of Novel Maize Defense Protein Mir1-CP

    USDA-ARS?s Scientific Manuscript database

    In plants, ethylene (ET) and jasmonate (JA) control the defense responses to multiple stressors, including insect predation. Among the defense proteins known to be regulated by ET, is maize insect resistance 1-cysteine protease (Mir1-CP). This protein is constitutively expressed in the insect resi...

  1. Role of NINJA in root jasmonate signaling.

    PubMed

    Acosta, Iván F; Gasperini, Debora; Chételat, Aurore; Stolz, Stéphanie; Santuari, Luca; Farmer, Edward E

    2013-09-17

    Wound responses in plants have to be coordinated between organs so that locally reduced growth in a wounded tissue is balanced by appropriate growth elsewhere in the body. We used a JASMONATE ZIM DOMAIN 10 (JAZ10) reporter to screen for mutants affected in the organ-specific activation of jasmonate (JA) signaling in Arabidopsis thaliana seedlings. Wounding one cotyledon activated the reporter in both aerial and root tissues, and this was either disrupted or restricted to certain organs in mutant alleles of core components of the JA pathway including COI1, OPR3, and JAR1. In contrast, three other mutants showed constitutive activation of the reporter in the roots and hypocotyls of unwounded seedlings. All three lines harbored mutations in Novel Interactor of JAZ (NINJA), which encodes part of a repressor complex that negatively regulates JA signaling. These ninja mutants displayed shorter roots mimicking JA-mediated growth inhibition, and this was due to reduced cell elongation. Remarkably, this phenotype and the constitutive JAZ10 expression were still observed in backgrounds lacking the ability to synthesize JA or the key transcriptional activator MYC2. Therefore, JA-like responses can be recapitulated in specific tissues without changing a plant's ability to make or perceive JA, and MYC2 either has no role or is not the only derepressed transcription factor in ninja mutants. Our results show that the role of NINJA in the root is to repress JA signaling and allow normal cell elongation. Furthermore, the regulation of the JA pathway differs between roots and aerial tissues at all levels, from JA biosynthesis to transcriptional activation.

  2. Role of NINJA in root jasmonate signaling

    PubMed Central

    Acosta, Iván F.; Gasperini, Debora; Chételat, Aurore; Stolz, Stéphanie; Santuari, Luca; Farmer, Edward E.

    2013-01-01

    Wound responses in plants have to be coordinated between organs so that locally reduced growth in a wounded tissue is balanced by appropriate growth elsewhere in the body. We used a JASMONATE ZIM DOMAIN 10 (JAZ10) reporter to screen for mutants affected in the organ-specific activation of jasmonate (JA) signaling in Arabidopsis thaliana seedlings. Wounding one cotyledon activated the reporter in both aerial and root tissues, and this was either disrupted or restricted to certain organs in mutant alleles of core components of the JA pathway including COI1, OPR3, and JAR1. In contrast, three other mutants showed constitutive activation of the reporter in the roots and hypocotyls of unwounded seedlings. All three lines harbored mutations in Novel Interactor of JAZ (NINJA), which encodes part of a repressor complex that negatively regulates JA signaling. These ninja mutants displayed shorter roots mimicking JA-mediated growth inhibition, and this was due to reduced cell elongation. Remarkably, this phenotype and the constitutive JAZ10 expression were still observed in backgrounds lacking the ability to synthesize JA or the key transcriptional activator MYC2. Therefore, JA-like responses can be recapitulated in specific tissues without changing a plant’s ability to make or perceive JA, and MYC2 either has no role or is not the only derepressed transcription factor in ninja mutants. Our results show that the role of NINJA in the root is to repress JA signaling and allow normal cell elongation. Furthermore, the regulation of the JA pathway differs between roots and aerial tissues at all levels, from JA biosynthesis to transcriptional activation. PMID:24003128

  3. Application of a cognitive neuroscience perspective of cognitive control to late-life anxiety

    PubMed Central

    Beaudreau, Sherry A.; MacKay-Brandt, Anna; Reynolds, Jeremy

    2013-01-01

    Recent evidence supports a negative association between anxiety and cognitive control. Given age-related reductions in some cognitive abilities and the relation of late life anxiety to cognitive impairment, this negative association may be particularly relevant to older adults. This critical review conceptualizes anxiety and cognitive control from cognitive neuroscience and cognitive aging theoretical perspectives and evaluates the methodological approaches and measures used to assess cognitive control. Consistent with behavioral investigations of young adults, the studies reviewed implicate specific and potentially negative effects of anxiety on cognitive control processes in older adults. Hypotheses regarding the role of both aging and anxiety on cognitive control, the bi-directionality between anxiety and cognitive control, and the potential for specific symptoms of anxiety (particularly worry) to mediate this association, are specified and discussed. PMID:23602352

  4. Application of a cognitive neuroscience perspective of cognitive control to late-life anxiety.

    PubMed

    Beaudreau, Sherry A; MacKay-Brandt, Anna; Reynolds, Jeremy

    2013-08-01

    Recent evidence supports a negative association between anxiety and cognitive control. Given age-related reductions in some cognitive abilities and the relation of late life anxiety to cognitive impairment, this negative association may be particularly relevant to older adults. This critical review conceptualizes anxiety and cognitive control from cognitive neuroscience and cognitive aging theoretical perspectives and evaluates the methodological approaches and measures used to assess cognitive control. Consistent with behavioral investigations of young adults, the studies reviewed implicate specific and potentially negative effects of anxiety on cognitive control processes in older adults. Hypotheses regarding the role of both aging and anxiety on cognitive control, the bi-directionality between anxiety and cognitive control, and the potential for specific symptoms of anxiety (particularly worry) to mediate this association, are specified and discussed. Published by Elsevier Ltd.

  5. Unmatched Case-Control Study on Late Presentation of HIV Infection in Santiago, Cape Verde (2004–2011)

    PubMed Central

    Moreira, António L.; Fronteira, Inês; Augusto, Gonçalo Figueiredo; Martins, Maria Rosario O.

    2016-01-01

    Access to free antiretroviral therapy (ART) in Sub-Saharan Africa has been steadily increasing over the past decade. However, the success of large-scale ART programmes depends on timely diagnosis and early initiation of HIV care. This study characterizes late presenters to HIV care in Santiago (Cape Verde) between 2004 and 2011, and identifies factors associated with late presentation for care. We defined late presentation as persons presenting to HIV care with a CD4 count below 350 cells/mm3. An unmatched case-control study was conducted using socio-demographic and behavioural data of 368 individuals (191 cases and 177 controls) collected through an interviewer-administered questionnaire, comparing HIV patients late and early presented to care. Logistic regression was performed to estimate odds ratio and 95% confidence intervals. Results show that 51.9% were late presenters for HIV. No differences were found in gender distribution, marital status, or access to health services between cases and controls. Participants who undertook an HIV test by doctor indication were more likely to present late compared with those who tested for HIV by their own initiative. Also, individuals taking less time to initiate ART are more likely to present late. This study highlights the need to better understand reasons for late presentation to HIV care in Cape Verde. People in older age groups should be targeted in future approaches focused on late presenters to HIV care. PMID:26999167

  6. Unmatched Case-Control Study on Late Presentation of HIV Infection in Santiago, Cape Verde (2004-2011).

    PubMed

    Moreira, António L; Fronteira, Inês; Figueiredo Augusto, Gonçalo; Martins, Maria Rosario O

    2016-03-15

    Access to free antiretroviral therapy (ART) in Sub-Saharan Africa has been steadily increasing over the past decade. However, the success of large-scale ART programmes depends on timely diagnosis and early initiation of HIV care. This study characterizes late presenters to HIV care in Santiago (Cape Verde) between 2004 and 2011, and identifies factors associated with late presentation for care. We defined late presentation as persons presenting to HIV care with a CD4 count below 350 cells/mm³. An unmatched case-control study was conducted using socio-demographic and behavioural data of 368 individuals (191 cases and 177 controls) collected through an interviewer-administered questionnaire, comparing HIV patients late and early presented to care. Logistic regression was performed to estimate odds ratio and 95% confidence intervals. Results show that 51.9% were late presenters for HIV. No differences were found in gender distribution, marital status, or access to health services between cases and controls. Participants who undertook an HIV test by doctor indication were more likely to present late compared with those who tested for HIV by their own initiative. Also, individuals taking less time to initiate ART are more likely to present late. This study highlights the need to better understand reasons for late presentation to HIV care in Cape Verde. People in older age groups should be targeted in future approaches focused on late presenters to HIV care.

  7. Suppression of Fe deficiency gene expression by jasmonate.

    PubMed

    Maurer, Felix; Müller, Sabine; Bauer, Petra

    2011-05-01

    Fe deficiency genes are regulated in response to external supply of Fe as well as internal plant signals. Internal plant signals include plant hormones and systemic signals which coordinate shoot physiological requirements for Fe with local availability of Fe in roots. Induction of IRT1 and FRO2 gene expression can be used to monitor the Fe deficiency status of plant roots. Here, we investigated the role of jasmonate in the regulation of Fe deficiency responses and in the split root system. We found that jasmonate suppressed expression levels of IRT1 and FRO2 but not their inducibility in response to Fe deficiency. Analysis of the jasmonate-resistant mutant jar1-1 and pharmacological application of the lipoxygenase inhibitor ibuprofene supported an inhibitory effect of this plant hormone. Inhibition of IRT1 and FRO2 gene expression by jasmonate did not require the functional regulator FIT. By performing split root analyses we found that systemic down-regulation of Fe deficiency responses by Fe sufficiency of the shoot was not compromised by ibuprofene and in the jasmonate-insensitive mutant coi1-1. Therefore, we conclude that jasmonate acts as an inhibitor in fine-tuning Fe deficiency responses but that it is not involved in the systemic down-regulation of Fe deficiency responses in the root.

  8. Late Paleozoic anorogenic magmatism in Southern Mongolia: Evolutionary stages and structural control

    NASA Astrophysics Data System (ADS)

    Yarmolyuk, V. V.; Kozlovsky, A. M.; Travin, A. V.

    2017-07-01

    Geochronological studies of anorogenic magmatic complexes in the South Mongolian Hercinide have been carried out. Series of the massifs composed of alkaline and subalkaline granitoids with some monzonite formed during the interval of 318-316 Ma have been found. Taking into account previously obtained data, two groups of Late Paleozoic A-type granitoids different in age have been identified in the region: Late Carboniferous and Early Permian. These two occupy different structural positions. The location the early magmatic massifs is controlled by the extended Trans-Altai fault zone of northwest strike: the massifs cluster in areas of the fault intersection with boundaries of structural blocks formed by the pull-apart mechanism. The later Early Permian igneous complexes are associated with the Gobi-Tienshan rift zone of sublatitudinal strike.

  9. Effects of methyl jasmonate on accumulation of flavonoids in seedlings of common buckwheat (Fagopyrum esculentum Moench).

    PubMed

    Horbowicz, M; Wiczkowski, W; Koczkodaj, Danuta; Saniewski, M

    2011-09-01

    The jasmonates, which include jasmonic acid and its methyl ester (MJ), play a central role in regulating the biosynthesis of many secondary metabolites, including flavonoids, and also are signaling molecules in environmental stresses. Synthesis of anthocyanins pigments is a final part of flavonoids pathway route. Accumulation of the pigments in young seedlings is stimulated by various environmental stresses, such as high-intensity light, wounding, pathogen attack, drought, sugar and nutrient deficiency. The anthocyanins take part in defense system against excess of light and UV-B light, and therefore it is probably main reason why young plant tissues accumulate enlarged levels of the pigments. The effects of exogenously applied MJ on level of anthocyanins, glycosides of apigenin, luteolin, quercetin and proanthocyanidins in seedlings of common buckwheat (Fagopyrum esculentum Moench) were studied. MJ decreased contents of all the found cyanidin glycosides and its aglycone in hypocotyls of buckwheat seedlings. However contents of particular anthocyanins in cotyledons of buckwheat seedlings treated with the plant hormone were not significantly different from the control. Applied doses of MJ did not affect levels of quercetin, apigenin and luteolin glycosides in the analyzed parts of buckwheat seedlings: cotyledons and hypocotyls. On the other hand, treatment of buckwheat seedlings with MJ clearly stimulated of proanthocyanidins biosynthesis in hypocotyls. We suggest that methyl jasmonate induces in hypocotyls of buckwheat seedlings the leucocyanidin reductase or anthocyanidin reductase, possible enzymes in proanthocyanidins synthesis, and/or inhibits anthocyanidin synthase, which transforms leucocyanidin into cyanidin. According to our knowledge this is the first report regarding the effect of methyl jasmonate on enhancing the accumulation of proanthocyanidins in cultivated plants.

  10. Jasmonic acid induced protein response to biophoton emissions and flooding stress in soybean.

    PubMed

    Kamal, Abu Hena Mostafa; Komatsu, Setsuko

    2016-02-05

    Biophoton emissions were elevated by the exogenous plant hormone application such as jasmonic (JA) and salicylic acid (SA). To reveal the molecular mechanisms underlying flooding stress responses in soybean treated with JA and SA, biophoton emissions from plants were quantified in combination with proteomic analyses. Furthermore, treatment with exogenous JA inhibited lateral root growth and markedly reduced root weight. Out of 649 proteins identified in the JA- and JA/SA-treated plants, 44 were unique to JA-treated plants, 403 were unique to JA/SA-treated plants, and 202 were shared between the groups. These proteins were involved in stress, signaling, degradation, glycolysis, fermentation, and hormone metabolism. The abundances of glutathione-S-transferase, alanine aminotransferase, and malate dehydrogenase were decreased; however, the activities of these enzymes were increased. In contrast, the abundance and activity of monodehydroascorbate reductase increased in the roots of plants treated with JA and SA under flooding stress. This suggests that the quantity of lateral roots, total root mass, and free radicals generated during oxidation and reduction reactions and reactive oxygen species scavenging largely contribute to biophoton emission. Furthermore, monodehydroascorbate reductase, which is involved in detoxification and controlling hydrogen peroxide levels, may protect plant cells against oxidative damage during flooding. To understand the source of biophoton emission and molecular mechanism by the application of jasmonic and salicylic acid under flooding conditions in soybean plants, the label-free quantitative techniques were performed in roots. Root lengths and weights were significantly reduced by the effect of jasmonic and salicylic acid while it inhibited growth of the lateral roots in normal conditions using the jasmonic acid. Finally, identified proteins were functionally annotated by MAPMAN software application; that were assigned to different

  11. The JAZ Proteins: A Crucial Interface in the Jasmonate Signaling Cascade

    PubMed Central

    Pauwels, Laurens; Goossens, Alain

    2011-01-01

    Jasmonates are phytohormones that regulate many aspects of plant growth, development, and defense. Within the signaling cascades that are triggered by jasmonates, the JASMONATE-ZIM DOMAIN (JAZ) repressor proteins play a central role. The endogenous bioactive JA-Ile conjugate mediates the binding of JAZ proteins to the F-box protein CORONATINE INSENSITIVE1 (COI1), part of the Skp1/Cullin/F-box SCFCOI1 ubiquitin E3 ligase complex. Upon the subsequent destruction of the JAZ proteins by the 26S proteasome, multiple transcription factors are relieved from JAZ-mediated repression, allowing them to activate their respective downstream responses. However, many questions remain regarding the targets, specificity, function, and regulation of the different JAZ proteins. Here, we review recent studies on the model plant Arabidopsis thaliana that provided essential and novel insights. JAZ proteins have been demonstrated to interact with a broad array of transcription factors that each control specific downstream processes. Recruitment of the corepressor TOPLESS unveiled a mechanism for JAZ-mediated gene repression. Finally, the presence of JAZ proteins was also found to be regulated by alternative splicing and interactions with proteins from other hormonal signaling pathways. Overall, these contemporary findings underscore the value of protein–protein interaction studies to acquire fundamental insight into molecular signaling pathways. PMID:21963667

  12. Genetic architecture of plastic methyl jasmonate responses in Arabidopsis thaliana.

    PubMed Central

    Kliebenstein, Daniel J; Figuth, Antje; Mitchell-Olds, Thomas

    2002-01-01

    The ability of a single genotype to generate different phenotypes in disparate environments is termed phenotypic plasticity, which reflects the interaction of genotype and environment on developmental processes. However, there is controversy over the definition of plasticity genes. The gene regulation model states that plasticity loci influence trait changes between environments without altering the means within a given environment. Alternatively, the allelic sensitivity model argues that plasticity evolves due to selection of phenotypic values expressed within particular environments; hence plasticity must be controlled by loci expressed within these environments. To identify genetic loci controlling phenotypic plasticity and address this controversy, we analyzed the plasticity of glucosinolate accumulation under methyl jasmonate (MeJa) treatment in Arabidopsis thaliana. We found genetic variation influencing multiple MeJa signal transduction pathways. Analysis of MeJa responses in the Landsberg erecta x Columbia recombinant inbred lines identified a number of quantitative trait loci (QTL) that regulate plastic MeJa responses. All significant plasticity QTL also impacted the mean trait value in at least one of the two "control" or "MeJa" environments, supporting the allelic sensitivity model. Additionally, we present an analysis of MeJa and salicylic acid cross-talk in glucosinolate regulation and describe the implications for glucosinolate physiology and functional understanding of Arabidopsis MeJa signal transduction. PMID:12196411

  13. Deficient prefrontal attentional control in late-life generalized anxiety disorder: an fMRI investigation.

    PubMed

    Price, R B; Eldreth, D A; Mohlman, J

    2011-10-04

    Younger adults with anxiety disorders are known to show an attentional bias toward negative information. Little is known regarding the role of biased attention in anxious older adults, and even less is known about the neural substrates of any such bias. Functional magnetic resonance imaging (fMRI) was used to assess the mechanisms of attentional bias in late life by contrasting predictions of a top-down model emphasizing deficient prefrontal cortex (PFC) control and a bottom-up model emphasizing amygdalar hyperreactivity. In all, 16 older generalized anxiety disorder (GAD) patients (mean age=66 years) and 12 non-anxious controls (NACs; mean age=67 years) completed the emotional Stroop task to assess selective attention to negative words. Task-related fMRI data were concurrently acquired. Consistent with hypotheses, GAD participants were slower to identify the color of negative words relative to neutral, whereas NACs showed the opposite bias, responding more quickly to negative words. During negative words (in comparison with neutral), the NAC group showed PFC activations, coupled with deactivation of task-irrelevant emotional processing regions such as the amygdala and hippocampus. By contrast, GAD participants showed PFC decreases during negative words and no differences in amygdalar activity across word types. Across all participants, greater attentional bias toward negative words was correlated with decreased PFC recruitment. A significant positive correlation between attentional bias and amygdala activation was also present, but this relationship was mediated by PFC activity. These results are consistent with reduced prefrontal attentional control in late-life GAD. Strategies to enhance top-down attentional control may be particularly relevant in late-life GAD treatment.

  14. Trajectories of late-life change in God-mediated control.

    PubMed

    Hayward, R David; Krause, Neal

    2013-01-01

    To track within-individual change during late life in the sense of personal control and God-mediated control (the belief that one can work collaboratively with God to achieve one's goals and exercise control over life events) and to evaluate the hypothesis that this element of religion is related to declining personal control. A longitudinal survey representative of older White and Black adults in the United States tracked changes in personal and God-mediated control in four waves over the course of 7 years. Growth curve analysis found that the pattern of change differed by race. White adults had less sense of God-mediated control at younger ages, which increased among those who were highly religious but decreased among those who were less religious. Black adults had higher God-mediated control, which increased over time among those with low personal control. These results indicate that God-mediated control generally increases during older adulthood, but that its relationships with personal control and religious commitment are complex and differ between Black and White adults.

  15. Trajectories of Late-Life Change in God-Mediated Control

    PubMed Central

    2013-01-01

    Objective. To track within-individual change during late life in the sense of personal control and God-mediated control (the belief that one can work collaboratively with God to achieve one’s goals and exercise control over life events) and to evaluate the hypothesis that this element of religion is related to declining personal control. Method A longitudinal survey representative of older White and Black adults in the United States tracked changes in personal and God-mediated control in four waves over the course of 7 years. Results. Growth curve analysis found that the pattern of change differed by race. White adults had less sense of God-mediated control at younger ages, which increased among those who were highly religious but decreased among those who were less religious. Black adults had higher God-mediated control, which increased over time among those with low personal control. Discussion These results indicate that God-mediated control generally increases during older adulthood, but that its relationships with personal control and religious commitment are complex and differ between Black and White adults. PMID:22865820

  16. Late Pliocene Greenland glaciation controlled by a decline in atmospheric CO2 levels.

    PubMed

    Lunt, Daniel J; Foster, Gavin L; Haywood, Alan M; Stone, Emma J

    2008-08-28

    It is thought that the Northern Hemisphere experienced only ephemeral glaciations from the Late Eocene to the Early Pliocene epochs (about 38 to 4 million years ago), and that the onset of extensive glaciations did not occur until about 3 million years ago. Several hypotheses have been proposed to explain this increase in Northern Hemisphere glaciation during the Late Pliocene. Here we use a fully coupled atmosphere-ocean general circulation model and an ice-sheet model to assess the impact of the proposed driving mechanisms for glaciation and the influence of orbital variations on the development of the Greenland ice sheet in particular. We find that Greenland glaciation is mainly controlled by a decrease in atmospheric carbon dioxide during the Late Pliocene. By contrast, our model results suggest that climatic shifts associated with the tectonically driven closure of the Panama seaway, with the termination of a permanent El Niño state or with tectonic uplift are not large enough to contribute significantly to the growth of the Greenland ice sheet; moreover, we find that none of these processes acted as a priming mechanism for glacial inception triggered by variations in the Earth's orbit.

  17. What controls early or late onset of tropical North Atlantic hurricane season?

    NASA Astrophysics Data System (ADS)

    Zuo, Heng; Li, Tim; Liu, Jia; Peng, Melinda

    2016-06-01

    The occurrence of first hurricane in early summer signifies the onset of an active Atlantic hurricane season. The interannual variation of this hurricane onset date is examined for the period 1979-2013. It is found that the onset date has a marked interannual variation. The standard deviation of the interannual variation of the onset day is 17.5 days, with the climatological mean onset happening on July 23. A diagnosis of tropical cyclone (TC) genesis potential index (GPI) indicates that the major difference between an early and a late onset group lies in the maximum potential intensity (MPI). A further diagnosis of the MPI shows that it is primarily controlled by the local SST anomaly (SSTA). Besides the SSTA, vertical shear and mid-tropospheric relative humidity anomalies also contribute significantly to the GPI difference between the early and late onset groups. It is found that the anomalous warm (cold) SST over the tropical Atlantic, while uncorrelated with the Niño3 index, persists from the preceding winter to concurrent summer in the early (late) onset group. The net surface heat flux anomaly always tends to damp the SSTA, which suggests that ocean dynamics may play a role in maintaining the SSTA in the tropical Atlantic. The SSTA pattern with a maximum center in northeastern tropical Atlantic appears responsible for generating the observed wind and moisture anomalies over the main TC development region. A further study is needed to understand the initiation mechanism of the SSTA in the Atlantic.

  18. Parthenolide accumulation and expression of genes related to parthenolide biosynthesis affected by exogenous application of methyl jasmonate and salicylic acid in Tanacetum parthenium.

    PubMed

    Majdi, Mohammad; Abdollahi, Mohammad Reza; Maroufi, Asad

    2015-11-01

    Up-regulation of germacrene A synthase and down-regulation of parthenolide hydroxylase genes play key role in parthenolide accumulation of feverfew plants treated with methyl jasmonate and salicylic acid. Parthenolide is an important sesquiterpene lactone due to its anti-migraine and anti-cancer properties. Parthenolide amount was quantified by high-performance liquid chromatography after foliar application of methyl jasmonate (100 µM) or salicylic acid (1.0 mM) on feverfew leaves in time course experiment (3-96 h). Results indicate that exogenous application of methyl jasmonate or salicylic acid activated parthenolide biosynthesis. Parthenolide content reached its highest amount at 24 h after methyl jasmonate or salicylic acid treatments, which were 3.1- and 1.96-fold higher than control plants, respectively. Parthenolide transiently increased due to methyl jasmonate or salicylic acid treatments until 24 h, but did not show significant difference compared with control plants at 48 and 96 h time points in both treatments. Also, the transcript levels of early pathway (upstream) genes of terpene biosynthesis including 3-hydroxy-3-methylglutaryl-coenzyme A reductase, 1-deoxy-D-xylulose-5-phosphate reductoisomerase and hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase and the biosynthetic genes of parthenolide including germacrene A synthase, germacrene A oxidase, costunolide synthase and parthenolide synthase were increased by methyl jasmonate and salicylic acid treatments, but with different intensity. The transcriptional levels of these genes were higher in methyl jasmonate-treated plants than salicylic acid-treated plants. Parthenolide content measurements along with expression pattern analysis of the aforementioned genes and parthenolide hydroxylase as side branch gene of parthenolide suggest that the expression patterns of early pathway genes were not directly consistent with parthenolide accumulation pattern; hence, parthenolide accumulation is

  19. Orbital control on the timing of oceanic anoxia in the Late Cretaceous

    NASA Astrophysics Data System (ADS)

    Batenburg, Sietske J.; De Vleeschouwer, David; Sprovieri, Mario; Hilgen, Frederik J.; Gale, Andrew S.; Singer, Brad S.; Koeberl, Christian; Coccioni, Rodolfo; Claeys, Philippe; Montanari, Alessandro

    2016-10-01

    The oceans at the time of the Cenomanian-Turonian transition were abruptly perturbed by a period of bottom-water anoxia. This led to the brief but widespread deposition of black organic-rich shales, such as the Livello Bonarelli in the Umbria-Marche Basin (Italy). Despite intensive studies, the origin and exact timing of this event are still debated. In this study, we assess leading hypotheses about the inception of oceanic anoxia in the Late Cretaceous greenhouse world by providing a 6 Myr long astronomically tuned timescale across the Cenomanian-Turonian boundary. We procure insights into the relationship between orbital forcing and the Late Cretaceous carbon cycle by deciphering the imprint of astronomical cycles on lithologic, physical properties, and stable isotope records, obtained from the Bottaccione, Contessa and Furlo sections in the Umbria-Marche Basin. The deposition of black shales and cherts, as well as the onset of oceanic anoxia, is related to maxima in the 405 kyr cycle of eccentricity-modulated precession. Correlation to radioisotopic ages from the Western Interior (USA) provides unprecedented age control for the studied Italian successions. The most likely tuned age for the base of the Livello Bonarelli is 94.17 ± 0.15 Ma (tuning 1); however, a 405 kyr older age cannot be excluded (tuning 2) due to uncertainties in stratigraphic correlation, radioisotopic dating, and orbital configuration. Our cyclostratigraphic framework suggests that the exact timing of major carbon cycle perturbations during the Cretaceous may be linked to increased variability in seasonality (i.e. a 405 kyr eccentricity maximum) after the prolonged avoidance of seasonal extremes (i.e. a 2.4 Myr eccentricity minimum). Volcanism is probably the ultimate driver of oceanic anoxia, but orbital periodicities determine the exact timing of carbon cycle perturbations in the Late Cretaceous. This unites two leading hypotheses about the inception of oceanic anoxia in the Late

  20. Long-Term Improvements After Multimodal Rehabilitation in Late Phase After Stroke: A Randomized Controlled Trial.

    PubMed

    Bunketorp-Käll, Lina; Lundgren-Nilsson, Åsa; Samuelsson, Hans; Pekny, Tulen; Blomvé, Karin; Pekna, Marcela; Pekny, Milos; Blomstrand, Christian; Nilsson, Michael

    2017-07-01

    Treatments that improve function in late phase after stroke are urgently needed. We assessed whether multimodal interventions based on rhythm-and-music therapy or horse-riding therapy could lead to increased perceived recovery and functional improvement in a mixed population of individuals in late phase after stroke. Participants were assigned to rhythm-and-music therapy, horse-riding therapy, or control using concealed randomization, stratified with respect to sex and stroke laterality. Therapy was given twice a week for 12 weeks. The primary outcome was change in participants' perception of stroke recovery as assessed by the Stroke Impact Scale with an intention-to-treat analysis. Secondary objective outcome measures were changes in balance, gait, grip strength, and cognition. Blinded assessments were performed at baseline, postintervention, and at 3- and 6-month follow-up. One hundred twenty-three participants were assigned to rhythm-and-music therapy (n=41), horse-riding therapy (n=41), or control (n=41). Post-intervention, the perception of stroke recovery (mean change from baseline on a scale ranging from 1 to 100) was higher among rhythm-and-music therapy (5.2 [95% confidence interval, 0.79-9.61]) and horse-riding therapy participants (9.8 [95% confidence interval, 6.00-13.66]), compared with controls (-0.5 [-3.20 to 2.28]); P=0.001 (1-way ANOVA). The improvements were sustained in both intervention groups 6 months later, and corresponding gains were observed for the secondary outcomes. Multimodal interventions can improve long-term perception of recovery, as well as balance, gait, grip strength, and working memory in a mixed population of individuals in late phase after stroke. URL: http//www.ClinicalTrials.gov. Unique identifier: NCT01372059. © 2017 American Heart Association, Inc.

  1. IMRT for Sinonasal Tumors Minimizes Severe Late Ocular Toxicity and Preserves Disease Control and Survival

    SciTech Connect

    Duprez, Frederic; Madani, Indira; Morbee, Lieve; Bonte, Katrien; Deron, Philippe; Domjan, Vilmos; Boterberg, Tom; De Gersem, Werner; De Neve, Wilfried

    2012-05-01

    Purpose: To report late ocular (primary endpoint) and other toxicity, disease control, and survival (secondary endpoints) after intensity-modulated radiotherapy (IMRT) for sinonasal tumors. Methods and Materials: Between 1998 and 2009, 130 patients with nonmetastatic sinonasal tumors were treated with IMRT at Ghent University Hospital. Prescription doses were 70 Gy (n = 117) and 60-66 Gy (n = 13) at 2 Gy per fraction over 6-7 weeks. Most patients had adenocarcinoma (n = 82) and squamous cell carcinoma (n = 23). One hundred and one (101) patients were treated postoperatively. Of 17 patients with recurrent tumors, 9 were reirradiated. T-stages were T1-2 (n = 39), T3 (n = 21), T4a (n = 38), and T4b (n = 22). Esthesioneuroblastoma was staged as Kadish A, B, and C in 1, 3, and 6 cases, respectively. Results: Median follow-up was 52, range 15-121 months. There was no radiation-induced blindness in 86 patients available for late toxicity assessment ({>=}6 month follow-up). We observed late Grade 3 tearing in 10 patients, which reduced to Grade 1-2 in 5 patients and Grade 3 visual impairment because of radiation-induced ipsilateral retinopathy and neovascular glaucoma in 1 patient. There was no severe dry eye syndrome. The worst grade of late ocular toxicity was Grade 3 (n = 11), Grade 2 (n = 31), Grade 1 (n = 33), and Grade 0 (n = 11). Brain necrosis and osteoradionecrosis occurred in 6 and 1 patients, respectively. Actuarial 5-year local control and overall survival were 59% and 52%, respectively. On multivariate analysis local control was negatively affected by cribriform plate and brain invasion (p = 0.044 and 0.029, respectively) and absence of surgery (p = 0.009); overall survival was negatively affected by cribriform plate and orbit invasion (p = 0.04 and <0.001, respectively) and absence of surgery (p = 0.001). Conclusions: IMRT for sinonasal tumors allowed delivering high doses to targets at minimized ocular toxicity, while maintaining disease control and survival

  2. Temperamental Effortful Control Modulates Gender Differences in Late Positive Potentials Evoked by Affective Pictures in Adolescents.

    PubMed

    Zhang, Wenhai; Suo, Tao; Zhang, Ping; Zhao, Cancan; Liao, Caizhi; Zhang, Liwei; Li, Hong

    2017-01-01

    We investigated whether effort control (EC) modulates gender differences in late positive potential (LPP) evoked by affective pictures. We collected EEG data from 46 healthy adolescents while they viewed 90 affective pictures. Relative to neutral pictures, boys showed larger LPP amplitudes for positive pictures compared to girls while girls showed larger LPP amplitudes for negative pictures compared to boys. Temperamental EC in boys negatively predicted LPP amplitudes for positive pictures, whereas EC in girls negatively predicted LPP amplitudes for negative pictures. These observations increase our understanding of the relationship between EC and gender difference in electrocortical maturation.

  3. Effect of methyl jasmonate, sodium selenate and chitosan as exogenous elicitors on the phenolic compounds profile of broccoli sprouts.

    PubMed

    Carvacho, Herna Barrientos; Pérez, Carmen; Zúñiga, Gustavo; Mahn, Andrea

    2014-09-01

    Broccoli sprouts are a good source of secondary metabolites, exhibiting biological activity, such as polyphenols, whose concentration is affected by the exposure to exogenous elicitors. The aim of this work was to investigate the effect of sodium selenate, chitosan and methyl jasmonate, applied directly to the seeds or through irrigation, on the content and profile of phenolic compounds in broccoli sprouts. The effect on antioxidant activity was also investigated. Methyl jasmonate and chitosan decreased antioxidant capacity. Methyl jasmonate significantly decreased total polyphenols content in comparison with control sprouts, while chitosan significantly increased it. Sodium selenate had no statistical effect on antioxidant capacity and total polyphenols concentration. The polyphenols profile in sprouts was composed by quercetin, morine, genisteine, luteoline and sinapic acid. Elicitor type and concentration affected the synthesis of these compounds. Chitosan stimulated the synthesis of quercetin, sinapic acid and morine, whereas methyl jasmonate stimulated the synthesis of luteoline. Sodium selenate had no effect on polyphenols synthesis. The exposure of broccoli to the elicitors produced changes in the phenolic compounds profile of broccoli sprouts. Besides, the stimulation of phenolic compounds synthesis was elicitor-specific, thus opening the possibility of managing culture conditions to increase the content of a specific phenolic compound. © 2014 Society of Chemical Industry.

  4. Synthesis and Functions of Jasmonates in Maize

    PubMed Central

    Borrego, Eli J.; Kolomiets, Michael V.

    2016-01-01

    Of the over 600 oxylipins present in all plants, the phytohormone jasmonic acid (JA) remains the best understood in terms of its biosynthesis, function and signaling. Much like their eicosanoid analogues in mammalian system, evidence is growing for the role of the other oxylipins in diverse physiological processes. JA serves as the model plant oxylipin species and regulates defense and development. For several decades, the biology of JA has been characterized in a few dicot species, yet the function of JA in monocots has only recently begun to be elucidated. In this work, the synthesis and function of JA in maize is presented from the perspective of oxylipin biology. The maize genes responsible for catalyzing the reactions in the JA biosynthesis are clarified and described. Recent studies into the function of JA in maize defense against insect herbivory, pathogens and its role in growth and development are highlighted. Additionally, a list of JA-responsive genes is presented for use as biological markers for improving future investigations into JA signaling in maize. PMID:27916835

  5. Methyl Jasmonate Reduces Water Stress in Strawberry.

    PubMed

    Wang

    1999-11-01

    The effect of methyl jasmonate (MJ) on changes of oxygen-scavenging enzyme activities and membrane lipid composition was studied in strawberry leaves under water stress. Under water stress, MJ treatment reduced the increase of peroxidase (EC 1.11.1.7; POD) activity, maintained higher catalase (EC 1.11.1.6; CAT) and superoxide dismutase (EC 1.15.1.1; SOD) activities, and ascorbic acid content. In addition, MJ treatment reduced transpiration and membrane-lipid peroxidation as expressed by malondialdehyde (MDA) content, lessened the reduction of membrane lipids, glycolipids [monogalactosyl diglyceride (MGDG), digalactosyl diglyceride (DGDG)], and phospholipids [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and phosphatidylinositol (PI)]. In water-deficit conditions, MJ treatment also alleviated the decline in the degree of fatty acid unsaturation and the ratio of linolenic (18:3) to linoleic acid (18:2). These results indicate that MJ treatment appears to alter the metabolism of strawberry plants rendering the tissue better able to withstand water stress.

  6. Why are they late? Timing abilities and executive control among students with learning disabilities.

    PubMed

    Grinblat, Nufar; Rosenblum, Sara

    2016-12-01

    While a deficient ability to perform daily tasks on time has been reported among students with learning disabilities (LD), the underlying mechanism behind their 'being late' is still unclear. This study aimed to evaluate the organization in time, time estimation abilities, actual performance time pertaining to specific daily activities, as well as the executive functions of students with LD in comparison to those of controls, and to assess the relationships between these domains among each group. The participants were 27 students with LD, aged 20-30, and 32 gender and age-matched controls who completed the Time Organization and Participation Scale (TOPS) and the Behavioral Rating Inventory of Executive Function-Adult version (BRIEF-A). In addition, their ability to estimate the time needed to complete the task of preparing a cup of coffee as well as their actual performance time were evaluated. The results indicated that in comparison to controls, students with LD showed significantly inferior organization in time (TOPS) and executive function abilities (BRIEF-A). Furthermore, their time estimation abilities were significantly inferior and they required significantly more time to prepare a cup of coffee. Regression analysis identified the variables that predicted organization in time and task performance time among each group. The significance of the results for both theoretical and clinical implications are discussed. What this paper adds? This study examines the underlying mechanism of the phenomena of being late among students with LD. Following a recent call for using ecologically valid assessments, the functional daily ability of students with LD to prepare a cup of coffee and to organize time were investigated. Furthermore, their time estimation and executive control abilities were examined as a possible underlying mechanism for their lateness. Although previous studies have indicated executive control deficits among students with LD, to our knowledge, this

  7. Jasmonates: An Update on Biosynthesis, Signal Transduction and Action in Plant Stress Response, Growth and Development

    PubMed Central

    Wasternack, C.

    2007-01-01

    Background Jasmonates are ubiquitously occurring lipid-derived compounds with signal functions in plant responses to abiotic and biotic stresses, as well as in plant growth and development. Jasmonic acid and its various metabolites are members of the oxylipin family. Many of them alter gene expression positively or negatively in a regulatory network with synergistic and antagonistic effects in relation to other plant hormones such as salicylate, auxin, ethylene and abscisic acid. Scope This review summarizes biosynthesis and signal transduction of jasmonates with emphasis on new findings in relation to enzymes, their crystal structure, new compounds detected in the oxylipin and jasmonate families, and newly found functions. Conclusions Crystal structure of enzymes in jasmonate biosynthesis, increasing number of jasmonate metabolites and newly identified components of the jasmonate signal-transduction pathway, including specifically acting transcription factors, have led to new insights into jasmonate action, but its receptor(s) is/are still missing, in contrast to all other plant hormones. PMID:17513307

  8. Jasmonates: an update on biosynthesis, signal transduction and action in plant stress response, growth and development.

    PubMed

    Wasternack, C

    2007-10-01

    Jasmonates are ubiquitously occurring lipid-derived compounds with signal functions in plant responses to abiotic and biotic stresses, as well as in plant growth and development. Jasmonic acid and its various metabolites are members of the oxylipin family. Many of them alter gene expression positively or negatively in a regulatory network with synergistic and antagonistic effects in relation to other plant hormones such as salicylate, auxin, ethylene and abscisic acid. This review summarizes biosynthesis and signal transduction of jasmonates with emphasis on new findings in relation to enzymes, their crystal structure, new compounds detected in the oxylipin and jasmonate families, and newly found functions. Crystal structure of enzymes in jasmonate biosynthesis, increasing number of jasmonate metabolites and newly identified components of the jasmonate signal-transduction pathway, including specifically acting transcription factors, have led to new insights into jasmonate action, but its receptor(s) is/are still missing, in contrast to all other plant hormones.

  9. Methyl jasmonate binds to and detaches mitochondria-bound hexokinase.

    PubMed

    Goldin, N; Arzoine, L; Heyfets, A; Israelson, A; Zaslavsky, Z; Bravman, T; Bronner, V; Notcovich, A; Shoshan-Barmatz, V; Flescher, E

    2008-08-07

    Cellular bio-energetic metabolism and mitochondria are recognized as potential targets for anticancer agents, due to the numerous relevant peculiarities cancer cells exhibit. Jasmonates are anticancer agents that interact directly with mitochondria. The aim of this study was to identify mitochondrial molecular targets of jasmonates. We report that jasmonates bind to hexokinase and detach it from the mitochondria and its mitochondrial anchor-the voltage-dependent anion channel (VDAC), as judged by hexokinase immunochemical and activity determinations, surface plasmon resonance analysis and planar lipid bilayer VDAC-activity analysis. Furthermore, the susceptibility of cancer cells and mitochondria to jasmonates is dependent on the expression of hexokinase, evaluated using hexokinase-overexpressing transfectants and its mitochondrial association. Many types of cancer cells exhibit overexpression of the key glycolytic enzyme, hexokinase, and its excessive binding to mitochondria. These characteristics are considered to play a pivotal role in cancer cell growth rate and survival. Thus, our findings provide an explanation for the selective effects of jasmonates on cancer cells. Most importantly, this is the first demonstration of a cytotoxic mechanism based on direct interaction between an anticancer agent and hexokinase. The proposed mechanism can serve to guide development of a new selective approach for cancer therapy.

  10. Functional Analysis of Jasmonates in Rice through Mutant Approaches

    PubMed Central

    Dhakarey, Rohit; Kodackattumannil Peethambaran, Preshobha; Riemann, Michael

    2016-01-01

    Jasmonic acid, one of the major plant hormones, is, unlike other hormones, a lipid-derived compound that is synthesized from the fatty acid linolenic acid. It has been studied intensively in many plant species including Arabidopsis thaliana, in which most of the enzymes participating in its biosynthesis were characterized. In the past 15 years, mutants and transgenic plants affected in the jasmonate pathway became available in rice and facilitate studies on the functions of this hormone in an important crop. Those functions are partially conserved compared to other plant species, and include roles in fertility, response to mechanical wounding and defense against herbivores. However, new and surprising functions have also been uncovered by mutant approaches, such as a close link between light perception and the jasmonate pathway. This was not only useful to show a phenomenon that is unique to rice but also helped to establish this role in plant species where such links are less obvious. This review aims to provide an overview of currently available rice mutants and transgenic plants in the jasmonate pathway and highlights some selected roles of jasmonate in this species, such as photomorphogenesis, and abiotic and biotic stress. PMID:27135235

  11. Exploring the impact of wounding and jasmonates on ascorbate metabolism

    PubMed Central

    Suza, Walter P.; Avila, Carlos A.; Carruthers, Kelly; Kulkarni, Shashank; Goggin, Fiona L.; Lorence, Argelia

    2010-01-01

    Vitamin C (ascorbate, AsA) is the most abundant water-soluble antioxidant in plants. Ascorbate provides the first line of defense against damaging reactive oxygen species (ROS), and helps protect plant cells from many factors that induce oxidative stress, including wounding, ozone, high salinity, and pathogen attack. Plant defenses against these stresses are also dependent upon jasmonates (JAs), a class of plant hormones that promote ROS accumulation. Here, we review evidence showing that wounding and JAs influence AsA accumulation in various plant species, and we report new data from Arabidopsis and tomato testing the influence of JAs on AsA levels in wounded and unwounded plants. In both species, certain mutations that impair JA metabolism and signaling influence foliar AsA levels, suggesting that endogenous JAs may regulate steady-state AsA. However, the impact of wounding on AsA accumulation was similar in JA mutants and wild type controls, indicating that this wound response does not require JAs. Our findings also indicate that the effects of wounding and JAs on AsA accumulation differ between species; these factors both enhanced AsA accumulation in Arabidopsis, but depressed AsA levels in tomato. These results underscore the importance of obtaining data from more than one model species, and demonstrate the complexity of AsA regulation. PMID:20346686

  12. Comparative transcript profiling by SuperSAGE identifies novel candidate genes for controlling potato quantitative resistance to late blight not compromised by late maturity

    PubMed Central

    Draffehn, Astrid M.; Li, Li; Krezdorn, Nicolas; Ding, Jia; Lübeck, Jens; Strahwald, Josef; Muktar, Meki S.; Walkemeier, Birgit; Rotter, Björn; Gebhardt, Christiane

    2013-01-01

    Resistance to pathogens is essential for survival of wild and cultivated plants. Pathogen susceptibility causes major losses of crop yield and quality. Durable field resistance combined with high yield and other superior agronomic characters are therefore, important objectives in every crop breeding program. Precision and efficacy of resistance breeding can be enhanced by molecular diagnostic tools, which result from knowledge of the molecular basis of resistance and susceptibility. Breeding uses resistance conferred by single R genes and polygenic quantitative resistance. The latter is partial but considered more durable. Molecular mechanisms of plant pathogen interactions are elucidated mainly in experimental systems involving single R genes, whereas most genes important for quantitative resistance in crops like potato are unknown. Quantitative resistance of potato to Phytophthora infestans causing late blight is often compromised by late plant maturity, a negative agronomic character. Our objective was to identify candidate genes for quantitative resistance to late blight not compromised by late plant maturity. We used diagnostic DNA-markers to select plants with different field levels of maturity corrected resistance (MCR) to late blight and compared their leaf transcriptomes before and after infection with P. infestans using SuperSAGE (serial analysis of gene expression) technology and next generation sequencing. We identified 2034 transcripts up or down regulated upon infection, including a homolog of the kiwi fruit allergen kiwellin. 806 transcripts showed differential expression between groups of genotypes with contrasting MCR levels. The observed expression patterns suggest that MCR is in part controlled by differential transcript levels in uninfected plants. Functional annotation suggests that, besides biotic and abiotic stress responses, general cellular processes such as photosynthesis, protein biosynthesis, and degradation play a role in MCR. PMID

  13. Upregulation of jasmonate biosynthesis and jasmonate-responsive genes in rice leaves in response to a bacterial pathogen mimic.

    PubMed

    Ranjan, Ashish; Vadassery, Jyothilakshmi; Patel, Hitendra Kumar; Pandey, Alok; Palaparthi, Ramesh; Mithöfer, Axel; Sonti, Ramesh V

    2015-05-01

    Xanthomonas oryzae pv. oryzae, the causal agent of bacterial blight of rice, secretes several cell wall degrading enzymes including cellulase (ClsA) and lipase/esterase (LipA). Prior treatment of rice leaves with purified cell wall degrading enzymes such as LipA can confer enhanced resistance against subsequent X. oryzae pv. oryzae infection. To understand LipA-induced rice defense responses, microarray analysis was performed 12 h after enzyme treatment of rice leaves. This reveals that 867 (720 upregulated and 147 downregulated) genes are differentially regulated (≥2-fold). A number of genes involved in defense, stress, signal transduction, and catabolic processes were upregulated while a number of genes involved in photosynthesis and anabolic processes were downregulated. The microarray data also suggested upregulation of jasmonic acid (JA) biosynthetic and JA-responsive genes. Estimation of various phytohormones in LipA-treated rice leaves demonstrated a significant increase in the level of JA-Ile (a known active form of JA) while the levels of other phytohormones were not changed significantly with respect to buffer-treated control. This suggests a role for JA-Ile in cell wall damage induced innate immunity. Furthermore, a comparative analysis of ClsA- and LipA-induced rice genes has identified key rice functions that might be involved in elaboration of damage-associated molecular pattern (DAMP)-induced innate immunity.

  14. The jasmonate pathway mediates salt tolerance in grapevines

    PubMed Central

    Ismail, Ahmed; Riemann, Michael; Nick, Peter

    2012-01-01

    Salt stress is a major constraint for many crop plants, such as the moderately salt-sensitive economically important fruit crop grapevine. Plants have evolved different strategies for protection against salinity and drought. Jasmonate signalling is a central element of both biotic and abiotic stress responses. To discriminate stress quality, there must be cross-talk with parallel signal chains. Using two grapevine cell lines differing in salt tolerance, the response of jasmonate ZIM/tify-domain (JAZ/TIFY) proteins (negative regulators of jasmonate signalling), a marker for salt adaptation Na+/H+ EXCHANGER (NHX1), and markers for biotic defence STILBENE SYNTHASE (StSy) and RESVERATROL SYNTHASE (RS) were analysed. It is shown that salt stress signalling shares several events with biotic defence including activity of a gadolinium-sensitive calcium influx channel (monitored by apoplastic alkalinization) and transient induction of JAZ/TIFY transcripts. Exogenous jasmonate can rescue growth in the salt-sensitive cell line. Suppression of jasmonate signalling by phenidone or aspirin blocks the induction of JAZ/TIFY transcripts. The rapid induction of RS and StSy characteristic for biotic defence in grapevine is strongly delayed in response to salt stress. In the salt-tolerant line, NHX1 is induced and the formation of reactive oxygen species, monitored as stress markers in the sensitive cell line, is suppressed. The data are discussed in terms of a model where salt stress signalling acts as a default pathway whose readout is modulated by a parallel signal chain triggered by biotic factors downstream of jasmonate signalling. PMID:22223808

  15. Distribution history and climatic controls of the Late Miocene Pikermian chronofauna

    PubMed Central

    Eronen, Jussi T.; Ataabadi, Majid Mirzaie; Micheels, Arne; Karme, Aleksis; Bernor, Raymond L.; Fortelius, Mikael

    2009-01-01

    The Late Miocene development of faunas and environments in western Eurasia is well known, but the climatic and environmental processes that controlled its details are incompletely understood. Here we map the rise and fall of the classic Pikermian fossil mammal chronofauna between 12 and 4.2 Ma, using genus-level faunal similarity between localities. To directly relate land mammal community evolution to environmental change, we use the hypsodonty paleoprecipitation proxy and paleoclimate modeling. The geographic distribution of faunal similarity and paleoprecipitation in successive timeslices shows the development of the open biome that favored the evolution and spread of the open-habitat adapted large mammal lineages. In the climate model run, this corresponds to a decrease in precipitation over its core area south of the Paratethys Sea. The process began in the latest Middle Miocene and climaxed in the medial Late Miocene, about 7–8 million years ago. The geographic range of the Pikermian chronofauna contracted in the latest Miocene, a time of increasing summer drought and regional differentiation of habitats in Eastern Europe and Southwestern Asia. Its demise at the Miocene-Pliocene boundary coincides with an environmental reversal toward increased humidity and forestation, changes inevitably detrimental to open-adapted, wide-ranging large mammals. PMID:19571012

  16. Distribution history and climatic controls of the Late Miocene Pikermian chronofauna.

    PubMed

    Eronen, Jussi T; Ataabadi, Majid Mirzaie; Micheels, Arne; Karme, Aleksis; Bernor, Raymond L; Fortelius, Mikael

    2009-07-21

    The Late Miocene development of faunas and environments in western Eurasia is well known, but the climatic and environmental processes that controlled its details are incompletely understood. Here we map the rise and fall of the classic Pikermian fossil mammal chronofauna between 12 and 4.2 Ma, using genus-level faunal similarity between localities. To directly relate land mammal community evolution to environmental change, we use the hypsodonty paleoprecipitation proxy and paleoclimate modeling. The geographic distribution of faunal similarity and paleoprecipitation in successive timeslices shows the development of the open biome that favored the evolution and spread of the open-habitat adapted large mammal lineages. In the climate model run, this corresponds to a decrease in precipitation over its core area south of the Paratethys Sea. The process began in the latest Middle Miocene and climaxed in the medial Late Miocene, about 7-8 million years ago. The geographic range of the Pikermian chronofauna contracted in the latest Miocene, a time of increasing summer drought and regional differentiation of habitats in Eastern Europe and Southwestern Asia. Its demise at the Miocene-Pliocene boundary coincides with an environmental reversal toward increased humidity and forestation, changes inevitably detrimental to open-adapted, wide-ranging large mammals.

  17. Weak climatic control of stand-scale fire history during the late holocene.

    PubMed

    Gavin, Daniel G; Hu, Feng Sheng; Lertzman, Kenneth; Corbett, Peter

    2006-07-01

    Forest fire occurrence is affected by multiple controls that operate at local to regional scales. At the spatial scale of forest stands, regional climatic controls may be obscured by local controls (e.g., stochastic ignitions, topography, and fuel loads), but the long-term role of such local controls is poorly understood. We report here stand-scale (<100 ha) fire histories of the past 5000 years based on the analysis of sediment charcoal at two lakes 11 km apart in southeastern British Columbia. The two lakes are today located in similar subalpine forests, and they likely have experienced the same late-Holocene climatic changes because of their close proximity. We evaluated two independent properties of fire history: (1) fire-interval distribution, a measure of the overall incidence of fire, and (2) fire synchroneity, a measure of the co-occurrence of fire (here, assessed at centennial to millennial time scales due to the resolution of sediment records). Fire-interval distributions differed between the sites prior to, but not after, 2500 yr before present. When the entire 5000-yr period is considered, no statistical synchrony between fire-episode dates existed between the two sites at any temporal scale, but for the last 2500 yr marginal levels of synchrony occurred at centennial scales. Each individual fire record exhibited little coherency with regional climate changes. In contrast, variations in the composite record (average of both sites) matched variations in climate evidenced by late-Holocene glacial advances. This was probably due to the increased sample size and spatial extent represented by the composite record (up to 200 ha) plus increased regional climatic variability over the last several millennia, which may have partially overridden local, non-climatic controls. We conclude that (1) over past millennia, neighboring stands with similar modern conditions may have experienced different fire intervals and asynchronous patterns in fire episodes, likely

  18. [THE IMPROVEMENT OF CITIES AND SANITARY CONTROL IN RUSSIA IN LATE XIX--EARLY XX CENTURIES].

    PubMed

    Sherstneva, E V

    2015-01-01

    The article considers activity of municipal self-governments of Russia concerning support of sanitary epidemiological well-being of cities in the late XIX--early XX centuries. The acuteness of problem of sanitary conditions of urban settlements particularly became visible in post-reform period due to increasing of number of urban population, alteration of setup and rhythm of life in cities, appearance of new forms of worker's daily chores. Al this, against the background of underdevelopment of communal sphere aggravated epidemiological situation in cities. The impulse to improvement and development of sanitary control was made by the city regulations of 1870 presenting to town authorities the right to deal with sanitary issues. The significant input into improvement of cities was made first of all at the expense of construction of water supplies and sewerage and support of sanitary control of these spheres of municipal economy. Under town councils of many cities the sanitary commissions were organized to support permanent sanitary control in town. The development of town sanitation followed the way of specialization. The housing and communal, trade and food, school and sanitary and sanitary and veterinary control were organized.

  19. Jasmonates are essential factors inducing gummosis in tulips: mode of action of jasmonates focusing on sugar metabolism.

    PubMed

    Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

    2005-05-01

    The purpose of this study was to know the mechanism of jasmonates to induce gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) shoots, especially on the focus of sugar metabolism. Gummosis in the first internode of tulip plants was induced by the application of methyl jasmonate (JA-Me, 1% w/w in lanolin) and jasmonic acid (JA, 1% w/w in lanolin) 5 days after application and strongly stimulated by the simultaneous application of ethylene-releasing compound, ethephon (2-chloroethylphosphonic acid, 1% w/w in lanolin), although ethephon alone had little effect. JA-Me stimulated ethylene production of the first internodes of tulips, ethylene production increasing up to more than 5 times at day 1 and day 3 after the application. On the other hand, application of ethephon did not increase endogenous levels of jasmonates in tulip stems. Analysis of composition of tulip gums revealed that they were consisted of glucuronoarabinoxylan with an average molecular weight of ca. 700 kDa. JA-Me strongly decreased the total amount of soluble sugars in tulip stems even in 1 day after application, being ca. 50% of initial values 5 days after application, but ethephon did not. However, both JA-Me and ethephon had almost no effect on the neutral sugar compositions of soluble sugars mainly consisting of glucose, mannose and xylose in ratio of 20:2:1 and traces of arabinose. Both JA-Me and ethephon applied exogenously stimulated senescence of tulip shoots shown by the loss of chlorophyll. These results strongly suggest that the essential factor of gummosis in tulips is jasmonates affecting the sugar metabolism in tulip shoots. The mode of action of jasmonates to induce gummosis of tulip shoots is discussed in relation to ethylene production, sugar metabolism and senescence.

  20. Environmentally controlled succession in a late Pleistocene coral reef (Sinai, Egypt)

    NASA Astrophysics Data System (ADS)

    Mewis, H.; Kiessling, W.

    2013-03-01

    The concept of ecological succession has been frequently applied in the study of ancient reefs. Whereas Paleozoic and Mesozoic reefs are commonly thought to reveal an autogenic primary—climax zonation, patterns in Neogene and Quaternary reefs are much more diverse. Here, we describe a well-preserved late Pleistocene coral reef from Dahab on Sinai Peninsula (Egypt), which shows a distinct zonation that resembles an ecological succession. In contrast to classical examples of ecological successions, species composition, paleoenvironmental conditions, and coral biodiversity of the Dahab reef indicate an allogenic, sea-level controlled community change, from marginal marine to reef slope and back reef. A review of the literature confirms that autogenic, short-term successions are virtually absent in Quaternary reefs. We predict that long generation times of corals make it unlikely that classical autogenic successions develop in reefs at all, unless environmental conditions are unusually stable.

  1. Abortion in late Imperial China: routine birth control or crisis intervention?

    PubMed

    Sommer, Matthew H

    2010-01-01

    In late imperial China, a number of purported methods of abortion were known; but who actually attempted abortion and under what circumstances? Some historians have suggested that abortion was used for routine birth control, which presupposes that known methods were safe, reliable, and readily available. This paper challenges the qualitative evidence on which those historians have relied, and presents new evidence from Qing legal sources and modern medical reports to argue that traditional methods of abortion (the most common being abortifacient drugs) were dangerous, unreliable, and often cost a great deal of money. Therefore, abortion in practice was an emergency intervention in a crisis: either a medical crisis, in which pregnancy threatened a woman's health, or a social crisis, in which pregnancy threatened to expose a woman's extramarital sexual relations. Moreover, abortion was not necessarily available even to women who wanted one.

  2. Jasmonate-mediated induced volatiles in the American cranberry, Vaccinium macrocarpon: from gene expression to organismal interactions

    USDA-ARS?s Scientific Manuscript database

    Jasmonates, i.e., jasmonic acid (JA) and methyl jasmonate (MeJA), are signaling hormones that regulate a large number of defense responses in plants which in turn affect the plants’ interactions with herbivores and their natural enemies. Here, we investigated the effect of jasmonates on the emissio...

  3. Production and function of jasmonates in nodulated roots of soybean plants inoculated with Bradyrhizobium japonicum.

    PubMed

    Costanzo, María Emilia; Andrade, Andrea; del Carmen Tordable, María; Cassán, Fabricio; Abdala, Guillermina

    2012-10-01

    Little is known regarding production and function of endogenous jasmonates (JAs) in root nodules of soybean plants inoculated with Bradyrhizobium japonicum. We investigated (1) production of jasmonic acid (JA) and 12-oxophytodienoic acid (OPDA) in roots of control and inoculated plants and in isolated nodules; (2) correlations between JAs levels, nodule number, and plant growth during the symbiotic process; and (3) effects of exogenous JA and OPDA on nodule cell number and size. In roots of control plants, JA and OPDA levels reached a maximum at day 18 after inoculation; OPDA level was 1.24 times that of JA. In roots of inoculated plants, OPDA peaked at day 15, whereas JA level did not change appreciably. Shoot dry matter of inoculated plants was higher than that of control at day 21. Chlorophyll a decreased more abruptly in control plants than in inoculated plants, whereas b decreased gradually in both cases. Exogenous JA or OPDA changed number and size of nodule central cells and peripheral cells. Findings from this and previous studies suggest that increased levels of JA and OPDA in control plants are related to senescence induced by nutritional stress. OPDA accumulation in nodulated roots suggests its involvement in "autoregulation of nodulation."

  4. Methyl jasmonate mediates upregulation of bacoside A production in shoot cultures of Bacopa monnieri.

    PubMed

    Sharma, Poojadevi; Yadav, Sheetal; Srivastava, Anshu; Shrivastava, Neeta

    2013-07-01

    Methyl jasmonate (MJ) enhances the production of a range of secondary metabolites including triterpenoid saponins in a variety of plant species. Here, it enhanced production of bacoside A, a valuable triterpenoid saponin having nootropic therapeutic activity in in vitro shoot cultures of Bacopa monnieri, the only known source of bacoside A. The highest yield was with 50 μM MJ giving 4.4 mg bacoside A/g dry wt; an 1.8-fold increase (compared to control) after 1 week.

  5. Longitudinal Brain Volume Changes in Preterm and Term Control Subjects During Late Childhood and Adolescence

    PubMed Central

    Ment, Laura R.; Kesler, Shelli; Vohr, Betty; Katz, Karol H.; Baumgartner, Heidi; Schneider, Karen C.; Delancy, Susan; Silbereis, John; Duncan, Charles C.; Constable, R. Todd; Makuch, Robert W.; Reiss, Allan L.

    2009-01-01

    OBJECTIVE Although preterm very low birth weight infants have a high prevalence of neuroanatomical abnormalities when evaluated at term-equivalent age, patterns of brain growth in prematurely born infants during school age and adolescence remain largely unknown. Our goal was to test the hypothesis that preterm birth results in long-term dynamic changes in the developing brain. METHODS We performed serial volumetric MRI studies at ages 8 and 12 years in 55 preterm infants born weighing 600 to 1250 g and 20 term control children who participated in the follow-up component of a prospective, randomized, placebo-controlled intraventricular hemorrhage prevention study. RESULTS Total brain volumes increased 2% to 3% between the ages of 8 and 12 years for both preterm and term children. These changes involved reductions in cerebral gray matter while white matter increased. Between 8 and 12 years of age, preterm subjects experienced a 2% decrease in left cerebral gray matter compared with a 10% reduction in left cerebral gray for term controls. For right cerebral gray matter, preterm children experienced a 3% decrease in volume between years 8 and 12, compared with 9% for term controls (group-by-time). In contrast, preterm subjects had a 10% increase in cerebral white matter volumes bilaterally between ages 8 and 12 years, compared with >26% increases for both hemispheres for term controls. Significant differences in regional volume changes between study groups were found in bilateral temporal gray and in parietal white matter. CONCLUSIONS Preterm birth continues to perturb the trajectory of cerebral development during late childhood and early adolescence with preterm children, showing both lower gray matter reduction and less white matter gain over time compared with term control subjects. PMID:19171615

  6. Optimized Jasmonic Acid Production by Lasiodiplodia theobromae Reveals Formation of Valuable Plant Secondary Metabolites

    PubMed Central

    Eng, Felipe; Haroth, Sven; Feussner, Kirstin; Meldau, Dorothea; Rekhter, Dmitrij; Ischebeck, Till; Brodhun, Florian

    2016-01-01

    Jasmonic acid is a plant hormone that can be produced by the fungus Lasiodiplodia theobromae via submerged fermentation. From a biotechnological perspective jasmonic acid is a valuable feedstock as its derivatives serve as important ingredients in different cosmetic products and in the future it may be used for pharmaceutical applications. The objective of this work was to improve the production of jasmonic acid by L. theobromae strain 2334. We observed that jasmonic acid formation is dependent on the culture volume. Moreover, cultures grown in medium containing potassium nitrate as nitrogen source produced higher amounts of jasmonic acid than analogous cultures supplemented with ammonium nitrate. When cultivated under optimal conditions for jasmonic acid production, L. theobromae secreted several secondary metabolites known from plants into the medium. Among those we found 3-oxo-2-(pent-2-enyl)-cyclopentane-1-butanoic acid (OPC-4) and hydroxy-jasmonic acid derivatives, respectively, suggesting that fungal jasmonate metabolism may involve similar reaction steps as that of plants. To characterize fungal growth and jasmonic acid-formation, we established a mathematical model describing both processes. This model may form the basis of industrial upscaling attempts. Importantly, it showed that jasmonic acid-formation is not associated to fungal growth. Therefore, this finding suggests that jasmonic acid, despite its enormous amount being produced upon fungal development, serves merely as secondary metabolite. PMID:27907207

  7. Optimized Jasmonic Acid Production by Lasiodiplodia theobromae Reveals Formation of Valuable Plant Secondary Metabolites.

    PubMed

    Eng, Felipe; Haroth, Sven; Feussner, Kirstin; Meldau, Dorothea; Rekhter, Dmitrij; Ischebeck, Till; Brodhun, Florian; Feussner, Ivo

    2016-01-01

    Jasmonic acid is a plant hormone that can be produced by the fungus Lasiodiplodia theobromae via submerged fermentation. From a biotechnological perspective jasmonic acid is a valuable feedstock as its derivatives serve as important ingredients in different cosmetic products and in the future it may be used for pharmaceutical applications. The objective of this work was to improve the production of jasmonic acid by L. theobromae strain 2334. We observed that jasmonic acid formation is dependent on the culture volume. Moreover, cultures grown in medium containing potassium nitrate as nitrogen source produced higher amounts of jasmonic acid than analogous cultures supplemented with ammonium nitrate. When cultivated under optimal conditions for jasmonic acid production, L. theobromae secreted several secondary metabolites known from plants into the medium. Among those we found 3-oxo-2-(pent-2-enyl)-cyclopentane-1-butanoic acid (OPC-4) and hydroxy-jasmonic acid derivatives, respectively, suggesting that fungal jasmonate metabolism may involve similar reaction steps as that of plants. To characterize fungal growth and jasmonic acid-formation, we established a mathematical model describing both processes. This model may form the basis of industrial upscaling attempts. Importantly, it showed that jasmonic acid-formation is not associated to fungal growth. Therefore, this finding suggests that jasmonic acid, despite its enormous amount being produced upon fungal development, serves merely as secondary metabolite.

  8. Urine metabolomics in neonates with late-onset sepsis in a case-control study

    NASA Astrophysics Data System (ADS)

    Sarafidis, Kosmas; Chatziioannou, Anastasia Chrysovalantou; Thomaidou, Agathi; Gika, Helen; Mikros, Emmanouel; Benaki, Dimitra; Diamanti, Elisavet; Agakidis, Charalampos; Raikos, Nikolaos; Drossou, Vasiliki; Theodoridis, Georgios

    2017-04-01

    Although late-onset sepsis (LOS) is a major cause of neonatal morbidity and mortality, biomarkers evaluated in LOS lack high diagnostic accuracy. In this prospective, case-control, pilot study, we aimed to determine the metabolic profile of neonates with LOS. Urine samples were collected at the day of initial LOS evaluation, the 3rd and 10th day, thereafter, from 16 septic neonates (9 confirmed and 7 possible LOS cases) and 16 non-septic ones (controls) at respective time points. Urine metabolic profiles were assessed using non-targeted nuclear magnetic resonance spectroscopy and targeted liquid chromatography-tandem mass spectrometry analysis. Multivariate statistical models with data from either analytical approach showed clear separation between the metabolic profiles of septic neonates (both possible and confirmed) and the controls. Metabolic changes appeared to be related to disease progression. Overall, neonates with confirmed or possible LOS exhibited comparable metabolic profiles indicating similar metabolic alternations upon the onset of clinical manifestations. This methodology therefore enabled the discrimination of neonates with LOS from non-septic individuals, providing potential for further research toward the discovery of LOS-related biomarkers.

  9. Urine metabolomics in neonates with late-onset sepsis in a case-control study

    PubMed Central

    Sarafidis, Kosmas; Chatziioannou, Anastasia Chrysovalantou; Thomaidou, Agathi; Gika, Helen; Mikros, Emmanouel; Benaki, Dimitra; Diamanti, Elisavet; Agakidis, Charalampos; Raikos, Nikolaos; Drossou, Vasiliki; Theodoridis, Georgios

    2017-01-01

    Although late-onset sepsis (LOS) is a major cause of neonatal morbidity and mortality, biomarkers evaluated in LOS lack high diagnostic accuracy. In this prospective, case-control, pilot study, we aimed to determine the metabolic profile of neonates with LOS. Urine samples were collected at the day of initial LOS evaluation, the 3rd and 10th day, thereafter, from 16 septic neonates (9 confirmed and 7 possible LOS cases) and 16 non-septic ones (controls) at respective time points. Urine metabolic profiles were assessed using non-targeted nuclear magnetic resonance spectroscopy and targeted liquid chromatography-tandem mass spectrometry analysis. Multivariate statistical models with data from either analytical approach showed clear separation between the metabolic profiles of septic neonates (both possible and confirmed) and the controls. Metabolic changes appeared to be related to disease progression. Overall, neonates with confirmed or possible LOS exhibited comparable metabolic profiles indicating similar metabolic alternations upon the onset of clinical manifestations. This methodology therefore enabled the discrimination of neonates with LOS from non-septic individuals, providing potential for further research toward the discovery of LOS-related biomarkers. PMID:28374757

  10. Benefits of jasmonate-dependent defenses against vertebrate herbivores in nature.

    PubMed

    Machado, Ricardo Ar; McClure, Mark; Hervé, Maxime R; Baldwin, Ian T; Erb, Matthias

    2016-06-29

    Endogenous jasmonates are important regulators of plant defenses. If and how they enable plants to maintain their reproductive output when facing community-level herbivory under natural conditions, however, remains unknown. We demonstrate that jasmonate-deficient Nicotiana attenuata plants suffer more damage by arthropod and vertebrate herbivores than jasmonate-producing plants in nature. However, only damage by vertebrate herbivores translates into a significant reduction in flower production. Vertebrate stem peeling has the strongest negative impact on plant flower production. Stems are defended by jasmonate-dependent nicotine, and the native cottontail rabbit Sylvilagus nuttallii avoids jasmonate-producing N. attenuata shoots because of their high levels of nicotine. Thus, endogenous jasmonates enable plants to resist different types of herbivores in nature, and jasmonate-dependent defenses are important for plants to maintain their reproductive potential when facing vertebrate herbivory. Ecological and evolutionary models on plant defense signaling should aim at integrating arthropod and vertebrate herbivory at the community level.

  11. Ehancing disease resistance in peach fruit with methyl jasmonate

    USDA-ARS?s Scientific Manuscript database

    The effect of methyl jasmonate (MeJA) on postharvest diseases caused by P. expansum, B. cinerea and R. stolonifer in peach fruit (Prunus persica Batsch cv Dahebai) and the possible mechanisms involved were investigated. Peaches were harvested at the firm-mature stage and treated with 1 or 500 µmol/L...

  12. Roles for blue light, jasmonate and nitric oxide in the regulation of dormancy and germination in wheat grain (Triticum aestivum L.).

    PubMed

    Jacobsen, John V; Barrero, Jose M; Hughes, Trijntje; Julkowska, Magdalena; Taylor, Jennifer M; Xu, Qian; Gubler, Frank

    2013-07-01

    Abscisic acid (ABA) plays a central role in seed dormancy and transcriptional regulation of genes coding for ABA biosynthetic and degradation enzymes is responsible for control of ABA content. However, little is known about signalling both before and after ABA regulation, in particular, how environmental signals are perceived and transduced. We are interested in these processes in cereal grains, particularly in relation to the development of strategies for controlling pre-harvest sprouting in barley and wheat. Our previous studies have indicated possible components of dormancy control and here we present evidence that blue light, nitric oxide (NO) and jasmonate are major controlling elements in wheat grain. Using microarray and pharmacological studies, we have found that blue light inhibits germination in dormant grain and that methyl jasmonate (MJ) and NO counteract this effect by reducing dormancy. We also present evidence that NO and jasmonate play roles in dormancy control in vivo. ABA was reduced by MJ and this was accompanied by reduced levels of expression of TaNCED1 and increased expression of TaABA8'OH-1 compared with dormant grain. Similar changes were caused by after-ripening. Analysis of global gene expression showed that although jasmonate and after-ripening caused important changes in gene expression, the changes were very different. While breaking dormancy, MJ had only a small number of target genes including gene(s) encoding beta-glucosidase. Our evidence indicates that NO and MJ act interdependently in controlling reduction of ABA and thus the demise of dormancy.

  13. Late Recovery from Stuttering: The Role of Hand Dominancy, Fine Motor and ‎Inhibition Control.

    PubMed

    Mohammadi, Hiwa; Khazaie, Habibolah; Rezaei, Mansour; Joghataei, Mohammad Taghi

    2016-01-01

    There are controversial reports about factors that affect recovery from stuttering. In the ‎present study, the effect of hand dominancy, fine motor and inhibition control on late ‎recovery from stuttering was investigated among a group of Kurdish-Persian children who ‎stuttered in Iran.‎ Twenty-two Kurdish-Persian children aged 7-14 years who stuttered were followed for 6 ‎years. Based on the evaluation of three experienced speech therapists and parental judgments, ‎these children were classified into recovered or persistent groups. Data about fine motor ‎control of hand and inhibition control were obtained, using Purdue Pegboard and Victoria ‎Strop Color Word Tests, respectively. Risk factors including sex, age, and family history of ‎stuttering, handedness, inhibitory control and fine motor control of hand were compared ‎between the groups and modeled to predict recovery from stuttering using logistic regression.‎ From the 22 participants, 5 (22.7%) recovered from stuttering. The recovered and persistent ‎groups did not show significant differences in the interference effect. By dividing the scores ‎of the Purdue Pegboard tests to the right and left hand, we created a new Handedness Index ‎‎(HI). HI was significantly higher in the recovered group. The score of right hand was higher ‎than the left in the recovered group, but no difference was found between the two hands in ‎the persistent group. Among the investigated risk factors, only HI could predict the recovery ‎from or persistency of stuttering with 94% sensitivity and 84% specificity.‎ Handedness Index can predict the recovery from stuttering significantly among children who ‎stutter.‎.

  14. Orbital control on the timing of oceanic anoxia in the Late Cretaceous

    NASA Astrophysics Data System (ADS)

    Batenburg, Sietske; De Vleeschouwer, David; Sprovieri, Mario; Hilgen, Frederik; Gale, Andrew; Singer, Brad; Koeberl, Christian; Cocioni, Rodolfo; Claeys, Philippe; Montanari, Alessandro

    2015-04-01

    The oceans of the Cenomanian-Turonian transition, at the height of the Cretaceous greenhouse, were abruptly disturbed by a period of oceanic anoxia. This led to the brief but widespread deposition of black organic-rich shales in the world's oceans, such as the Livello Bonarelli in the Umbria-Marche Basin (Italy). However, the origin and exact timing of the onset of oceanic anoxia are debated. We present a 6-Myr-long astronomically-tuned timescale across the Cenomanian-Turonian Oceanic Anoxic Event 2 (OAE2), obtained from the Furlo and Bottaccione sections in the Umbria-Marche Basin. The cyclic climatic imprint on lithological, geophysical and stable isotope records allows us to decipher the relationship between orbital forcing and the Late Cretaceous carbon cycle. The deposition of black shales and cherts, as well as the onset of oceanic anoxia, is related to maxima in the 405-thousand year cycle of eccentricity modulated precession. In this study, we also present a new radioisotopic Ar/Ar age for the Thatcher bentonite occurring within the mid-Cenomanian carbon isotope event in the Western Interior of the USA. We correlate our astrochronology from the Umbria-Marche Basin to this new and recent radioisotopic ages, and we come to an unprecedented age control for European successions. The most likely tuned age for the Livello Bonarelli base is 94.22 Ma, however a 405-kyr older age cannot be excluded due to increasing uncertainties in stratigraphic correlation, radioisotopic dating, and orbital configuration. Although volcanism was probably the ultimate driver of OAE2, the cyclicity of the Umbria-Marche successions reveals that the exact timing of carbon cycle perturbations in the Late Cretaceous was determined by orbital periodicities.

  15. Late-phase miRNA-controlled oncolytic adenovirus for selective killing of cancer cells

    PubMed Central

    Fillat, Cristina

    2015-01-01

    Tissue-specific detargeting by miRNAs has been demonstrated to be a potent strategy to restrict adenoviral replication to cancer cells. These studies have generated adenoviruses with miRNA target sites placed in the 3′UTR of early gene products. In this work, we have studied the feasibility of providing tissue-specific selectivity to replication-competent adenoviruses through the regulation of the late structural protein fiber (L5 gene). We have engineered a 3′UTR containing eight miR-148a binding sites downstream the L5 coding sequence (Ad-L5-8miR148aT). We present in vitro and in vivo evidences of Ad-L5-8miR148aT miRNA-dependent regulation. In vitro data show that at 72 hours post-infection miR-148a-regulation impaired fiber expression leading to a 70% reduction of viral release. The application of seven consecutive rounds of infection in miR-148a cells resulted in 10.000-fold reduction of viral genomes released. In vivo, liver production of infective viral particles was highly impaired, similarly to that triggered by an adenovirus with miRNA target sites regulating the early E1A gene. Noticeably, mice treated with Ad-L5-8miR148aT showed an attenuation of adenoviral-induced hepatotoxicity but retained full lytic activity in cancer cells and exhibited robust antitumoral responses in patient-derived xenografts. Thus, miRNA-control of late proteins constitutes a novel strategy to provide selectivity to adenoviruses. PMID:25714032

  16. Multinational case-control study of risk factors for the development of late invasive pulmonary aspergillosis following kidney transplantation.

    PubMed

    López-Medrano, F; Fernández-Ruiz, M; Silva, J T; Carver, P L; van Delden, C; Merino, E; Pérez-Saez, M J; Montero, M; Coussement, J; de Abreu Mazzolin, M; Cervera, C; Santos, L; Sabé, N; Scemla, A; Cordero, E; Cruzado-Vega, L; Martín-Moreno, P L; Len, Ó; Rudas, E; Ponce de León, A; Arriola, M; Lauzurica, R; David, M D; González-Rico, C; Henríquez-Palop, F; Fortún, J; Nucci, M; Manuel, O; Paño-Pardo, J R; Montejo, M; Vena, A; Sánchez-Sobrino, B; Mazuecos, A; Pascual, J; Horcajada, J P; Lecompte, T; Moreno, A; Carratalà, J; Blanes, M; Hernández, D; Hernández-Méndez, E A; Fariñas, M C; Perelló-Carrascosa, M; Muñoz, P; Andrés, A; Aguado, J M

    2017-06-23

    To assess the risk factors for development of late-onset invasive pulmonary aspergillosis (IPA) after kidney transplantation (KT). We performed a multinational case-control study that retrospectively recruited 112 KT recipients diagnosed with IPA between 2000 and 2013. Controls were matched (1:1 ratio) by centre and date of transplantation. Immunosuppression-related events (IREs) included the occurrence of non-ventilator-associated pneumonia, tuberculosis, cytomegalovirus disease, and/or de novo malignancy. We identified 61 cases of late (>180 days after transplantation) IPA from 24 participating centres (accounting for 54.5% (61/112) of all cases included in the overall study). Most diagnoses (54.1% (33/61)) were established within the first 36 post-transplant months, although five cases occurred more than 10 years after transplantation. Overall mortality among cases was 47.5% (29/61). Compared with controls, cases were significantly older (p 0.010) and more likely to have pre-transplant chronic obstructive pulmonary disease (p 0.001) and a diagnosis of bloodstream infection (p 0.016) and IRE (p <0.001) within the 6 months prior to the onset of late IPA. After multivariate adjustment, previous occurrence of IRE (OR 19.26; 95% CI 2.07-179.46; p 0.009) was identified as an independent risk factor for late IPA. More than half of IPA cases after KT occur beyond the sixth month, with some of them presenting very late. Late IPA entails a poor prognosis. We identified some risk factors that could help the clinician to delimit the subgroup of KT recipients at the highest risk for late IPA. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  17. Plants on constant alert: elevated levels of jasmonic acid and jasmonate-induced transcripts in caterpillar resistant maize

    USDA-ARS?s Scientific Manuscript database

    Plant defense responses against insect herbivores frequently depend on the biosynthesis and action of jasmonic acid (JA) and its conjugates. To better understand JA signaling pathways in maize (Zea mays L.), we have examined two maize genotypes, Mp708 and Tx601. Mp708 is resistant to feeding by le...

  18. Continuous exposure to the deterrents cis-jasmone and methyl jasmonate does not alter the behavioural responses of Frankliniella occidentalis

    PubMed Central

    Egger, Barbara; Spangl, Bernhard; Koschier, Elisabeth Helene

    2016-01-01

    Behavioural responses of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a generalist, cell sap-feeding insect species with piercing-sucking mouthparts, after continuous exposure to two deterrent secondary plant compounds are investigated. We compared in choice assays on bean leaf discs, the settling, feeding, and oviposition preferences of F. occidentalis females that had no experience with the two fatty acid derivatives methyl jasmonate and cis-jasmone before testing (naïve thrips) vs. females that had been exposed to the deterrent compounds before testing (experienced thrips). The thrips were exposed to the deterrents at low or high concentrations for varied time periods and subsequently tested on bean leaf discs treated with the respective deterrent at either a low or a high concentration. Frankliniella occidentalis females avoided settling on the deterrent-treated bean leaf discs for an observation period of 6 h, independent of their previous experience. Our results demonstrate that feeding and oviposition deterrence of the jasmonates to the thrips were not altered by continuous exposure of the thrips to the jasmonates. Habituation was not induced, neither by exposure to the low concentration of the deterrents nor by exposure to the high concentration. These results indicate that the risk of habituation to two volatile deterrent compounds after repeated exposure is not evident in F. occidentalis. This makes the two compounds potential candidates to be integrated in pest management strategies. PMID:26726263

  19. Jasmonate signaling in the field, part I: elicited changes in jasmonate pools of transgenic Nicotiana attenuata populations.

    PubMed

    Gaquerel, Emmanuel; Stitz, Michael; Kallenbach, Mario; Baldwin, Ian T

    2013-01-01

    Nicotiana attenuata, a wild tobacco species native of the southwestern USA that grows in the immediate postfire environment, is one of the important host plants for herbivore populations recolonizing recently burned habitats in the Great Basin Desert. Based on more than 20 years of field research on this eco-genomics model system established in our group, we have developed a genetic and analytical toolbox that allows us to assess the importance of particular genes and metabolites for the survival of this plant in its native habitat. This toolbox has been extensively applied to study the activation of jasmonate signaling after the attack of different herbivore species. Here, we provide detailed guidelines for the analysis, under field conditions, of induced changes in jasmonate pools during insect herbivory. The procedures range from selection and field release of well-characterized transgenic lines for testing the physiological consequences of manipulating jasmonate biogenesis, metabolism, or perception to the metabolic elicitation of chewing herbivore attack and the quantification of the resulting changes in jasmonate fluxes.

  20. Deciphering natural to anthropogenic control on sedimentation: the Late Holocene Magdala (Kinneret Lake, Israel) harbour hystory

    NASA Astrophysics Data System (ADS)

    Sarti, G.; Rossi, V.; Amorosi, A.; Bertoni, D.; Ribolini, A.; Sammartino, I.; Zanchetta, G.

    2012-04-01

    Using a multidisciplinary approach involving geologists, geomorphologists and archeologists, the late Holocene sedimentary succession buried beneath the ancient Magdala harbour area (Kinneret Lake, Israel) was studied, in order to highlight the strict relationships among harbour evolutive phases (e.g. foundation, siltation, abandonment), natural events (e.g. sea-level variations, climatic changes and earthquakes among the most important) and, obviously, archaeological history. Recent excavations performed within the "Magdala Project" have discovered a harbour structure with late Hellenistic-Roman mooring stones at altitudes of 208.100 m and 208.320 m bsl respectively, suggestive of a higher lake-level (about 212 m bsl) than previously hypothesized. Along the most representative sections of trenches, integrated sedimentological, micropalaeontological (benthic meiofauna and pollen) and geochemical analyses were carried out on sedimentary deposits underlying and overlying the harbour structures, to define the main depositional facies and evolution phases that took place during the last millennia. Spatial variability of coeval palaeoenvironments across the archaeological site allowed to reconstruct a comprehensive picture of the harbour complex, evidencing the occurrence of three main evolution phases, similar to those reported from several Mediterranean Sea harbour systems: 1) a pre-harbor foundation phase; 2) a sin-harbor activity phase and 3) an harbor-abandonment phase. The first phase corresponds to the development of a natural lacustrine sandy beach barren in archaeological remains and containing an ostracod fauna very similar to the one observed within the present-day lake basin at ca. 5 m water depth. The second phase was characterized by the formation of an early Hellenistic sheltered lacustrine basin, recording the first anthropogenic control exerted on coastal sedimentation by the construction of harbour structures ("anthropogenically forced sheltered basin

  1. Identification of a Bipartite Jasmonate-Responsive Promoter Element in the Catharanthus roseus ORCA3 Transcription Factor Gene That Interacts Specifically with AT-Hook DNA-Binding Proteins1[W

    PubMed Central

    Vom Endt, Débora; Soares e Silva, Marina; Kijne, Jan W.; Pasquali, Giancarlo; Memelink, Johan

    2007-01-01

    Jasmonates are plant signaling molecules that play key roles in defense against certain pathogens and insects, among others, by controlling the biosynthesis of protective secondary metabolites. In Catharanthus roseus, the APETALA2-domain transcription factor ORCA3 is involved in the jasmonate-responsive activation of terpenoid indole alkaloid biosynthetic genes. ORCA3 gene expression is itself induced by jasmonate. By loss- and gain-of-function experiments, we located a 74-bp region within the ORCA3 promoter, which contains an autonomous jasmonate-responsive element (JRE). The ORCA3 JRE is composed of two important sequences: a quantitative sequence responsible for a high level of expression and a qualitative sequence that appears to act as an on/off switch in response to methyl jasmonate. We isolated 12 different DNA-binding proteins having one of four different types of DNA-binding domains, using the ORCA3 JRE as bait in a yeast (Saccharomyces cerevisiae) one-hybrid transcription factor screening. The binding of one class of proteins bearing a single AT-hook DNA-binding motif was affected by mutations in the quantitative sequence within the JRE. Two of the AT-hook proteins tested had a weak activating effect on JRE-mediated reporter gene expression, suggesting that AT-hook family members may be involved in determining the level of expression of ORCA3 in response to jasmonate. PMID:17496112

  2. Jasmonic Acid Oxidase 2 Hydroxylates Jasmonic Acid and Represses Basal Defense and Resistance Responses against Botrytis cinerea Infection.

    PubMed

    Smirnova, Ekaterina; Marquis, Valentin; Poirier, Laure; Aubert, Yann; Zumsteg, Julie; Ménard, Rozenn; Miesch, Laurence; Heitz, Thierry

    2017-09-12

    Jasmonates (JAs) orchestrate immune responses upon wound/herbivore injury or infection by necrotrophic pathogens. Elucidation of catabolic routes has revealed new complexity in jasmonate metabolism. Two integrated pathways attenuate signaling by turning over the active hormone jasmonoyl-isoleucine (JA-Ile) through ω-oxidation or deconjugation, and define an indirect route forming the derivative 12OH-JA. Here, we provide evidence for a second 12OH-JA formation pathway by direct jasmonic acid (JA) oxidation. Three jasmonic acid oxidases (JAOs) of the 2-oxoglutarate dioxygenase family catalyze specific oxidation of JA to 12OH-JA, and their genes are induced by wounding or infection by the fungus Botrytis cinerea. JAO2 exhibits the highest basal expression, and its deficiency in jao2 mutants strongly enhanced antifungal resistance. The resistance phenotype resulted from constitutive expression of antimicrobial markers rather than from their higher induction in infected jao2 plants and could be reversed by ectopic expression of any of the three JAOs in jao2. Elevated defense in jao2 was dependent on the activity of JASMONATE RESPONSE 1 (JAR1) and CORONATINE-INSENSITIVE 1 (COI1) but was not correlated with enhanced JA-Ile accumulation. Instead, jao2 mutant lines displayed altered accumulation of several JA species in healthy and challenged plants, suggesting elevated metabolic flux through JA-Ile. Collectively, these data identify the missing enzymes hydroxylating JA and uncover an important metabolic diversion mechanism for repressing basal JA defense responses. Copyright © 2017 The Author. Published by Elsevier Inc. All rights reserved.

  3. Jasmonates are phytohormones with multiple functions, including plant defense and reproduction.

    PubMed

    Avanci, N C; Luche, D D; Goldman, G H; Goldman, M H S

    2010-03-16

    The plant hormones jasmonic acid and methyl jasmonate, along with their intermediate compounds, produced in the octadecanoid pathway, are important signaling molecules that are collectively called jasmonates. These are widespread in the plant kingdom and play crucial roles in biotic/abiotic stress responses, as well as in processes related to plant growth and development. Recently, it has been shown that jasmonates are also involved in reproductive processes. We present the most recent findings related to the biosynthesis, regulation and signaling mechanisms of jasmonates. Additionally, we discuss the identification of [(+)-7-iso-JA-L-Ile] as the active biological hormonal form of jasmonate; this fills the greatest gap in our knowledge about the signaling mechanism that is responsible for the activation of downstream genes in the jasmonate-signaling cascade. The identification of several Arabidopsis thaliana mutants was crucial to the elucidation of the signaling mechanisms involved in jasmonate-mediated responses. Finally, the involvement of jasmonates in the reproductive process of Nicotiana tabacum L. is briefly discussed, since some of the main enzymes of the jasmonic acid biosynthesis pathway were identified in a stigma/style expressed sequence tag database (TOBEST) of this Solanaceae species.

  4. Transporter-Mediated Nuclear Entry of Jasmonoyl-Isoleucine Is Essential for Jasmonate Signaling.

    PubMed

    Li, Qingqing; Zheng, Jian; Li, Shuaizhang; Huang, Guanrong; Skilling, Stephen J; Wang, Lijian; Li, Ling; Li, Mengya; Yuan, Lixing; Liu, Pei

    2017-02-05

    To control gene expression by directly responding to hormone concentrations, both animal and plant cells have exploited comparable mechanisms to sense small-molecule hormones in nucleus. Whether nuclear entry of these hormones is actively transported or passively diffused, as conventionally postulated, through the nuclear pore complex, remains enigmatic. Here, we identified and characterized a jasmonate transporter in Arabidopsis thaliana, AtJAT1/AtABCG16, which exhibits an unexpected dual localization at the nuclear envelope and plasma membrane. We show that AtJAT1/AtABCG16 controls the cytoplasmic and nuclear partition of jasmonate phytohormones by mediating both cellular efflux of jasmonic acid (JA) and nuclear influx of jasmonoyl-isoleucine (JA-Ile), and is essential for maintaining a critical nuclear JA-Ile concentration to activate JA signaling. These results illustrate that transporter-mediated nuclear entry of small hormone molecules is a new mechanism to regulate nuclear hormone signaling. Our findings provide an avenue to develop pharmaceutical agents targeting the nuclear entry of small molecules.

  5. The efficacy of Beauveria bassiana, jasmonic acid and chlorantraniliprole on larval populations of Helicoverpa armigera in chickpea crop ecosystems.

    PubMed

    Younas, Aneela; Wakil, Waqas; Khan, Zaeema; Shaaban, Muhammad; Prager, Sean Michael

    2017-02-01

    A robust integrated pest management (IPM) programme is needed to reduce the use of insecticides in controlling Helicoverpa armigera. Therefore, a 2 year field study was conducted to evaluate the use of alternative control measures (biochemical use) for H. armigera relative to exclusively using chemical insecticides. The entomopathogenic fungus Beauveria bassiana, jasmonic acid and the insecticide chlorantraniliprole were each applied twice during the chickpea growing season. All three applied materials (either alone or combined) significantly (P ≤ 0.05) reduced the larval population of H. armigera and pod infestation. Effects increased with time, and the maximum difference was observed 7 days after the second application in each year. The lowest numbers of larvae per plant and pod infestation were in the B. bassiana 3.21 × 10(6) + chlorantraniliprole treatment in both 2009/2010 and 2010/2011 year. The reduction in the larval population and pod infestation increased chickpea yield and the highest yield in both seasons, and the maximum yield was obtained in the B. bassiana 3.21 × 10(6) + chlorantraniliprole treatment. The populations of natural enemies were highest in the jasmonic acid treatment. The results suggest that B. bassiana, jasmonic acid and chlorantraniliprole may be useful components for the H. armigera IPM strategy. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. miR-200 family controls late steps of postnatal forebrain neurogenesis via Zeb2 inhibition

    PubMed Central

    Beclin, Christophe; Follert, Philipp; Stappers, Elke; Barral, Serena; Nathalie, Coré; de Chevigny, Antoine; Magnone, Virginie; Lebrigand, Kévin; Bissels, Ute; Huylebroeck, Danny; Bosio, Andreas; Barbry, Pascal; Seuntjens, Eve; Cremer, Harold

    2016-01-01

    During neurogenesis, generation, migration and integration of the correct numbers of each neuron sub-type depends on complex molecular interactions in space and time. MicroRNAs represent a key control level allowing the flexibility and stability needed for this process. Insight into the role of this regulatory pathway in the brain is still limited. We performed a sequential experimental approach using postnatal olfactory bulb neurogenesis in mice, starting from global expression analyses to the investigation of functional interactions between defined microRNAs and their targets. Deep sequencing of small RNAs extracted from defined compartments of the postnatal neurogenic system demonstrated that the miR-200 family is specifically induced during late neuronal differentiation stages. Using in vivo strategies we interfered with the entire miR-200 family in loss- and gain-of-function settings, showing a role of miR-200 in neuronal maturation. This function is mediated by targeting the transcription factor Zeb2. Interestingly, so far functional interaction between miR-200 and Zeb2 has been exclusively reported in cancer or cultured stem cells. Our data demonstrate that this regulatory interaction is also active during normal neurogenesis. PMID:27767083

  7. Optically stimulated luminescence age controls on late Pleistocene and Holocene coastal lithosomes, North Carolina, USA

    USGS Publications Warehouse

    Mallinson, D.; Burdette, K.; Mahan, S.; Brook, G.

    2008-01-01

    Luminescence ages from a variety of coastal features on the North Carolina Coastal Plain provide age control for shoreline formation and relative sea-level position during the late Pleistocene. A series of paleoshoreline ridges, dating to Marine Isotope Stage (MIS) 5a and MIS 3 have been defined. The Kitty Hawk beach ridges, on the modern Outer Banks, yield ages of 3 to 2??ka. Oxygen-isotope data are used to place these deposits in the context of global climate and sea-level change. The occurrence of MIS 5a and MIS 3 shorelines suggests that glacio-isostatic adjustment (GIA) of the study area is large (ca. 22 to 26??m), as suggested and modeled by other workers, and/or MIS 3 sea level was briefly higher than suggested by some coral reef studies. Correcting the shoreline elevations for GIA brings their elevation in line with other sea-level indicators. The age of the Kitty Hawk beach ridges places the Holocene shoreline well west of its present location at ca. 3 to 2??ka. The age of shoreline progradation is consistent with the ages of other beach ridge complexes in the southeast USA, suggesting some regionally contemporaneous forcing mechanism. ?? 2007 University of Washington.

  8. Controls on high order cyclicity in Late Carnian evaporites in Israel

    NASA Astrophysics Data System (ADS)

    Mordecai Bialik, Or; Korngreen, Dorit; Benjamini, Chaim

    2010-05-01

    The early Mesozoic world was warm, dry and unglaciated, but there is evidence that Milankovitch-order cycles exert control on the sedimentary pattern in the Middle and Late Triassic. The Mohilla Formation at the Ramon outcrop of central Israel is of Tuvalian (upper Carnian) age, and contains a carbonate-evaporite-clastic section demonstrating rapid transitions between lithologies and facies at several scales. The high sensitivity of evaporitic sedimentation to changes in precipitation, humidity, and marine input suggests that cyclic behavior observed in the field at high resolution can be attributed to quantitative and qualitative changes in local environmental factors controlled by a cyclic mechanism. We interpreted cycles form field data both by classic analysis of changes in facies and by spectral analysis using FFT to determine wavelength of cycles in terms of thickness and hierarchy. By calculation of applicable rates of sedimentation per lithology, and introducing a decompaction term, the time frame for these phenomena was established, and the temporal resolution of several orders of cyclicity could be resolved. Direct interpretation of relative sea level change derived from boundary criteria yielded 3 orders of cycles with average wavelength calculated at 23 Kyr, 85 Kyr and 245 Kyr. Spectral analysis of changes of all lithofacies components yielded 6 orders, with groups of wavelengths falling at 20 Kyr (±5), 30 Kyr (±3), 40 Kyr (±1), 60 Kyr (±4), 160 Kyr (one peak), and under 10 Kyr, that may be unresolvable noise. The 20 Kyr , 40 Kyr , 85 Kyr and probably the 160 Kyr and 245 Kyr cycles are consistent with Milankovitch cycle bands and their resonance. Orbital control on the sedimentary pattern would be indicated, and have been described in the Dolomites (Italy). Evaporitic systems of the Triassic have not been interpreted this way, but orbital control on precipitation would have a strong effect that could be tracked by stable isotopes; initial data

  9. Arabidopsis MYC Transcription Factors Are the Target of Hormonal Salicylic Acid/Jasmonic Acid Cross Talk in Response to Pieris brassicae Egg Extract.

    PubMed

    Schmiesing, André; Emonet, Aurélia; Gouhier-Darimont, Caroline; Reymond, Philippe

    2016-04-01

    Arabidopsis (Arabidopsis thaliana) plants recognize insect eggs and activate the salicylic acid (SA) pathway. As a consequence, expression of defense genes regulated by the jasmonic acid (JA) pathway is suppressed and larval performance is enhanced. Cross talk between defense signaling pathways is common in plant-pathogen interactions, but the molecular mechanism mediating this phenomenon is poorly understood. Here, we demonstrate that egg-induced SA/JA antagonism works independently of the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ORA59, which controls the ERF branch of the JA pathway. In addition, treatment with egg extract did not enhance expression or stability of JASMONATE ZIM-domain transcriptional repressors, and SA/JA cross talk did not involve JASMONATE ASSOCIATED MYC2-LIKEs, which are negative regulators of the JA pathway. Investigating the stability of MYC2, MYC3, and MYC4, three basic helix-loop-helix transcription factors that additively control jasmonate-related defense responses, we found that egg extract treatment strongly diminished MYC protein levels in an SA-dependent manner. Furthermore, we identified WRKY75 as a novel and essential factor controlling SA/JA cross talk. These data indicate that insect eggs target the MYC branch of the JA pathway and uncover an unexpected modulation of SA/JA antagonism depending on the biological context in which the SA pathway is activated. © 2016 American Society of Plant Biologists. All Rights Reserved.

  10. Arabidopsis MYC Transcription Factors Are the Target of Hormonal Salicylic Acid/Jasmonic Acid Cross Talk in Response to Pieris brassicae Egg Extract1[OPEN

    PubMed Central

    Schmiesing, André; Gouhier-Darimont, Caroline

    2016-01-01

    Arabidopsis (Arabidopsis thaliana) plants recognize insect eggs and activate the salicylic acid (SA) pathway. As a consequence, expression of defense genes regulated by the jasmonic acid (JA) pathway is suppressed and larval performance is enhanced. Cross talk between defense signaling pathways is common in plant-pathogen interactions, but the molecular mechanism mediating this phenomenon is poorly understood. Here, we demonstrate that egg-induced SA/JA antagonism works independently of the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ORA59, which controls the ERF branch of the JA pathway. In addition, treatment with egg extract did not enhance expression or stability of JASMONATE ZIM-domain transcriptional repressors, and SA/JA cross talk did not involve JASMONATE ASSOCIATED MYC2-LIKEs, which are negative regulators of the JA pathway. Investigating the stability of MYC2, MYC3, and MYC4, three basic helix-loop-helix transcription factors that additively control jasmonate-related defense responses, we found that egg extract treatment strongly diminished MYC protein levels in an SA-dependent manner. Furthermore, we identified WRKY75 as a novel and essential factor controlling SA/JA cross talk. These data indicate that insect eggs target the MYC branch of the JA pathway and uncover an unexpected modulation of SA/JA antagonism depending on the biological context in which the SA pathway is activated. PMID:26884488

  11. Diagnostic Tests to Support Late-Stage Control Programs for Schistosomiasis and Soil-Transmitted Helminthiases

    PubMed Central

    Cantera, Jason L.; Storey, Helen L.; Leader, Brandon T.; de los Santos, Tala

    2016-01-01

    Global efforts to address schistosomiasis and soil-transmitted helminthiases (STH) include deworming programs for school-aged children that are made possible by large-scale drug donations. Decisions on these mass drug administration (MDA) programs currently rely on microscopic examination of clinical specimens to determine the presence of parasite eggs. However, microscopy-based methods are not sensitive to the low-intensity infections that characterize populations that have undergone MDA. Thus, there has been increasing recognition within the schistosomiasis and STH communities of the need for improved diagnostic tools to support late-stage control program decisions, such as when to stop or reduce MDA. Failure to adequately address the need for new diagnostics could jeopardize achievement of the 2020 London Declaration goals. In this report, we assess diagnostic needs and landscape potential solutions and determine appropriate strategies to improve diagnostic testing to support control and elimination programs. Based upon literature reviews and previous input from experts in the schistosomiasis and STH communities, we prioritized two diagnostic use cases for further exploration: to inform MDA-stopping decisions and post-MDA surveillance. To this end, PATH has refined target product profiles (TPPs) for schistosomiasis and STH diagnostics that are applicable to these use cases. We evaluated the limitations of current diagnostic methods with regards to these use cases and identified candidate biomarkers and diagnostics with potential application as new tools. Based on this analysis, there is a need to develop antigen-detecting rapid diagnostic tests (RDTs) with simplified, field-deployable sample preparation for schistosomiasis. Additionally, there is a need for diagnostic tests that are more sensitive than the current methods for STH, which may include either a field-deployable molecular test or a simple, low-cost, rapid antigen-detecting test. PMID:28005900

  12. Controls on the Burial of Organic Carbon in the Late Mississippian Craven Basin, UK

    NASA Astrophysics Data System (ADS)

    Emmings, Joseph; Davies, Sarah; Stephenson, Mike; Vane, Chris; Leng, Melanie

    2016-04-01

    A key question for understanding the long term geological carbon cycle is what controls the distribution, abundance and type of organic matter (OM) that is preserved in the deep-water basin sink? The Bowland Shale (Late Mississippian) was deposited in a relatively deep water setting as part of an epicontinental seaway that extended from western Europe to the Lublin Basin, Poland and may therefore present a significant sink for organic carbon. There are few legacy boreholes with core through the Bowland Shale Formation to address this question; however, exposures across Lancashire and Yorkshire provide excellent spatial coverage. Data from these sites will ultimately provide insights into the controls (sedimentological, biological, geochemical) on the spatial distribution of OM in approximately time-equivalent sample locations. In an exposed (124 m thick) succession of the Bowland Shale, located in the Craven Basin, Lancashire, we identify variations in lithology, organic geochemistry (including total organic carbon (TOC), RockEval (RE) and carbon isotope data (δ13C)), palynology and inorganic geochemistry (e.g., major and trace elements). By comparing these data across a suite of outcrop drill cores, we have developed a strategy for sampling fresh material from outcrop to ensure our data are unaffected by modern weathering. At the field-scale, the dominant mudstone lithology is interbedded with decimetre thick, carbonate-cemented silty to fine sandy turbidites that likely represent at least 40 events. Preliminary data indicate fresh (unweathered) mudstone TOC ranges between 4 to 6 wt. % and exhibits exceptionally low oxygen index (OI; typically < 10), low to moderate hydrogen index (HI; 150) and Tmax at 430°C. Palynological and δ13C results corroborate the RE data, which indicate a dominance of (marine) amorphous organic matter. A range of sedimentary and water column processes, identified through interpretation of sedimentological and inorganic geochemical data

  13. Purification in an active form of the phage phi 29 protein p4 that controls the viral late transcription.

    PubMed Central

    Barthelemy, I; Lázaro, J M; Méndez, E; Mellado, R P; Salas, M

    1987-01-01

    The phage phi 29 protein p4, that controls viral late transcription, was highly purified from Escherichia coli cells harbouring a gene 4-containing plasmid. This protein, representing about 6% of the total cellular protein, was obtained in a highly purified form. The protein was characterized as p4 by amino acid analysis and NH2-terminal sequence determination. The purified protein was active in an in vitro transcription assay, allowing specific initiation of transcription at the phi 29 A3 late promoter in the presence of Bacillus subtilis sigma 43-RNA polymerase holoenzyme. Images PMID:3671066

  14. Late - Cycle Injection of Air/Oxygen - Enriched Air for Diesel Exhaust Emissions Control

    SciTech Connect

    Mather, Daniel

    2000-08-20

    Reduce the ''Engine Out'' particulates using the ''In Cylinder'' technique of late cycle auxiliary gas injection (AGI). Reduce the ''Engine Out'' NOx by combining AGI with optimization of fuel injection parameters. Maintain or Improve the Fuel Efficiency.

  15. Silverleaf whitefly induces salicylic acid defenses and suppresses effectual jasmonic acid defenses.

    PubMed

    Zarate, Sonia I; Kempema, Louisa A; Walling, Linda L

    2007-02-01

    The basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (Bemisia tabaci type B; SLWF) on Arabidopsis (Arabidopsis thaliana) were investigated. Sentinel defense gene RNAs were monitored in SLWF-infested and control plants. Salicylic acid (SA)-responsive gene transcripts accumulated locally (PR1, BGL2, PR5, SID2, EDS5, PAD4) and systemically (PR1, BGL2, PR5) during SLWF nymph feeding. In contrast, jasmonic acid (JA)- and ethylene-dependent RNAs (PDF1.2, VSP1, HEL, THI2.1, FAD3, ERS1, ERF1) were repressed or not modulated in SLWF-infested leaves. To test for a role of SA and JA pathways in basal defense, SLWF development on mutant and transgenic lines that constitutively activate or impair defense pathways was determined. By monitoring the percentage of SLWF nymphs in each instar, we show that mutants that activate SA defenses (cim10) or impair JA defenses (coi1) accelerated SLWF nymphal development. Reciprocally, mutants that activate JA defenses (cev1) or impair SA defenses (npr1, NahG) slowed SLWF nymphal development. Furthermore, when npr1 plants, which do not activate downstream SA defenses, were treated with methyl jasmonate, a dramatic delay in nymph development was observed. Collectively, these results showed that SLWF-repressed, JA-regulated defenses were associated with basal defense to the SLWF.

  16. Wound-Inducible Proteinase Inhibitors in Pepper. Differential Regulation upon Wounding, Systemin, and Methyl Jasmonate1

    PubMed Central

    Moura, Daniel S.; Ryan, Clarence A.

    2001-01-01

    Seven small (approximately 6,000 D) wound-inducible proteinase inhibitor proteins were isolated from leaves of pepper (Capsicum annuum) plants that are members of the potato inhibitor II family. N-terminal sequences obtained indicated that the pepper leaf proteinase inhibitors (PLPIs) exhibit homology to two GenBank accessions that code for preproteins containing three isoinhibitors domains each that, when post-translationally processed, can account for the mixture of isoinhibitors that are reported herein from pepper leaves. A constitutive level of PLPI proteins was found in pepper leaves, and these levels increased up to 2.6-fold upon wounding of the lower leaves. Exposing intact plants to methyl jasmonate vapors induced the accumulation of PLPIs. Supplying excised young pepper plants with water through the cut stems induced PLPI proteins to levels higher than those found in intact plants, but with high variability. Supplying the excised plants with systemin did not result in an increase of PLPI levels that were statistically higher than levels found in excised plants. Gel-blot analyses of PLPI induction revealed the presence of two mRNA bands, having slightly different mobilities in agarose gels. Only the low Mr mRNA is present in untreated control plants, and it appears to be responsible for the constitutive levels of PLPI found in leaves. Both mRNA species are wound- and methyl jasmonate-inducible. Only the low- Mr species is weakly induced by systemin, indicating a differential expression of the two PLPI species. PMID:11351092

  17. Transcriptome profiling revealed novel transcriptional regulators in maize responses to Ostrinia furnacalis and jasmonic acid

    PubMed Central

    Teng, Shouzhen; Liang, Haisheng; Xin, Hongjia; Gao, Hongjiang; Huang, Dafang

    2017-01-01

    Chewing insects cause severe yield losses in crop production worldwide. Crop plants counteract chewing insects by transcriptionally promoting a repertoire of defense gene products that are either toxic to, or attractive to the natural enemies of, pest insects. However, the complexity of the transcriptional reprogramming in plant defense response against chewing insects is still not well understood. In this study, the genome-wide early responses in maize seedlings to Asian corn borer (ACB, Ostrinia furnacalis) and also to jasmonic acid(JA), the pivotal phytohormone controlling plant defense response against herbivory, were transcriptionally profiled by RNA-Seq. Clustering of differentially expressed genes (DEGs) along with functional enrichment analysis revealed important biological processes regulated in response to ACB infestation and/or jasmonic acid. Moreover, DEGs with distinct expression patterns were differentially enriched with diverse families of cis-elements on their promoters. Multiple inventories of differentially expressed transcription factors (DETFs) in each DEG group were also analyzed. A transient expression assay using transfected maize protoplastswas established to examine the potential roles of DETFs in maize defense response and JA signaling, and this was used to show that ZmNAC60, an ACB- and JA-inducible DETF, represented a novel positive regulator of JA and defense pathway genes. This study provided a comprehensive transcriptional picture for the early dynamics of maize defense responses and JA signaling, and the identification of DETFs offered potential targets for further functional genomics investigation of master regulators in maize defense responses against herbivory. PMID:28520800

  18. Transcriptome profiling revealed novel transcriptional regulators in maize responses to Ostrinia furnacalis and jasmonic acid.

    PubMed

    Wang, Hai; Li, Shengyan; Teng, Shouzhen; Liang, Haisheng; Xin, Hongjia; Gao, Hongjiang; Huang, Dafang; Lang, Zhihong

    2017-01-01

    Chewing insects cause severe yield losses in crop production worldwide. Crop plants counteract chewing insects by transcriptionally promoting a repertoire of defense gene products that are either toxic to, or attractive to the natural enemies of, pest insects. However, the complexity of the transcriptional reprogramming in plant defense response against chewing insects is still not well understood. In this study, the genome-wide early responses in maize seedlings to Asian corn borer (ACB, Ostrinia furnacalis) and also to jasmonic acid(JA), the pivotal phytohormone controlling plant defense response against herbivory, were transcriptionally profiled by RNA-Seq. Clustering of differentially expressed genes (DEGs) along with functional enrichment analysis revealed important biological processes regulated in response to ACB infestation and/or jasmonic acid. Moreover, DEGs with distinct expression patterns were differentially enriched with diverse families of cis-elements on their promoters. Multiple inventories of differentially expressed transcription factors (DETFs) in each DEG group were also analyzed. A transient expression assay using transfected maize protoplastswas established to examine the potential roles of DETFs in maize defense response and JA signaling, and this was used to show that ZmNAC60, an ACB- and JA-inducible DETF, represented a novel positive regulator of JA and defense pathway genes. This study provided a comprehensive transcriptional picture for the early dynamics of maize defense responses and JA signaling, and the identification of DETFs offered potential targets for further functional genomics investigation of master regulators in maize defense responses against herbivory.

  19. Jasmonates induce both defense responses and communication in monocotyledonous and dicotyledonous plants.

    PubMed

    Okada, Kazunori; Abe, Hiroshi; Arimura, Gen-ichiro

    2015-01-01

    Jasmonic acid (JA) and its derivatives (jasmonates, JAs) are phytohormones with essential roles in plant defense against pathogenesis and herbivorous arthropods. Both the up- and down-regulation of defense responses are dependent on signaling pathways mediated by JAs as well as other stress hormones (e.g. salicylic acid), generally those involving the transcriptional and post-transcriptional regulation of transcription factors via protein modification and epigenetic regulation. In addition to the typical model plant Arabidopsis (a dicotyledon), advances in genetics research have made rice a model monocot in which innovative pest control traits can be introduced and whose JA signaling pathway can be studied. In this review, we introduce the dynamic functions of JAs in plant defense strategy using defensive substances (e.g. indole alkaloids and terpenoid phytoalexins) and airborne signals (e.g. green leaf volatiles and volatile terpenes) in response to biotrophic and necrotrophic pathogens as well as above-ground and below-ground herbivores. We then discuss the important issue of how the mutualism of herbivorous arthropods with viruses or bacteria can cause cross-talk between JA and other phytohormones to counter the defense systems. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Bioassays for assessing jasmonate-dependent defenses triggered by pathogens, herbivorous insects, or beneficial rhizobacteria.

    PubMed

    Van Wees, Saskia C M; Van Pelt, Johan A; Bakker, Peter A H M; Pieterse, Corné M J

    2013-01-01

    Jasmonates, together with other plant hormones, are important orchestrators of the plant immune system. The different hormone-controlled signaling pathways cross-communicate in an antagonistic or a synergistic manner, providing the plant with a powerful capacity to finely regulate its immune response. Jasmonic acid (JA) signaling is required for plant resistance to harmful organisms, such as necrotrophic pathogens and herbivorous insects. Furthermore, JA signaling is essential in interactions of plants with beneficial microbes that induce systemic resistance to pathogens and insects. The role of JA signaling components in plant immunity can be studied by performing bioassays with different interacting organisms. Determination of the level of resistance and the induction of defense responses in plants with altered JA components, through mutation or ectopic expression, will unveil novel mechanisms of JA signaling. We provide detailed protocols of bioassays with the model plant Arabidopsis thaliana challenged with the pathogens Botrytis cinerea and Pseudomonas syringae, the insect herbivore Pieris rapae, and the beneficial microbe Pseudomonas fluorescens. In addition, we describe pharmacological assays to study the modulation of JA-regulated responses by exogenous application of combinations of hormones, because a simultaneous rise in hormone levels occurs during interaction of plants with other organisms.

  1. Silverleaf Whitefly Induces Salicylic Acid Defenses and Suppresses Effectual Jasmonic Acid Defenses1[W][OA

    PubMed Central

    Zarate, Sonia I.; Kempema, Louisa A.; Walling, Linda L.

    2007-01-01

    The basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (Bemisia tabaci type B; SLWF) on Arabidopsis (Arabidopsis thaliana) were investigated. Sentinel defense gene RNAs were monitored in SLWF-infested and control plants. Salicylic acid (SA)-responsive gene transcripts accumulated locally (PR1, BGL2, PR5, SID2, EDS5, PAD4) and systemically (PR1, BGL2, PR5) during SLWF nymph feeding. In contrast, jasmonic acid (JA)- and ethylene-dependent RNAs (PDF1.2, VSP1, HEL, THI2.1, FAD3, ERS1, ERF1) were repressed or not modulated in SLWF-infested leaves. To test for a role of SA and JA pathways in basal defense, SLWF development on mutant and transgenic lines that constitutively activate or impair defense pathways was determined. By monitoring the percentage of SLWF nymphs in each instar, we show that mutants that activate SA defenses (cim10) or impair JA defenses (coi1) accelerated SLWF nymphal development. Reciprocally, mutants that activate JA defenses (cev1) or impair SA defenses (npr1, NahG) slowed SLWF nymphal development. Furthermore, when npr1 plants, which do not activate downstream SA defenses, were treated with methyl jasmonate, a dramatic delay in nymph development was observed. Collectively, these results showed that SLWF-repressed, JA-regulated defenses were associated with basal defense to the SLWF. PMID:17189328

  2. Attenuation of the jasmonate burst, plant defensive traits, and resistance to specialist monarch caterpillars on shaded common milkweed (Asclepias syriaca).

    PubMed

    Agrawal, Anurag A; Kearney, Emily E; Hastings, Amy P; Ramsey, Trey E

    2012-07-01

    Plant responses to herbivory and light competition are often in opposing directions, posing a potential conflict for plants experiencing both stresses. For sun-adapted species, growing in shade typically makes plants more constitutively susceptible to herbivores via reduced structural and chemical resistance traits. Nonetheless, the impact of light environment on induced resistance has been less well-studied, especially in field experiments that link physiological mechanisms to ecological outcomes. Accordingly, we studied induced resistance of common milkweed (Asclepias syriaca, a sun-adapted plant), and linked hormonal responses, resistance traits, and performance of specialist monarch caterpillars (Danaus plexippus) in varying light environments. In natural populations, plants growing under forest-edge shade showed reduced levels of resistance traits (lower leaf toughness, cardenolides, and trichomes) and enhanced light-capture traits (higher specific leaf area, larger leaves, and lower carbon-to-nitrogen ratio) compared to paired plants in full sun. In a field experiment repeated over two years, only milkweeds growing in full sun exhibited induced resistance to monarchs, whereas plants growing in shade were constitutively more susceptible and did not induce resistance. In a more controlled field experiment, plant hormones were higher in the sun (jasmonic acid, salicylic acid, abscisic acid, indole acidic acid) and were induced by herbivory (jasmonic acid and abscisic acid). In particular, the jasmonate burst following herbivory was halved in plants raised in shaded habitats, and this correspondingly reduced latex induction (but not cardenolide induction). Thus, we provide a mechanistic basis for the attenuation of induced plant resistance in low resource environments. Additionally, there appears to be specificity in these interactions, with light-mediated impacts on jasmonate-induction being stronger for latex exudation than cardenolides.

  3. Higher education is an age-independent predictor of white matter integrity and cognitive control in late adolescence.

    PubMed

    Noble, Kimberly G; Korgaonkar, Mayuresh S; Grieve, Stuart M; Brickman, Adam M

    2013-09-01

    Socioeconomic status is an important predictor of cognitive development and academic achievement. Late adolescence provides a unique opportunity to study how the attainment of socioeconomic status (in the form of years of education) relates to cognitive and neural development, during a time when age-related cognitive and neural development is ongoing. During late adolescence it is possible to disambiguate age- and education-related effects on the development of these processes. Here we assessed the degree to which higher educational attainment was related to performance on a cognitive control task, controlling for age. We then used diffusion tensor imaging (DTI) to assess the degree to which white matter microstructure might mediate this relationship. When covarying age, significant associations were found between educational attainment and fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF) and cingulum bundle (CB). Further, when covarying age, FA in these regions was associated with cognitive control. Finally, mediation analyses revealed that the age-independent association between educational attainment and cognitive control was completely accounted for by FA in these regions. The uncinate fasciculus, a late-myelinated control region not implicated in cognitive control, did not mediate this effect.

  4. Acyl-CoA N-acyltransferase influences fertility by regulating lipid metabolism and jasmonic acid biogenesis in cotton

    PubMed Central

    Fu, Wenfeng; Shen, Ying; Hao, Juan; Wu, Jianyong; Ke, Liping; Wu, Caiyun; Huang, Kai; Luo, Binglun; Xu, Mingfeng; Cheng, Xiaofei; Zhou, Xueping; Sun, Jie; Xing, Chaozhu; Sun, Yuqiang

    2015-01-01

    Cotton (Gossypium spp.) is an important economic crop and there is obvious heterosis in cotton, fertility has played an important role in this heterosis. However, the genes that exhibit critical roles in anther development and fertility are not well understood. Here, we report an acyl-CoA N-acyltransferase (EC2.3; GhACNAT) that plays a key role in anther development and fertility. Suppression of GhACNAT by virus-induced gene silencing in transgenic cotton (G. hirsutum L. cv. C312) resulted in indehiscent anthers that were full of pollen, diminished filaments and stamens, and plant sterility. We found GhACNAT was involved in lipid metabolism and jasmonic acid (JA) biosynthesis. The genes differentially expressed in GhACNAT-silenced plants and C312 were mainly involved in catalytic activity and transcription regulator activity in lipid metabolism. In GhACNAT-silenced plants, the expression levels of genes involved in lipid metabolism and jasmonic acid biosynthesis were significantly changed, the amount of JA in leaves and reproductive organs was significantly decreased compared with the amounts in C312. Treatments with exogenous methyl jasmonate rescued anther dehiscence and pollen release in GhACNAT-silenced plants and caused self-fertility. The GhACNAT gene may play an important role in controlling cotton fertility by regulating the pathways of lipid synthesis and JA biogenesis. PMID:26134787

  5. Methyl jasmonate inhibition of root growth and induction of a leaf protein are decreased in an Arabidopsis thaliana mutant.

    PubMed Central

    Staswick, P E; Su, W; Howell, S H

    1992-01-01

    Jasmonic acid and its methyl ester, methyl jasmonate (MeJA), are plant signaling molecules that affect plant growth and gene expression. Primary root growth of wild-type Arabidopsis thaliana seedlings was inhibited 50% when seedlings were grown on agar medium containing 0.1 M MeJA. An ethyl methanesulfonate mutant (jar1) with decreased sensitivity to MeJA inhibition of root elongation was isolated and characterized. Genetic data indicated the trait was recessive and controlled by a single Mendelian factor. MeJA-induced polypeptides were detected in Arabidopsis leaves by antiserum to a MeJA-inducible vegetative storage protein from soybean. The induction of these proteins by MeJA in the mutant was at least 4-fold less in jar1 compared to wild type. In contrast, seeds of jar1 plants were more sensitive than wild type to inhibition of germination by abscisic acid. These results suggest that the defect in jar1 affects a general jasmonate response pathway, which may regulate multiple genes in different plant organs. Images PMID:11607311

  6. Short- and long-term changes in sugarbeet (Beta vulgaris L.) gene expression due to postharvest jasmonic acid treatment - Data.

    PubMed

    de Oliveira, Lucilene Silva; Fugate, Karen Klotz; Ferrareze, Jocleita Perruzo; Bolton, Melvin D; Deckard, Edward L; Finger, Fernando L

    2017-04-01

    Jasmonic acid is a natural plant hormone that induces native defense responses in plants. Sugarbeet (Beta vulgaris L.) root unigenes that were differentially expressed 2 and 60 days after a postharvest jasmonic acid treatment are presented. Data include changes in unigene expression relative to water-treated controls, unigene annotations against nonredundant (Nr), Swiss-Prot, Clusters of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) protein databases, and unigene annotations with Gene Ontology (GO) terms. Putative defense unigenes are compiled and annotated against the sugarbeet genome. Differential gene expression data were generated by RNA sequencing. Interpretation of the data is available in the research article, "Jasmonic acid causes short- and long-term alterations to the transcriptome and the expression of defense genes in sugarbeet roots" (K.K. Fugate, L.S. Oliveira, J.P. Ferrareze, M.D. Bolton, E.L. Deckard, F.L. Finger, 2017) [1]. Public dissemination of this dataset will allow further analyses of the data.

  7. Acyl-CoA N-acyltransferase influences fertility by regulating lipid metabolism and jasmonic acid biogenesis in cotton.

    PubMed

    Fu, Wenfeng; Shen, Ying; Hao, Juan; Wu, Jianyong; Ke, Liping; Wu, Caiyun; Huang, Kai; Luo, Binglun; Xu, Mingfeng; Cheng, Xiaofei; Zhou, Xueping; Sun, Jie; Xing, Chaozhu; Sun, Yuqiang

    2015-07-02

    Cotton (Gossypium spp.) is an important economic crop and there is obvious heterosis in cotton, fertility has played an important role in this heterosis. However, the genes that exhibit critical roles in anther development and fertility are not well understood. Here, we report an acyl-CoA N-acyltransferase (EC2.3; GhACNAT) that plays a key role in anther development and fertility. Suppression of GhACNAT by virus-induced gene silencing in transgenic cotton (G. hirsutum L. cv. C312) resulted in indehiscent anthers that were full of pollen, diminished filaments and stamens, and plant sterility. We found GhACNAT was involved in lipid metabolism and jasmonic acid (JA) biosynthesis. The genes differentially expressed in GhACNAT-silenced plants and C312 were mainly involved in catalytic activity and transcription regulator activity in lipid metabolism. In GhACNAT-silenced plants, the expression levels of genes involved in lipid metabolism and jasmonic acid biosynthesis were significantly changed, the amount of JA in leaves and reproductive organs was significantly decreased compared with the amounts in C312. Treatments with exogenous methyl jasmonate rescued anther dehiscence and pollen release in GhACNAT-silenced plants and caused self-fertility. The GhACNAT gene may play an important role in controlling cotton fertility by regulating the pathways of lipid synthesis and JA biogenesis.

  8. [Enhanced production of taxuyunnanine c in cell suspension cultures of Taxus chinensis by methyl jasmonate elicitation and in situ absorption].

    PubMed

    Gao, Mingbo; Zhang, Wei; Yu, Xingju

    2010-02-01

    A bioprocess intensification strategy that combines both elicitation and in situ absorption was developed to improve the production of taxuyunnanine c (Tc) in cell suspension cultures of Taxus chinensis. When 100 micromol/L methyl jasmonate was added as an elicitor on Day 7, the Tc content and yield increased 3.6 and 3.3 times respectively, however the cell growth was reduced by 10%-30%. Significant improvement in Tc yield was observed when an absorbent XAD-7 was added on different time of the culture period. The optimum Tc yield was achieved when 100 g/L XAD-7 was added simultaneously with 100 micromol/L methyl jasmonate on Day 7. The maximum Tc yield of 477.4 mg/L was obtained on Day 21 of the culture, being 6.3-fold of the control and 1.9-fold of the 100 micromol/L methyl jasmonate treatment alone. In the combined treatment, 94% of the Tc produced was secreted outside of the cells and absorbed on XAD-7 absorbents. The results demonstrated that the process strategy combining elicitation and in situ absorption was effective to intensify the Tc biosynthesis via elicitation with the removal of product feedback inhibition via absorption, presenting a great potential in commercial applications.

  9. Chemical and genetic exploration of jasmonate biosynthesis and signaling paths.

    PubMed

    Kombrink, Erich

    2012-11-01

    Jasmonates are lipid-derived compounds that act as signals in plant stress responses and developmental processes. Enzymes participating in biosynthesis of jasmonic acid (JA) and components of JA signaling have been extensively characterized by biochemical and molecular-genetic tools. Mutants have helped to define the pathway for synthesis of jasmonoyl-L-isoleucine (JA-Ile), the bioactive form of JA, and to identify the F-box protein COI1 as central regulatory unit. Details on the molecular mechanism of JA signaling were recently unraveled by the discovery of JAZ proteins that together with the adaptor protein NINJA and the general co-repressor TOPLESS form a transcriptional repressor complex. The current model of JA perception and signaling implies the SCF(COI1) complex operating as E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ proteins for degradation by the 26S proteasome pathway, thereby allowing MYC2 and other transcription factors to activate gene expression. Chemical strategies, as integral part of jasmonate research, have helped the establishment of structure-activity relationships and the discovery of (+)-7-iso-JA-L-Ile as the major bioactive form of the hormone. The transient nature of its accumulation highlights the need to understand catabolism and inactivation of JA-Ile and recent studies indicate that oxidation of JA-Ile by cytochrome P450 monooxygenase is the major mechanism for turning JA signaling off. Plants contain numerous JA metabolites, which may have pronounced and differential bioactivity. A major challenge in the field of plant lipid signaling is to identify the cognate receptors and modes of action of these bioactive jasmonates/oxylipins.

  10. A role for xanthine oxidase in the control of fetal cardiovascular function in late gestation sheep.

    PubMed

    Herrera, E A; Kane, A D; Hansell, J A; Thakor, A S; Allison, B J; Niu, Y; Giussani, D A

    2012-04-15

    Virtually nothing is known about the effects on fetal physiology of xanthine oxidase inhibition. This is despite maternal treatment with the xanthine oxidase inhibitor allopurinol being considered in human complicated pregnancy to protect the infant’s brain from excessive generation of ROS.We investigated the in vivo effects of maternal treatment with allopurinol on fetal cardiovascular function in ovine pregnancy in late gestation. Under anaesthesia, pregnant ewes and their singleton fetus were instrumented with vascular catheters and flow probes around an umbilical and a fetal femoral artery at 118±1 dGA (days of gestational age; termca. 145 days). Five days later, mothers were infused I.V. with either vehicle (n =11) or allopurinol (n =10). Fetal cardiovascular function was stimulated with increasing bolus doses of phenylephrine (PE) following maternal vehicle or allopurinol. The effects of maternal allopurinol on maternal and fetal cardiovascular function were also investigated following fetal NO blockade (n =6) or fetal β1-adrenergic antagonism (n =7). Maternal allopurinol led to significant increases in fetal heart rate, umbilical blood flow and umbilical vascular conductance, effects abolished by fetal β1-adrenergic antagonism but not by fetal NO blockade. Maternal allopurinol impaired fetal α1-adrenergic pressor and femoral vasopressor responses and enhanced the gain of the fetal cardiac baroreflex. These effects of maternal allopurinol were restored to control levels during fetal NO blockade. Maternal treatment with allopurinol induced maternal hypotension, tachycardia and acid–base disturbance. We conclude that maternal treatment with allopurinol alters in vivo maternal, umbilical and fetal vascular function via mechanisms involving NO and β1-adrenergic stimulation. The evidence suggests that the use of allopurinol in clinical practice should be approached with caution.

  11. Learned control over spinal nociception reduces supraspinal nociception as quantified by late somatosensory evoked potentials.

    PubMed

    Ruscheweyh, Ruth; Bäumler, Maximilian; Feller, Moritz; Krafft, Stefanie; Sommer, Jens; Straube, Andreas

    2015-12-01

    We have recently shown that subjects can learn to use cognitive-emotional strategies to suppress their spinal nociceptive flexor reflex (RIII reflex) under visual RIII feedback and proposed that this reflects learned activation of descending pain inhibition. Here, we investigated whether learned RIII suppression also affects supraspinal nociception and whether previous relaxation training increases success. Subjects were trained over 3 sessions to reduce their RIII size by self-selected cognitive-emotional strategies. Two groups received true RIII feedback (with or without previous relaxation training) and a sham group received false feedback (15 subjects per group). RIII reflexes, late somatosensory evoked potentials (SEPs), and F-waves were recorded and pain intensity ratings collected. Both true feedback groups achieved significant (P < 0.01) but similar RIII suppression (to 79% ± 21% and 70% ± 17% of control). Somatosensory evoked potential amplitude (100-150 milliseconds after stimulation) was reduced in parallel with the RIII size (r = 0.57, P < 0.01). In the sham group, neither RIII size nor SEP amplitude was significantly reduced during feedback training. Pain intensity was significantly reduced in all 3 groups and also correlated with RIII reduction (r = 0.44, P < 0.01). F-wave parameters were not affected during RIII suppression. The present results show that learned RIII suppression also affects supraspinal nociception as quantified by SEPs, although effects on pain ratings were less clear. Lower motor neuron excitability as quantified by F-waves was not affected. Previous relaxation training did not significantly improve RIII feedback training success.

  12. A role for xanthine oxidase in the control of fetal cardiovascular function in late gestation sheep

    PubMed Central

    Herrera, E A; Kane, A D; Hansell, J A; Thakor, A S; Allison, B J; Niu, Y; Giussani, D A

    2012-01-01

    Virtually nothing is known about the effects on fetal physiology of xanthine oxidase inhibition. This is despite maternal treatment with the xanthine oxidase inhibitor allopurinol being considered in human complicated pregnancy to protect the infant's brain from excessive generation of ROS. We investigated the in vivo effects of maternal treatment with allopurinol on fetal cardiovascular function in ovine pregnancy in late gestation. Under anaesthesia, pregnant ewes and their singleton fetus were instrumented with vascular catheters and flow probes around an umbilical and a fetal femoral artery at 118 ± 1 dGA (days of gestational age; term ca. 145 days). Five days later, mothers were infused i.v. with either vehicle (n= 11) or allopurinol (n= 10). Fetal cardiovascular function was stimulated with increasing bolus doses of phenylephrine (PE) following maternal vehicle or allopurinol. The effects of maternal allopurinol on maternal and fetal cardiovascular function were also investigated following fetal NO blockade (n= 6) or fetal β1-adrenergic antagonism (n= 7). Maternal allopurinol led to significant increases in fetal heart rate, umbilical blood flow and umbilical vascular conductance, effects abolished by fetal β1-adrenergic antagonism but not by fetal NO blockade. Maternal allopurinol impaired fetal α1-adrenergic pressor and femoral vasopressor responses and enhanced the gain of the fetal cardiac baroreflex. These effects of maternal allopurinol were restored to control levels during fetal NO blockade. Maternal treatment with allopurinol induced maternal hypotension, tachycardia and acid–base disturbance. We conclude that maternal treatment with allopurinol alters in vivo maternal, umbilical and fetal vascular function via mechanisms involving NO and β1-adrenergic stimulation. The evidence suggests that the use of allopurinol in clinical practice should be approached with caution. PMID:22331413

  13. An information theory account of late frontoparietal ERP positivities in cognitive control.

    PubMed

    Barceló, Francisco; Cooper, Patrick S

    2017-03-15

    ERP research on task switching has revealed distinct transient and sustained positive waveforms (latency circa 300-900 ms) while shifting task rules or stimulus-response (S-R) mappings. However, it remains unclear whether such switch-related positivities show similar scalp topography and index context-updating mechanisms akin to those posed for domain-general (i.e., classic P300) positivities in many task domains. To examine this question, ERPs were recorded from 31 young adults (18-30 years) while they were intermittently cued to switch or repeat their perceptual categorization of Gabor gratings varying in color and thickness (switch task), or else they performed two visually identical control tasks (go/no-go and oddball). Our task cueing paradigm examined two temporarily distinct stages of proactive rule updating and reactive rule execution. A simple information theory model helped us gauge cognitive demands under distinct temporal and task contexts in terms of low-level S-R pathways and higher-order rule updating operations. Task demands modulated domain-general (indexed by classic oddball P3) and switch positivities-indexed by both a cue-locked late positive complex and a sustained positivity ensuing task transitions. Topographic scalp analyses confirmed subtle yet significant split-second changes in the configuration of neural sources for both domain-general P3s and switch positivities as a function of both the temporal and task context. These findings partly meet predictions from information estimates, and are compatible with a family of P3-like potentials indexing functionally distinct neural operations within a common frontoparietal "multiple demand" system during the preparation and execution of simple task rules. © 2016 Society for Psychophysiological Research.

  14. Jasmonate-dependent depletion of soluble sugars compromises plant resistance to Manduca sexta.

    PubMed

    Machado, Ricardo A R; Arce, Carla C M; Ferrieri, Abigail P; Baldwin, Ian T; Erb, Matthias

    2015-07-01

    Jasmonates regulate plant secondary metabolism and herbivore resistance. How they influence primary metabolites and how this may affect herbivore growth and performance are not well understood. We profiled sugars and starch of jasmonate biosynthesis-deficient and jasmonate-insensitive Nicotiana attenuata plants and manipulated leaf carbohydrates through genetic engineering and in vitro complementation to assess how jasmonate-dependent sugar accumulation affects the growth of Manduca sexta caterpillars. We found that jasmonates reduce the constitutive and herbivore-induced concentration of glucose and fructose in the leaves across different developmental stages. Diurnal, jasmonate-dependent inhibition of invertase activity was identified as a likely mechanism for this phenomenon. Contrary to our expectation, both in planta and in vitro approaches showed that the lower sugar concentrations led to increased M. sexta growth. As a consequence, jasmonate-dependent depletion of sugars rendered N. attenuata plants more susceptible to M. sexta attack. In conclusion, jasmonates are important regulators of leaf carbohydrate accumulation and this determines herbivore growth. Jasmonate-dependent resistance is reduced rather than enhanced through the suppression of glucose and fructose concentrations, which may contribute to the evolution of divergent resistance strategies of plants in nature.

  15. Enhancement of phytosterols, taraxasterol and induction of extracellular pathogenesis-related proteins in cell cultures of Solanum lycopersicum cv Micro-Tom elicited with cyclodextrins and methyl jasmonate.

    PubMed

    Briceño, Zuleika; Almagro, Lorena; Sabater-Jara, Ana B; Calderón, Antonio A; Pedreño, María Angeles; Ferrer, María Angeles

    2012-07-15

    Suspension-cultured cells of Solanum lycopersicum cv Micro-Tom were used to evaluate the effect of methyl jasmonate and cyclodextrins, separately or in combination, on the induction of defense responses. An extracellular accumulation of two sterols (isofucosterol and β-sitosterol) and taraxasterol, a common tomato fruit cuticular triterpene, were observed. Their levels were higher in Micro-Tom tomato suspension cultured cells elicited with cyclodextrins than in control and methyl jasmonate-treated cells. Also, their accumulation profiles during the cell growth phase were markedly different. The most striking feature in response to cyclodextrin treatments was the observed enhancement of taraxasterol accumulation. Likewise, the exogenous application of methyl jasmonate and cyclodextrins induced the accumulation of pathogenesis-related proteins. Analysis of the extracellular proteome showed the presence of amino acid sequences homologous to pathogenesis-related 1 and 5 proteins, a cationic peroxidase and a biotic cell death-associated protein, which suggests that methyl jasmonate and cyclodextrins could play a role in mediating defense-related gene product expression in S. lycopersicum cv Micro-Tom. Copyright © 2012 Elsevier GmbH. All rights reserved.

  16. Modeling the Climatic Controls and Topographic Form of Modern and Late Pleistocene Tropical Peruvian Glaciers

    NASA Astrophysics Data System (ADS)

    Mark, B. G.; Stansell, N.; Fairman, J. G.; Plummer, M. A.; Rodbell, D. T.

    2010-12-01

    Glaciers in the tropical highlands are important and highly sensitive indicators of global climate change over different time scales. Simulating glacier extent from basic climatic and topographic input elucidates understanding of present glacier-climate processes, climate control over past glacial extent, and future impacts of changing climate. We apply a physically based, 2-D, glacier model to reconstruct steady-state glacier forms and mass distributions for a range of tropical climatic conditions in the Cordillera Blanca, Peru (8-10°S). The model is based on gridded digital elevation data, computes the effects of topography on the largest component of surface energy balance, shortwave solar insolation, calculates 2-D, in the horizontal-plane, distribution of snow accumulation using a surface mass and energy balance approach, and reconstructs resultant glacier shape with a 2-D flow model. We are able to reconstruct modern glacier extent to match satellite imagery using climate data assimilated from over 30 Andean stations located between 9-11°S, including current observations at glacier elevations, and compute a modern equilibrium line at ˜5000 m asl. We then apply the model in an inverse approach to infer paleoclimate conditions for late Pleistocene moraine positions mapped in specific valleys with global positioning system positions and dated by radiocarbon dates on lake and peat sediments. Simulations confirm that with no precipitation changes, a cooling of 4.5°C is required to achieve equilibrium glacier shapes terminating at moraine positions bounding Laguna Queshque (4300 m asl 9°50'S; 77°25'W). Alternatively, increasing precipitation by 1.5 times the modern values requires a temperature reduction of 3.75°C for the model to reach the same ELA position. A model sensitivity analysis highlights the importance of both moisture availability and temperature changes in driving tropical Andean glacier fluctuations. Results also indicate that temperature

  17. Multicenter randomized controlled trial comparing early versus late aquatic therapy after total hip or knee arthroplasty.

    PubMed

    Liebs, Thoralf R; Herzberg, Wolfgang; Rüther, Wolfgang; Haasters, Jörg; Russlies, Martin; Hassenpflug, Joachim

    2012-02-01

    To evaluate if the timing of aquatic therapy influences clinical outcomes after total knee arthroplasty (TKA) or total hip arthroplasty (THA). Multicenter randomized controlled trial with 3-, 6-, 12-, and 24-month follow-up. Two university hospitals, 1 municipal hospital, and 1 rural hospital. Patients (N=465) undergoing primary THA (n=280) or TKA (n=185): 156 men, 309 women. Patients were randomly assigned to receive aquatic therapy (pool exercises aimed at training of proprioception, coordination, and strengthening) after 6 versus 14 days after THA or TKA. Primary outcome was self-reported physical function as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 3-, 6-, 12-, and 24-months postoperatively. Results were compared with published thresholds for minimal clinically important improvements. Secondary outcomes included the Medical Outcomes Study 36-Item Short-Form Health Survey, Lequesne-Hip/Knee-Score, WOMAC-pain and stiffness scores, and patient satisfaction. Baseline characteristics of the 2 groups were similar. Analyzing the total study population did not result in statistically significant differences at all follow-ups. However, when performing subanalysis for THA and TKA, opposite effects of early aquatic therapy were seen between TKA and THA. After TKA all WOMAC subscales were superior in the early aquatic therapy group, with effect sizes of WOMAC physical function ranging from .22 to .39. After THA, however, all outcomes were superior in the late aquatic therapy group, with WOMAC effect sizes ranging from .01 to .19. However, the differences between treatment groups of these subanalyses were not statistically significant. Early start of aquatic therapy had contrary effects after TKA when compared with THA and it influenced clinical outcomes after TKA. Although the treatment differences did not achieve statistically significance, the effect size for early aquatic therapy after TKA had the same magnitude as the

  18. Late umbilical cord clamping, neonatal hematocrit and Apgar scores: a randomized controlled trial.

    PubMed

    Salari, Z; Rezapour, M; Khalili, N

    2014-01-01

    Based on current evidence, there is a little agreement on the best timing for after birth umbilical cord clamping. This study was designed to compare the impact of using two different times for cord clamping on hematocrit concentration and Apgar scores of the neonate. Fifty-six healthy full-term vaginally born neonates were allocated to early (10 seconds after delivery) and late (3 minutes after delivery) umbilical cord clamping groups in this randomized clinical trial. We recorded the length of the 3rd stage of labor and Apgar score at 5 minutes. Infant's hematocrit was measured at 2 and 18 hours of age. Neonatal hematocrit differed between the two groups. Late cord clamping group had greater hematocrit at 2 hours (45.5 ± 4 vs. 49.5 ± 4.4, P = 0.0003) and 18 hours (47.7 ± 5.5 vs. 52.9 ± 4.3, P = 0.0002). Apgar scores at 5 minutes (9.3 ± 0.6 vs. 9.4 ± 0.6, p = 0.5) and duration of delivery 3rd stage (10.2 ± 3.7 min vs. 8.9 ± 5 min, P = 0.2) did not differ between early and late cord clamping groups respectively. Late cord clamping leads to a significant increase in the hematocrit of the neonate but it does not have effects on Apgar score and duration of the 3rd stage of labor.

  19. Relationships among Social Support, Perceived Control, and Psychological Distress in Late Life

    ERIC Educational Resources Information Center

    Nemeroff, Robin; Midlarsky, Elizabeth; Meyer, Joseph F.

    2010-01-01

    Social support has been shown to buffer the relationship between life stress and psychological distress in late life. However, little attention has been paid to personality variables that are associated with the capacity to effectively utilize social support. Although the buffering effects of social support were replicated in our sample of 134…

  20. Sequence stratigraphy and depositional controls in late Proterozoic-early Cambrian sediments of Amadeus basin, central Australia

    SciTech Connect

    Lindsay, J.F.

    1987-11-01

    The Amadeus basin is an isolated intracratonic basin at the center of the Australian continent which, because of its location and geometry, provides an ideal opportunity to investigate depositional controls. To this end, more than 6000 km of seismic data, in conjunction with a field and well-log program, have been used in a study of the late Proterozoic-Early Cambrian Arumbera Sandstone. 17 figures.

  1. New roles for cis-jasmone as an insect semiochemical and in plant defense

    PubMed Central

    Birkett, Michael A.; Campbell, Colin A. M.; Chamberlain, Keith; Guerrieri, Emilio; Hick, Alastair J.; Martin, Janet L.; Matthes, Michaela; Napier, Johnathan A.; Pettersson, Jan; Pickett, John A.; Poppy, Guy M.; Pow, Eleanor M.; Pye, Barry J.; Smart, Lesley E.; Wadhams, George H.; Wadhams, Lester J.; Woodcock, Christine M.

    2000-01-01

    cis-Jasmone, or (Z)-jasmone, is well known as a component of plant volatiles, and its release can be induced by damage, for example during insect herbivory. Using the olfactory system of the lettuce aphid to investigate volatiles from plants avoided by this insect, (Z)-jasmone was found to be electrophysiologically active and also to be repellent in laboratory choice tests. In field studies, repellency from traps was demonstrated for the damson-hop aphid, and with cereal aphids numbers were reduced in plots of winter wheat treated with (Z)-jasmone. In contrast, attractant activity was found in laboratory and wind tunnel tests for insects acting antagonistically to aphids, namely the seven-spot ladybird and an aphid parasitoid. When applied in the vapor phase to intact bean plants, (Z)-jasmone induced the production of volatile compounds, including the monoterpene (E)-β-ocimene, which affect plant defense, for example by stimulating the activity of parasitic insects. These plants were more attractive to the aphid parasitoid in the wind tunnel when tested 48 h after exposure to (Z)-jasmone had ceased. This possible signaling role of (Z)-jasmone is qualitatively different from that of the biosynthetically related methyl jasmonate and gives a long-lasting effect after removal of the stimulus. Differential display was used to compare mRNA populations in bean leaves exposed to the vapor of (Z)-jasmone and methyl jasmonate. One differentially displayed fragment was cloned and shown by Northern blotting to be up-regulated in leaf tissue by (Z)-jasmone. This sequence was identified by homology as being derived from a gene encoding an α-tubulin isoform. PMID:10900270

  2. New roles for cis-jasmone as an insect semiochemical and in plant defense.

    PubMed

    Birkett, M A; Campbell, C A; Chamberlain, K; Guerrieri, E; Hick, A J; Martin, J L; Matthes, M; Napier, J A; Pettersson, J; Pickett, J A; Poppy, G M; Pow, E M; Pye, B J; Smart, L E; Wadhams, G H; Wadhams, L J; Woodcock, C M

    2000-08-01

    cis-jasmone, or (Z)-jasmone, is well known as a component of plant volatiles, and its release can be induced by damage, for example during insect herbivory. Using the olfactory system of the lettuce aphid to investigate volatiles from plants avoided by this insect, (Z)-jasmone was found to be electrophysiologically active and also to be repellent in laboratory choice tests. In field studies, repellency from traps was demonstrated for the damson-hop aphid, and with cereal aphids numbers were reduced in plots of winter wheat treated with (Z)-jasmone. In contrast, attractant activity was found in laboratory and wind tunnel tests for insects acting antagonistically to aphids, namely the seven-spot ladybird and an aphid parasitoid. When applied in the vapor phase to intact bean plants, (Z)-jasmone induced the production of volatile compounds, including the monoterpene (E)-beta-ocimene, which affect plant defense, for example by stimulating the activity of parasitic insects. These plants were more attractive to the aphid parasitoid in the wind tunnel when tested 48 h after exposure to (Z)-jasmone had ceased. This possible signaling role of (Z)-jasmone is qualitatively different from that of the biosynthetically related methyl jasmonate and gives a long-lasting effect after removal of the stimulus. Differential display was used to compare mRNA populations in bean leaves exposed to the vapor of (Z)-jasmone and methyl jasmonate. One differentially displayed fragment was cloned and shown by Northern blotting to be up-regulated in leaf tissue by (Z)-jasmone. This sequence was identified by homology as being derived from a gene encoding an alpha-tubulin isoform.

  3. Jasmonates induce nonapoptotic death in high-resistance mutant p53-expressing B-lymphoma cells

    PubMed Central

    Fingrut, Orit; Reischer, Dorit; Rotem, Ronit; Goldin, Natalia; Altboum, Irit; Zan-Bar, Israel; Flescher, Eliezer

    2005-01-01

    Mutations in p53, a tumor suppressor gene, occur in more than half of human cancers. Therefore, we tested the hypothesis that jasmonates (novel anticancer agents) can induce death in mutated p53-expressing cells. Two clones of B-lymphoma cells were studied, one expressing wild-type (wt) p53 and the other expressing mutated p53. Jasmonic acid and methyl jasmonate (0.25–3 mM) were each equally cytotoxic to both clones, whereas mutant p53-expressing cells were resistant to treatment with the radiomimetic agent neocarzinostatin and the chemotherapeutic agent bleomycin. Neocarzinostatin and bleomycin induced an elevation in the p53 levels in wt p53-expressing cells, whereas methyl jasmonate did not. Methyl jasmonate induced mostly apoptotic death in the wt p53-expressing cells, while no signs of early apoptosis were detected in mutant p53-expressing cells. In contrast, neocarzinostatin and bleomycin induced death only in wt p53-expressing cells, in an apoptotic mode. Methyl jasmonate induced a rapid depletion of ATP in both clones. In both clones, oligomycin (a mitochondrial ATP synthase inhibitor) did not increase ATP depletion induced by methyl jasmonate, whereas inhibition of glycolysis with 2-deoxyglucose did. High glucose levels protected both clones from methyl jasmonate-induced ATP depletion (and reduced methyl jasmonate-induced cytotoxicity), whereas high levels of pyruvate did not. These results suggest that methyl jasmonate induces ATP depletion mostly by compromising oxidative phosphorylation in the mitochondria. In conclusion, jasmonates can circumvent the resistance of mutant p53-expressing cells towards chemotherapy by inducing a nonapoptotic cell death. PMID:16170329

  4. Cognitive Control, Reward Related Decision Making and Outcomes of Late-Life Depression Treated with an Antidepressant

    PubMed Central

    Alexopoulos, George S.; Manning, Kevin; Kanellopoulos, Dora; McGovern, Amanda; Seirup, Joanna K.; Banerjee, Samprit; Gunning, Faith

    2015-01-01

    Background Executive processes consist of at least two sets of functions: one concerned with cognitive control and the other with reward-related decision making. Abnormal performance in both sets occurs in late-life depression. This study tested the hypothesis that only abnormal performance in cognitive control tasks predicts poor outcomes of late-life depression treated with escitalopram. Methods We studied older subjects with major depression (N=53) and non-depressed subjects (N=30). Executive functions were tested with the Iowa Gambling Test (IGT), Stroop Color/Word test, Tower of London, and Dementia Rating Scale-Initiation/Perseveration Domain (DRS-IP). After a 2-week placebo washout, depressed subjects received escitalopram (target daily dose: 20 mg) for 12 weeks. Results There were no significant differences between depressed and non-depressed subjects on executive function tests. Hierarchical cluster analysis of depressed subjects identified a Cognitive Control Cluster (abnormal Stroop, Tower, DRS-IP), a Reward-Related Cluster (IGT), and an Executively Unimpaired Cluster. Decline in depression was greater in the Executively Unimpaired (t=−2.09, df=331, p=0.0375) and the Reward-Related Cluster (t=−2.33, df=331,p=0.0202) than the Cognitive Control Cluster. The Executively Unimpaired Cluster (t=2.17, df=331, p=0.03) and the Reward-Related Cluster (t=2.03, df=331, p=0.0433) had a higher probability of remission than the Cognitive Control Cluster. Conclusions Dysfunction of cognitive control functions, but not reward-related decision making, may influence the decline of symptoms and the probability of remission of late-life depression treated with escitalopram. If replicated, simple to administer cognitive control tests may be used to select depressed older patients at risk for poor outcomes to SSRIs who may require structured psychotherapy. PMID:26169527

  5. Characteristics of early- and late-onset rapid eye movement sleep behavior disorder in China: a case-control study.

    PubMed

    Zhou, Junying; Zhang, Jihui; Du, Lina; Li, Zhe; Li, Yun; Lei, Fei; Wing, Yun-Kwok; Kushida, Clete A; Zhou, Dong; Tang, Xiangdong

    2014-06-01

    To investigate demography and clinic and polysomnographic characteristics in Chinese rapid eye movement (REM) sleep behavior disorder (RBD) patients across onset ages. Ninety consecutive patients fulfilling the criteria for RBD were recruited for study in our sleep center. Patients were separated into early- and late-onset groups according to age when symptoms began (< or =50 and >50 years, respectively). Ninety age- and gender-matched healthy subjects served as controls. All subjects were interviewed for their clinical history, completed an RBD questionnaire, and underwent an overnight video polysomnography assessment. Demographics, comorbidities, scores on the RBD questionnaire, sleep architecture, and EMG activity were compared between the patients and controls and between the early- and late-onset groups. Of all RBD patients, 63 were male, and mean age of RBD onset was 54.3±15.7 years. In 25 patients (28%), RBD was secondary and associated with neurodegenerative disease, narcolepsy or antidepressant use. Twenty-three patients (26%) had early-onset RBD and 67 (74%) were in the late-onset group. RBD patients had significantly more comorbidities, dreams and dream-enacting behaviors, and poorer sleep quality than did controls. The early-onset group had a high proportion of females (48%) and an increased proportion of cases associated with narcolepsy. The early-onset group also had fewer movements, lower EMG activity during REM sleep, and better sleep quality when compared to the late-onset group. EMG activity was positively correlated with age of onset. The mean follow-up time was 1.57±0.82 years, and four patients in the late-onset group were subsequently diagnosed with neurodegenerative diseases. Stratifying patients into early and late-onset RBD revealed different characteristics from those previously described as typical for RBD. EMG activity during REM sleep was positively correlated with age of onset. We suggest that it will be valuable to explore the

  6. The Late Variscan control on the location and asymmetry of the Upper Rhine Graben

    NASA Astrophysics Data System (ADS)

    Grimmer, J. C.; Ritter, J. R. R.; Eisbacher, G. H.; Fielitz, W.

    2017-04-01

    rocks on the eastern graben shoulder in contrast to the predominantly low-grade metamorphic to unmetamorphosed sedimentary-volcanic rocks exposed on the western shoulder. Although between c. 310 and 270 Ma NE-trending Permocarboniferous volcanic-sedimentary basins of the URG area subsided along upper crustal faults that mimic the trend of Variscan faults, initial broad lithospheric cooling from c. 270-200 Ma led to subsidence of a distinctly NNE- to SSW-oriented embayment that was probably underlain by thinner Palaeozoic crust in the area of the NNE-trending East Rhine Detachment. After re-emergence of the platform above sea level in late Mesozoic times, the deep-reaching W-dipping "extensional defects" of the East Rhine Detachment exerted a primary lithospheric scale control on both location and cross-sectional asymmetry of the Cenozoic graben structure. NE- and NW-striking, strongly altered and more shallow rooted Permocarboniferous or Mesozoic faults exerted secondary upper crustal controls on transfer faults and the accommodation zones near the terminations and segment boundaries of the URG. Deep crustal to upper lithospheric asymmetries continue to influence the neotectonic setting of the URG, such as westward rising earthquake hypocentres. Seismic activity along the URG appears to be part of a >600 km long zone that delimits the trailing edge of a SW-moving lithospheric block. In the URG area, NE-SW-oriented seismic anisotropy at sublithospheric depths of c. 60-80 km suggest active mantle flow in this direction as a possible driving force for the reactivation of pre-graben lithospheric shear zones.

  7. Early versus late surfactant treatment in preterm infants of 27 to 32 weeks' gestational age: a multicenter controlled clinical trial.

    PubMed

    Gortner, L; Wauer, R R; Hammer, H; Stock, G J; Heitmann, F; Reiter, H L; Kühl, P G; Möller, J C; Friedrich, H J; Reiss, I; Hentschel, R; Jorch, G; Hieronimi, G; Kuhls, E

    1998-11-01

    To investigate whether early (<1 hour after birth) surfactant administration would be superior to late treatment (2-6 hours after birth) in preterm infants. Randomized controlled multicenter clinical trial. Prenatal randomization of all infants of 27 to 32 weeks' gestational age stratified by center after parental informed consent. Early treatment: 100 mg/kg body weight bovine surfactant (SF-RI1, Alveofact; Dr K. Thomae, Biberach, Germany) to infants requiring intubation after birth. Late treatment: identical dosage to infants requiring intubation up to 6 hours of age with the fraction of inspired oxygen >0.4 at 2 to 6 hours after birth. Primary endpoint: the time on mechanical ventilation. Main secondary endpoints: mortality, bronchopulmonary dysplasia, intraventricular hemorrhage >/=grade III, and periventricular leukomalacia. Sample size calculation: at least 280 infants to prove superiority of either approach (alpha = 0.05; beta = 0.90). Enrollment of 317 infants, 154 randomized to early surfactant treatment, 163 to late surfactant treatment. Study infants (all following data intent-to-treat groups: early versus late surfactant) were similar with respect to: gestational age, 29.5 +/- 1.6 weeks versus 29.7 +/- 1.6 weeks; birth weight, 1227 +/- 367 g versus 1269 +/- 334 g; and the rate of prenatal corticosteroids, 79.9% versus 72.8%. Duration of mechanical ventilation: 3 days (0-8) versus 2 days (0-6) (median, interquartile); further outcome variables: death or bronchopulmonary dysplasia (day 28) 25.9% versus 23.9%, mortality 3.2% versus 1.8%, intraventricular hemorrhage >/=grade III 6.5% versus 3.7%, and periventricular leukomalacia 5.2% versus 5.5% not differing statistically. In preterm infants with a high rate of prenatal glucocorticoids, early surfactant administration was not found to be superior to late treatment in terms of relevant outcome variables.

  8. Deficiencies in Jasmonate-Mediated Plant Defense Reveal Quantitative Variation in Botrytis cinerea Pathogenesis

    PubMed Central

    Rowe, Heather C.; Walley, Justin W.; Corwin, Jason; Chan, Eva K.-F.; Dehesh, Katayoon; Kliebenstein, Daniel J.

    2010-01-01

    Despite the described central role of jasmonate signaling in plant defense against necrotrophic pathogens, the existence of intraspecific variation in pathogen capacity to activate or evade plant jasmonate-mediated defenses is rarely considered. Experimental infection of jasmonate-deficient and jasmonate-insensitive Arabidopsis thaliana with diverse isolates of the necrotrophic fungal pathogen Botrytis cinerea revealed pathogen variation for virulence inhibition by jasmonate-mediated plant defenses and induction of plant defense metabolites. Comparison of the transcriptional effects of infection by two distinct B. cinerea isolates showed only minor differences in transcriptional responses of wild-type plants, but notable isolate-specific transcript differences in jasmonate-insensitive plants. These transcriptional differences suggest B. cinerea activation of plant defenses that require plant jasmonate signaling for activity in response to only one of the two B. cinerea isolates tested. Thus, similar infection phenotypes observed in wild-type plants result from different signaling interactions with the plant that are likely integrated by jasmonate signaling. PMID:20419157

  9. Tectonically controlled fan delta and submarine fan sedimentation of late Miocene age, southern Temblor Range, California

    USGS Publications Warehouse

    Ryder, Robert T; Thomson, Alan

    1989-01-01

    The Santa Margarita Formation in the southern Temblor Range, composed of conglomerate and subordinate sandstone, evolved as a large complex of fan deltas and submarine fans in late Miocene time. An 80 to 90-m.y.-old granitic basement of the Salinian block and an accompanying 23.5-m.y.-old volcanic field now located in the northern Gabilan Range and the Pinnacles area, respectively, were the primary source terranes. In general, the fan deltas crop out along the west side of the southern Temblor Range, whereas the proximal parts of the submarine fans crop out along the east side of the range. The fan deltas consist of subaerial topset beds and low-angle basinward-dipping subaqueous foreset beds. Strata interpreted to be topset beds are composed largely of conglomerate with thick to very thick horizontal beds and matrix-supported clasts. Most of the thick to very thick conglomerate beds are internally massive and disorganized. Strata interpreted as foreset beds are composed of thick-bedded, large-scale, low-angle, cross-stratified conglomerate and sandstone units which commonly are internally massive. Abundant molluskan macrofossils such as Ostrea and Pecten are present in the subaqueous foreset beds; many have been displaced downslope from their original site of deposition. Conglomerate- and sandstone-filled submarine canyons, through which coarse-grained detritus was transported to the adjacent submarine fans, locally have cut into the foreset beds of the fan deltas. These submarine canyon deposits are generally better stratified than adjacent foreset-bed deposits, and they consist of thick horizontal beds, internally massive or normally graded, arranged in fining- and thinning-upward sequences. Isolated and composite conglomerate- and sandstone-filled channels, which crop out on the east flank of the southern Temblor Range, are interpreted as proximal submarine-fan channel deposits. These channel-form conglomerate and sandstone deposits are characterized by thick

  10. Tectonically controlled fan delta and submarine fan sedimentation of late Miocene age, southern Temblor Range, California

    USGS Publications Warehouse

    Ryder, Robert T; Thomson, Alan

    1989-01-01

    The Santa Margarita Formation in the southern Temblor Range, composed of conglomerate and subordinate sandstone, evolved as a large complex of fan deltas and submarine fans in late Miocene time. An 80 to 90-m.y.-old granitic basement of the Salinian block and an accompanying 23.5-m.y.-old volcanic field now located in the northern Gabilan Range and the Pinnacles area, respectively, were the primary source terranes. In general, the fan deltas crop out along the west side of the southern Temblor Range, whereas the proximal parts of the submarine fans crop out along the east side of the range. The fan deltas consist of subaerial topset beds and low-angle basinward-dipping subaqueous foreset beds. Strata interpreted to be topset beds are composed largely of conglomerate with thick to very thick horizontal beds and matrix-supported clasts. Most of the thick to very thick conglomerate beds are internally massive and disorganized. Strata interpreted as foreset beds are composed of thick-bedded, large-scale, low-angle, cross-stratified conglomerate and sandstone units which commonly are internally massive. Abundant molluskan macrofossils such as Ostrea and Pecten are present in the subaqueous foreset beds; many have been displaced downslope from their original site of deposition. Conglomerate- and sandstone-filled submarine canyons, through which coarse-grained detritus was transported to the adjacent submarine fans, locally have cut into the foreset beds of the fan deltas. These submarine canyon deposits are generally better stratified than adjacent foreset-bed deposits, and they consist of thick horizontal beds, internally massive or normally graded, arranged in fining- and thinning-upward sequences. Isolated and composite conglomerate- and sandstone-filled channels, which crop out on the east flank of the southern Temblor Range, are interpreted as proximal submarine-fan channel deposits. These channel-form conglomerate and sandstone deposits are characterized by thick

  11. The effect of extraction of third molars on late lower incisor crowding: a randomized controlled trial.

    PubMed

    Harradine, N W; Pearson, M H; Toth, B

    1998-05-01

    The problem of late mandibular incisor crowding is a well established phenomenon, the cause of which has been the substance of considerable debate over the years. A central issue is the possible role of the third molars though no definitive conclusions have been consistently drawn. This prospective study was designed to investigate the effects of randomly assigned early extraction of third molars on late crowding of the mandibular incisors. One-hundred-and-sixty-four patients entered the study from 1984 following completion of retention after orthodontic treatment. Seventy-seven patients (47%) returned for records up to a mean of 66 months later, and their start and finish study casts were digitized on a reflex microscope to determine Little's index of irregularity, intercanine width and arch length. Forty-four of the patients had been randomized to have third molars removed. There was no evidence of responder bias. Where third molars were extracted the mean increase in lower labial segment irregularity was reduced by 1.1 mm from a mean of 2.1 mm for the group where third molars were retained (P = 0.15, not statistically significant). This difference was also not considered to be clinically significant. The principal conclusion drawn from this randomized prospective study is that the removal of third molars to reduce or prevent late incisor crowding cannot be justified.

  12. Late reactions in food-allergic children and adolescents after double-blind, placebo-controlled food challenges.

    PubMed

    Saleh-Langenberg, J; Flokstra-de Blok, B M J; AlAgla, N; Kollen, B J; Dubois, A E J

    2016-07-01

    The time during which children are observed following a double-blind, placebo-controlled food challenge (DBPCFC) varies in clinical practice. There are little data on late reactions (LRs) following DBPCFCs. Therefore, we determined the prevalence, severity and clinical characteristics of late reactions in food-allergic children and adolescents after DBPCFC, and ascertained which factors are associated with, and may predict, LRs. Logistic regression analyses were performed to investigate which factors were associated with LRs and to develop the association and prediction models. A total of 1142 children underwent DBPCFCs (child-test combinations). Of these 1142 child-test combinations, 400 reported LRs following the DBPCFC. LRs in food-allergic children after DBPCFC are poorly predictable and are generally not severe. All LRs, including those on the placebo day, are more frequently reported in younger children. Children who do not experience severe immediate reactions may be safely discharged home 2 h after a DBPCFC.

  13. Jasmonate Hormone: Regulating Synthesis of Reduced Carbon Compounds in Plants

    SciTech Connect

    Browse, John

    2016-05-13

    Our original interest in understanding the role of jasmonate (JA) in regulating the final stages of stamen and pollen development led to our discovery of the JAZ repressors, and the molecular mechanism of JA action is now a second important focus of our research. The specific goals for this grant period are to: 1. Investigate the generation and clearance of the hormone with emphasis on the regulation of the OPR3 enzyme and the hydrolysis of JA-Ile. 2. Use dominant-negative and overexpression constructs to explore the role of the MYC5 transcription factor in initiating and regulating JA responses. 3. Investigate specific JAZ protein interactions that will help us to recognize and understand the extended network of processes, such as sulfur nutrition, that interface with JA signaling. The COI1 F-Box protein is a JA-Ile coreceptor and coi1 mutant plants lack JA responses. We have tested the possibility that sites of JA action can be probed by using tissue-specific promoters to drive expression of a COI1-YFP fusion protein in coi1 mutant plants deficient in stamen and pollen function. When we expressed COI1 behind a filament-specific promoter (from the DAD1 gene), filament elongation was restored but not anther dehiscence or pollen function. Three tapetum specific promoters, all failed to restore any of these three functions but, unexpectedly, a promoter active in the stomium and epidermal cells, restored both pollen function and anther dehiscence. Most importantly, our results demonstrate the power of promoter::COI1-YFP constructs in revealing the primary sites of JA-regulated gene expression that control developmental and other responses in neighboring tissues. We now plan to use this new tool to test current hypotheses about JA action in other organs of the plant. The MYC2, MYC3, and MYC4 proteins are the primary transcription factors initiating defense and root growth responses to JA signaling. However, transgenic plants overexpressing these proteins do not show

  14. Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.

    PubMed

    Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi

    2005-02-01

    The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems.

  15. The influence of jasmonic acid on biophysical properties of potato leaf protoplasts and roots.

    PubMed

    Vilhar, B; Ravnikar, M; Schara, M; Nemec, M; Gogala, N

    1991-12-01

    Jasmonic acid (JA) and its derivatives are a novel group of plant endogenous growth regulators. In our experiments some new data about the physiological effects of JA were obtained using electron paramagnetic resonance spectroscopy. Experiments were performed on potato plants (Solanum tuberosum L. cv. Vesna) grown in vitro. Different quantities of JA (0.1-10 μM) were added to the growth medium. Root samples of plants grown on media supplemented with JA showed a more rapid spin probe N-oxyl-2,2,6,6-tetramethyl piperidine reduction than the control plants, which is a possible indicator of altered root permeability. Samples of leaf protoplasts were probed with methyl ester of 5-doxyl-haxadecanoic acid. We observed a membrane fluidity decrease in protoplasts isolated from plants grown on higher concentrations of JA (1 and 10 μM).

  16. Methyl jasmonate reduces chilling injury and maintains postharvest quality of mango fruit.

    PubMed

    González-Aguilar, G A; Fortiz, J; Cruz, R; Baez, R; Wang, C Y

    2000-02-01

    Exposure of mango (Mangifera indica cv. Tommy Atkins) fruit to methyl jasmonate (MJ) vapors (10(-)(4) M) for 24 h at 25 degrees C reduced chilling injury during subsequent storage for 21 days at 7 degrees C and after 5 days of shelf life at 20 degrees C. The chilling tolerance induced by MJ was positively correlated with the reduction in the percent ion leakage of mango tissue. The overall quality of MJ-treated fruit was also better than that of control fruit. MJ treatment increased the total soluble solids but did not affect titratable acidity or pH. MJ also did not change the normal climacteric rise in respiration, water loss, and softening rates. The efficacy of MJ to reduce chilling injury and decay of mango could be related to the tolerance induced at low temperature. It was concluded that MJ treatment may prevent chilling injury symptoms of mango without altering the ripening process.

  17. Methyl jasmonate stimulates jaceosidin and hispidulin production in cell cultures of Saussurea medusa.

    PubMed

    Fu, Chun-xiang; Cheng, Li-qin; Lv, Xiao-fen; Zhao, De-xiu; Ma, Fengshan

    2006-07-01

    Cell cultures of Saussurea medusa produce valuable secondary metabolites, and jaceosidin and hispidulin are the major bioactive compounds. In the present study, the cultures were challenged by methyl jasmonate (MJ). The highest jaceosidin and hispidulin concentrations (65.2 +/- 3.67 mg/L and 12.3 +/- 0.47 mg/L) were achieved with 5 microM MJ added to 9-d-old subcultures, being 2.2-fold and 4.2-fold, respectively, higher than those from controls. The elicitor had little influence on cell growth, indicating that the changed biological processes did not include alterations in cell division. Furthermore, we observed that the activities of phenylalanine ammonia lyase were transiently increased after treatment with MJ, which suggests that this elicitor modifies jaceosidin and hispidulin production by regulating the phenylpropanoid pathway.

  18. Preharvest Application of Methyl Jasmonate as Elicitor Improves Yield and Phenolic Content of Artichoke.

    PubMed

    Martínez Esplá, Alejandra; Valero, Daniel; Martinez-Romero, Domingo; Castillo, Salvador; Giménez, María José; García-Pastor, María Emma; Serrano, Maria; Zapata, Pedro Javier

    2017-09-29

    The effects of methyl jasmonate (MeJa) treatment, as elicitor, of artichoke plants [Cynara cardunculus var. scolymus (L.) Fiori], on yield and quality attributes of artichokes, especially those related with individual phenolic content and antioxidant activity, at two harvest dates and along storage, were analyzed in this research. Plants treated gave higher yield of artichokes in comparison to control plants, with 0.55 kg more per plant. MeJa treatment also increased artichoke quality and phenolic content in the edible fraction at harvest and during storage at 2 °C for 28 days, due to accumulation of hydroxycinnamic acids and luteolin derivatives. In addition, antioxidant activity was enhanced by MeJa treatment and correlated with total phenolic content. Results suggest that MeJa foliar application could be a simple and practice tool to improve yield and phytochemical content on artichokes, being elicitation a cheap and environmental friendly procedure to improve the health beneficial effects of artichoke consumption.

  19. Jasmonate in plant defence: sentinel or double agent?

    PubMed

    Yan, Chun; Xie, Daoxin

    2015-12-01

    Plants and their biotic enemies, such as microbial pathogens and herbivorous insects, are engaged in a desperate battle which would determine their survival-death fate. Plants have evolved efficient and sophisticated systems to defend against such attackers. In recent years, significant progress has been made towards a comprehensive understanding of inducible defence system mediated by jasmonate (JA), a vital plant hormone essential for plant defence responses and developmental processes. This review presents an overview of JA action in plant defences and discusses how microbial pathogens evade plant defence system through hijacking the JA pathway.

  20. Cell length growth patterns in fission yeast reveal a novel size control mechanism operating in late G2 phase.

    PubMed

    Horváth, Anna; Rácz-Mónus, Anna; Buchwald, Peter; Sveiczer, Ákos

    2016-09-01

    Because cylindrically shaped fission yeast cells grow exclusively at their tips, cell volume is proportional to length and can be easily monitored by time-lapse microscopy. Here, we analysed the growth pattern of individual cells from several fission yeast strains to determine the growth function that describes them most adequately and to perform size control studies. The growth pattern of most cells during their growth period is best described by a bilinear function (i.e., two linear segments of different growth rates separated by a rate-change point). Linear growth patterns were also observed in several cases, but exponential ones only rarely. Since the bilinear patterns are separated into two segments by a breakpoint, we examined the existence of size control by regression analyses of the appropriate growth parameters in both segments. This confirmed the existence of known size controls in late G1, mid-G2 and late G2 during the fission yeast cycle. The present analyses also revealed that, contrary to the commonly accepted current view, late G2 size control is a general characteristic third event in the cycle. The level of the critical late G2 size that needs to be reached in an individual fission yeast cell is influenced by the growth rate of the cell in a manner similar to budding yeast, suggesting an evolutionary conserved mechanism. The present study of individual cell growth patterns in wild-type and several cell cycle mutant fission yeast strains confirmed that, for most cells, growth is best described by a bilinear function. Three different size control mechanisms were found to operate in the different strains, and, as a novel observation, cell size was always found to be monitored before mitotic onset, irrespective of the existence of any earlier size checkpoints. Studying the pattern of growth and the mechanism of size control helps to clarify the connections between cell growth and division, since their coordination must work properly to maintain size

  1. Genome-wide characterization of JASMONATE-ZIM DOMAIN transcription repressors in wheat (Triticum aestivum L.).

    PubMed

    Wang, Yukun; Qiao, Linyi; Bai, Jianfang; Wang, Peng; Duan, Wenjing; Yuan, Shaohua; Yuan, Guoliang; Zhang, Fengting; Zhang, Liping; Zhao, Changping

    2017-02-13

    The JASMONATE-ZIM DOMAIN (JAZ) repressor family proteins are jasmonate co-receptors and transcriptional repressor in jasmonic acid (JA) signaling pathway, and they play important roles in regulating the growth and development of plants. Recently, more and more researches on JAZ gene family are reported in many plants. Although the genome sequencing of common wheat (Triticum aestivum L.) and its relatives is complete, our knowledge about this gene family remains vacant. Fourteen JAZ genes were identified in the wheat genome. Structural analysis revealed that the TaJAZ proteins in wheat were as conserved as those in other plants, but had structural characteristics. By phylogenetic analysis, all JAZ proteins from wheat and other plants were clustered into 11 sub-groups (G1-G11), and TaJAZ proteins shared a high degree of similarity with some JAZ proteins from Aegliops tauschii, Brachypodium distachyon and Oryza sativa. The Ka/Ks ratios of TaJAZ genes ranged from 0.0016 to 0.6973, suggesting that the TaJAZ family had undergone purifying selection in wheat. Gene expression patterns obtained by quantitative real-time PCR (qRT-PCR) revealed differential temporal and spatial regulation of TaJAZ genes under multifarious abiotic stress treatments of high salinity, drought, cold and phytohormone. Among these, TaJAZ7, 8 and 12 were specifically expressed in the anther tissues of the thermosensitive genic male sterile (TGMS) wheat line BS366 and normal control wheat line Jing411. Compared with the gene expression patterns in the normal wheat line Jing411, TaJAZ7, 8 and 12 had different expression patterns in abnormally dehiscent anthers of BS366 at the heading stage 6, suggesting that specific up- or down-regulation of these genes might be associated with the abnormal anther dehiscence in TGMS wheat line. This study analyzed the size and composition of the JAZ gene family in wheat, and investigated stress responsive and differential tissue-specific expression profiles of each

  2. Jasmonate signaling is activated in the very early stages of iron deficiency responses in rice roots.

    PubMed

    Kobayashi, Takanori; Itai, Reiko Nakanishi; Senoura, Takeshi; Oikawa, Takaya; Ishimaru, Yasuhiro; Ueda, Minoru; Nakanishi, Hiromi; Nishizawa, Naoko K

    2016-07-01

    Under low iron availability, plants induce the expression of various genes involved in iron uptake and translocation at the transcriptional level. This iron deficiency response is affected by various plant hormones, but the roles of jasmonates in this response are not well-known. We investigated the involvement of jasmonates in rice iron deficiency responses. High rates of jasmonate-inducible genes were induced during the very early stages of iron deficiency treatment in rice roots. Many jasmonate-inducible genes were also negatively regulated by the ubiquitin ligases OsHRZ1 and OsHRZ2 and positively regulated by the transcription factor IDEF1. Ten out of 35 genes involved in jasmonate biosynthesis and signaling were rapidly induced at 3 h of iron deficiency treatment, and this induction preceded that of known iron deficiency-inducible genes involved in iron uptake and translocation. Twelve genes involved in jasmonate biosynthesis and signaling were also upregulated in HRZ-knockdown roots. Endogenous concentrations of jasmonic acid and jasmonoyl isoleucine tended to be rapidly increased in roots in response to iron deficiency treatment, whereas these concentrations were higher in HRZ-knockdown roots under iron-sufficient conditions. Analysis of the jasmonate-deficient cpm2 mutant revealed that jasmonates repress the expression of many iron deficiency-inducible genes involved in iron uptake and translocation under iron sufficiency, but this repression is partly canceled under an early stage of iron deficiency. These results indicate that jasmonate signaling is activated during the very early stages of iron deficiency, which is partly regulated by IDEF1 and OsHRZs.

  3. New Clothes for the Jasmonic Acid Receptor COI1: Delayed Abscission, Meristem Arrest and Apical Dominance

    PubMed Central

    Kim, Joonyup; Dotson, Bradley; Rey, Camila; Lindsey, Joshua; Bleecker, Anthony B.; Binder, Brad M.; Patterson, Sara E.

    2013-01-01

    In a screen for delayed floral organ abscission in Arabidopsis, we have identified a novel mutant of CORONATINE INSENSITIVE 1 (COI1), the F-box protein that has been shown to be the jasmonic acid (JA) co-receptor. While JA has been shown to have an important role in senescence, root development, pollen dehiscence and defense responses, there has been little focus on its critical role in floral organ abscission. Abscission, or the detachment of organs from the main body of a plant, is an essential process during plant development and a unique type of cell separation regulated by endogenous and exogenous signals. Previous studies have indicated that auxin and ethylene are major plant hormones regulating abscission; and here we show that regulation of floral organ abscission is also controlled by jasmonic acid in Arabidopsis thaliana. Our characterization of coi1-1 and a novel allele (coi1-37) has also revealed an essential role in apical dominance and floral meristem arrest. In this study we provide genetic evidence indicating that delayed abscission 4 (dab4-1) is allelic to coi1-1 and that meristem arrest and apical dominance appear to be evolutionarily divergent functions for COI1 that are governed in an ecotype-dependent manner. Further characterizations of ethylene and JA responses of dab4-1/coi1-37 also provide new information suggesting separate pathways for ethylene and JA that control both floral organ abscission and hypocotyl growth in young seedlings. Our study opens the door revealing new roles for JA and its interaction with other hormones during plant development. PMID:23573263

  4. Regulation of extrafloral nectar secretion by jasmonates in lima bean is light dependent

    PubMed Central

    Radhika, Venkatesan; Kost, Christian; Mithöfer, Axel; Boland, Wilhelm

    2010-01-01

    To maximize fitness, plants need to perceive changes in their light environment and adjust their physiological responses accordingly. Whether and how such changes also affect the regulation of their defense responses against herbivores remains largely unclear. We addressed this issue by studying the secretion of extrafloral nectar (EFN) in lima bean (Phaseolus lunatus), which is known to be activated by the phytohormone jasmonic acid (JA) and functions as an indirect defense mechanism against herbivores. We found that the plant’s EFN secretion in response to JA was light dependent: In the dark, JA reduced EFN secretion, whereas under light conditions, JA induced EFN secretion relative to controls. This modulation was affected by the light’s spectral composition [i.e., ratio of red to far-red (R:FR) radiation], but not light intensity. These findings demonstrate a unique differential effect of JA on EFN secretion depending on the ambient light conditions. Interestingly, treatment with the isoleucine–JA conjugate (JA–Ile) enhanced EFN secretion under light conditions yet did not reduce EFN secretion in the dark. Moreover, inhibition of Ile biosynthesis in light-exposed plants significantly decreased the EFN secretion rate. This reduction could be recovered by additional application of JA–Ile, suggesting that JA–Ile is the active compound required to up-regulate EFN secretion. Finally, experiments with mechanically damaged plants revealed that light was required for the formation of JA–Ile, but not of JA. These results demonstrate that in lima bean, the light environment modulates the plant’s response to jasmonates as well as JA–Ile biosynthesis, which controls the subsequent EFN secretion. PMID:20855624

  5. Induced production of 1-methoxy-indol-3-ylmethyl glucosinolate by jasmonic acid and methyl jasmonate in sprouts and leaves of pak choi (Brassica rapa ssp. chinensis).

    PubMed

    Wiesner, Melanie; Hanschen, Franziska S; Schreiner, Monika; Glatt, Hansruedi; Zrenner, Rita

    2013-07-18

    Pak choi plants (Brassica rapa ssp. chinensis) were treated with different signaling molecules methyl jasmonate, jasmonic acid, linolenic acid, and methyl salicylate and were analyzed for specific changes in their glucosinolate profile. Glucosinolate levels were quantified using HPLC-DAD-UV, with focus on induction of indole glucosinolates and special emphasis on 1-methoxy-indol-3-ylmethyl glucosinolate. Furthermore, the effects of the different signaling molecules on indole glucosinolate accumulation were analyzed on the level of gene expression using semi-quantitative realtime RT-PCR of selected genes. The treatments with signaling molecules were performed on sprouts and mature leaves to determine ontogenetic differences in glucosinolate accumulation and related gene expression. The highest increase of indole glucosinolate levels, with considerable enhancement of the 1-methoxy-indol-3-ylmethyl glucosinolate content, was achieved with treatments of sprouts and mature leaves with methyl jasmonate and jasmonic acid. This increase was accompanied by increased expression of genes putatively involved in the indole glucosinolate biosynthetic pathway. The high levels of indole glucosinolates enabled the plant to preferentially produce the respective breakdown products after tissue damage. Thus, pak choi plants treated with methyl jasmonate or jasmonic acid, are a valuable tool to analyze the specific protection functions of 1-methoxy-indole-3-carbinole in the plants defense strategy in the future.

  6. Induced Production of 1-Methoxy-indol-3-ylmethyl Glucosinolate by Jasmonic Acid and Methyl Jasmonate in Sprouts and Leaves of Pak Choi (Brassica rapa ssp. chinensis)

    PubMed Central

    Wiesner, Melanie; Hanschen, Franziska S.; Schreiner, Monika; Glatt, Hansruedi; Zrenner, Rita

    2013-01-01

    Pak choi plants (Brassica rapa ssp. chinensis) were treated with different signaling molecules methyl jasmonate, jasmonic acid, linolenic acid, and methyl salicylate and were analyzed for specific changes in their glucosinolate profile. Glucosinolate levels were quantified using HPLC-DAD-UV, with focus on induction of indole glucosinolates and special emphasis on 1-methoxy-indol-3-ylmethyl glucosinolate. Furthermore, the effects of the different signaling molecules on indole glucosinolate accumulation were analyzed on the level of gene expression using semi-quantitative realtime RT-PCR of selected genes. The treatments with signaling molecules were performed on sprouts and mature leaves to determine ontogenetic differences in glucosinolate accumulation and related gene expression. The highest increase of indole glucosinolate levels, with considerable enhancement of the 1-methoxy-indol-3-ylmethyl glucosinolate content, was achieved with treatments of sprouts and mature leaves with methyl jasmonate and jasmonic acid. This increase was accompanied by increased expression of genes putatively involved in the indole glucosinolate biosynthetic pathway. The high levels of indole glucosinolates enabled the plant to preferentially produce the respective breakdown products after tissue damage. Thus, pak choi plants treated with methyl jasmonate or jasmonic acid, are a valuable tool to analyze the specific protection functions of 1-methoxy-indole-3-carbinole in the plants defense strategy in the future. PMID:23873294

  7. Single nucleotide polymorphisms in the allene oxide synthase 2 gene are associated with field resistance to late blight in populations of tetraploid potato cultivars.

    PubMed

    Pajerowska-Mukhtar, Karolina; Stich, Benjamin; Achenbach, Ute; Ballvora, Agim; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhard; Ilarionova, Evgeniya; Bellin, Diana; Walkemeier, Birgit; Basekow, Rico; Kersten, Birgit; Gebhardt, Christiane

    2009-03-01

    The oomycete Phytophthora infestans causes late blight, the most relevant disease of potato (Solanum tuberosum) worldwide. Field resistance to late blight is a complex trait. When potatoes are cultivated under long day conditions in temperate climates, this resistance is correlated with late plant maturity, an undesirable characteristic. Identification of natural gene variation underlying late blight resistance not compromised by late maturity will facilitate the selection of resistant cultivars and give new insight in the mechanisms controlling quantitative pathogen resistance. We tested 24 candidate loci for association with field resistance to late blight and plant maturity in a population of 184 tetraploid potato individuals. The individuals were genotyped for 230 single nucleotide polymorphisms (SNPs) and 166 microsatellite alleles. For association analysis we used a mixed model, taking into account population structure, kinship, allele substitution and interaction effects of the marker alleles at a locus with four allele doses. Nine SNPs were associated with maturity corrected resistance (P < 0.001), which collectively explained 50% of the genetic variance of this trait. A major association was found at the StAOS2 locus encoding allene oxide synthase 2, a key enzyme in the biosynthesis of jasmonates, plant hormones that function in defense signaling. This finding supports StAOS2 as being one of the factors controlling natural variation of pathogen resistance.

  8. Single Nucleotide Polymorphisms in the Allene Oxide Synthase 2 Gene Are Associated With Field Resistance to Late Blight in Populations of Tetraploid Potato Cultivars

    PubMed Central

    Pajerowska-Mukhtar, Karolina; Stich, Benjamin; Achenbach, Ute; Ballvora, Agim; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhard; Ilarionova, Evgeniya; Bellin, Diana; Walkemeier, Birgit; Basekow, Rico; Kersten, Birgit; Gebhardt, Christiane

    2009-01-01

    The oomycete Phytophthora infestans causes late blight, the most relevant disease of potato (Solanum tuberosum) worldwide. Field resistance to late blight is a complex trait. When potatoes are cultivated under long day conditions in temperate climates, this resistance is correlated with late plant maturity, an undesirable characteristic. Identification of natural gene variation underlying late blight resistance not compromised by late maturity will facilitate the selection of resistant cultivars and give new insight in the mechanisms controlling quantitative pathogen resistance. We tested 24 candidate loci for association with field resistance to late blight and plant maturity in a population of 184 tetraploid potato individuals. The individuals were genotyped for 230 single nucleotide polymorphisms (SNPs) and 166 microsatellite alleles. For association analysis we used a mixed model, taking into account population structure, kinship, allele substitution and interaction effects of the marker alleles at a locus with four allele doses. Nine SNPs were associated with maturity corrected resistance (P < 0.001), which collectively explained 50% of the genetic variance of this trait. A major association was found at the StAOS2 locus encoding allene oxide synthase 2, a key enzyme in the biosynthesis of jasmonates, plant hormones that function in defense signaling. This finding supports StAOS2 as being one of the factors controlling natural variation of pathogen resistance. PMID:19139145

  9. A randomized, controlled trial of early versus late initiation of dialysis.

    PubMed

    Cooper, Bruce A; Branley, Pauline; Bulfone, Liliana; Collins, John F; Craig, Jonathan C; Fraenkel, Margaret B; Harris, Anthony; Johnson, David W; Kesselhut, Joan; Li, Jing Jing; Luxton, Grant; Pilmore, Andrew; Tiller, David J; Harris, David C; Pollock, Carol A

    2010-08-12

    In clinical practice, there is considerable variation in the timing of the initiation of maintenance dialysis for patients with stage V chronic kidney disease, with a worldwide trend toward early initiation. In this study, conducted at 32 centers in Australia and New Zealand, we examined whether the timing of the initiation of maintenance dialysis influenced survival among patients with chronic kidney disease. We randomly assigned patients 18 years of age or older with progressive chronic kidney disease and an estimated glomerular filtration rate (GFR) between 10.0 and 15.0 ml per minute per 1.73 m2 of body-surface area (calculated with the use of the Cockcroft-Gault equation) to planned initiation of dialysis when the estimated GFR was 10.0 to 14.0 ml per minute (early start) or when the estimated GFR was 5.0 to 7.0 ml per minute (late start). The primary outcome was death from any cause. Between July 2000 and November 2008, a total of 828 adults (mean age, 60.4 years; 542 men and 286 women; 355 with diabetes) underwent randomization, with a median time to the initiation of dialysis of 1.80 months (95% confidence interval [CI], 1.60 to 2.23) in the early-start group and 7.40 months (95% CI, 6.23 to 8.27) in the late-start group. A total of 75.9% of the patients in the late-start group initiated dialysis when the estimated GFR was above the target of 7.0 ml per minute, owing to the development of symptoms. During a median follow-up period of 3.59 years, 152 of 404 patients in the early-start group (37.6%) and 155 of 424 in the late-start group (36.6%) died (hazard ratio with early initiation, 1.04; 95% CI, 0.83 to 1.30; P=0.75). There was no significant difference between the groups in the frequency of adverse events (cardiovascular events, infections, or complications of dialysis). In this study, planned early initiation of dialysis in patients with stage V chronic kidney disease was not associated with an improvement in survival or clinical outcomes. (Funded by

  10. Prospective Study of Local Control and Late Radiation Toxicity After Intraoperative Radiation Therapy Boost for Early Breast Cancer

    SciTech Connect

    Chang, David W.; Marvelde, Luc te; Chua, Boon H.

    2014-01-01

    Purpose: To report the local recurrence rate and late toxicity of intraoperative radiation therapy (IORT) boost to the tumor bed using the Intrabeam System followed by external-beam whole-breast irradiation (WBI) in women with early-stage breast cancer in a prospective single-institution study. Methods and Materials: Women with breast cancer ≤3 cm were recruited between February 2003 and May 2005. After breast-conserving surgery, a single dose of 5 Gy IORT boost was delivered using 50-kV x-rays to a depth of 10 mm from the applicator surface. This was followed by WBI to a total dose of 50 Gy in 25 fractions. Patients were reviewed at regular, predefined intervals. Late toxicities were recorded using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring systems. Results: Fifty-five patients completed both IORT boost and external-beam WBI. Median follow-up was 3.3 years (range, 1.4-4.1 years). There was no reported locoregional recurrence or death. One patient developed distant metastases. Grade 2 and 3 subcutaneous fibrosis was detected in 29 (53%) and 8 patients (15%), respectively. Conclusions: The use of IORT as a tumor bed boost using kV x-rays in breast-conserving therapy was associated with good local control but a clinically significant rate of grade 2 and 3 subcutaneous fibrosis.

  11. Mosquito odorant receptor for DEET and methyl jasmonate

    PubMed Central

    Xu, Pingxi; Choo, Young-Moo; De La Rosa, Alyssa; Leal, Walter S.

    2014-01-01

    Insect repellents are important prophylactic tools for travelers and populations living in endemic areas of malaria, dengue, encephalitis, and other vector-borne diseases. DEET (N,N-diethyl-3-methylbenzamide) is a 6-decade-old synthetic repellent, which is still considered the gold standard of mosquito repellents. Mosquitoes use their sense of smell to detect DEET, but there are currently two hypotheses regarding its mode of action: activation of ionotropic receptor IR40a vs. odorant receptor(s). Here, we demonstrate that DEET, picaridin, insect repellent 3535, and p-menthan-3,8-diol activate the odorant receptor CquiOR136 of the southern house mosquito, Culex quinquefasciatus. Electrophysiological and behavioral assays showed that CquiIR40a knockdown had no significant effect on DEET detection and repellency. By contrast, reduction of CquiOR136 transcript levels led to a significant decrease in electroantennographic responses to DEET and a complete lack of repellency. Thus, direct activation of an odorant receptor, not an ionotropic receptor, is necessary for DEET reception and repellency in Culex mosquitoes. Interestingly, methyl jasmonate, a repellent derived from the nonvolatile jasmonic acid in the signaling pathway of plant defenses, elicited robust responses in CquiOR136•CquiOrco-expressing Xenopus oocytes, thus suggesting a possible link between natural products with long insect–plant evolutionary history and synthetic repellents. PMID:25349401

  12. NINJA connects the co-repressor TOPLESS to jasmonate signalling

    PubMed Central

    Pauwels, Laurens; Barbero, Gemma Fernández; Geerinck, Jan; Tilleman, Sofie; Grunewald, Wim; Pérez, Amparo Cuellar; Chico, José Manuel; Bossche, Robin Vanden; Sewell, Jared; Gil, Eduardo; García-Casado, Gloria; Witters, Erwin; Inzé, Dirk; Long, Jeff A.; De Jaeger, Geert; Solano, Roberto; Goossens, Alain

    2010-01-01

    Jasmonoyl-isoleucine (JA-Ile) is a plant hormone that regulates a broad array of plant defence and developmental processes1–5. JA-Ile-responsive gene expression is regulated by the transcriptional activator MYC2 that interacts physically with the jasmonate ZIM-domain (JAZ) repressor proteins. Upon JA-Ile perception, JAZ proteins are degraded and JA-Ile-dependent gene expression is activated6,7. The molecular mechanisms by which JAZ proteins repress gene expression remain unknown. Here we show that the JAZ proteins recruit the Groucho/Tup1-type co-repressor TOPLESS (TPL)8 and TPL-related proteins (TPRs) through a previously uncharacterized adaptor protein, designated Novel INteractor of JAZ (NINJA). NINJA acts as a transcriptional repressor of which the activity is mediated by a functional TPL-binding EAR repression motif. Accordingly, both NINJA and TPL proteins function as negative regulators of jasmonate responses. Our results point to TPL proteins as general co-repressors that affect multiple signalling pathways through the interaction with specific adaptor proteins. This new insight reveals how stress- and growth-related signalling cascades use common molecular mechanisms to regulate gene expression in plants. PMID:20360743

  13. NINJA connects the co-repressor TOPLESS to jasmonate signalling.

    PubMed

    Pauwels, Laurens; Barbero, Gemma Fernández; Geerinck, Jan; Tilleman, Sofie; Grunewald, Wim; Pérez, Amparo Cuéllar; Chico, José Manuel; Bossche, Robin Vanden; Sewell, Jared; Gil, Eduardo; García-Casado, Gloria; Witters, Erwin; Inzé, Dirk; Long, Jeff A; De Jaeger, Geert; Solano, Roberto; Goossens, Alain

    2010-04-01

    Jasmonoyl-isoleucine (JA-Ile) is a plant hormone that regulates a broad array of plant defence and developmental processes. JA-Ile-responsive gene expression is regulated by the transcriptional activator MYC2 that interacts physically with the jasmonate ZIM-domain (JAZ) repressor proteins. On perception of JA-Ile, JAZ proteins are degraded and JA-Ile-dependent gene expression is activated. The molecular mechanisms by which JAZ proteins repress gene expression remain unknown. Here we show that the Arabidopsis JAZ proteins recruit the Groucho/Tup1-type co-repressor TOPLESS (TPL) and TPL-related proteins (TPRs) through a previously uncharacterized adaptor protein, designated Novel Interactor of JAZ (NINJA). NINJA acts as a transcriptional repressor whose activity is mediated by a functional TPL-binding EAR repression motif. Accordingly, both NINJA and TPL proteins function as negative regulators of jasmonate responses. Our results point to TPL proteins as general co-repressors that affect multiple signalling pathways through the interaction with specific adaptor proteins. This new insight reveals how stress-related and growth-related signalling cascades use common molecular mechanisms to regulate gene expression in plants.

  14. Late Holocene methane rise caused by orbitally controlled increase in tropical sources.

    PubMed

    Singarayer, Joy S; Valdes, Paul J; Friedlingstein, Pierre; Nelson, Sarah; Beerling, David J

    2011-02-03

    Considerable debate surrounds the source of the apparently 'anomalous' increase of atmospheric methane concentrations since the mid-Holocene (5,000 years ago) compared to previous interglacial periods as recorded in polar ice core records. Proposed mechanisms for the rise in methane concentrations relate either to methane emissions from anthropogenic early rice cultivation or an increase in natural wetland emissions from tropical or boreal sources. Here we show that our climate and wetland simulations of the global methane cycle over the last glacial cycle (the past 130,000 years) recreate the ice core record and capture the late Holocene increase in methane concentrations. Our analyses indicate that the late Holocene increase results from natural changes in the Earth's orbital configuration, with enhanced emissions in the Southern Hemisphere tropics linked to precession-induced modification of seasonal precipitation. Critically, our simulations capture the declining trend in methane concentrations at the end of the last interglacial period (115,000-130,000 years ago) that was used to diagnose the Holocene methane rise as unique. The difference between the two time periods results from differences in the size and rate of regional insolation changes and the lack of glacial inception in the Holocene. Our findings also suggest that no early agricultural sources are required to account for the increase in methane concentrations in the 5,000 years before the industrial era.

  15. Dietary controls on extinction versus survival among avian megafauna in the late Pleistocene

    NASA Astrophysics Data System (ADS)

    Fox-Dobbs, Kena; Stidham, Thomas A.; Bowen, Gabriel J.; Emslie, Steven D.; Koch, Paul L.

    2006-08-01

    The late Pleistocene extinction decimated terrestrial megafaunal communities in North America, but did not affect marine mammal populations. In coastal regions, marine megafauna may have provided a buffer that allowed some large predators or scavengers, such as California condors (Gymnogyps californianus), to survive into the Holocene. To track the influence of marine resources on avifaunas we analyzed the carbon, nitrogen, and hydrogen isotope composition of collagen from late Pleistocene vultures and raptors, including species that survived the extinction (condor, bald eagle, golden eagle) and extinct species (teratorn, black vulture). At the Rancho La Brea and McKittrick tar pits of southern California, isotope values for extinct teratorns (Teratornis merriami, n = 10) and black vultures (Coragyps occidentalis, n = 8) show that they fed entirely in a terrestrial C3 ecosystem. In contrast, La Brea condors cluster into two groups, one with a terrestrial diet (n = 4), and the other with a strong marine influence (n = 5). At localities in the American southwest, Texas, and Florida, where condors became extinct, they have isotope values indicating entirely terrestrial diets (n = 10). Our results suggest that dependence upon terrestrial megafaunal carrion as a food source led to the extinction of inland California condor populations and coastal populations of teratorns and black vultures at the Pleistocene-Holocene boundary, whereas use of marine foods allowed coastal condor populations to survive.

  16. Controls on body size during the Late Permian mass extinction event.

    PubMed

    He, W-H; Twitchett, R J; Zhang, Y; Shi, G R; Feng, Q-L; Yu, J-X; Wu, S-B; Peng, X-F

    2010-12-01

    This study examines the morphological responses of Late Permian brachiopods to environmental changes. Quantitative analysis of body size data from Permian-Triassic brachiopods has demonstrated significant, directional changes in body size before, during and after the Late Permian mass extinction event. Brachiopod size significantly reduced before and during the extinction interval, increased for a short time in more extinction-resistant taxa in the latter stages of extinction and then dramatically reduced again across the Permian/Triassic boundary. Relative abundances of trace elements and acritarchs demonstrate that the body size reductions which happened before, during and after extinction were driven by primary productivity collapse, whereas declining oxygen levels had less effect. An episode of size increase in two of the more extinction-resistant brachiopod species is unrelated to environmental change and possibly was the result of reduced interspecific competition for resources following the extinction of competitors. Based on the results of this study, predictions can be made for the possible responses of modern benthos to present-day environmental changes.

  17. Quality of life and anxiety in pregnancies after late pregnancy loss: a case-control study.

    PubMed

    Hunfeld, J A; Agterberg, G; Wladimiroff, J W; Passchier, J

    1996-09-01

    Pregnant women with (n = 24) and without (n = 26) a previous pregnancy loss (> 16 weeks) due to congenital anomalies were compared on quality of life and anxiety. Pregnant women with a previous loss were divided into those with and those without a normal livebirth since the loss [cases+ (n = 6) and cases- (n = 18), respectively]. Psychological measurements were carried out before and after an ultrasound scan in the second trimester of the pregnancy. Women with a previous loss who had not delivered a healthy infant between the loss and the present pregnancy showed a lower quality of life as revealed by feelings of social isolation, negative emotional reactions, and pain than the other groups. In addition, they showed more pregnancy-related anxiety. The negative emotions were particularly present just before the anomaly scan. Feelings of social isolation, negative emotional reactions, pain, and pregnancy-related anxiety were significantly positively related to trait anxiety, irrespective of having experienced late pregnancy loss. The implications of this study are that the referring gynaecologist, physician, or midwife should be aware of the strong emotions and major concerns of women in a pregnancy subsequent to a late pregnancy loss. In addition, they should offer these women the opportunity to express their emotional distress.

  18. Functional Connectivity in the Cognitive Control Network and the Default Mode Network in Late-life Depression

    PubMed Central

    Alexopoulos, George S.; Hoptman, Matthew J.; Kanellopoulos, Dora; Murphy, Christopher F.; Lim, Kelvin O.; Gunning, Faith M.

    2011-01-01

    Background Abnormalities have been identified in the Cognitive Control Network (CCN) and the default mode network (DMN) during episodes of late-life depression. This study examined whether functional connectivity at rest (FC) within these networks characterize late-life depression and predict antidepressant response. Methods 26 non-demented, non-MCI older adults were studied. Of these, 16 had major depression and 10 had no psychopathology. Depressed patients were treated with escitalopram (target dose 20 mg) for 12 weeks after a 2-week placebo phase. Resting state timeseries was determined prior to treatment. FC within the CCN was determined by placing seeds in the dACC and the DLPFC bilaterally. FC within the DMN was assessed from a seed placed in the posterior cingulate. Results Low resting state FC within the CCN and high FC within the DMN distinguished depressed from normal elderly subjects. Beyond this “double dissociation”, low resting state FC within the CCN predicted low remission rate and persistence of depressive symptoms and signs, apathy, and dysexecutive behavior after treatment with escitalopram. In contrast, resting state FC within the DMN was correlated with pessimism but did not predict treatment response. Conclusions If confirmed, these findings may serve as a signature of the brain’s functional topography characterizing late-life depression and sustaining its symptoms. By identifying the network abnormalities underlying biologically meaningful characteristics (apathy, dysexecutive behavior, pessimism) and sustaining late-life depression, these findings can provide a novel target on which new somatic and psychosocial treatments can be tested. PMID:22425432

  19. Climatic and tectonic controls on Late Triassic to Middle Jurassic sedimentation in northeastern Guangdong Province, South China

    NASA Astrophysics Data System (ADS)

    Pang, Chong-Jin; Li, Zheng-Xiang; Xu, Yi-Gang; Wen, Shu-Nv; Krapež, Bryan

    2016-05-01

    Stratigraphic analyses document climatic and tectonic controls on the filling of a Late Triassic to early Middle Jurassic (T3-J2) basin that developed on top of a young orogenic belt in southeastern South China. About 2700 m of Carnian to Bajocian sedimentary rocks is documented in the Meizhou region, Guangdong Province. The Carnian to Rhaetian sequence is characterized by deltaic facies that are succeeded by Hettangian fluvial, shallow marine and volcaniclastic facies, and by Sinemurian to early Toarcian interdistributary bay and floodplain facies. The late Toarcian to Bajocian sequence comprises proximal alluvial to lacustrine facies that changed upwards to fluvial facies. Fossil assemblages indicate that climatic conditions changed from tropical/subtropical warm humid, to temperate humid, and then to hot arid through the Late Triassic to the Middle Jurassic. Climatically induced changes (e.g., in precipitation, vegetation and erosion) exerted a strong influence on sediment supply, whereas tectonics played a dominant role in stratigraphic evolution, accommodation generation, sedimentation pattern and volcanism. Tectonostratigraphic analysis shows that the T3-J2 basin was initiated on an orogenic belt during late-stage orogeny, and evolved into shallow-marine and volcanic environments and then back to terrestrial facies during the post-orogenic stage. This was followed by regional uplift and the development of a basin-and-range province. The order of these events is similar to that of the central Rocky Mountains, western North America during the Palaeogene. The Mesozoic basin of South China and the Eocene basins of the central Rocky Mountains highlight the importance of subduction-related subsidence above young and broad orogens.

  20. Spider mites suppress tomato defenses downstream of jasmonate and salicylate independently of hormonal crosstalk

    PubMed Central

    Alba, Juan M; Schimmel, Bernardus C J; Glas, Joris J; Ataide, Livia M S; Pappas, Maria L; Villarroel, Carlos A; Schuurink, Robert C; Sabelis, Maurice W; Kant, Merijn R

    2015-01-01

    Plants respond to herbivory by mounting a defense. Some plant-eating spider mites (Tetranychus spp.) have adapted to plant defenses to maintain a high reproductive performance. From natural populations we selected three spider mite strains from two species, Tetranychus urticae and Tetranychus evansi, that can suppress plant defenses, using a fourth defense-inducing strain as a benchmark, to assess to which extent these strains suppress defenses differently. We characterized timing and magnitude of phytohormone accumulation and defense-gene expression, and determined if mites that cannot suppress defenses benefit from sharing a leaf with suppressors. The nonsuppressor strain induced a mixture of jasmonate- (JA) and salicylate (SA)-dependent defenses. Induced defense genes separated into three groups: ‘early’ (expression peak at 1 d postinfestation (dpi)); ‘intermediate’ (4 dpi); and ‘late’, whose expression increased until the leaf died. The T. evansi strains suppressed genes from all three groups, but the T. urticae strain only suppressed the late ones. Suppression occurred downstream of JA and SA accumulation, independently of the JA–SA antagonism, and was powerful enough to boost the reproductive performance of nonsuppressors up to 45%. Our results show that suppressing defenses not only brings benefits but, within herbivore communities, can also generate a considerable ecological cost when promoting the population growth of a competitor. PMID:25297722

  1. Methyl Jasmonate-Induced Lipidomic and Biochemical Alterations in the Intertidal Macroalga Gracilaria dura (Gracilariaceae, Rhodophyta)

    PubMed Central

    Kumari, Puja; Reddy, C.R.K.; Jha, Bhavanath

    2015-01-01

    The role of exogenously added methyl jasmonate (MeJA), a lipid-derived signaling compound, in inducing oxidative stress in the marine red macroalga Gracilaria dura was investigated. MeJA at a concentration of 1–100 µM was a strong stimulant of reactive oxygen species (H2O2, HO· and O2·−) (P < 0.05) causing considerable oxidative stress in G. dura. This further led to lipid peroxidation and degradation of the pigments Chl a and phycocyanin, with a concomitant increase in phycoerythrin. The MeJA-induced oxidative burst also led to the induction of a fatty acid oxidation cascade, resulting in the synthesis of hydroxy-oxylipins and the up-regulation of the 13-lipoxygenase pathway. Electrospray ionization-mass spectrometry-based shotgun lipidomic analysis revealed that monogalactosyldiacylglycerol (a chloroplastic glycerolipid) and phosphatidylcholine (extrachloroplastidic phopholipid) were the most affected lipid classes. The degradation of 18:3-fatty acid-containing monogalactosyldiacylglycerol inferred that it provided fatty acyl chains for the biosynthesis of 13-hydroperoxylinolenic acid, which was further directed towards either the jasmonate pathway or other alternative pathways of the fatty acid oxidation cascade, analogous to higher plants. Also, G. dura modulated the lipid acyl chains in such a way that no significant change was observed in the fatty acid profile of the treated thalli as compared with those of the control, except for C16:0, C16:1 (n-9), C20:3 (n-6) and C20:4 (n-6) (P < 0.05). Furthermore, MeJA caused the accumulation of phenolic compounds and the up-regulation of enzymes involved in secondary metabolism such as polyphenol oxidase, shikimate dehydrogenase and phenylalanine ammonia-lyase, indicating a shift towards secondary metabolism as a defense strategy to combat the induced oxidative stress. PMID:26276825

  2. Methyl Jasmonate-Induced Lipidomic and Biochemical Alterations in the Intertidal Macroalga Gracilaria dura (Gracilariaceae, Rhodophyta).

    PubMed

    Kumari, Puja; Reddy, C R K; Jha, Bhavanath

    2015-10-01

    The role of exogenously added methyl jasmonate (MeJA), a lipid-derived signaling compound, in inducing oxidative stress in the marine red macroalga Gracilaria dura was investigated. MeJA at a concentration of 1-100 µM was a strong stimulant of reactive oxygen species (H(2)O(2), HO· and O(2) (·-)) (P < 0.05) causing considerable oxidative stress in G. dura. This further led to lipid peroxidation and degradation of the pigments Chl a and phycocyanin, with a concomitant increase in phycoerythrin. The MeJA-induced oxidative burst also led to the induction of a fatty acid oxidation cascade, resulting in the synthesis of hydroxy-oxylipins and the up-regulation of the 13-lipoxygenase pathway. Electrospray ionization-mass spectrometry-based shotgun lipidomic analysis revealed that monogalactosyldiacylglycerol (a chloroplastic glycerolipid) and phosphatidylcholine (extrachloroplastidic phopholipid) were the most affected lipid classes. The degradation of 18:3-fatty acid-containing monogalactosyldiacylglycerol inferred that it provided fatty acyl chains for the biosynthesis of 13-hydroperoxylinolenic acid, which was further directed towards either the jasmonate pathway or other alternative pathways of the fatty acid oxidation cascade, analogous to higher plants. Also, G. dura modulated the lipid acyl chains in such a way that no significant change was observed in the fatty acid profile of the treated thalli as compared with those of the control, except for C16:0, C16:1 (n-9), C20:3 (n-6) and C20:4 (n-6) (P < 0.05). Furthermore, MeJA caused the accumulation of phenolic compounds and the up-regulation of enzymes involved in secondary metabolism such as polyphenol oxidase, shikimate dehydrogenase and phenylalanine ammonia-lyase, indicating a shift towards secondary metabolism as a defense strategy to combat the induced oxidative stress.

  3. Combined elicitation of methyl-jasmonate and red light on stilbene and anthocyanin biosynthesis.

    PubMed

    Tassoni, Annalisa; Durante, Lorenzo; Ferri, Maura

    2012-05-15

    Vitis vinifera cell suspensions are a suitable system to study the metabolic regulation of a large range of polyphenols, including flavonoids and stilbenes that play important roles in plant development. Grape cv. Barbera petioles cell cultures were treated with red light and 10 μM methyl-jasmonate (MeJA), alone or in combination, to investigate their influence and/or induction effect on the production of anthocyanins, catechins and free and mono-glucosylated stilbenes. The synthesis of total anthocyanins was slightly decreased by red light alone, while MeJA and MeJA plus red light increased the levels of these metabolites. When compared to the relative controls, the red light treatment decreased the amount of catechins and increased their release in the culture medium, while MeJA alone or in combination with red light increased their production. Red light treatment generally enhanced the amount of free and mono-glucosylated stilbenes during the entire observation period, as well as the percentage of their release in the media. Treatment with MeJA strongly promoted the production of total stilbenes, which was further elicited by the MeJA plus red light treatment. During the combined treatment, the presence of the light stimulus improved the effect of MeJA by anticipating the maximum increase of stilbenes which were also largely released (up to 90%). These results demonstrate that, in grapevine, as in other plant systems, the change of conditions in which the MeJA stimulus is perceived (e.g. going from total white to red light) drastically modifies the plant response to this hormone. The present paper confirms that the jasmonate transduction pathway is integrated into an elaborate signaling network that also comprehends the red light signaling pathway. Copyright © 2012 Elsevier GmbH. All rights reserved.

  4. Foliar application of methyl jasmonate induced physio-hormonal changes in Pisum sativum under diverse temperature regimes.

    PubMed

    Shahzad, Raheem; Waqas, Muhammad; Khan, Abdul Latif; Hamayun, Muhammad; Kang, Sang-Mo; Lee, In-Jung

    2015-11-01

    Global climate change brings with it unwarranted shifts in both abiotic (heat stress, cold stress, wind, precipitation) and biotic (pathogens, pests) environmental factors, thus posing a threat to agricultural productivity across the world. In plants, lodging due to storms or herbivory causes wounding stress and consequently enhances endogenous jasmonates. In response, the plant growth is arrested as plant defense is prioritized. We pre-treated pea plants with elevated methyl jasmonate (MeJA) levels i.e. 50 μM, 100 μM and 200 μM under controlled growth chamber conditions. The pre-treated plants were then kept at 40 °C (heat stress--HS), 4 °C (cold stress--CS) and 20 °C (optimum/control temperature--OT) for 72 h. The effect of such treatments on plant growth attributes, photosynthesis, stomatal conductance, cell death rate, and regulation of endogenous hormones were observed. Elevated MeJA application hindered plant growth attributes under HS, CS and OT conditions. Moreover, elevated MeJA levels lowered the rate of photosynthesis and stomatal conductance, induced stomatal closure, caused higher cells mortality in leaves under HS, CS, and OT conditions. Endogenous ABA contents significantly declined in all MeJA treatments under HS and OT, but increased under CS conditions. Exogenous MeJA enhanced endogenous jasmonic acid contents of pea plants, but altered endogenous salicylic acid contents under varying temperatures. Current study shows that higher concentrations of exogenous MeJA strengthen plant defense mechanism by hindering plant growth under stress conditions.

  5. Prosociality during the transition from late adolescence to young adulthood: the role of effortful control and ego-resiliency.

    PubMed

    Alessandri, Guido; Luengo Kanacri, Bernadette Paula; Eisenberg, Nancy; Zuffianò, Antonio; Milioni, Michela; Vecchione, Michele; Caprara, Gian Vittorio

    2014-11-01

    The present prospective study examined the prediction of prosociality from effortful control and ego-resiliency from late adolescence to emerging adulthood. Participants were 476 young adults (239 males and 237 females) with a mean age of 16 years (SD = .81) at T1, 18 years (SD = .83) at T2, 20 years (SD = .79) at T3, 22 years (SD = .81) at T4, and 26 years (SD = .81) at T5. Controlling for the stability of the examined variables and the effect of potential confounding variables (i.e., sex, socioeconomic status [SES], and age), results supported a model in which a temperamental dimension, effortful control, positively predicted a specific behavioral tendency (i.e., prosociality) indirectly through mediation by a personality factor (i.e., ego-resiliency). Practical implications of the results are discussed in terms of the importance of early prevention efforts designed to enhance the capacity to cope effectively with emotional reactions and difficult situations.

  6. Early programming of the oocyte epigenome temporally controls late prophase I transcription and chromatin remodelling

    PubMed Central

    Navarro-Costa, Paulo; McCarthy, Alicia; Prudêncio, Pedro; Greer, Christina; Guilgur, Leonardo G.; Becker, Jörg D.; Secombe, Julie; Rangan, Prashanth; Martinho, Rui G.

    2016-01-01

    Oocytes are arrested for long periods of time in the prophase of the first meiotic division (prophase I). As chromosome condensation poses significant constraints to gene expression, the mechanisms regulating transcriptional activity in the prophase I-arrested oocyte are still not entirely understood. We hypothesized that gene expression during the prophase I arrest is primarily epigenetically regulated. Here we comprehensively define the Drosophila female germ line epigenome throughout oogenesis and show that the oocyte has a unique, dynamic and remarkably diversified epigenome characterized by the presence of both euchromatic and heterochromatic marks. We observed that the perturbation of the oocyte's epigenome in early oogenesis, through depletion of the dKDM5 histone demethylase, results in the temporal deregulation of meiotic transcription and affects female fertility. Taken together, our results indicate that the early programming of the oocyte epigenome primes meiotic chromatin for subsequent functions in late prophase I. PMID:27507044

  7. Benefits of jasmonate-dependent defenses against vertebrate herbivores in nature

    PubMed Central

    Machado, Ricardo AR; McClure, Mark; Hervé, Maxime R; Baldwin, Ian T; Erb, Matthias

    2016-01-01

    Endogenous jasmonates are important regulators of plant defenses. If and how they enable plants to maintain their reproductive output when facing community-level herbivory under natural conditions, however, remains unknown. We demonstrate that jasmonate-deficient Nicotiana attenuata plants suffer more damage by arthropod and vertebrate herbivores than jasmonate-producing plants in nature. However, only damage by vertebrate herbivores translates into a significant reduction in flower production. Vertebrate stem peeling has the strongest negative impact on plant flower production. Stems are defended by jasmonate-dependent nicotine, and the native cottontail rabbit Sylvilagus nuttallii avoids jasmonate-producing N. attenuata shoots because of their high levels of nicotine. Thus, endogenous jasmonates enable plants to resist different types of herbivores in nature, and jasmonate-dependent defenses are important for plants to maintain their reproductive potential when facing vertebrate herbivory. Ecological and evolutionary models on plant defense signaling should aim at integrating arthropod and vertebrate herbivory at the community level. DOI: http://dx.doi.org/10.7554/eLife.13720.001 PMID:27352734

  8. Jasmonic acid involves in grape fruit ripening and resistant against Botrytis cinerea.

    PubMed

    Jia, Haifeng; Zhang, Cheng; Pervaiz, Tariq; Zhao, Pengcheng; Liu, Zhongjie; Wang, Baoju; Wang, Chen; Zhang, Lin; Fang, Jinggui; Qian, Jianpu

    2016-01-01

    Fruit ripening is a complex process that is regulated by a signal network. Whereas the regulatory mechanism of abscisic acid has been studied extensively in non-climacteric fruit, little is know about other signaling pathways involved in this process. In this study, we performed that plant hormone jasmonic acid plays an important role in grape fruit coloring and softening by increasing the transcription levels of several ripening-related genes, such as the color-related genes PAL1, DFR, CHI, F3H, GST, CHS, and UFGT; softening-related genes PG, PL, PE, Cell, EG1, and XTH1; and aroma-related genes Ecar, QR, and EGS. Lastly, the fruit anthocyanin, phenol, aroma, and cell wall materials were changed. Jasmonic acid positively regulated its biosynthesis pathway genes LOS, AOS, and 12-oxophytodienoate reductase (OPR) and signal pathway genes COI1 and JMT. RNA interference of grape jasmonic acid pathway gene VvAOS in strawberry fruit appeared fruit un-coloring phenotypes; exogenous jasmonic acid rescued this phenotypes. On the contrary, overexpression of grape jasmonic acid receptor VvCOI1 in the strawberry fruit accelerated the fruit-ripening process and induced some plant defense-related gene expression level. Furthermore, jasmonic acid treatment or strong jasmonic acid signal pathway in strawberry fruit make the fruit resistance against Botrytis cinerea.

  9. Interactive Effects of Jasmonic Acid, Salicylic Acid, and Gibberellin on Induction of Trichomes in Arabidopsis1

    PubMed Central

    Traw, M. Brian; Bergelson, Joy

    2003-01-01

    Leaf trichomes protect plants from attack by insect herbivores and are often induced following damage. Hormonal regulation of this plant induction response has not been previously studied. In a series of experiments, we addressed the effects of artificial damage, jasmonic acid, salicylic acid, and gibberellin on induction of trichomes in Arabidopsis. Artificial damage and jasmonic acid caused significant increases in trichome production of leaves. The jar1-1 mutant exhibited normal trichome induction following treatment with jasmonic acid, suggesting that adenylation of jasmonic acid is not necessary. Salicylic acid had a negative effect on trichome production and consistently reduced the effect of jasmonic acid, suggesting negative cross-talk between the jasmonate and salicylate-dependent defense pathways. Interestingly, the effect of salicylic acid persisted in the nim1-1 mutant, suggesting that the Npr1/Nim1 gene is not downstream of salicylic acid in the negative regulation of trichome production. Last, we found that gibberellin and jasmonic acid had a synergistic effect on the induction of trichomes, suggesting important interactions between these two compounds. PMID:14551332

  10. Did climatic seasonality control late Quaternary artiodactyl densities in western North America?

    NASA Astrophysics Data System (ADS)

    Broughton, Jack M.; Byers, David A.; Bryson, Reid A.; Eckerle, William; Madsen, David B.

    2008-10-01

    We develop and test a hypothesis here that the seasonality of temperature and precipitation played a major role in determining the population densities of artiodactyls (e.g., Ovis canadensis, Odocoileus hemionus, and Antilocapra americana) across the terminal Pleistocene and Holocene of western North America. For much of this region, general circulation climate models and a range of paleoclimatic data suggest that seasonal extremes in temperature peaked during the terminal Pleistocene and early Holocene and that early and middle Holocene precipitation followed a winter-wet, summer-dry pattern—conditions known to depress artiodactyl densities. These trends are mirrored in a northern Bonneville Basin macrophysical climate simulation model from which we derive terminal Pleistocene and Holocene climatic values and three indices of climatic seasonality: (1) intra-annual temperature range, (2) summer precipitation intensity, and (3) winter precipitation intensity. These indices are arrayed against three detailed late Quaternary artiodactyl abundance records in the Bonneville Basin: a unique paleontological record of fecal pellet densities, and archaeological records of artiodactyl skeletal elements and large game hunting tools. Each of these artiodactyl abundance records shows significant correlations with the model-derived seasonality indices and suggests that artiodactyls occurred in low densities from the terminal Pleistocene through the middle Holocene—substantial increases occurred during equable, summer-wet periods of the late Holocene. Archaeological vertebrate records from across western North America show very similar temporal patterns in artiodactyl abundances suggesting that the trend and its climate-based causes may be a very general one. These conclusions have far-reaching implications not only for our understanding of ancient human hunting and land use patterns, but for the future management of artiodactyls under scenarios of global warming that also

  11. Resveratrol and exercise to treat functional limitations in late life: design of a randomized controlled trial.

    PubMed

    Layne, Andrew S; Krehbiel, Lisa M; Mankowski, Robert T; Anton, Stephen D; Leeuwenburgh, Christiaan; Pahor, Marco; Sandesara, Bhanuprasad; Wu, Samuel S; Buford, Thomas W

    2017-06-01

    Skeletal muscle mitochondrial function declines with age and is a key factor in the maintenance of physical function among older adults. Research studies from animals and humans have consistently demonstrated that exercise improves skeletal muscle mitochondrial function in early and middle adulthood. However, mitochondrial adaptations to both acute and chronic exercise are attenuated in late life. Thus, there is an important need to identify adjuvant therapies capable of augmenting mitochondrial adaptations to exercise (e.g. improved mitochondrial respiration, muscle mitochondria biogenesis) among older adults. This study is investigating the potential of resveratrol supplementation for this purpose. The objective of this randomized, double-masked pilot trial is to evaluate the efficacy of resveratrol supplementation combined with a comprehensive supervised exercise program exercise for improving physical function among older adults. Moderately functioning, sedentary participants aged ≥60 years will perform 24 sessions (2 day/wk for 12 weeks) of center-based walking and resistance training and are randomly assigned to receive either (1) 500 mg/day resveratrol (2) 1000 mg/day resveratrol or (3) placebo. Study dependent outcomes include changes in 1) knee extensor strength, 2) objective measures of physical function (e.g. 4m walk test, Short Physical Performance Battery), 3) subjective measures of physical function assessed by Late Life Function and Disability Instrument, and 4) skeletal muscle mitochondrial function. This study will provide novel information regarding the therapeutic potential of resveratrol supplementation combined with exercise while also informing about the long-term clinical viability of the intervention by evaluating participant safety and willingness to engage in the intervention.

  12. New allocyclic dimensions in a prograding carbonate bank: Evidence for eustatic, tectonic, and paleoceanographic control (late Neogene, Bahamas)

    USGS Publications Warehouse

    Lidz, B.H.; McNeill, D.F.

    1997-01-01

    The deep-sea record, examined recently for the first time in a shallow-depocenter setting, has unveiled remarkable evidence for new sedimentary components and allocyclic complexity in a large, well-studied carbonate bank, the western Great Bahama Bank. The evidence is a composite foraminiferal signature - Paleocene to early Miocene (allogenic or reworked) and late Miocene to late Pliocene (host) planktic taxa, and redeposited middle Miocene shallow benthic faunas. Ages of the oldest and youngest planktic groups range from ??? 66 to ??? 2 Ma. The reworked and redeposited taxa are a proxy for significant sediment components that otherwise have no lithofacies or seismic resolution. The composite signature, reinforced by a distinctive distribution of the reworked and redeposited faunas, documents a much more complex late Neogene depositional system than previously known. The system is more than progradational. The source sequences that supplied the constituent bank-margin grains formed at different water depths and over hundreds of kilometers and tens of millions of years apart. New evidence from the literature and from data obtained during Ocean Drilling Program (OOP) Leg 166 in the Santaren Channel (Bahamas) support early interpretations based on the composite fossil record and provide valuable new dimensions to regional allocyclicity. The middle Miocene taxa were confined to the lower part of the section by the latest Miocene-earliest Pliocene(?) lowstand of sea level. An orderly occurrence of the allogenic taxa is unique to the global reworked geologic record and appears to have been controlled by a combination of Paleogene-early Neogene tectonics at the source, eustatic changes, and late Neogene current activity at the source and across the bank. The allogenic taxa expand the spatial and temporal range of information in the northern Bahamas by nearly an order of magnitude. In essence, some of the major processes active in the region during ??? 64 m.y. of the

  13. CYP94-mediated jasmonoyl-isoleucine hormone oxidation shapes jasmonate profiles and attenuates defence responses to Botrytis cinerea infection

    PubMed Central

    Aubert, Yann; Widemann, Emilie; Miesch, Laurence; Pinot, Franck; Heitz, Thierry

    2015-01-01

    Induced resistance to the necrotrophic pathogen Botrytis cinerea depends on jasmonate metabolism and signalling in Arabidopsis. We have presented here extensive jasmonate profiling in this pathosystem and investigated the impact of the recently reported jasmonoyl-isoleucine (JA-Ile) catabolic pathway mediated by cytochrome P450 (CYP94) enzymes. Using a series of mutant and overexpressing (OE) plant lines, we showed that CYP94B3 and CYP94C1 are integral components of the fungus-induced jasmonate metabolic pathway and control the abundance of oxidized conjugated but also some unconjugated derivatives, such as sulfated 12-HSO4-JA. Despite causing JA-Ile overaccumulation due to impaired oxidation, CYP94 deficiency had negligible impacts on resistance, associated with enhanced JAZ repressor transcript levels. In contrast, plants overexpressing (OE) CYP94B3 or CYP94C1 were enriched in 12-OH-JA-Ile or 12-COOH-JA-Ile respectively. This shift towards oxidized JA-Ile derivatives was concomitant with strongly impaired defence gene induction and reduced disease resistance. CYP94B3-OE, but unexpectedly not CYP94C1-OE, plants displayed reduced JA-Ile levels compared with the wild type, suggesting that increased susceptibility in CYP94C1-OE plants may result from changes in the hormone oxidation ratio rather than absolute changes in JA-Ile levels. Consistently, while feeding JA-Ile to seedlings triggered strong induction of JA pathway genes, induction was largely reduced or abolished after feeding with the CYP94 products 12-OH-JA-Ile and 12-COOH-JA-Ile, respectively. This trend paralleled in vitro pull-down assays where 12-COOH-JA-Ile was unable to promote COI1–JAZ9 co-receptor assembly. Our results highlight the dual function of CYP94B3/C1 in antimicrobial defence: by controlling hormone oxidation status for signal attenuation, these enzymes also define JA-Ile as a metabolic hub directing jasmonate profile complexity. PMID:25903915

  14. Autophagic degradation of dBruce controls DNA fragmentation in nurse cells during late Drosophila melanogaster oogenesis

    PubMed Central

    Shravage, Bhupendra V.; Sagona, Antonia P.; Lamark, Trond; Bjørkøy, Geir; Johansen, Terje; Rusten, Tor Erik; Brech, Andreas; Baehrecke, Eric H.

    2010-01-01

    Autophagy is an evolutionarily conserved pathway responsible for degradation of cytoplasmic material via the lysosome. Although autophagy has been reported to contribute to cell death, the underlying mechanisms remain largely unknown. In this study, we show that autophagy controls DNA fragmentation during late oogenesis in Drosophila melanogaster. Inhibition of autophagy by genetically removing the function of the autophagy genes atg1, atg13, and vps34 resulted in late stage egg chambers that contained persisting nurse cell nuclei without fragmented DNA and attenuation of caspase-3 cleavage. The Drosophila inhibitor of apoptosis (IAP) dBruce was found to colocalize with the autophagic marker GFP-Atg8a and accumulated in autophagy mutants. Nurse cells lacking Atg1 or Vps34 in addition to dBruce contained persisting nurse cell nuclei with fragmented DNA. This indicates that autophagic degradation of dBruce controls DNA fragmentation in nurse cells. Our results reveal autophagic degradation of an IAP as a novel mechanism of triggering cell death and thereby provide a mechanistic link between autophagy and cell death. PMID:20713604

  15. Ecofriendly control of potato late blight causative agent and the potential role of lactic acid bacteria: a review.

    PubMed

    Axel, Claudia; Zannini, Emanuele; Coffey, Aidan; Guo, Jiahui; Waters, Deborah M; Arendt, Elke K

    2012-10-01

    In times of increasing societal pressure to reduce the application of pesticides on crops, demands for environmentally friendly replacements have intensified. In the case of late blight, a devastating potato plant disease, the historically most widely known plant destroyer has been the oomycete Phytophthora infestans. To date, the most important strategy for control of this pathogen has been the frequent application of fungicides. Due to the aforementioned necessity to move away from traditional chemical treatments, many studies have focused on finding alternative ecofriendly biocontrol systems. In general, due to the different modes of actions (i.e. antagonistic effects or induction of plant defence mechanisms), the use of microorganisms as biological control agents has a definite potential. Amongst them, several species of lactic acid bacteria have been recognised as producers of bioactive metabolites which are functional against a broad spectrum of undesirable microorganisms, such as fungi, oomycetes and other bacteria. Thus, they may represent an interesting tool for the development of novel concepts in pest management. This review describes the present situation of late blight disease and summarises current literature regarding the biocontrol of the phytopathogen P. infestans using antagonistic microorganisms.

  16. The Jasmonate Pathway Is a Key Player in Systemically Induced Defense against Root Knot Nematodes in Rice1[C

    PubMed Central

    Nahar, Kamrun; Kyndt, Tina; De Vleesschauwer, David; Höfte, Monica; Gheysen, Godelieve

    2011-01-01

    Complex defense signaling pathways, controlled by different hormones, are involved in the reaction of plants to a wide range of biotic and abiotic stress factors. We studied the ability of salicylic acid, jasmonate (JA), and ethylene (ET) to induce systemic defense in rice (Oryza sativa) against the root knot nematode Meloidogyne graminicola. Exogenous ET (ethephon) and JA (methyl jasmonate) supply on the shoots induced a strong systemic defense response in the roots, exemplified by a major up-regulation of pathogenesis-related genes OsPR1a and OsPR1b, while the salicylic acid analog BTH (benzo-1,2,3-thiadiazole-7-carbothioic acid S-methyl ester) was a less potent systemic defense inducer from shoot to root. Experiments with JA biosynthesis mutants and ET-insensitive transgenics showed that ET-induced defense requires an intact JA pathway, while JA-induced defense was still functional when ET signaling was impaired. Pharmacological inhibition of JA and ET biosynthesis confirmed that JA biosynthesis is needed for ET-induced systemic defense, and quantitative real-time reverse transcription-polymerase chain reaction data revealed that ET application onto the shoots strongly activates JA biosynthesis and signaling genes in the roots. All data provided in this study point to the JA pathway to play a pivotal role in rice defense against root knot nematodes. The expression of defense-related genes was monitored in root galls caused by M. graminicola. Different analyzed defense genes were attenuated in root galls caused by the nematode at early time points after infection. However, when the exogenous defense inducers ethephon and methyl jasmonate were supplied to the plant, the nematode was less effective in counteracting root defense pathways, hence making the plant more resistant to nematode infection. PMID:21715672

  17. The late cretaceous Donlin Creek gold deposit, Southwestern Alaska: Controls on epizonal ore formation

    USGS Publications Warehouse

    Goldfarb, R.J.; Ayuso, R.; Miller, M.L.; Ebert, S.W.; Marsh, E.E.; Petsel, S.A.; Miller, L.D.; Bradley, D.; Johnson, Chad; McClelland, W.

    2004-01-01

    The Donlin Creek gold deposit, southwestern Alaska, has an indicated and inferred resource of approximately 25 million ounces (Moz) Au at a cutoff grade of 1.5 g/t. The ca. 70 Ma deposit is hosted in the Late Cretaceous Kuskokwim flysch basin, which developed in the back part of the are region of an active continental margin, on previously accreted oceanic terranes and continental fragments. A hypabyssal, mainly rhyolitic to rhyodacitic, and commonly porphyritic, 8- ?? 3-km dike complex, part of a regional ca. 77 to 58 Ma magmatic arc, formed a structurally competent host for the mineralization. This deposit is subdivided into about one dozen distinct prospects, most of which consist of dense quartz ?? carbonate veinlet networks that fill north-northeast-striking extensional fractures in the northeast-trending igneous rocks. The sulfide mineral assemblage is dominated by arsenopyrite, pyrite, and, typically younger, stibnite; gold is refractory within the arsenopyrite. Sericitization, carbonatization, and suffidation were the main alteration processes. Fluid inclusion studies of the quartz that hosts the resource indicate dominantly aqueous ore fluids with also about 3 to 7 mol percent CO2 ?? CH4 and a few tenths to a few mole percent NaCl + KCl. The gold-bearing fluids were mainly homogeneously trapped at approximately 275?? to 300??C and at depths of 1 to 2 km. Some of the younger stibnite may have been deposited by late-stage aqueous fluids at lower temperature. Measured ??18O values for the gold-bearing quartz range between 11 and 25 per mil; the estimated ??18O fluid values range from 7 to 12 per mil, suggesting a mainly crustally derived fluid. A broad range of measured ??D values for hydrothermal micas, between -150 and -80 per mil, is suggestive of a contribution from devolatilization of organic matter and/or minor amounts of mixing with meteoric fluids. Gold-associated hydrothermal sulfide minerals are characterized by ??34S values mainly between -16 and

  18. Sea Level and Paleoenvironment Control on Late Ordovician Source Rocks, Hudson Bay Basin, Canada

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Hefter, J.

    2009-05-01

    Hudson Bay Basin is one of the largest Paleozoic sedimentary basins in North America, with Southampton Island on its north margin. The lower part of the basin succession comprises approximately 180 to 300 m of Upper Ordovician strata including Bad Cache Rapids and Churchill River groups and Red Head Rapids Formation. These units mainly comprise carbonate rocks consisting of alternating fossiliferous limestone, evaporitic and reefal dolostone, and minor shale. Shale units containing extremely high TOC, and interpreted to have potential as petroleum source rocks, were found at three levels in the lower Red Head Rapids Formation on Southampton Island, and were also recognized in exploration wells from the Hudson Bay offshore area. A study of conodonts from 390 conodont-bearing samples from continuous cores and well cuttings from six exploration wells in the Hudson Bay Lowlands and offshore area (Comeault Province No. 1, Kaskattama Province No. 1, Pen Island No. 1, Walrus A-71, Polar Bear C-11 and Narwhal South O-58), and about 250 conodont-bearing samples collected from outcrops on Southampton Island allows recognition of three conodont zones in the Upper Ordovician sequence, namely (in ascendant sequence) Belodina confluens, Amorphognathus ordovicicus, and Rhipidognathus symmetricus zones. The three conodont zones suggest a cycle of sea level changes of rising, reaching the highest level, and then falling during the Late Ordovician. Three intervals of petroleum potential source rock are within the Rhipidognathus symmetricus Zone in Red Head Rapids Formation, and formed in a restricted anoxic and hypersaline condition during a period of sea level falling. This is supported by the following data: 1) The conodont Rhipidognathus symmetricus represents the shallowest Late Ordovician conodont biofacies and very shallow subtidal to intertidal and hypersaline condition. This species has the greatest richness within the three oil shale intervals to compare other parts of Red

  19. Phenotypic similarities between late-onset autosomal dominant and sporadic Alzheimer disease: A single-family case-control study

    PubMed Central

    Day, Gregory S; Musiek, Erik S; Roe, Catherine M; Norton, Joanne; Goate, Alison M; Cruchaga, Carlos; Cairns, Nigel J; Morris, John C

    2016-01-01

    Importance The “amyloid hypothesis” posits that disrupted amyloid-beta (Aβ) homeostasis initiates the pathological process resulting in Alzheimer disease (AD). Autosomal dominant Alzheimer disease (ADAD) has an early symptomatic onset and is caused by single gene mutations that result in overproduction of Aβ42. To the extent that “sporadic” late-onset Alzheimer disease (LOAD) also results from dysregulated Aβ42, the clinical phenotypes of ADAD and LOAD should be similar when controlling for the effects of age. Objective To use a family with late-onset ADAD caused by a presenilin 1 (PSEN1) mutation to mitigate the potential confound of age when comparing ADAD and LOAD. Design Case-control study of a family with late-onset ADAD and individuals with histopathologically-proven LOAD. Setting The Knight Alzheimer Disease Research Center, Washington University, St Louis, and other National Institutes of Aging-funded Alzheimer Disease Centers in the United States. Participants Ten PSEN1 A79V mutation carriers from multiple generations of a family with late-onset ADAD (median age-at-onset, 75.0 [63–77] years) and 12 noncarrier family members, followed at the Knight Alzheimer Disease Research Center (1985–2015); and 1115 individuals with neuropathologically confirmed LOAD (median age-at-onset, 74.0 [60–101] years) from the National Alzheimer Coordinating Center database (09/2005-12/14). Main Outcome and Measure Planned comparison of clinical characteristics between cohorts, including age at symptomatic onset, associated symptoms and signs, rates of progression, and disease duration. Results Seven (70%) mutation carriers developed AD dementia, while three are yet asymptomatic in their 7th and 8th decades of life. No differences were observed between mutation carriers and individuals with LOAD concerning age at symptomatic onset, presenting symptoms and duration, and rate of progression of dementia. Early emergence of comorbid hallucinations and delusions were

  20. A controlled study of light therapy in women with late luteal phase dysphoric disorder.

    PubMed

    Lam, R W; Carter, D; Misri, S; Kuan, A J; Yatham, L N; Zis, A P

    1999-06-30

    Previous studies suggest that light therapy, as used to treat seasonal affective disorder, may be beneficial for pre-menstrual depressive disorders. We conducted a six-menstrual cycle randomized, double-blind, counter-balanced, crossover study of dim vs. bright light therapy in women with late luteal phase dysphoric disorder (LLPDD). Fourteen women who met DSM-III-R criteria for LLPDD completed two menstrual cycles of prospective baseline monitoring of pre-menstrual symptoms, followed by two cycles of each treatment. During the 2-week luteal phase of each treatment cycle, patients were randomized to receive 30 min of evening light therapy using: (1) 10000 lx cool-white fluorescent light (active condition); or (2) 500 lx red fluorescent light (placebo condition), administered by a light box at their homes. After two menstrual cycles of treatment, patients were immediately crossed over to the other condition for another two cycles. Outcome measures were assessed at the mid-follicular and luteal phases of each cycle. Results showed that the active bright white light condition significantly reduced depression and pre-menstrual tension scores during the symptomatic luteal phase, compared to baseline, while the placebo dim red light condition did not. These results suggest that bright light therapy is an effective treatment for LLPDD.

  1. Magnetic Properties of Bermuda Rise Sediments Controlled by Glacial Cycles During the Late Pleistocene

    NASA Astrophysics Data System (ADS)

    Roud, S.

    2015-12-01

    Sediments from ODP site 1063 (Bermuda Rise, North Atlantic) contain a high-resolution record of geomagnetic field behavior during the Brunhes Chron. We present rock magnetic data of the upper 160 mcd (<900 ka) from hole 1063D that show magnetic properties vary in concert with glacial cycles. Magnetite appears to be the main magnetic carrier in the carbonate-dominated interglacial horizons, yet exhibits contrasting grain size distributions depending on the redox state of the horizons. Higher contributions of single domain magnetite exist above the present day sulfate reduction zone (ca. 44 mcd) with relatively higher multidomain magnetite components below that likely arise from the partial dissolution of SD magnetite in the deeper, anoxic horizons. Glacial horizons on the other hand, characterized by enhanced terrigenous deposition, show no evidence for diagenetic dissolution but do indicate the presence of authigenic greigite close to glacial maxima (acquisition of gyro-remanence, strong magnetostatic interactions and SD properties). Glacial horizons contain hematite (maxima in HIRM and S-Ratio consistent with a reddish hue) and exhibit higher ARM anisotropy and pronounced sedimentary fabrics. We infer that post depositional processes affected the magnetic grain size and mineralogy of Bermuda rise sediments deposited during the late Pleistocene. Hematite concentration is interpreted to reflect primary terrigenous input that is likely derived from the Canadian Maritime Provinces. A close correlation between HIRM and magnetic foliation suggests that changes in sediment composition (terrigenous vs. marine biogenic) were accompanied by changes in the depositional processes at the site.

  2. A Galpha subunit controls zoospore motility and virulence in the potato late blight pathogen Phytophthora infestans.

    PubMed

    Latijnhouwers, Maita; Ligterink, Wilco; Vleeshouwers, Vivianne G A A; van West, Pieter; Govers, Francine

    2004-02-01

    The heterotrimeric G-protein pathway is a ubiquitous eukaryotic signalling module that is known to regulate growth and differentiation in many plant pathogens. We previously identified Pigpa1, a gene encoding a G-protein alpha subunit from the potato late blight pathogen Phytophthora infestans. P. infestans belongs to the class oomycetes, a group of organisms in which signal transduction processes have not yet been studied at the molecular level. To elucidate the function of Pigpa1, PiGPA1-deficient mutants were obtained by homology-dependent gene silencing. The Pigpa1-silenced mutants produced zoospores that turned six to eight times more frequently, causing them to swim only short distances compared with wild type. Attraction to the surface, a phenomenon known as negative geotaxis, was impaired in the mutant zoospores, as well as autoaggregation and chemotaxis towards glutamic and aspartic acid. Zoospore production was reduced by 20-45% in different Pigpa1-silenced mutants. Transformants expressing constitutively active forms of PiGPA1, containing amino acid substitutions (R177H and Q203L), showed no obvious phenotypic differences from the wild-type strain. Infection efficiencies on potato leaves ranged from 3% to 14% in the Pigpa1-silenced mutants, compared with 77% in wild type, showing that virulence is severely impaired. The results prove that PiGPA1 is crucial for zoospore motility and for pathogenicity in an important oomycete plant pathogen.

  3. Controls on deposition of the St. Peter Sandstone (Middle-Late Ordovician), Michigan basin

    SciTech Connect

    Nadon, G.C.; Simo, A.; Byers, C.W.; Dott, R.H, Jr. )

    1991-08-01

    The St. Peter Sandstone (Middle-late Ordovician) of the Michigan basin represents an approximately 10-m.y. interval of clastic deposition in an otherwise carbonate-dominated Ordovician succession. This interval, up to 320 m thick, also coincides with a change in basin configuration from the nearly circular depocenter of the underlying Shakopee Formation to an east-west elongate trough situated west to Saginaw Bay. Interpretation of well logs and core from throughout the basin indicates that the clastics are composed of 20-25 sequences upper shoreface to tidal-flat environments. The sequences are interbedded with heavily bioturbated, shaly, lower shoreface sandstones (1-14 m thick) and, in the central and southeastern parts of the basin, with carbonate shales, stromatolites, and oolitic grain-stones (2-39 m thick). The eastern and southeastern margins of the basin contain the thickest carbonate accumulations. Hydrocarbons fields are located over structural highs formed by reactivation of basement structures. Detailed comparison of well logs within field shows that sedimentary cycles thin over the structures as a result of the local reduction in the formation of accommodation space by syndepositional movements on the faults. The presence of thick carbonates along the southeastern margin of the basin is a result of the combination of distance form the clastic source and the episodic formation of accommodation space by syndepositional normal faulting along the basin margin.

  4. Easy Preparation of Methyl 7-epi-Jasmonate and Four Stereoisomers of Methyl Cucurbate, and Assessment of the Stereogenic Effect of Jasmonate on Phytohormonal Activities.

    PubMed

    Seto, H; Nomura, E; Fujioka, S; Koshino, H; Suenaga, T; Yoshida, S

    1999-01-01

    To test the stereogenic effect of jasmonate on phytohormonal activities, methyl 7-epi-jasmonate (1b) and four stereoisomers of methyl cucurbate were easily prepared in racemic form: epimerization at the C-7 position of a commercially available methyl jasmonate (2b) with a base and subsequent fractional distillation gave a 46:54 mixture of 1b and 2b, whose reduction gave a mixture of methyl cucurbates (3-6). This synthetic chemistry was supplemented by molecular modeling and an NMR study on 1b and 2b. An assessment of the inhibitory activities of the prepared jasmonates on growth of the second leaf sheath of rice and on seed germination of cress clarified that the cis-configuration of the C-3 and C-7 side chains of jasmonate was an important factor for the high activities. In inhibiting the seed germination of cress, methyl 6-epi-cucurbate (4) exhibited activity that was markedly higher than the other compounds tested, showing that the stereochemistry at C-6 as well as at C-3 and C-7 was strictly recognized by this bioassay.

  5. Jasmonate signaling in the field, part II: insect-guided characterization of genetic variations in jasmonate-dependent defenses of transgenic and natural Nicotiana attenuata populations.

    PubMed

    Gaquerel, Emmanuel; Stitz, Michael; Kallenbach, Mario; Baldwin, Ian T

    2013-01-01

    The introduction of genetically modified plants into natural habitats represents a valuable means to determine organismic level functions of a gene and its effects on a plant's interaction with other organisms. Nicotiana attenuata, a wild tobacco species native of the southwestern USA that grows in the immediate postfire environment, is one of the important host plants for herbivore populations recolonizing recently burned habitats in the Great Basin Desert. Here, we provide detailed guidelines for the analysis, under field conditions, of jasmonate-dependent defense and its impact on the plant's native herbivore community. The procedures are based on the field release of transgenic lines silenced for jasmonate biogenesis, metabolism, or perception to conduct association studies between defense trait expression (secondary metabolite and trypsin proteinase inhibitor accumulation) and insect infestations. Additionally, because some insects have evolved mechanisms to "eavesdrop" on jasmonate signaling when selecting their host plants, we describe how leafhoppers of the species Empoasca, which selectively colonize jasmonate-deficient plants, can be used as "bloodhounds" for identifying natural variations in jasmonate signaling among natural N. attenuata populations.

  6. Yeast two-hybrid analysis of jasmonate signaling proteins.

    PubMed

    Cuéllar, Amparo Pérez; Pauwels, Laurens; De Clercq, Rebecca; Goossens, Alain

    2013-01-01

    Protein-protein interaction studies are crucial to unravel how jasmonate (JA) signals are transduced. Among the different techniques available, yeast two-hybrid (Y2H) is commonly used within the JA research community to identify proteins belonging to the core JA signaling module. The technique is based on the reconstitution of a transcriptional activator that drives the reporter gene expression upon protein-protein interactions. The method is sensitive and straightforward and can be adapted for different approaches. In this chapter, we provide a detailed protocol to perform targeted Y2H assays to test known proteins and/or protein domains for direct interaction in a pairwise manner and present the possibility to study ternary protein complexes through Y3H.

  7. A randomized controlled trial of coenzyme Q10 for fatigue in the late-onset sequelae of poliomyelitis.

    PubMed

    Peel, Margaret M; Cooke, Marie; Lewis-Peel, Helen J; Lea, Rodney A; Moyle, Wendy

    2015-12-01

    To determine if coenzyme Q(10) alleviates fatigue in the late-onset sequelae of poliomyelitis. Parallel-group, randomized, placebo-controlled trial. Coenzyme Q(10) has been shown to boost muscle energy metabolism in post-polio subjects but it does not promote muscle strength, endurance or function in polio survivors with post-poliomyelitis syndrome. However, the collective increased energy metabolism might contribute to a reduction in post-polio fatigue. Polio survivors from the Australian post-polio networks in Queensland and New South Wales who attribute a moderate to high level of fatigue to their diagnosed late-onset sequelae of poliomyelitis. Those with fatigue-associated comorbidities of diabetes, anaemia, hypothyroidism and fibromyalgia were excluded. Participants were assigned (1:1), with stratification of those who use energy-saving mobility aids, to receive 100 mg coenzyme Q(10) or matching placebo daily for 60 days. Participants and investigators were blinded to group allocation. Fatigue was assessed by the Multidimensional Assessment of Fatigue as the primary outcome and the Fatigue Severity Scale as secondary outcome. Of 103 participants, 54 were assigned to receive coenzyme Q(10) and 49 to receive the placebo. The difference in the mean score reductions between the two groups was not statistically significant for either fatigue measure. Oral supplementation with coenzyme Q(10) was safe and well-tolerated. A daily dose of 100 mg coenzyme Q(10) for 60 days does not alleviate the fatigue of the late-onset sequelae of poliomyelitis. The registration number for the clinical trial is ACTRN 12612000552886. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Hadley circulation and precipitation changes controling black shale deposition in the Late Jurassic Boreal Seaway

    NASA Astrophysics Data System (ADS)

    Armstrong, Howard A.; Wagner, Thomas; Herringshaw, Liam G.; Farnsworth, Alexander J.; Lunt, Daniel J.; Harland, Melise; Imber, Jonathan; Loptson, Claire; Atar, Elizabeth F. L.

    2016-08-01

    New climate simulations using the HadCM3L model with a paleogeography of the Late Jurassic (155.5 Ma) and proxy-data corroborate that warm and wet tropical-like conditions reached as far north as the UK sector of the Jurassic Boreal Seaway (~35°N). This is associated with a northern hemisphere Jurassic Hadley cell and an intensified subtropical jet which both extend significantly poleward than in the modern (July-September). Deposition of the Kimmeridge Clay Formation (KCF) occurred in the shallow, storm-dominated, epeiric Boreal Seaway. High-resolution paleo-environmental proxy data from the Kimmeridge Clay Formation (KCF; ~155-150 Ma), UK, are used to test for the role of tropical atmospheric circulation on meter-scale heterogeneities in black shale deposition. Proxy and model data show that the most organic-rich section (eudoxus to mid-hudlestoni zones) is characterized by a positive δ13Corg excursion and up to 37 wt % total organic carbon (%TOC). Orbital modulation of organic carbon burial primarily in the long eccentricity power band combined with a clear positive correlation between %TOC carbonate-free and the kaolinite/illite ratio supports peak organic carbon burial under the influence of very humid climate conditions, similar to the modern tropics. This reinterpretation of large-scale climate relationships, supported by independent modeling and geological data, has profound implications for atmospheric circulation patterns and processes affecting marine productivity and organic carbon burial further north along the Boreal Seaway, including the Arctic.

  9. Differences in trunk control between early and late pregnancy during gait.

    PubMed

    Sawa, Ryuichi; Doi, Takehiko; Asai, Tsuyoshi; Watanabe, Kaori; Taniguchi, Takeshi; Ono, Rei

    2015-10-01

    The aim of this study was to compare gait characteristics, including the functional ability of the trunk, between women before and during the third trimester of pregnancy. Gait measurements were performed on 27 pregnant women, who were divided into two groups using the threshold of 28 gestational weeks. The subjects were instructed to walk at their preferred speed. In addition to stride-time coefficient of variation, root mean square (RMS) and autocorrelation coefficient, coefficient of attenuation (CoA) of acceleration was computed as an index to assess the functional ability of the trunk. Differences of gait characteristics between the groups were determined by the Mann-Whitney U test. Gait characteristics that showed a significant difference between the groups were further analyzed with adjustment by age, height, weight and gait velocity by using multiple regression analysis. Women during the third trimester of pregnancy showed significantly smaller RMS in the anteroposterior direction at the lower trunk than those before the third trimester of pregnancy, even after adjusting for age, height, weight and gait velocity [β=0.47; 95% confidence interval (CI) 0.07-0.25]. CoA in the anteroposterior direction was also significantly lower in women during the third trimester of pregnancy than in those before the third trimester of pregnancy after adjustment by age, height, weight and gait velocity (β=0.44; 95% CI 0.39-18.52). The present cross-sectional study suggests the possibility that the functional ability of the trunk during gait declines in late pregnancy. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Reprint of: Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica

    NASA Astrophysics Data System (ADS)

    Aitken, Alan R. A.; Wilson, Gary S.; Jordan, Tom; Tinto, Kirsty; Blakemore, Hamish

    2012-10-01

    The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important to investigate the lithosphere's flexural properties, and estimate their influence on basin architecture and evolution. Seismic and gravity data are used to constrain 3D forward modelling of the progressive development of accommodation space within the flexural basins. Elastic plate flexure was calculated for a range of effective elastic thicknesses (Te) from 0.5 to 25 km using a spectral method. Models with low, but nonzero, Te values (2 km < Te < 5 km) produce the best fit to the gravity data, although uncertainty is high due to inaccuracies in the Digital Elevation Model. The slopes of flexural horizons revealed in seismic reflection lines are consistent with this, indicating a Te of 2 km to 5 km, although the depths to these horizons are not consistent, perhaps due to a northwards slope, or step, in the pre-flexural surface. These results indicate that the lithospheric strength of southern McMurdo Sound is significantly less than estimates of the regional average (Te ~ 20 km). This low strength may reflect the weakening effects of the Terror Rift, and perhaps also the Discovery Accommodation Zone, a region of major transverse faulting. A low Te model (Te = 3) for southern McMurdo Sound predicts the development of two discrete flexural depressions, each 2-2.5 km deep. The predicted stratigraphy of the northern basin reflects flexure due to Ross Island, predominantly erupted since ca. 1.8 Ma. The predicted stratigraphy of the southern basin reflects more gradual flexure from ca. 10 Ma to ca. 2 Ma, due to the more dispersed volcanoes of the Discovery subprovince. Collectively, these two basins have the potential to preserve a remarkable stratigraphic record of Antarctic climate change through the late Neogene.

  11. Late Quaternary intensified monsoon phases control landscape evolution in the northwest Himalaya

    NASA Astrophysics Data System (ADS)

    Bookhagen, Bodo; Thiede, Rasmus C.; Strecker, Manfred R.

    2005-02-01

    The intensity of the Asian summer-monsoon circulation varies over decadal to millennial time scales and is reflected in changes in surface processes, terrestrial environments, and marine sediment records. However, the mechanisms of long-lived (2 5 k.y.) intensified monsoon phases, the related changes in precipitation distribution, and their effect on landscape evolution and sedimentation rates are not yet well understood. The arid high-elevation sectors of the orogen correspond to a climatically sensitive zone that currently receives rain only during abnormal (i.e., strengthened) monsoon seasons. Analogous to present-day rainfall anomalies, enhanced precipitation during an intensified monsoon phase is expected to have penetrated far into these geomorphic threshold regions where hillslopes are close to the angle of failure. We associate landslide triggering during intensified monsoon phases with enhanced precipitation, discharge, and sediment flux leading to an increase in pore-water pressure, lateral scouring of rivers, and oversteepening of hillslopes, eventually resulting in failure of slopes and exceptionally large mass movements. Here we use lacustrine deposits related to spatially and temporally clustered large landslides (>0.5 km3) in the Sutlej Valley region of the northwest Himalaya to calculate sedimentation rates and to infer rainfall patterns during late Pleistocene (29 24 ka) and Holocene (10 4 ka) intensified monsoon phases. Compared to present-day sediment-flux measurements, a fivefold increase in sediment-transport rates recorded by sediments in landslide-dammed lakes characterized these episodes of high climatic variability. These changes thus emphasize the pronounced imprint of millennial-scale climate change on surface processes and landscape evolution.

  12. Flexural controls on late Neogene basin evolution in southern McMurdo Sound, Antarctica

    NASA Astrophysics Data System (ADS)

    Aitken, Alan R. A.; Wilson, Gary S.; Jordan, Thomas; Tinto, Kirsty; Blakemore, Hamish

    2012-01-01

    The basins of southern McMurdo Sound have evolved under the influence of lithospheric flexure induced by the loads of the Erebus Volcanic Province. To characterise these basins, it is important to investigate the lithosphere's flexural properties, and estimate their influence on basin architecture and evolution. Seismic and gravity data are used to constrain 3D forward modelling of the progressive development of accommodation space within the flexural basins. Elastic plate flexure was calculated for a range of effective elastic thicknesses (T e) from 0.5 to 25 km using a spectral method. Models with low, but nonzero, T e values (2 km < T e < 5 km) produce the best fit to the gravity data, although uncertainty is high due to inaccuracies in the Digital Elevation Model. The slopes of flexural horizons revealed in seismic reflection lines are consistent with this, indicating a T e of 2 km to 5 km, although the depths to these horizons are not consistent, perhaps due to a northwards slope, or step, in the pre-flexural surface. These results indicate that the lithospheric strength of southern McMurdo Sound is significantly less than estimates of the regional average (T e ~ 20 km). This low strength may reflect the weakening effects of the Terror Rift, and perhaps also the Discovery Accommodation Zone, a region of major transverse faulting. A low T e model (T e = 3) for southern McMurdo Sound predicts the development of two discrete flexural depressions, each 2-2.5 km deep. The predicted stratigraphy of the northern basin reflects flexure due to Ross Island, predominantly erupted since ca. 1.8 Ma. The predicted stratigraphy of the southern basin reflects more gradual flexure from ca. 10 Ma to ca. 2 Ma, due to the more dispersed volcanoes of the Discovery subprovince. Collectively, these two basins have the potential to preserve a remarkable stratigraphic record of Antarctic climate change through the late Neogene.

  13. Plant growth hormones suppress the development of Harpophora maydis, the cause of late wilt in maize.

    PubMed

    Degani, Ofir; Drori, Ran; Goldblat, Yuval

    2015-01-01

    Late wilt, a severe vascular disease of maize caused by the fungus Harpophora maydis, is characterized by rapid wilting of maize plants before tasseling and until shortly before maturity. The pathogen is currently controlled by resistant maize cultivars, but the disease is constantly spreading to new areas. The plant's late phenological stage at which the disease appears suggests that plant hormones may be involved in the pathogenesis. This work revealed that plant growth hormones, auxin (Indole-3-acetic acid) and cytokinin (kinetin), suppress H. maydis in culture media and in a detached root assay. Kinetin, and even more auxin, caused significant suppression of fungus spore germination. Gibberellic acid did not alter colony growth rate but had a signal suppressive effect on the pathogens' spore germination. In comparison, ethylene and jasmonic acid, plant senescing and defense response regulators, had minor effects on colony growth and spore germination rate. Their associate hormone, salicylic acid, had a moderate suppressive effect on spore germination and colony growth rate, and a strong influence when combined with auxin. Despite the anti-fungal auxin success in vitro, field experiments with dimethylamine salt of  2,4-dichlorophenoxyacetic acid (that mimics the influence of auxin) failed to suppress the late wilt. The lines of evidence presented here reveal the suppressive influence of the three growth hormones studied on fungal development and are important to encourage further and more in-depth examinations of this intriguing hormonal complex regulatory and its role in the maize-H. maydis interactions.

  14. [The Impact of Late Umbilical Cord Clamping on Neonatal Jaundice and Postpartum Hemorrhage: A Randomized Controlled Trail].

    PubMed

    Chien, Pei-Chun; Yang, Cherng-Chia; Gau, Meei-Ling; Liu, Chieh-Yu; Lee, Tzu-Ying

    2015-08-01

    The current evidence supports the clinical benefits of late umbilical cord clamping. These benefits include increased blood volume and total body iron. Furthermore, delayed cord clamping facilitates the transplantation of stem cells, which helps the development of infant bodily systems. However, due to concerns related to postpartum hemorrhaging and neonate jaundice, most maternity units still clamp the cord immediately after a child is born. This study investigates the impact of delaying cord clamping on neonatal jaundice and postpartum hemorrhage. A randomized, controlled trial was conducted at a regional teaching hospital in northern Taiwan. One hundred and five healthy nulliparous women at 36 weeks of pregnancy were included and allocated randomly to the experiment group (n=44) and the control group (n=61). Participants in the experiment group received delayed cord clamping (DCC) at 3 minutes after delivery. Participants in the control group received early cord clamping (ECC) at around 1 minute after delivery. Clinical measures of the outcomes were measured by the infant transcutaneous bilirubin levels (TcB) and postpartum hemorrhage at birth. A structured questionnaire and biophysical measures were used to collect data on participant demographics, obstetrical information, maternal blood loss at birth, neonate weight and TcB level at hospitalization, and whether or not the infant received phototherapy at 4-7 days postpartum. Overall, there was no significant difference between the two groups in terms of neonatal jaundice, maternal hemorrhage at birth, and phototherapy rates at time of hospitalization and at 4-7 days postpartum. The findings of the present study support that late umbilical cord clamping does not increase the risk of maternal postpartum hemorrhaging or neonate jaundice. Thus, we suggest that clinicians inform clients during prenatal classes of the benefits of delayed cord clamping and also use current, evidence-based knowledge to dispel client

  15. Eustatic and climatic control on the Upper Muschelkalk Sea (late Anisian/Ladinian) in the Central European Basin

    NASA Astrophysics Data System (ADS)

    Franz, M.; Kaiser, S. I.; Fischer, J.; Heunisch, C.; Kustatscher, E.; Luppold, F. W.; Berner, U.; Röhling, H.-G.

    2015-12-01

    The Upper Muschelkalk in the Central European Basin (CEB) is a key example of eustatic and climatic controls on inland seas. The late Anisian rapid transgression from Tethyan waters culminated in a large semi-enclosed inland sea stretching across the CEB. Subsequently, the slow but successive retreat in the early Ladinian resulted in a small remnant sea. The pronounced stratal pattern architectures are translated into a framework of 3rd- and 4th-order T-R sequences. The latest Illyrian 3rd-order maximum flooding surface corresponds to maximum abundances of carbonates and marine phytoplankton. An euryhaline marine ecology is indicated by prasinophycean algae dominating over acritarchs and δ18OP values of 18.9-22.4‰ VSMOW corresponding to Tethyan references. During the 3rd-order regressive phase successive freshening up to hyposaline conditions is indicated by up to 3‰ depleted δ18OP values, shifts to more radiogenic 87Sr/86Sr ratios and maximum abundances of terrestrial palynomorphs. Likewise, 4th-order T-R sequences are constrained by commutated stratal pattern architectures, palynofacies and geochemistry. The favourable correlation of middle Triassic 3rd-order sequences of Tethyan and peri-Tethyan basins demonstrate the principle control of circum-Tethyan eustatic cycles. 4th-order sequences are evident and, although not yet correlatable in detail, indicate 106-year scale eustatic cycles which may be attributed to glacioeustatic sea-level changes. The subordinated control of arid to semiarid low latitude and semihumid to humid temperate mid latitude climates affected the Upper Muschelkalk Sea in particular during 4th-order sea-level lowstands. Substantial fresh water input from Scandinavian sources caused temporal stratification leading to stagnant bottom waters and/or sediments as indicated by palynofacies and U/Th and Ni/Co redox indices. The herein reconstructed middle Triassic zonal climates are in agreement to previously published Late Triassic zonal

  16. Biomass, production, and control of heterotrophic bacterioplankton during a late phytoplankton bloom in the Amundsen Sea Polynya, Antarctica

    NASA Astrophysics Data System (ADS)

    Hyun, Jung-Ho; Kim, Sung-Han; Yang, Eun Jin; Choi, Ayeon; Lee, Sang Hoon

    2016-01-01

    We investigated the heterotrophic bacterial biomass and production in February 2012, in four habitats (a polynya, sea-ice zone, ice shelf, and the open sea) in the Amundsen Sea to determine the spatial distribution, controlling factors, and ecological role of the bacteria during a late phytoplankton bloom by Phaeocystis antarctica. Bacterial abundance (BA) and production (BP) were highest at the center of the polynya, and both were significantly correlated with phytoplankton biomass. BP accounted for average 17% of the organic carbon produced by phytoplankton primary production (PP), which is higher than the average BP:PP ratio reported in most open ocean. The abundance of heterotrophic nanoflagellates (HNF) was correlated with the BA, and the average bacteria:HNF ratio (260) was lower than the values reported in most marine environments (400-1000), including the Ross Sea Polynya (800). Evidence for a tight coupling of bacteria and phytoplankton activities on the one hand and intense HNF grazing on bacteria on the other could be found in the high BP:PP and low bacteria:HNF ratios, respectively. Interestingly, these data were accompanied by low particulate carbon export fluxes measured during the late Phaeocystis bloom. Together, these results indicated that the microbial loop plays a significant role in the biogeochemical carbon cycle and food web processes in the Amundsen Sea Polynya.

  17. Controls on late Paleozoic and early Mesozoic eolian deposition of the western United States

    NASA Astrophysics Data System (ADS)

    Marzolf, John E.

    1988-04-01

    terrestrial sediments. Mesozoic eolian sandstones of the western interior are Type II with distal source in the Gulf of Mexico-Atlantic rift belts. Erg development was initiated by marine regression and terminated by marine transgression. The late Paleozoic eolian sandstones of the western United States are a combination of Type I and II with proximal source in the Ancestral Rockies.

  18. Functional characterization of a novel jasmonate ZIM-domain interactor (NINJA) from upland cotton (Gossypium hirsutum).

    PubMed

    Wang, Le; Wu, Shu-Ming; Zhu, Yue; Fan, Qiang; Zhang, Zhen-Nan; Hu, Guang; Peng, Qing-Zhong; Wu, Jia-He

    2017-03-01

    The jasmonic acid (JA) signalling pathway plays roles in plant development and defence against biotic and abiotic stresses. We isolated a cotton NINJA (novel interactor of JA ZIM-domain) gene, designated GhNINJA, which contains a 1305 bp open read frame. The GhNINJA gene encodes a 434 amino acid peptide. According to quantitative real-time PCR analysis, GhNINJA is preferentially expressed in roots, and its expression level is greatly induced by Verticillium dahliae infection. Through a virus-induced gene silencing technique, we developed GhNINJA-silenced cotton plants, which had significantly decreased expression of the target gene with an average expression of 6% of the control. The regenerating lateral root growth of silenced plants was largely inhibited compared to the control. Analysis by microscopy demonstrated that the cell length of the root differentiation zone in GhNINJA-silenced plants is significantly shorter than those of the control. Moreover, the silenced plants exhibited higher tolerance to V. dahliae infection compared to the control, which was linked to the increased expression of the defence marker genes PDF1.2 and PR4. Together, these data indicated that knockdown of GhNINJA represses the root growth and enhances the tolerance to V. dahliae. Therefore, GhNINJA gene can be used as a candidate gene to breed the new cultivars for improving cotton yield and disease resistance. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. Jasmonic acid-induced changes in Brassica oleracea affect oviposition preference of two specialist herbivores.

    PubMed

    Bruinsma, Maaike; Van Dam, Nicole M; Van Loon, Joop J A; Dicke, Marcel

    2007-04-01

    Jasmonic acid (JA) is a key hormone involved in plant defense responses. The effect of JA treatment of cabbage plants on their acceptability for oviposition by two species of cabbage white butterflies, Pieris rapae and P. brassicae, was investigated. Both butterfly species laid fewer eggs on leaves of JA-treated plants compared to control plants. We show that this is due to processes in the plant after JA treatment rather than an effect of JA itself. The oviposition preference for control plants is adaptive, as development time from larval hatch until pupation of P. rapae caterpillars was longer on JA-treated plants. Total glucosinolate content in leaf surface extracts was similar for control and treated plants; however, two of the five glucosinolates were present in lower amounts in leaf surface extracts of JA-treated plants. When the butterflies were offered a choice between the purified glucosinolate fraction isolated from leaf surface extracts of JA-treated plants and that from control plants, they did not discriminate. Changes in leaf surface glucosinolate profile, therefore, do not seem to explain the change in oviposition preference of the butterflies after JA treatment, suggesting that as yet unknown infochemicals are involved.

  20. Arabidopsis JASMONATE-INDUCED OXYGENASES down-regulate plant immunity by hydroxylation and inactivation of the hormone jasmonic acid.

    PubMed

    Caarls, Lotte; Elberse, Joyce; Awwanah, Mo; Ludwig, Nora R; de Vries, Michel; Zeilmaker, Tieme; Van Wees, Saskia C M; Schuurink, Robert C; Van den Ackerveken, Guido

    2017-06-13

    The phytohormone jasmonic acid (JA) is vital in plant defense and development. Although biosynthesis of JA and activation of JA-responsive gene expression by the bioactive form JA-isoleucine have been well-studied, knowledge on JA metabolism is incomplete. In particular, the enzyme that hydroxylates JA to 12-OH-JA, an inactive form of JA that accumulates after wounding and pathogen attack, is unknown. Here, we report the identification of four paralogous 2-oxoglutarate/Fe(II)-dependent oxygenases in Arabidopsis thaliana as JA hydroxylases and show that they down-regulate JA-dependent responses. Because they are induced by JA we named them JASMONATE-INDUCED OXYGENASES (JOXs). Concurrent mutation of the four genes in a quadruple Arabidopsis mutant resulted in increased defense gene expression and increased resistance to the necrotrophic fungus Botrytis cinerea and the caterpillar Mamestra brassicae In addition, root and shoot growth of the plants was inhibited. Metabolite analysis of leaves showed that loss of function of the four JOX enzymes resulted in overaccumulation of JA and in reduced turnover of JA into 12-OH-JA. Transformation of the quadruple mutant with each JOX gene strongly reduced JA levels, demonstrating that all four JOXs inactivate JA in plants. The in vitro catalysis of 12-OH-JA from JA by recombinant enzyme could be confirmed for three JOXs. The identification of the enzymes responsible for hydroxylation of JA reveals a missing step in JA metabolism, which is important for the inactivation of the hormone and subsequent down-regulation of JA-dependent defenses.

  1. A Jasmonate ZIM-Domain Protein NaJAZd Regulates Floral Jasmonic Acid Levels and Counteracts Flower Abscission in Nicotiana attenuata Plants

    PubMed Central

    Oh, Youngjoo; Baldwin, Ian T.; Galis, Ivan

    2013-01-01

    Jasmonic acid is an important regulator of plant growth, development and defense. The jasmonate-ZIM domain (JAZ) proteins are key regulators in jasmonate signaling ubiquitously present in flowering plants but their functional annotation remains largely incomplete. Recently, we identified 12 putative JAZ proteins in native tobacco, Nicotiana attenuata, and initiated systematic functional characterization of these proteins by reverse genetic approaches. In this report, Nicotiana attenuata plants silenced in the expression of NaJAZd (irJAZd) by RNA interference were used to characterize NaJAZd function. Although NaJAZd transcripts were strongly and transiently up-regulated in the rosette leaves by simulated herbivory treatment, we did not observe strong defense-related phenotypes, such as altered herbivore performance or the constitutive accumulation of defense-related secondary metabolites in irJAZd plants compared to wild type plants, both in the glasshouse and the native habitat of Nicotiana attenuata in the Great Basin Desert, Utah, USA. Interestingly, irJAZd plants produced fewer seed capsules than did wild type plants as a result of increased flower abscission in later stages of flower development. The early- and mid-developmental stages of irJAZd flowers had reduced levels of jasmonic acid and jasmonoyl-L-isoleucine, while fully open flowers had normal levels, but these were impaired in NaMYB305 transcript accumulations. Previously, NaMYB305-silenced plants were shown to have strong flower abscission phenotypes and contained lower NECTARIN 1 transcript levels, phenotypes which are copied in irJAZd plants. We propose that the NaJAZd protein is required to counteract flower abscission, possibly by regulating jasmonic acid and jasmonoyl-L-isoleucine levels and/or expression of NaMYB305 gene in Nicotiana attenuata flowers. This novel insight into the function of JAZ proteins in flower and seed development highlights the diversity of functions played by jasmonates

  2. Parental Educational Attainment and Sense of Control in Mid-and Late-Adulthood

    ERIC Educational Resources Information Center

    Ward, Michael M.

    2013-01-01

    Sense of control is greater among children who grow up in households of higher socioeconomic status. It is unclear if this childhood advantage persists throughout life or if schooling and adulthood experiences override any early childhood advantage. Using data from 2 nationally representative samples of primarily middle-aged (National Survey of…

  3. Early detection and late cognitive control of emotional distraction by the prefrontal cortex

    PubMed Central

    García-Pacios, Javier; Garcés, Pilar; Del Río, David; Maestú, Fernando

    2015-01-01

    Unpleasant emotional distraction can impair the retention of non-emotional information in working memory (WM). Research links the prefrontal cortex with the successful control of such biologically relevant distractors, although the temporal changes in this brain mechanism remain unexplored. We use magnetoencephalography to investigate the temporal dynamics of the cognitive control of both unpleasant and pleasant distraction, in the millisecond (ms) scale. Behavioral results demonstrate that pleasant events do not affect WM maintenance more than neutral ones. Neuroimaging results show that prefrontal cortices are recruited for the rapid detection of emotional distraction, at early latencies of the processing (70-130 ms). Later in the processing (360-450 ms), the dorsolateral, the medial and the orbital sections of the prefrontal cortex mediate the effective control of emotional distraction. In accordance with the behavioral performance, pleasant distractors do not require higher prefrontal activity than neutral ones. These findings extend our knowledge about the brain mechanisms of coping with emotional distraction in WM. In particular, they show for the first time that overriding the attentional capture triggered by emotional distractors, while maintaining task-relevant elements in mind, is based on the early detection of such linked-to-survival information and on its later cognitive control by the prefrontal cortex. PMID:26067780

  4. The Paradoxical Role of Perceived Control in Late Life Health Behavior

    PubMed Central

    Chipperfield, Judith G.; Perry, Raymond P.; Pekrun, Reinhard; Barchfeld, Petra; Lang, Frieder R.; Hamm, Jeremy M.

    2016-01-01

    Research has established the health benefits of psychological factors, including the way individuals appraise outcomes. Although many studies confirm that appraising outcomes as controllable is adaptive for health, a paradoxical possibility is largely ignored: Perceived control may be detrimental under some conditions. Our premise was that appraising health as controllable but at the same time ascribing little value to it might signal a dysfunctional psychological mindset that fosters a mistaken sense of invincibility. During face-to-face interviews with a representative sample of older adults (age range = 72–99), we identified individuals with such a potentially maladaptive “invincible” mindset (high perceived control and low health value) and compared them to their counterparts on several outcomes. The findings were consistent with our hypotheses. The invincibles denied future risks, they lacked the activating emotion of fear, and they visited their physicians less often over a subsequent five-year period. Moreover, in contrast to their counterparts, the invincibles did not appear strategic in their approach to seeking care: Even poor health did not prompt them to seek the counsel of a physician. The recognition that psychological appraisals are modifiable highlights the promise of remedial methods to alter maladaptive mindsets, potentially improving quality of life. PMID:26974153

  5. The Late Pretest Problem in Randomized Control Trials of Education Interventions

    ERIC Educational Resources Information Center

    Schochet, Peter Z.

    2010-01-01

    Pretest-posttest experimental designs often are used in randomized control trials (RCTs) in the education field to improve the precision of the estimated treatment effects. For logistic reasons, however, pretest data often are collected after random assignment, so that including them in the analysis could bias the posttest impact estimates. Thus,…

  6. The Late Pretest Problem in Randomized Control Trials of Education Interventions. NCEE 2009-4033

    ERIC Educational Resources Information Center

    Schochet, Peter Z.

    2008-01-01

    Pretest-posttest experimental designs are often used in randomized control trials (RCTs) in the education field to improve the precision of the estimated treatment effects. For logistic reasons, however, pretest data are often collected after random assignment, so that including them in the analysis could bias the posttest impact estimates. Thus,…

  7. Parental Educational Attainment and Sense of Control in Mid-and Late-Adulthood

    ERIC Educational Resources Information Center

    Ward, Michael M.

    2013-01-01

    Sense of control is greater among children who grow up in households of higher socioeconomic status. It is unclear if this childhood advantage persists throughout life or if schooling and adulthood experiences override any early childhood advantage. Using data from 2 nationally representative samples of primarily middle-aged (National Survey of…

  8. Temporally Dissociable Mechanisms of Self-Control: Early Attentional Filtering Versus Late Value Modulation

    PubMed Central

    Hare, Todd; Rangel, Antonio

    2013-01-01

    Optimal decision-making often requires exercising self-control. A growing fMRI literature has implicated the dorsolateral prefrontal cortex (dlPFC) in successful self-control, but due to the limitations inherent in BOLD measures of brain activity, the neurocomputational role of this region has not been resolved. Here we exploit the high temporal resolution and whole-brain coverage of event-related potentials (ERPs) to test the hypothesis that dlPFC affects dietary self-control through two different mechanisms: attentional filtering and value modulation. Whereas attentional filtering of sensory input should occur early in the decision process, value modulation should occur later on, after the computation of stimulus values begins. Hungry human subjects were asked to make food choices while we measured neural activity using ERP in a natural condition, in which they responded freely and did not exhibit a tendency to regulate their diet, and in a self-control condition, in which they were given a financial incentive to lose weight. We then measured various neural markers associated with the attentional filtering and value modulation mechanisms across the decision period to test for changes in neural activity during the exercise of self-control. Consistent with the hypothesis, we found evidence for top-down attentional filtering early on in the decision period (150–200 ms poststimulus onset) as well as evidence for value modulation later in the process (450–650 ms poststimulus onset). We also found evidence that dlPFC plays a role in the deployment of both mechanisms. PMID:24285897

  9. The N400 and Late Positive Complex (LPC) Effects Reflect Controlled Rather than Automatic Mechanisms of Sentence Processing

    PubMed Central

    Daltrozzo, Jérôme; Wioland, Norma; Kotchoubey, Boris

    2012-01-01

    This study compared automatic and controlled cognitive processes that underlie event-related potentials (ERPs) effects during speech perception. Sentences were presented to French native speakers, and the final word could be congruent or incongruent, and presented at one of four levels of degradation (using a modulation with pink noise): no degradation, mild degradation (2 levels), or strong degradation. We assumed that degradation impairs controlled more than automatic processes. The N400 and Late Positive Complex (LPC) effects were defined as the differences between the corresponding wave amplitudes to incongruent words minus congruent words. Under mild degradation, where controlled sentence-level processing could still occur (as indicated by behavioral data), both N400 and LPC effects were delayed and the latter effect was reduced. Under strong degradation, where sentence processing was rather automatic (as indicated by behavioral data), no ERP effect remained. These results suggest that ERP effects elicited in complex contexts, such as sentences, reflect controlled rather than automatic mechanisms of speech processing. These results differ from the results of experiments that used word-pair or word-list paradigms. PMID:24961195

  10. Cholodny-Went revisited: a role for jasmonate in gravitropism of rice coleoptiles.

    PubMed

    Gutjahr, Caroline; Riemann, Michael; Müller, Axel; Düchting, Petra; Weiler, Elmar W; Nick, Peter

    2005-11-01

    Gravitropism is explained by the Cholodny-Went hypothesis: the basipetal flow of auxin is diverted laterally. The resulting lateral auxin gradient triggers asymmetric growth. However, the Cholodny-Went hypothesis has been questioned repeatedly because the internal auxin gradient is too small to account for the observed growth asymmetry. Therefore, an additional gradient in indolyl-3-acetic acid (IAA) sensitivity has been suggested (Brauner and Hager in Planta 51:115-147, 1958). We challenged the Cholodny-Went hypothesis for gravitropism of rice coleoptiles (Oryza sativa L.) and found it to be essentially true. However, we observed, additionally, that the two halves of gravitropically stimulated coleoptiles responded differentially to the same amount of exogenous auxin: the auxin response is reduced in the upper flank but normal in the lower flank. This indicates that the auxin-gradient is amplified by a gradient of auxin responsiveness. Hormone contents were measured across the coleoptile by a GC-MS/MS technique and a gradient of jasmonate was detected opposing the auxin gradient. Furthermore, the total content of jasmonate increased during the gravitropic response. Jasmonate gradient and increase persist even when the lateral IAA gradient is inhibited by 1-N-naphtylphtalamic acid. Flooding with jasmonate delays the onset of gravitropic bending. Moreover, a jasmonate-deficient rice mutant bends more slowly and later than the wild type. We discuss a role of jasmonate as modulator of auxin responsiveness in gravitropism.

  11. Jasmonate perception by inositol-phosphate-potentiated COI1-JAZ co-receptor

    SciTech Connect

    Sheard, Laura B; Tan, Xu; Mao, Haibin; Withers, John; Ben-Nissan, Gili; Hinds, Thomas R; Kobayashi, Yuichi; Hsu, Fong-Fu; Sharon, Michal; Browse, John; He, Sheng Yang; Rizo, Josep; Howe, Gregg A; Zheng, Ning

    2011-11-07

    Jasmonates are a family of plant hormones that regulate plant growth, development and responses to stress. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of transcriptional repressor JAZ proteins. Despite its importance, the mechanism of jasmonate perception remains unclear. Here we present structural and pharmacological data to show that the true Arabidopsis jasmonate receptor is a complex of both COI1 and JAZ. COI1 contains an open pocket that recognizes the bioactive hormone (3R,7S)-jasmonoyl-l-isoleucine (JA-Ile) with high specificity. High-affinity hormone binding requires a bipartite JAZ degron sequence consisting of a conserved {alpha}-helix for COI1 docking and a loop region to trap the hormone in its binding pocket. In addition, we identify a third critical component of the jasmonate co-receptor complex, inositol pentakisphosphate, which interacts with both COI1 and JAZ adjacent to the ligand. Our results unravel the mechanism of jasmonate perception and highlight the ability of F-box proteins to evolve as multi-component signalling hubs.

  12. Individual differences in control of language interference in late bilinguals are mainly related to general executive abilities

    PubMed Central

    2010-01-01

    Background Recent research based on comparisons between bilinguals and monolinguals postulates that bilingualism enhances cognitive control functions, because the parallel activation of languages necessitates control of interference. In a novel approach we investigated two groups of bilinguals, distinguished by their susceptibility to cross-language interference, asking whether bilinguals with strong language control abilities ("non-switchers") have an advantage in executive functions (inhibition of irrelevant information, problem solving, planning efficiency, generative fluency and self-monitoring) compared to those bilinguals showing weaker language control abilities ("switchers"). Methods 29 late bilinguals (21 women) were evaluated using various cognitive control neuropsychological tests [e.g., Tower of Hanoi, Ruff Figural Fluency Task, Divided Attention, Go/noGo] tapping executive functions as well as four subtests of the Wechsler Adult Intelligence Scale. The analysis involved t-tests (two independent samples). Non-switchers (n = 16) were distinguished from switchers (n = 13) by their performance observed in a bilingual picture-naming task. Results The non-switcher group demonstrated a better performance on the Tower of Hanoi and Ruff Figural Fluency task, faster reaction time in a Go/noGo and Divided Attention task, and produced significantly fewer errors in the Tower of Hanoi, Go/noGo, and Divided Attention tasks when compared to the switchers. Non-switchers performed significantly better on two verbal subtests of the Wechsler Adult Intelligence Scale (Information and Similarity), but not on the Performance subtests (Picture Completion, Block Design). Conclusions The present results suggest that bilinguals with stronger language control have indeed a cognitive advantage in the administered tests involving executive functions, in particular inhibition, self-monitoring, problem solving, and generative fluency, and in two of the intelligence tests. What

  13. Late functional outcomes after repair of tetralogy of Fallot with atrioventricular septal defect: a double case-match control study.

    PubMed

    Kotani, Yasuhiro; Chetan, Devin; Ono, Naoki; Mertens, Luc L; Caldarone, Christopher A; Van Arsdell, Glen S; Honjo, Osami

    2013-06-01

    We sought to elucidate late functional outcomes of the right ventricular outflow tract and atrioventricular valves after repair of tetralogy of Fallot with atrioventricular septal defect. From 1990 to 2010, the data from 41 patients who underwent repair were retrospectively reviewed. The median age at repair was 22.4 months (interquartile range, 10.8-41.6 months). Of the 41 patients, 13 (32%) had received previous palliations. The preoperative anatomic differences, physiologic differences, and long-term functional outcomes were determined using a double case-matched control with isolated tetralogy of Fallot and isolated atrioventricular septal defect. The right ventricular outflow tract was reconstructed, with the pulmonary valve preserved in 23 patients (56%). There were 3 early deaths and no late deaths. Survival was 92.1% at 15 years. During a median follow-up period of 5.9 years (interquartile range, 0.14-13.7 years), 29 reinterventions were performed in 13 (32%) patients. Freedom from all reintervention at 15 years was 52.8%. Of the 29 procedures, 12 (41%) were related to the right ventricular outflow tract. Freedom from right ventricular outflow tract-related reintervention was greater in patients who had their pulmonary valve preserved (95% vs 70% at 10 years; P = .046). Reinterventions were performed for the atrioventricular valve in 2 (5%) patients and subaortic stenosis in 1 (2%) patient. Freedom from right ventricular outflow tract-related reintervention (tetralogy of Fallot with atrioventricular septal defect, 88.6% vs tetralogy of Fallot alone, 83.9% at 5 years; P = .809) and atrioventricular valve/left ventricular outflow tract-related reintervention (tetralogy of Fallot with atrioventricular septal defect, 95.2% vs atrioventricular septal defect alone, 86.0% at 5 years; P = .332) were comparable between the tetralogy of Fallot with atrioventricular septal defect and matched control groups. Late survival and atrioventricular valve function after

  14. Phosphoinositide 3-kinase controls early and late events in mammalian cell division.

    PubMed

    García, Zaira; Kumar, Amit; Marqués, Miriam; Cortés, Isabel; Carrera, Ana C

    2006-02-22

    Phosphoinositide 3-kinase (PI3K) plays a crucial role in triggering cell division. To initiate this process, PI3K induces two distinct routes, of which one promotes cell growth and the other regulates cyclin-dependent kinases. Fine-tuned PI3K regulation is also required for later cell cycle phases. Here, we review the multiple points at which PI3K controls cell division and discuss its impact on human cancer.

  15. Jasmonic acid distribution and action in plants: regulation during development and response to biotic and abiotic stress.

    PubMed

    Creelman, R A; Mullet, J E

    1995-05-09

    Jasmonic acid (JA) is a naturally occurring growth regulator found in higher plants. Several physiological roles have been described for this compound (or a related compound, methyl jasmonate) during plant development and in response to biotic and abiotic stress. To accurately determine JA levels in plant tissue, we have synthesized JA containing 13C for use as an internal standard with an isotopic composition of [225]:[224] 0.98:0.02 compared with [225]:[224] 0.15:0.85 for natural material. GC analysis (flame ionization detection and MS) indicate that the internal standard is composed of 92% 2-(+/-)-[13C]JA and 8% 2-(+/-)-7-iso-[13C]JA. In soybean plants, JA levels were highest in young leaves, flowers, and fruit (highest in the pericarp). In soybean seeds and seedlings, JA levels were highest in the youngest organs including the hypocotyl hook, plumule, and 12-h axis. In soybean leaves that had been dehydrated to cause a 15% decrease in fresh weight, JA levels increased approximately 5-fold within 2 h and declined to approximately control levels by 4 h. In contrast, a lag time of 1-2 h occurred before abscisic acid accumulation reached a maximum. These results will be discussed in the context of multiple pathways for JA biosynthesis and the role of JA in plant development and responses to environmental signals.

  16. Metabolomic analysis of methyl jasmonate-induced triterpenoid production in the medicinal herb Centella asiatica (L.) urban.

    PubMed

    James, Jacinda T; Tugizimana, Fidele; Steenkamp, Paul A; Dubery, Ian A

    2013-04-11

    Centella asiatica is an important source of biologically active pentacyclic triterpenoids. The enhancement of the biosynthesis of the centellosides by manipulation of associated metabolic pathways is receiving much attention. Jasmonates play critical roles in plant metabolism by up-regulating the expression of genes related to secondary metabolites. Here, we investigated the effect of methyl jasmonate (MeJa) in C. asiatica through targeted metabolomic profiling of asiaticoside and madecassoside as well as their aglycones, asiatic acid and madecassic acid. Cell suspensions were treated with 0.2 mM MeJa for 2, 4 and 6 days. Liquid chromatography coupled to mass spectrometry (LC-MS) was used to explore induced changes in metabolite profiles, both qualitatively and quantitatively. Principal component analysis (PCA)-derived scores plots revealed clusters of sample replicates for control and treated samples at 2, 4 and 6 days while loading plots aided in identifying signatory biomarkers (asiatic acid and madecassic acid, as well as asiaticoside and madecassoside) that clearly demonstrate the variability between samples. In addition to increased biosynthesis of the targeted centelloids, other differential changes in the intracellular metabolite profiles reflected the response of the C. asiatica cells to the MeJa-treatment as a reprogramming of the metabolome.

  17. Elevated levels of CYP94 family gene expression alleviate the jasmonate response and enhance salt tolerance in rice.

    PubMed

    Kurotani, Ken-ichi; Hayashi, Kenji; Hatanaka, Saki; Toda, Yosuke; Ogawa, Daisuke; Ichikawa, Hiroaki; Ishimaru, Yasuhiro; Tashita, Ryo; Suzuki, Takeshi; Ueda, Minoru; Hattori, Tsukaho; Takeda, Shin

    2015-04-01

    The plant hormone jasmonate and its conjugates (JAs) have important roles in growth control, leaf senescence and defense responses against insects and microbial attacks. JA biosynthesis is induced by several stresses, including mechanical wounding, pathogen attacks, drought and salinity stresses. However, the roles of JAs under abiotic stress conditions are unclear. Here we report that increased expression of the Cyt P450 family gene CYP94C2b enhanced viability of rice plants under saline conditions. This gene encodes an enzyme closely related to CYP94C1 that catalyzes conversion of bioactive jasmonate-isoleucine (JA-Ile) into 12OH-JA-Ile and 12COOH-JA-Ile. Inactivation of JA was facilitated in a rice line with enhanced CYP94C2b expression, and responses to exogenous JA and wounding were alleviated. Moreover, salt stress-induced leaf senescence but not natural senescence was delayed in the transgenic rice. These results suggest that bioactive JAs have a negative effect on viability under salt stress conditions and demonstrate that manipulating JA metabolism confers enhanced salt tolerance in rice.

  18. Manipulation of VOC emissions with methyl jasmonate and carrageenan in the evergreen conifer Pinus sylvestris and evergreen broadleaf Quercus ilex.

    PubMed

    Semiz, G; Blande, J D; Heijari, J; Işik, K; Niinemets, U; Holopainen, J K

    2012-03-01

    Plant defence can be induced by exposing plants to the plant hormone jasmonic acid (JA) or its volatile ester, methyl jasmonate (MeJA). Carrageenans (Carr) - sulphated D-galactans extracted from red algae - can also induce plant defences. In this study, the effects of exogenous MeJA and Carr application (concentration 300 and 12.7 μmol, respectively) on volatile emissions from two widespread evergreen woody species, Pinus sylvestris (nine Turkish and one Finnish provenance) and Quercus ilex (Italian provenance) were investigated. We collected headspace samples from seedlings and analysed the quality and quantity of volatile compounds emitted by treated and control plants. In total, 19 monoterpenes, 10 sesquiterpenes, 10 green leaf volatiles (GLVs) and two aromatic compounds were emitted by P. sylvestris from all the provenances studied. Foliar MeJA application clearly affected the volatile profiles of trees from all the provenances. Effects of Carr were genotype specific. In Q. ilex, emissions of sesquiterpenes, GLVs and the homoterpene (E)-DMNT were all induced by MeJA application. However, emissions of most constitutively emitted monoterpenes were significantly reduced. Carr application also led to a significant reduction in monoterpene emissions, but without corresponding increases in other emissions. Our results indicate that exogenously applied MeJA and Carr can both significantly modify the volatile profiles of P. sylvestris and Q. ilex, but also that there are important provenance- and species-specific differences in the overall degree of elicitation and compositions of elicited compounds.

  19. Transcriptome profiling shows gene regulation patterns in ginsenoside pathway in response to methyl jasmonate in Panax Quinquefolium adventitious root

    PubMed Central

    Wang, Juan; Li, Jinxin; Li, Jianli; Liu, Shujie; Wu, Xiaolei; Li, Jing; Gao, Wenyuan

    2016-01-01

    Here, we combine elicitors and transcriptomics to investigate the inducible biosynthesis of the ginsenoside from the Panax quinquefolium. Treatment of P. quinquefolium adventitious root with methyl jasmonate (MJ) results in an increase in ginsenoside content (43.66 mg/g compared to 8.32 mg/g in control group). Therefore, we sequenced the transcriptome of native and MJ treated adventitious root in order to elucidate the key differentially expressed genes (DEGs) in the ginsenoside biosynthetic pathway. Through DEG analysis, we found that 5,759 unigenes were up-regulated and 6,389 unigenes down-regulated in response to MJ treatment. Several defense-related genes (48) were identified, participating in salicylic acid (SA), jasmonic acid (JA), nitric oxide (NO) and abscisic acid (ABA) signal pathway. Additionally, we mapped 72 unigenes to the ginsenoside biosynthetic pathway. Four cytochrome P450s (CYP450) were likely to catalyze hydroxylation at C-16 (c15743_g1, c39772_g1, c55422_g1) and C-30 (c52011_g1) of the triterpene backbone. UDP-xylose synthases (c52571_g3) was selected as the candidate, which was likely to involve in ginsenoside Rb3 biosynthesis. PMID:27876840

  20. Analysis of plant-bacteria interactions in their native habitat: bacterial communities associated with wild tobacco are independent of endogenous jasmonic acid levels and developmental stages.

    PubMed

    Santhanam, Rakesh; Groten, Karin; Meldau, Dorothea G; Baldwin, Ian T

    2014-01-01

    Jasmonic acid (JA) mediates defense responses against herbivores and necrotrophic pathogens but does it influence the recruitment of bacterial communities in the field? We conducted field and laboratory experiments with transformed Nicotiana attenuata plants deficient in jasmonate biosynthesis (irAOC) and empty vector controls (EV) to answer this question. Using both culture-dependent and independent techniques, we characterized root and leaf-associated bacterial communities over five developmental stages, from rosette through flowering of plants grown in their natural habitat. Based on the pyrosequencing results, alpha and beta diversity did not differ among EV and irAOC plants or over ontogeny, but some genera were more abundant in one of the genotypes. Furthermore, bacterial communities were significantly different among leaves and roots. Taxa isolated only from one or both plant genotypes and hence classified as 'specialists' and 'generalists' were used in laboratory tests to further evaluate the patterns observed from the field. The putative specialist taxa did not preferentially colonize the jasmonate-deficient genotype, or alter the plant's elicited phytohormone signaling. We conclude that in N. attenuata, JA signaling does not have a major effect on structuring the bacterial communities and infer that colonization of plant tissues is mainly shaped by the local soil community in which the plant grows.

  1. Improvement of grape and wine phenolic content by foliar application to grapevine of three different elicitors: Methyl jasmonate, chitosan, and yeast extract.

    PubMed

    Portu, Javier; López, Rosa; Baroja, Elisa; Santamaría, Pilar; Garde-Cerdán, Teresa

    2016-06-15

    Phenolic compounds play a key role in grape and wine organoleptic properties, being therefore a key parameter in wine quality. Elicitor application constitutes an interesting field of research since it is indirectly involved in the accumulation of phenolic compounds. The aim of this study was to compare the effect of the application of three different elicitors on both grape and wine phenolic content. Methyl jasmonate, chitosan, and a commercial yeast extract were applied to the canopy at veraison and one week later. Results showed that foliar treatments carried out with methyl jasmonate and yeast extract achieved the best results, increasing grape and wine anthocyanin content when compared to the control. Moreover, the application of the yeast elicitor also enhanced grape stilbene content. In contrast, the chitosan treatment did not have a substantial impact on the phenolic compounds. The results of this study indicate that methyl jasmonate and yeast extract applications could be a simple practice to increase grape and wine phenolic content. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Analysis of Plant-Bacteria Interactions in Their Native Habitat: Bacterial Communities Associated with Wild Tobacco Are Independent of Endogenous Jasmonic Acid Levels and Developmental Stages

    PubMed Central

    Santhanam, Rakesh; Groten, Karin; Meldau, Dorothea G.; Baldwin, Ian T.

    2014-01-01

    Jasmonic acid (JA) mediates defense responses against herbivores and necrotrophic pathogens but does it influence the recruitment of bacterial communities in the field? We conducted field and laboratory experiments with transformed Nicotiana attenuata plants deficient in jasmonate biosynthesis (irAOC) and empty vector controls (EV) to answer this question. Using both culture-dependent and independent techniques, we characterized root and leaf-associated bacterial communities over five developmental stages, from rosette through flowering of plants grown in their natural habitat. Based on the pyrosequencing results, alpha and beta diversity did not differ among EV and irAOC plants or over ontogeny, but some genera were more abundant in one of the genotypes. Furthermore, bacterial communities were significantly different among leaves and roots. Taxa isolated only from one or both plant genotypes and hence classified as ‘specialists’ and ‘generalists’ were used in laboratory tests to further evaluate the patterns observed from the field. The putative specialist taxa did not preferentially colonize the jasmonate-deficient genotype, or alter the plant's elicited phytohormone signaling. We conclude that in N. attenuata, JA signaling does not have a major effect on structuring the bacterial communities and infer that colonization of plant tissues is mainly shaped by the local soil community in which the plant grows. PMID:24728407

  3. A chloroplast lipoxygenase is required for wound-induced jasmonic acid accumulation in Arabidopsis.

    PubMed

    Bell, E; Creelman, R A; Mullet, J E

    1995-09-12

    Plant lipoxygenases are thought to be involved in the biosynthesis of lipid-derived signaling molecules. The potential involvement of a specific Arabidopsis thaliana lipoxygenase isozyme, LOX2, in the biosynthesis of the plant growth regulators jasmonic acid (JA) and abscisic acid was investigated. Our characterization of LOX2 indicates that the protein is targeted to chloroplasts. The physiological role of this chloroplast lipoxygenase was analyzed in transgenic plants where cosuppression reduced LOX2 accumulation. The reduction in LOX2 levels caused no obvious changes in plant growth or in the accumulation of abscisic acid. However, the wound-induced accumulation of JA observed in control plants was absent in leaves of transgenic plants that lacked LOX2. Thus, LOX2 is required for the wound-induced synthesis of the plant growth regulator JA in leaves. We also examined the expression of a wound- and JA-inducible Arabidopsis gene, vsp, in transgenic and control plants. Leaves of transgenic plants lacking LOX2 accumulated less vsp mRNA than did control leaves in response to wounding. This result suggests that wound-induced JA (or some other LOX2-requiring component of the wound response pathway) is involved in the wound-induced regulation of this gene.

  4. Effect of methyl jasmonate on secondary metabolites of sweet basil (Ocimum basilicum L.).

    PubMed

    Kim, Hyun-Jin; Chen, Feng; Wang, Xi; Rajapakse, Nihal C

    2006-03-22

    The effect of methyl jasmonate (MeJA) in terms of its induction of inherent bioactive chemicals in sweet basil (Ocimum basilicum L.) was evaluated after MeJA was sprayed on healthy basil plants. The total phenolic content of the sweet basil significantly increased after 0.1 and 0.5 mM MeJA treatments compared with the control not subjected to MeJA. Two phenolic compounds, rosmarinic acid (RA) and caffeic acid (CA), were identified as strong antioxidant constituents of the sweet basil. Their amounts also significantly increased after the MeJA treatment. In addition, eugenol and linalool increased 56 and 43%, respectively, by the 0.5 mM MeJA treatment. Due to the accumulation of RA, CA, and eugenol, which possess strong 2,2-diphenyl-1-picrylhydrazyl (DPPH*) free radical scavenging activities, the antioxidant activity of the sweet basil extract was 2.3-fold greater than that of the control after the 0.5 mM MeJA treatment. In the DPPH* assay, the EC50 values of RA, CA, and eugenol were determined as 23, 46, and 59 microM, respectively, which indicated they were 6-, 3-, and 2.4-fold more efficient than BHT (140 microM). Besides, an unidentified HPLC peak in the methanolic extract of the sweet basil was 4.3-fold higher than that of the control after the 0.5 mM MeJA treatment.

  5. Responses of herbivore and predatory mites to tomato plants exposed to jasmonic acid seed treatment.

    PubMed

    Smart, Lesley E; Martin, Janet L; Limpalaër, Marlène; Bruce, Toby J A; Pickett, John A

    2013-10-01

    Jasmonic acid (JA) signalling can influence plant defense and the production of plant volatiles that mediate interactions with insects. Here, we tested whether a JA seed treatment could alter direct and indirect defenses. First, oviposition levels of herbivorous mites, Tetranychus urticae, on JA seed-treated and control tomato plants were compared. They were not significantly different on tomato cv. 'Moneymaker', however, there was a significant reduction in oviposition on treated plants in additional experiments with cv. 'Carousel'. Second, responses of predatory mites, Phytoseiulus persimilis, were assessed in a Y-tube olfactometer. Volatiles from JA seed-treated tomato cv. 'Moneymaker' plants were significantly more attractive than volatiles from control plants. Volatiles collected from plants were analysed by GC/MS, and samples from JA seed-treated plants contained more methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT) than samples from control plants. Our results indicate that JA seed treatment can make tomato plants more attractive to predatory mites, but that direct effects on herbivorous mites are variable and cultivar dependent.

  6. Methyl Jasmonate Ameliorates Testosterone Propionate-induced Prostatic Hyperplasia in Castrated Wistar Rats.

    PubMed

    Akanni, Olubukola Oyebimpe; Abiola, Olusoji John; Adaramoye, Oluwatosin Adekunle

    2017-04-01

    Benign prostate hyperplasia (BPH) is a progressive disease that is related to age. Known therapeutic agents used in the treatment of BPH are associated with toxicity. Therefore, chemoprevention could be an effective approach. We investigated the ameliorative effects of methyl jasmonate (MeJA) in testosterone propionate (TP)-induced BPH in castrated rats. Castration was performed by removing both testes through the scrotum sack under ketamine anesthesia. Rats were assigned into seven groups of seven animals each: non-castrated control, castrated control, castrated rats that received TP, castrated rats that received TP and MeJA, castrated rats that received TP and finasteride, castrated rats that received MeJA, and castrated rats that received finasteride. Results indicate that BPH rats had significantly (p < 0.05) elevated prostate weight and relative weight of prostate relative to control. Also, BPH rats had significantly (p < 0.05) increased activities of prostatic acid and alkaline phosphatases, levels of zinc, and malondialdehyde. Further, levels of enzymic and non-enzymic antioxidative indices were significantly (p < 0.05) reduced in BPH. Histology of prostate revealed hyperplasia of transition lobe, increased expression of PSA, and Ki67 in BPH. Treatment with MeJA and finasteride attenuated the activities of the phosphatases and levels of antioxidants in BPH. Overall, MeJA ameliorates BPH via antioxidative mechanism. Copyright © 2017 John Wiley & Sons, Ltd.

  7. Dynamic versus flexural controls of Late Cretaceous Western Interior Basin, USA

    NASA Astrophysics Data System (ADS)

    Liu, Shaofeng; Nummedal, Dag; Gurnis, Michael

    2014-03-01

    The United States Cretaceous Western Interior Basin has long been considered a foreland basin, driven by the Sevier thrust and associated basin sediment loads. However, flexural studies demonstrate that this effect exists only within a narrow band in front of the thrust belt. Most of the basin appears to be due to mantle flow-induced dynamic subsidence associated with Farallon plate subduction. Here we show how the components of evolving long-wavelength dynamic subsidence and flexural subsidence created the accommodation space and controlled the stratigraphy across the western United States, based on a correlated stratigraphic section across central Utah and Colorado. These backstripped subsidence data reveal the dynamic-topography driven nature of the Western Interior Basin. The results seem to support that the depocenters track the trough of dynamic subsidence with ca. 18 Myr cycles through time and space and the stratigraphic patterns of large-scale progradation, eastward migration of depocenter, and regional clinoform-like downlap are related with the dynamic subsidence. Interpretation of these data also provides more insights into the repeated, ca. 2 to 6 Myr cycles of thrust-induced subsidence in front of the thrust belt, which control the local eastward progradation of the sand bodies from the thrust belt. The dynamic, flexural subsidence and eustatic sea level changes interacted and controlled the timing and distribution of unconformities. Our work shows how the stratigraphy precisely records the timing, patterns and position of dynamic versus flexural subsidences, and that combination of such data leads to important geophysical discoveries and supplies strict constraints for geodynamic modeling.

  8. Dynamic versus flexural controls of Late Cretaceous Western Interior Basin, USA

    NASA Astrophysics Data System (ADS)

    Liu, Shaofeng; Nummedal, Dag; Gurnis, Michael

    2014-05-01

    The United States Cretaceous Western Interior Basin has long been considered a foreland basin, driven by the Sevier thrust and associated basin sediment loads. However, flexural studies demonstrate that this effect exists only within a narrow band in front of the thrust belt. Most of the basin appears to be due to mantle flow-induced dynamic subsidence associated with Farallon plate subduction. Here we show how the components of evolving long-wavelength dynamic subsidence and flexural subsidence created the accommodation space and controlled the stratigraphy across the western United States, based on a correlated stratigraphic section across central Utah and Colorado. These backstripped subsidence data reveal the dynamic-topography driven nature of the Western Interior Basin. The results seem to support the hypothesis that the depocenters track the trough of dynamic subsidence with ca. 18 Myr cycles through time and space and the stratigraphic patterns of large-scale progradation, eastward migration of depocenter, and regional clinoform-like downlap are related with the dynamic subsidence. Interpretation of these data also provides more insights into the repeated, ca. 2 to 6 Myr cycles of thrust-induced subsidence in front of the thrust belt, which control the local eastward progradation of the sand bodies from the thrust belt. The dynamic, flexural subsidence and eustatic sea level changes interacted and controlled the timing and distribution of unconformities. Our work shows how the stratigraphy precisely records the timing, patterns and position of dynamic versus flexural subsidences, and that combination of such data leads to important geophysical discoveries and supplies strict constraints for geodynamic modeling.

  9. Application of an alcohol clamp paradigm to examine inhibitory control, subjective responses, and acute tolerance in late adolescence.

    PubMed

    Hendershot, Christian S; Wardell, Jeffrey D; Strang, Nicole M; Markovich, Mike S D; Claus, Eric D; Ramchandani, Vijay A

    2015-06-01

    Individual differences in acute alcohol effects on cognitive control and subjective responses--and acute tolerance to these effects--are implicated in the risk for heavy drinking and alcohol-related harms. Few studies have examined these effects in drinkers under age 21. Additionally, studies of acute tolerance typically involve bolus oral alcohol administration, such that estimates of tolerance are confounded with blood alcohol concentration (BAC) limb. The current study examined cognitive control and subjective responses in young heavy drinkers (n = 88; M = 19.8 years old, SD = 0.8) during a single-session alcohol clamp protocol. Participants completed an intravenous alcohol session comprising an ascending limb (0 to 80 mg% in 20 min) and a BAC plateau (80 mg% for 80 min). Serial assessments included a cued go/no-go task and measures of stimulation, sedation, and craving. Relevant individual difference factors (attention-deficit hyperactivity disorder [ADHD] symptoms and sensation seeking) were examined as moderators. Multilevel modeling demonstrated that response inhibition worsened following initial rise in BAC and showed increasing impairment during the BAC plateau. ADHD symptoms and sensation seeking moderated this effect. Significant within-person associations between stimulation and craving were evident on the ascending limb only. Participants with higher ADHD symptoms reported steeper increases in stimulation during the ascending limb. These findings provide initial information about subjective and behavioral responses during pseudoconstant BAC, and potential moderators of these outcomes, in late adolescence. Additional studies with placebo-controlled designs are necessary to confirm these findings.

  10. Development of attentional control of verbal auditory perception from middle to late childhood: comparisons to healthy aging.

    PubMed

    Passow, Susanne; Müller, Maike; Westerhausen, René; Hugdahl, Kenneth; Wartenburger, Isabell; Heekeren, Hauke R; Lindenberger, Ulman; Li, Shu-Chen

    2013-10-01

    Multitalker situations confront listeners with a plethora of competing auditory inputs, and hence require selective attention to relevant information, especially when the perceptual saliency of distracting inputs is high. This study augmented the classical forced-attention dichotic listening paradigm by adding an interaural intensity manipulation to investigate developmental differences in the interplay between perceptual saliency and attentional control during auditory processing between early and middle childhood. We found that older children were able to flexibly focus on instructed auditory inputs from either the right or the left ear, overcoming the effects of perceptual saliency. In contrast, younger children implemented their attentional focus less efficiently. Direct comparisons of the present data with data from a recently published study of younger and older adults from our group suggest that younger children and older adults show similar levels of performance. Critically, follow-up comparisons revealed that younger children's performance restrictions reflect difficulties in attentional control only, whereas older adults' performance deficits also reflect an exaggerated reliance on perceptual saliency. We conclude that auditory attentional control improves considerably from middle to late childhood and that auditory attention deficits in healthy aging cannot be reduced to a simple reversal of child developmental improvements.

  11. Phenotypic Similarities Between Late-Onset Autosomal Dominant and Sporadic Alzheimer Disease: A Single-Family Case-Control Study.

    PubMed

    Day, Gregory S; Musiek, Erik S; Roe, Catherine M; Norton, Joanne; Goate, Alison M; Cruchaga, Carlos; Cairns, Nigel J; Morris, John C

    2016-09-01

    The amyloid hypothesis posits that disrupted β-amyloid homeostasis initiates the pathological process resulting in Alzheimer disease (AD). Autosomal dominant AD (ADAD) has an early symptomatic onset and is caused by single-gene mutations that result in overproduction of β-amyloid 42. To the extent that sporadic late-onset AD (LOAD) also results from dysregulated β-amyloid 42, the clinical phenotypes of ADAD and LOAD should be similar when controlling for the effects of age. To use a family with late-onset ADAD caused by a presenilin 1 (PSEN1) gene mutation to mitigate the potential confound of age when comparing ADAD and LOAD. This case-control study was conducted at the Knight Alzheimer Disease Research Center at Washington University, St Louis, Missouri, and other National Institutes of Aging-funded AD centers in the United States. Ten PSEN1 A79V mutation carriers from multiple generations of a family with late-onset ADAD and 12 noncarrier family members were followed up at the Knight Alzheimer Disease Research Center (1985-2015) and 1115 individuals with neuropathologically confirmed LOAD were included from the National Alzheimer Coordinating Center database (September 2005-December 2014). Data analysis was completed in January 2016, including Knight Alzheimer Disease Research Center patient data collected up until the end of 2015. Planned comparison of clinical characteristics between cohorts, including age at symptom onset, associated symptoms and signs, rates of progression, and disease duration. Of the PSEN1 A79V carriers in the family with late-onset ADAD, 4 were female (57%); among those with LOAD, 529 were female (47%). Seven mutation carriers (70%) developed AD dementia, while 3 were yet asymptomatic in their seventh and eighth decades of life. No differences were observed between mutation carriers and individuals with LOAD concerning age at symptom onset (mutation carriers: mean, 75 years [range, 63-77 years] vs those with LOAD: mean, 74 years [range

  12. Class I Chitinase and β-1,3-Glucanase Are Differentially Regulated by Wounding, Methyl Jasmonate, Ethylene, and Gibberellin in Tomato Seeds and Leaves1

    PubMed Central

    Wu, Chun-Ta; Bradford, Kent J.

    2003-01-01

    Class I chitinase (Chi9) and β-1,3-glucanase (GluB) genes are expressed in the micropylar endosperm cap of tomato (Lycopersicon esculentum) seeds just before radicle emergence through this tissue to complete germination. In gibberellin (GA)-deficient mutant (gib-1) seeds, expression of Chi9 and GluB mRNA and protein is dependent upon GA. However, as expression occurs relatively late in the germination process, we investigated whether the genes are induced indirectly in response to tissue wounding associated with endosperm cap weakening and radicle protrusion. Wounding and methyl jasmonate (MeJA) induced Chi9 expression, whereas ethylene, abscisic acid, sodium salicylate, fusicoccin, or β-aminobutyric acid were without effect. Chi9 expression occurred only in the micropylar tissues when seeds were exposed to MeJA or were wounded at the chalazal end of the seed. Expression of Chi9, but not GluB, mRNA was reduced in germinating seeds of the jasmonate-deficient defenseless1 tomato mutant and could be restored by MeJA treatment. Chi9 expression during germination may be associated with “wounding” from cell wall hydrolysis and weakening in the endosperm cap leading to radicle protrusion, and jasmonate is involved in the signaling pathway for this response. Among these treatments and chemicals (other than GA), only MeJA and wounding induced a low level of GluB expression in gib-1 seeds. However, MeJA, wounding, and particularly ethylene induced both genes in leaves, whereas GA induced only Chi9 in leaves. Although normally expressed simultaneously during tomato seed germination, Chi9 and GluB genes are regulated distinctly and tissue specifically by hormones and wounding. PMID:12970492

  13. Systemic jasmonic acid modulation in mycorrhizal tomato plants and its role in induced resistance against Alternaria alternata.

    PubMed

    Nair, A; Kolet, S P; Thulasiram, H V; Bhargava, S

    2015-05-01

    Tomato plants colonised with the arbuscular mycorrhizal (AM) fungus Glomus fasciculatum show systemic induced resistance to the foliar pathogen Alternaria alternata, as observed in interactions of other AM-colonised plants with a range of pathogens. The role of jasmonic (JA) and salicylic (SA) acid in expression of this mycorrhiza-induced resistance (MIR) against A. alternata was studied by measuring: (i) activity of enzymes reported to be involved in their biosynthesis, namely lipoxygenase (LOX) and phenylammonia lyase (PAL); and (ii) levels of methyl jasmonate (MeJA) and SA. Transcript abundance of some defence genes associated with JA and SA response pathways were also studied. Both LOX and PAL activity increased twofold in response to pathogen application to control plants. AM-colonised plants had three-fold higher LOX activity compared to control plants, but unlike controls, this did not increase further in response to pathogen application. Higher LOX activity in AM-colonised plants correlated with four-fold higher MeJA in leaves of AM-colonised plants compared to controls. Treatment of plants with the JA biosynthesis inhibitor salicylhydroxamic acid (SHAM) led to 50% lower MeJA in both control and AM-colonised plants and correlated with increased susceptibility to A. alternata, suggesting a causal role for JA in expression of MIR against the pathogen. Genes involved in JA biosynthesis (OPR3) and response (COI1) showed six- and 42-fold higher expression, respectively, in leaves of AM-colonised plants compared to controls. AM-colonised plants also showed increased expression of the SA response gene PR1 and that of the wound-inducible polypeptide prosystemin. Our results suggest that the systemic increase in JA in response to AM colonisation plays a key role in expression of MIR against A. alternata.

  14. Pre-harvest methyl jasmonate treatment enhances cauliflower chemoprotective attributes without a loss in postharvest quality.

    PubMed

    Ku, Kang Mo; Choi, Jeong-Hee; Kushad, Mosbah M; Jeffery, Elizabeth H; Juvik, John A

    2013-06-01

    Methyl jasmonate (MeJA) treatment can significantly increase glucosinolate (GS) concentrations in Brassica vegetables and potentially enhance anticancer bioactivity. Although MeJA treatment may promote ethylene biosynthesis, which can be detrimental to postharvest quality, there are no previous reports of its effect on cauliflower postharvest quality. To address this, cauliflower curds in field plots were sprayed with either 0.1 % Triton X-100 (control) or 500 μM MeJA solutions four days prior to harvest, then stored at 4 °C. Tissue subsamples were collected after 0, 10, 20, and 30 days of postharvest storage and assayed for visual color change, ethylene production, GS concentrations, and extract quinone reductase inductive activity. MeJA treatment increased curd GS concentrations of glucoraphanin, glucobrassicin, and neoglucobrassicin by 1.5, 2.4, and 4.6-fold over controls, respectively. MeJA treated cauliflower showed significantly higher quinone reductase activity, a biomarker for anticancer bioactivity, without reducing visual color and postharvest quality for 10 days at 4 °C storage.

  15. Effect of methyl jasmonate on the anthocyanin content and antioxidant activity of blueberries during cold storage.

    PubMed

    Huang, Xiaojie; Li, Jing; Shang, Hongli; Meng, Xin

    2015-01-01

    The effects of postharvest methyl jasmonate (MeJA) fumigation on total soluble solids (TSS), titratable acidity (TA), ascorbic acid, total phenolic content (TPC), total monomeric anthocyanins (TMAs), individual anthocyanins and antioxidant activity of blueberries stored at 1 °C for 28 days were evaluated. Prior to storage, the blueberries were fumigated with 0.05 mmol L(-1) MeJA for 12 h. Control blueberries were subjected to the same conditions but were not exposed to MeJA. MeJA treatment had no adverse effect on TSS and TA and inhibited the decrease in ascorbic acid during storage. MeJA treatment induced an enhancement in TPC on day 21; TPC decreased thereafter. Similarly, a significant increase in TMAs and individual anthocyanins was observed 21 days after MeJA treatment. TPC, TMAs and individual anthocyanins increased in control fruits on day 7 and decreased thereafter. Moreover, MeJA treatment maintained higher levels of antioxidant activity during the entire storage period. These results suggest that cold storage enhances TPC, TMAs and individual anthocyanin content during short-term storage. However, postharvest application of MeJA to blueberries enhances TPC, TMAs and individual anthocyanin content during long-term storage. © 2014 Society of Chemical Industry.

  16. Transcriptome changes in Polygonum multiflorum Thunb. roots induced by methyl jasmonate* #

    PubMed Central

    Liu, Hong-chang; Wu, Wei; Hou, Kai; Chen, Jun-wen; Zhao, Zhi

    2015-01-01

    Transcriptome profiling has been widely used to analyze transcriptomic variation in plants subjected to abiotic or biotic stresses. Although gene expression changes induced by methyl jasmonate (MeJA) have been profiled in several plant species, no information is available on the MeJA-triggered transcriptome response of Polygonum multiflorum Thunb., a species with highly valuable medicinal properties. In this study, we used transcriptome profiling to investigate transcriptome changes in roots of P. multiflorum seedlings subjected to a 0.25 mmol/L-MeJA root irrigation treatment. A total of 18 677 differentially expressed genes (DEGs) were induced by MeJA treatment, of which 4535 were up-regulated and 14 142 were down-regulated compared with controls. These DEGs were associated with 125 metabolic pathways. In addition to various common primary and secondary metabolic pathways, several secondary metabolic pathways related to components with significant pharmacological effects were enriched by MeJA, including arachidonic acid metabolism, linoleic acid metabolism, and stilbenoid biosynthesis. The MeJA-induced transcriptome changes uncovered in this study provide a solid foundation for future study of functional genes controlling effective components in secondary metabolic pathways of P. multiflorum. PMID:26642186

  17. Effect of methyl jasmonate on phenolic compounds and carotenoids of romaine lettuce (Lactuca sativa L.).

    PubMed

    Kim, Hyun-Jin; Fonseca, Jorge M; Choi, Ju-Hee; Kubota, Chieri

    2007-12-12

    The effect of exogenous methyl jasmonate (MeJA) on antioxidative compounds of romaine lettuce ( Lactuca sativa L.) was investigated. Lettuces were treated with various MeJA solutions (0, 0.05, 0.1, 0.25, and 0.5 mM) before harvest. Total phenolic compounds content and antioxidant capacity of romaine lettuce significantly increased after MeJA treatments (0.1, 0.25, and 0.5 mM). The total content of phenolic compounds of the romaine lettuce treated with 0.5 mM MeJA (31.6 microg of gallic acid equivalents/mg of dry weight) was 35% higher than that of the control. The increase in phenolic compound content was attributed to a caffeic acid derivative and an unknown phenolic compound, which also contributed to increased antioxidant capacity. The induction of phenylalanine ammonia-lyase (PAL) activity by the MeJA treatment indicated that phenolic compounds were altered due to the activation of the phenylpropandoid pathway. Total content of carotenoids, including lutein and beta-carotene, of the MeJA-treated lettuce did not change after 8 days of treatment, whereas the content of the control without MeJA decreased after 8 days. This research indicated that preharvest application of MeJA could increase the nutritional value of romaine lettuce under determined conditions discussed in this work.

  18. Chronotype in patients with epilepsy: A controlled study in 60 subjects with late-onset focal epilepsy.

    PubMed

    Manni, Raffaele; Cremascoli, Riccardo; De Icco, Roberto; Terzaghi, Michele

    2015-09-01

    Studies based on self-administered questionnaires indicate that most patients with epilepsy are morning-oriented. We aimed to investigate chronotype in patients with epilepsy with late-onset focal epilepsy by combining subjective data with dim light melatonin onset (DLMO) as an objective marker of the circadian phase. Sixty adult patients (mean age 46.5±13.8; 27 males) with late-onset focal epilepsy under pharmacological treatment were prospectively studied. Subjective chronotype was determined using the Morningness-Eveningness Questionnaire (MEQ) and circadian phase through analysis of salivary melatonin secretion, considering 3pg/ml as the dim light melatonin onset (DLMO) threshold. The mean MEQ score was significantly higher in the patients with epilepsy than in the controls, and significantly, more patients had a MEQ score indicative of the morning type (50.0% vs 30.0%, p=0.02). However, no significant differences were found in mean time of DLMO (21:38±01:21 vs 21:26±01:03; p=ns), and DLMO time was in the range indicative of an intermediate chronotype in both patients and controls. Sleep onset and sleep offset phase angles were significantly shorter in the patients. Patients whose global MEQ score identified them as morning types were significantly older than those with an intermediate or evening chronotype, and they had less social jet lag. No difference in epilepsy features and treatments was found between morning-oriented and nonmorning-oriented patients. Our analyses showed that the patients with epilepsy tended to be morning-oriented and to perceive themselves as morning types, even though this was not reflected in their DLMO values which did not differ significantly from those of controls and mostly fell within the intermediate chronotype range. Several factors may considerably influence subjective chronotype. We speculate that, in patients with epilepsy, the disease itself, prompting certain lifestyle choices, including a regular sleep schedule and

  19. Cognitive Behavioral Therapy vs. Tai Chi for Late Life Insomnia and Inflammatory Risk: A Randomized Controlled Comparative Efficacy Trial

    PubMed Central

    Irwin, Michael R.; Olmstead, Richard; Carrillo, Carmen; Sadeghi, Nina; Breen, Elizabeth C.; Witarama, Tuff; Yokomizo, Megumi; Lavretsky, Helen; Carroll, Judith E.; Motivala, Sarosh J.; Bootzin, Richard; Nicassio, Perry

    2014-01-01

    Study Objectives: To investigate the comparative efficacy of cognitive behavioral therapy (CBT), Tai Chi Chih (TCC), and sleep seminar education control (SS) on the primary outcome of insomnia diagnosis, and secondary outcomes of sleep quality, fatigue, depressive symptoms, and inflammation in older adults with insomnia. Design: Randomized controlled, comparative efficacy trial. Setting: Los Angeles community. Patients: 123 older adults with chronic and primary insomnia. Interventions: Random assignment to CBT, TCC, or SS for 2-hour group sessions weekly over 4 months with follow-up at 7 and 16 months. Measurements: Insomnia diagnosis, patient-reported outcomes, polysomnography (PSG), and high-sensitivity C-reactive protein (CRP) levels. Results: CBT performed better than TCC and SS in remission of clinical insomnia as ascertained by a clinician (P < 0.01), and also showed greater and more sustained improvement in sleep quality, sleep parameters, fatigue, and depressive symptoms than TCC and SS (all P values < 0.01). As compared to SS, CBT was associated with a reduced risk of high CRP levels (> 3.0 mg/L) at 16 months (odds ratio [OR], 0.26 [95% CI, 0.07–0.97] P < 0.05). Remission of insomnia was associated with lower levels of CRP (P < 0.05) at 16 months. TCC was associated with improvements in sleep quality, fatigue, and depressive symptoms as compared to SS (all P's < 0.05), but not insomnia remission. PSG measures did not change. Conclusions: Treatment of late-life insomnia is better achieved and sustained by cognitive behavioral therapies. Insomnia treatment and remission reduces a marker of inflammatory risk, which has implications for cardiovascular morbidity and diabetes observed with sleep disturbance in epidemiologic surveys. Clinical Trial Registration: ClinicalTrials.gov, NCT00280020 Citation: Irwin MR, Olmstead R, Carrillo C, Sadeghi N, Breen EC, Witarama T, Yokomizo M, Lavretsky H, Carroll JE, Motivala SJ, Bootzin R, Nicassio P. Cognitive behavioral

  20. Application of high pressure processing for controlling Clostridium tyrobutyricum and late blowing defect on semi-hard cheese.

    PubMed

    Ávila, Marta; Gómez-Torres, Natalia; Delgado, David; Gaya, Pilar; Garde, Sonia

    2016-12-01

    In this study we evaluated the application of different high pressure (HP) treatments (200-500 MPa at 14 °C for 10 min) to industrial sized semi-hard cheeses on day 7, with the aim of controlling two Clostridium tyrobutyricum strains causing butyric acid fermentation and cheese late blowing defect (LBD). Clostridium metabolism and LBD appearance in cheeses were monitored by sensory (cheese swelling, cracks/splits, off-odours) and instrumental analyses (organic acids by HPLC and volatile compounds by SPME/GC-MS) after 60 days. Cheeses with clostridial spores HP-untreated and HP-treated at 200 MPa showed visible LBD symptoms, lower concentrations of lactic, citric and acetic acids, and higher levels of pyruvic, propionic and butyric acids and of 1-butanol, ethyl and methyl butanoate, and ethyl pentanoate than cheeses without spores. However, cheeses with clostridial spores and HP-treated at ≥ 300 MPa did not show LBD symptoms and their organic acids and volatile compounds profiles were comparable to those of their respective HP-treated control cheeses, despite HP treatments caused a low spore reduction. A decrease in C. tyrobutyricum spore counts was observed after curd pressing, which seems to indicate an early spore germination, suggesting that HP treatments ≥300 MPa were able to inactivate the emerged C. tyrobutyricum vegetative cells and, thereby, prevent LBD.

  1. Hg concentrations from Late Triassic and Early Jurassic sedimentary rocks: first order similarities and second order depositional and diagenetic controls

    NASA Astrophysics Data System (ADS)

    Yager, J. A.; West, A. J.; Bergquist, B. A.; Thibodeau, A. M.; Corsetti, F. A.; Berelson, W.; Bottjer, D. J.; Rosas, S.

    2016-12-01

    Mercury concentrations in sediments have recently gained prominence as a potential tool for identifying large igneous province (LIP) volcanism in sedimentary records. LIP volcanism coincides with several mass extinctions during the Phanerozoic, but it is often difficult to directly tie LIP activity with the record of extinction in marine successions. Here, we build on mercury concentration data reported by Thibodeau et al. (Nature Communications, 7:11147, 2016) from the Late Triassic and Early Jurassic of New York Canyon, Nevada, USA. Increases in Hg concentrations in that record were attributed to Central Atlantic Magmatic Province (CAMP) activity in association with the end-Triassic mass extinction. We expand the measured section from New York Canyon and report new mercury concentrations from Levanto, Peru, where dated ash beds provide a discrete chronology, as well as St. Audrie's Bay, UK, a well-studied succession. We correlate these records using carbon isotopes and ammonites and find similarities in the onset of elevated Hg concentrations and Hg/TOC in association with changes in C isotopes. We also find second order patterns that differ between sections and may have depositional and diagenetic controls. We will discuss these changes within a sedimentological framework to further understand the controls on Hg concentrations in sedimentary records and their implications for past volcanism.

  2. Influence of gender and age on cognitive inhibition in late-onset depression: a case-control study.

    PubMed

    Richard-Devantoy, S; Deguigne, F; Annweiler, C; Letourneau, G; Beauchet, O

    2013-11-01

    To compare cognitive inhibition performance between people with early-onset (EOD) or late-onset depression (LOD) and controls, and between women and men with LOD. On the basis of a case-control design, global executive performance (Frontal Assessment Battery); verbal (Hayling), attention (Stroop), and motor (Go/No-Go) components of cognitive inhibition; mental shifting (Trail Making Test parts A and B); and updating in working memory (Wechsler Adult Intelligence Scale) were assessed in 40 participants (10 depressed women with LOD (i.e., ≥60 years old), 10 depressed women with EOD (i.e., <60 years old), 10 healthy women and 10 depressed men with LOD (i.e., ≥60 years old)). Older depressed women, irrespective of age of depression onset, had greater cognitive inhibition impairments (attention and verbal component) compared with healthy women. LOD was significantly associated with the attention component of cognitive inhibition impairment, unlike EOD (p = 0.026). No executive differences were found regarding age of first-onset depression in older depressed women, and between women and men with LOD. Cognitive inhibition impairment, and more specifically its attention component, was the main characteristic of depression in the studied sample of older adults, independently of gender and age of depression onset. It is essential to perform similar studies in both genders in view of future tailor-made therapeutic modalities. Copyright © 2013 John Wiley & Sons, Ltd.

  3. Sublingual misoprostol plus laminaria for cervical preparation before surgical management of late first trimester missed abortions, a randomized controlled trial.

    PubMed

    Khooshideh, Maryam; Yarmohammadi, Nasim; Shahriari, Ali; Sheikh, Mahdi

    2017-02-01

    Comparing the efficacy of low-dose sublingual misoprostol plus laminaria to medium-dose sublingual misoprostol alone for cervical dilation before surgical management of late first trimester missed abortions. Randomized, controlled trial evaluated 70 women with missed abortion, admitted for surgical termination of pregnancy. The patients were randomly assigned to receive 200 μg sublingual misoprostol with cervical laminaria (intervention group) or 400 μg sublingual misoprostol without laminaria (control group), four hours before surgical process. The study is registered at www.irct.ir (IRCT2014070711020N4). More patients in the intervention group achieved the desired cervical dilation (≥Hegar7) before surgical process than the control group (91.4% versus 17.1%, p < 0.001). Patients in the intervention group experienced less pain during the waiting period (mean Visual Analog Scale scores: 30.8 ± 3.7 versus 43.7 ± 5.9, p < 0.001), and had higher satisfaction level (highly satisfied: 97.1% versus 77.1%, p = 0.02). Four patients in the intervention group and none in the control group had spontaneous expulsion of pregnancy products (p = 0.11). Compared to medium-dose sublingual misoprostol alone, using a combination of cervical laminaria plus low-dose sublingual misoprostol before surgical process is associated with significantly more effective and rapid cervical dilation, lower requirement for mechanical dilation, lower abdominal pain and discomfort during the waiting period and higher patients' satisfaction.

  4. Chronology and tectonic controls of late tertiary deposition in the southwestern Tian Shan foreland, NW China

    USGS Publications Warehouse

    Heermance, R.V.; Chen, J.; Burbank, D.W.; Wang, C.

    2007-01-01

    Magnetostratigraphy from the Kashi foreland basin along the southern margin of the Tian Shan in Western China defines the chronology of both sedimentation and the structural evolution of this collisional mountain belt. Eleven magnetostratigraphic sections representing ???13 km of basin strata provide a two- and three-dimensional record of continuous deposition since ???18 Ma. The distinctive Xiyu conglomerate makes up the uppermost strata in eight of 11 magnetostratigraphic sections within the foreland and forms a wedge that thins southward. The basal age of the conglomerate varies from 15.5??0.5 Ma at the northernmost part of the foreland, to 8.6??0.1 Ma in the central (medial) part of the foreland and to 1.9??0.2, ???1.04 and 0.7??0.1 Ma along the southern deformation front of the foreland basin. These data indicate the Xiyu conglomerate is highly time-transgressive and has prograded south since just after the initial uplift of the Kashi Basin Thrust (KBT) at 18.9??3.3 Ma. Southward progradation occurred at an average rate of ???3 mm year -1 between 15.5 and 2 Ma, before accelerating to ???10 mm year-1. Abrupt changes in sediment-accumulation rates are observed at 16.3 and 13.5 Ma in the northern part of the foreland and are interpreted to correspond to southward stepping deformation. A subtle decrease in the sedimentation rate above the Keketamu anticline is determined at ???4.0 Ma and was synchronous with an increase in sedimentation rate further south above the Atushi Anticline. Magnetostratigraphy also dates growth strata at <4.0, 1.4??0.1 and 1.4??0.2 Ma on the southern flanks the Keketamu, Atushi and Kashi anticlines, respectively. Together, sedimentation rate changes and growth strata indicate stepped migration of deformation into the Kashi foreland at least at 16.3, 13.5, 4.0 and 1.4 Ma. Progressive reconstruction of a seismically controlled cross-section through the foreland produces total shortening of 13-21 km and migration of the deformation front at

  5. Quantification of jasmonic and salicylic acids in rice seedling leaves.

    PubMed

    Cho, Kyoungwon; Han, Oksoo; Tamogami, Shigeru; Shibato, Junko; Kubo, Akihiro; Agrawal, Ganesh Kumar; Rakwal, Randeep

    2013-01-01

    Jasmonic acid (JA) and salicylic acid (SA) are critical signaling components involved in various aspects of plant growth, development, and defense. Their constitutive levels vary from plant to plant and also from tissue to tissue within the same plant. Moreover, their quantitative levels change when plant is exposed to biotic and abiotic stresses. To better understand the JA- and SA-mediated signaling and metabolic pathways, it is important to precisely quantify their levels in plants/tissues/organs. However, their extraction and quantification are not trivial and still technically challenging. An effort has been made in various laboratories to develop a simple and standard procedure that can be utilized for quantification of JA and SA. Here, we present the experimental procedure and our decade of experience on extracting and quantifying them in an absolute manner in leaves of rice seedlings. We must mention that this method has been applied to both monocotyledonous and dicotyledonous plants for absolute quantification of JA and SA. As collaboration is the key towards rapid progress in science and technology, we are always open to sharing our experience in this field with any active research group with an aim to improve the procedure further and eventually to connect the importance of their (JA and SA) quantitative levels with networks of signaling and metabolic pathways in plants.

  6. Catalases negatively regulate methyl jasmonate signaling in guard cells.

    PubMed

    Jannat, Rayhanur; Uraji, Misugi; Hossain, Mohammad Anowar; Islam, Mohammad Muzahidul; Nakamura, Yoshimasa; Mori, Izumi C; Murata, Yoshiyuki

    2012-07-01

    Methyl jasmonate (MeJA)-induced stomatal closure is accompanied by the accumulation of hydrogen peroxide (H₂O₂) in guard cells. In this study, we investigated the roles of catalases (CATs) in MeJA-induced stomatal closure using cat mutants cat2, cat3-1 and cat1 cat3, and the CAT inhibitor, 3-aminotriazole (AT). When assessed with 2',7'-dichlorodihydrofluorescein, the reduction of catalase activity by means of mutations and the inhibitor accumulated higher basal levels of H₂O₂ in guard cells whereas they did not affect stomatal aperture in the absence of MeJA. In contrast, the cat mutations and the treatment with AT potentiated MeJA-induced stomatal closure and MeJA-induced H₂O₂ production. These results indicate that CATs negatively regulate H₂O₂ accumulation in guard cells and suggest that inducible H₂O₂ production rather than constitutive elevation modulates stomatal apertures in Arabidopsis. Copyright © 2012 Elsevier GmbH. All rights reserved.

  7. Induced responses to herbivory and jasmonate in three milkweed species.

    PubMed

    Rasmann, Sergio; Johnson, M Daisy; Agrawal, Anurag A

    2009-11-01

    We studied constitutive and induced defensive traits (latex exudation, cardenolides, proteases, and C/N ratio) and resistance to monarch caterpillars (Danaus plexippus) in three closely related milkweed species (Asclepias angustifolia, A. barjoniifolia and A. fascicularis). All traits showed significant induction in at least one of the species. Jasmonate application only partially mimicked the effect of monarch feeding. We found some correspondence between latex and cardenolide content and reduced larval growth. Larvae fed cut leaves of A. angustifolia grew better than larvae fed intact plants. Addition of the cardenolide digitoxin to cut leaves reduced larval growth but ouabain (at the same concentration) had no effect. We, thus, confirm that latex and cardenolides are major defenses in milkweeds, effective against a specialist herbivore. Other traits such as proteases and C/N ratio additionally may be integrated in the defense scheme of those plants. Induction seems to play an important role in plants that have an intermediate level of defense, and we advocate incorporating induction as an additional axis of the plant defense syndrome hypothesis.

  8. Tomato linalool synthase is induced in trichomes by jasmonic acid

    PubMed Central

    van Schie, Chris C. N.; Haring, Michel A.

    2007-01-01

    Tomato (Lycopersicon esculentum) plants emit a blend of volatile organic compounds, which mainly consists of terpenes. Upon herbivory or wounding, the emission of several terpenes increases. We have identified and characterized the first two tomato monoterpene synthases, LeMTS1 and LeMTS2. Although these proteins were highly homologous, recombinant LeMTS1 protein produced (R)-linalool from geranyl diphosphate (GPP) and (E)-nerolidol from farnesyl diphosphate (FPP), while recombinant LeMTS2 produced β-phellandrene, β-myrcene, and sabinene from GPP. In addition, these genes were expressed in different tissues: LeMTS1 was expressed in flowers, young leaves, stems, and petioles, while LeMTS2 was strongest expressed in stems and roots. LeMTS1 expression in leaves was induced by spider mite-infestation, wounding and jasmonic acid (JA)-treatment, while LeMTS2 did not respond to these stimuli. The expression of LeMTS1 in stems and petioles was predominantly detected in trichomes and could be induced by JA. Because JA treatment strongly induced emission of linalool and overexpression of LeMTS1 in tomato resulted in increased production of linalool, we propose that LeMTS1 is a genuine linalool synthase. Our results underline the importance of trichomes in JA-induced terpene emission in tomato. PMID:17440821

  9. Jasmonate-induced biosynthesis of andrographolide in Andrographis paniculata.

    PubMed

    Sharma, Shiv Narayan; Jha, Zenu; Sinha, Rakesh Kumar; Geda, Arvind Kumar

    2015-02-01

    Andrographolide is a prominent secondary metabolite found in Andrographis paniculata that exhibits enormous pharmacological effects. In spite of immense value, the normal biosynthesis of andrographolide results in low amount of the metabolite. To induce the biosynthesis of andrographolide, we attempted elicitor-induced activation of andrographolide biosynthesis in cell cultures of A. paniculata. This was carried out by using methyl jasmonate (MeJA) as an elicitor. Among the various concentrations of MeJA tested at different time periods, 5 µM MeJA yielded 5.25 times more andrographolide content after 24 h of treatment. The accumulation of andrographolide was correlated with the expression level of known regulatory genes (hmgs, hmgr, dxs, dxr, isph and ggps) of mevalonic acid (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways. These results established the involvement of MeJA in andrographolide biosynthesis by inducing the transcription of its biosynthetic pathways genes. The coordination of isph, ggps and hmgs expression highly influenced the andrographolide biosynthesis.

  10. Arabidopsis class I and class II TCP transcription factors regulate jasmonic acid metabolism and leaf development antagonistically.

    PubMed

    Danisman, Selahattin; van der Wal, Froukje; Dhondt, Stijn; Waites, Richard; de Folter, Stefan; Bimbo, Andrea; van Dijk, Aalt D J; Muino, Jose M; Cutri, Lucas; Dornelas, Marcelo C; Angenent, Gerco C; Immink, Richard G H

    2012-08-01

    TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR1 (TCP) transcription factors control developmental processes in plants. The 24 TCP transcription factors encoded in the Arabidopsis (Arabidopsis thaliana) genome are divided into two classes, class I and class II TCPs, which are proposed to act antagonistically. We performed a detailed phenotypic analysis of the class I tcp20 mutant, showing an increase in leaf pavement cell sizes in 10-d-old seedlings. Subsequently, a glucocorticoid receptor induction assay was performed, aiming to identify potential target genes of the TCP20 protein during leaf development. The LIPOXYGENASE2 (LOX2) and class I TCP9 genes were identified as TCP20 targets, and binding of TCP20 to their regulatory sequences could be confirmed by chromatin immunoprecipitation analyses. LOX2 encodes for a jasmonate biosynthesis gene, which is also targeted by class II TCP proteins that are under the control of the microRNA JAGGED AND WAVY (JAW), although in an antagonistic manner. Mutation of TCP9, the second identified TCP20 target, resulted in increased pavement cell sizes during early leaf developmental stages. Analysis of senescence in the single tcp9 and tcp20 mutants and the tcp9tcp20 double mutants showed an earlier onset of this process in comparison with wild-type control plants in the double mutant only. Both the cell size and senescence phenotypes are opposite to the known class II TCP mutant phenotype in JAW plants. Altogether, these results point to an antagonistic function of class I and class II TCP proteins in the control of leaf development via the jasmonate signaling pathway.

  11. Methyl jasmonate affects phenolic metabolism and gene expression in blueberry (Vaccinium corymbosum).

    PubMed

    Cocetta, Giacomo; Rossoni, Mara; Gardana, Claudio; Mignani, Ilaria; Ferrante, Antonio; Spinardi, Anna

    2015-02-01

    Blueberry (Vaccinium corymbosum) is a fruit very much appreciated by consumers for its antioxidant potential and health-promoting traits. Its beneficial potential properties are mainly due to a high content of anthocyanins and their amount can change after elicitation with methyl jasmonate. The aim of this work is to evaluate the changes in expression of several genes, accumulation of phenolic compounds and alterations in antioxidant potential in two different blueberry cultivars ('Duke' and 'Blueray') in response to methyl jasmonate (0.1 mM). Results showed that 9 h after treatment, the expression of phenylalanine ammonium lyase, chalcone synthase and anthocyanidin synthase genes was stimulated more in the 'Blueray' variety. Among the phenols measured an increase was recorded also for epicatechin and anthocyanin concentrations. 'Duke' is a richer sourche of anthocyanins compared to 'Blueray', treatment with methyl jasmonate promoted in 'Blueray' an increase in pigments as well as in the antioxidant potential, especially in fully ripe berries, but treated 'Duke' berries had greater levels, which were not induced by methyl jasmonate treatment. In conclusion, methyl jasmonate was, in some cases, an effective elicitor of phenolic metabolism and gene expression in blueberry, though with different intensity between cultivars.

  12. Jasmonates trigger prey-induced formation of 'outer stomach' in carnivorous sundew plants.

    PubMed

    Nakamura, Yoko; Reichelt, Michael; Mayer, Veronika E; Mithöfer, Axel

    2013-05-22

    It has been widely accepted that the growth-related phytohormone auxin is the endogenous signal that initiates bending movements of plant organs. In 1875, Charles Darwin described how the bending movement of leaves in carnivorous sundew species formed an 'outer stomach' that allowed the plants to enclose and digest captured insect prey. About 100 years later, auxin was suggested to be the factor responsible for this movement. We report that prey capture induces both leaf bending and the accumulation of defence-related jasmonate phytohormones. In Drosera capensis fed with fruitflies, within 3 h after prey capture and simultaneous with leaf movement, we detected an increase in jasmonic acid and its isoleucine conjugate. This accumulation was spatially restricted to the bending segment of the leaves. The application of jasmonates alone was sufficient to trigger leaf bending. Only living fruitflies or the body fluids of crushed fruitflies induced leaf curvature; neither dead flies nor mechanical treatment had any effect. Our findings strongly suggest that the formation of the 'outer stomach' in Drosera is a chemonastic movement that is triggered by accumulation of endogenous jasmonates. These results suggest that in carnivorous sundew plants the jasmonate cascade might have been adapted to facilitate carnivory rather than to defend against herbivores.

  13. Jasmonates trigger prey-induced formation of ‘outer stomach’ in carnivorous sundew plants

    PubMed Central

    Nakamura, Yoko; Reichelt, Michael; Mayer, Veronika E.; Mithöfer, Axel

    2013-01-01

    It has been widely accepted that the growth-related phytohormone auxin is the endogenous signal that initiates bending movements of plant organs. In 1875, Charles Darwin described how the bending movement of leaves in carnivorous sundew species formed an ‘outer stomach’ that allowed the plants to enclose and digest captured insect prey. About 100 years later, auxin was suggested to be the factor responsible for this movement. We report that prey capture induces both leaf bending and the accumulation of defence-related jasmonate phytohormones. In Drosera capensis fed with fruitflies, within 3 h after prey capture and simultaneous with leaf movement, we detected an increase in jasmonic acid and its isoleucine conjugate. This accumulation was spatially restricted to the bending segment of the leaves. The application of jasmonates alone was sufficient to trigger leaf bending. Only living fruitflies or the body fluids of crushed fruitflies induced leaf curvature; neither dead flies nor mechanical treatment had any effect. Our findings strongly suggest that the formation of the ‘outer stomach’ in Drosera is a chemonastic movement that is triggered by accumulation of endogenous jasmonates. These results suggest that in carnivorous sundew plants the jasmonate cascade might have been adapted to facilitate carnivory rather than to defend against herbivores. PMID:23516244

  14. Arbuscular mycorrhizal symbiosis and methyl jasmonate avoid the inhibition of root hydraulic conductivity caused by drought.

    PubMed

    Sánchez-Romera, Beatriz; Ruiz-Lozano, Juan Manuel; Zamarreño, Ángel María; García-Mina, José María; Aroca, Ricardo

    2016-02-01

    Hormonal regulation and symbiotic relationships provide benefits for plants to overcome stress conditions. The aim of this study was to elucidate the effects of exogenous methyl jasmonate (MeJA) application on root hydraulic conductivity (L) of Phaseolus vulgaris plants which established arbuscular mycorrhizal (AM) symbiosis under two water regimes (well-watered and drought conditions). The variation in endogenous contents of several hormones (MeJA, JA, abscisic acid (ABA), indol-3-acetic acid (IAA), salicylic acid (SA)) and the changes in aquaporin gene expression, protein abundance and phosphorylation state were analyzed. AM symbiosis decreased L under well-watered conditions, which was partially reverted by the MeJA treatment, apparently by a drop in root IAA contents. Also, AM symbiosis and MeJA prevented inhibition of L under drought conditions, most probably by a reduction in root SA contents. Additionally, the gene expression of two fungal aquaporins was upregulated under drought conditions, independently of the MeJA treatment. Plant aquaporin gene expression could not explain the behaviour of L. Conversely, evidence was found for the control of L by phosphorylation of aquaporins. Hence, MeJA addition modified the response of L to both AM symbiosis and drought, presumably by regulating the root contents of IAA and SA and the phosphorylation state of aquaporins.

  15. Haemoglobin modulates salicylate and jasmonate/ethylene-mediated resistance mechanisms against pathogens

    PubMed Central

    Mur, Luis A. J.

    2012-01-01

    Nitric oxide (NO) plays a role in defence against hemibiotrophic pathogens mediated by salicylate (SA) and also necrotrophic pathogens influenced by jasmonate/ethylene (JA/Et). This study examined how NO-oxidizing haemoglobins (Hb) encoded by GLB1, GLB2, and GLB3 in Arabidopsis could influence both defence pathways. The impact of Hb on responses to the hemibiotrophic Pseudomonas syringae pathovar tomato (Pst) AvrRpm1 and the necrotrophic Botrytis cinerea were investigated using glb1, glb2, and glb3 mutant lines and also CaMV 35S GLB1 and GLB2 overexpression lines. In glb1, but not glb2 and glb3, increased resistance was observed to both pathogens but was compromised in the 35S-GLB1. A quantum cascade laser-based sensor measured elevated NO production in glb1 infected with Pst AvrRpm1 and B. cinerea, which was reduced in 35S-GLB1 compared to Col-0. SA accumulation was increased in glb1 and reduced in 35S-GLB1 compared to controls following attack by Pst AvrRpm1. Similarly, JA and Et levels were increased in glb1 but decreased in 35S-GLB1 in response to attack by B. cinerea. Quantitative PCR assays indicated reduced GLB1 expression during challenge with either pathogen, thus this may elevate NO concentration and promote a wide-ranging defence against pathogens. PMID:22641422

  16. Regulation of basal and oxidative stress-triggered jasmonic acid-related gene expression by glutathione.

    PubMed

    Han, Yi; Mhamdi, Amna; Chaouch, Sejir; Noctor, Graham

    2013-06-01

    Glutathione is a determinant of cellular redox state with roles in defence and detoxification. Emerging concepts suggest that this compound also has functions in cellular signalling. Here, we report evidence that glutathione plays potentially important roles in setting signalling strength through the jasmonic acid (JA) pathway. Firstly, we show that basal expression of JA-related genes is correlated with leaf glutathione content when the latter is manipulated either genetically or pharmacologically. Secondly, analyses of an oxidative stress signalling mutant, cat2, reveal that up-regulation of the JA pathway triggered by intracellular oxidation requires accompanying glutathione accumulation. Genetically blocking this accumulation in a cat2 cad2 line largely annuls H2 O2 -induced expression of JA-linked genes, and this effect can be rescued by exogenously supplying glutathione. While most attention on glutathione functions in biotic stress responses has been focused on the thiol-regulated protein NPR1, a comparison of JA-linked gene expression in cat2 cad2 and cat2 npr1 double mutants provides evidence that glutathione acts through other components to regulate the response of this pathway to oxidative stress. Our study provides new information implicating glutathione as a factor determining basal JA gene expression and suggests novel glutathione-dependent control points that regulate JA signalling in response to intracellular oxidation.

  17. Enhancement of broccoli indole glucosinolates by methyl jasmonate treatment and effects on prostate carcinogenesis.

    PubMed

    Liu, Ann G; Juvik, John A; Jeffery, Elizabeth H; Berman-Booty, Lisa D; Clinton, Steven K; Erdman, John W

    2014-11-01

    Broccoli is rich in bioactive components, such as sulforaphane and indole-3-carbinol, which may impact cancer risk. The glucosinolate profile of broccoli can be manipulated through treatment with the plant stress hormone methyl jasmonate (MeJA). Our objective was to produce broccoli with enhanced levels of indole glucosinolates and determine its impact on prostate carcinogenesis. Brassica oleracea var. Green Magic was treated with a 250 μM MeJA solution 4 days prior to harvest. MeJA-treated broccoli had significantly increased levels of glucobrassicin, neoglucobrassicin, and gluconasturtiin (P < .05). Male transgenic adenocarcinoma of mouse prostate (TRAMP) mice (n = 99) were randomized into three diet groups at 5-7 weeks of age: AIN-93G control, 10% standard broccoli powder, or 10% MeJA broccoli powder. Diets were fed throughout the study until termination at 20 weeks of age. Hepatic CYP1A was induced with MeJA broccoli powder feeding, indicating biological activity of the indole glucosinolates. Following ∼ 15 weeks on diets, neither of the broccoli treatments significantly altered genitourinary tract weight, pathologic score, or metastasis incidence, indicating that broccoli powder at 10% of the diet was ineffective at reducing prostate carcinogenesis in the TRAMP model. Whereas broccoli powder feeding had no effect in this model of prostate cancer, our work demonstrates the feasibility of employing plant stress hormones exogenously to stimulate changes in phytochemical profiles, an approach that may be useful for optimizing bioactive component patterns in foods for chronic-disease-prevention studies.

  18. Metabolomic analysis of phenolic compounds in buckwheat (Fagopyrum esculentum M.) sprouts treated with methyl jasmonate.

    PubMed

    Kim, Hyun-Jin; Park, Kee-Jai; Lim, Jeong-Ho

    2011-05-25

    The effects of exogenous methyl jasmonate (MeJA) on phytochemical production in buckwheat sprouts cultivated under dark conditions (0, 1, 3, 5, and 7 d) were investigated by metabolomic analysis, using ultra performance liquid chromatography-quadrupole-time-of-flight (UPLC-Q-TOF) mass spectroscopy (MS) and partial least-squares-discriminant analysis (PLS-DA). MeJA-treated and control groups showed no differences in growth but were clearly discriminated from each other on PLS-DA score plots. The metabolites contributing to the discrimination were assigned as chlorogenic acid, catechin, isoorientin, orientin, rutin, vitexin, and quercitrin, which have various health effects. Moreover, isoorientin, orientin, rutin, and vitexin were assigned as the main phytochemicals of sprouts cultivated under dark conditions. The accumulation of these metabolites caused the phenolic compound content and antioxidant activity of the sprouts to increase. Further, this study revealed that their accumulation resulted from the stimulation of the phenylpropanoid pathway by MeJA treatment. Therefore, these metabolites may be useful for better understanding the effects of MeJA on buckwheat sprout phytochemicals and contribute to improving the functional quality of the sprouts.

  19. Jasmonic acid protects etiolated seedlings of Arabidopsis thaliana against herbivorous arthropods

    PubMed Central

    Boex-Fontvieille, Edouard; Rustgi, Sachin; Von Wettstein, Diter; Pollmann, Stephan; Reinbothe, Steffen; Reinbothe, Christiane

    2016-01-01

    ABSTRACT Seed predators can cause mass ingestion of larger seed populations. As well, herbivorous arthropods attempt to attack etiolated seedlings and chose the apical hook for ingestion, aimed at dropping the cotyledons for later consumption. Etiolated seedlings, as we show here, have established an efficient mechanism of protecting their Achilles' heel against these predators, however. Evidence is provided for a role of jasmonic acid (JA) in this largely uncharacterized plant-herbivore interaction during skotomorphogenesis and that this comprises the temporally and spatially tightly controlled synthesis of a cysteine protease inhibitors of the Kunitz family. Interestingly, the same Kunitz protease inhibitor was found to be expressed in flowers of Arabidopsis where endogenous JA levels are high for fertility. Because both the apical hook and inflorescences were preferred isopod targets in JA-deficient plants that could be rescued by exogenously administered JA, our data identify a JA-dependent mechanism of plant arthropod deterrence that is recalled in different organs and at quite different times of plant development. PMID:27485473

  20. Jasmonic acid protects etiolated seedlings of Arabidopsis thaliana against herbivorous arthropods.

    PubMed

    Boex-Fontvieille, Edouard; Rustgi, Sachin; Von Wettstein, Diter; Pollmann, Stephan; Reinbothe, Steffen; Reinbothe, Christiane

    2016-08-02

    Seed predators can cause mass ingestion of larger seed populations. As well, herbivorous arthropods attempt to attack etiolated seedlings and chose the apical hook for ingestion, aimed at dropping the cotyledons for later consumption. Etiolated seedlings, as we show here, have established an efficient mechanism of protecting their Achilles' heel against these predators, however. Evidence is provided for a role of jasmonic acid (JA) in this largely uncharacterized plant-herbivore interaction during skotomorphogenesis and that this comprises the temporally and spatially tightly controlled synthesis of a cysteine protease inhibitors of the Kunitz family. Interestingly, the same Kunitz protease inhibitor was found to be expressed in flowers of Arabidopsis where endogenous JA levels are high for fertility. Because both the apical hook and inflorescences were preferred isopod targets in JA-deficient plants that could be rescued by exogenously administered JA, our data identify a JA-dependent mechanism of plant arthropod deterrence that is recalled in different organs and at quite different times of plant development.

  1. Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA).

    PubMed

    Gao, Zhengquan; Li, Yan; Wu, Guanxun; Li, Guoqiang; Sun, Haifeng; Deng, Suzhen; Shen, Yicheng; Chen, Guoqiang; Zhang, Ruihao; Meng, Chunxiao; Zhang, Xiaowen

    2015-01-01

    Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis.

  2. (+)-methyl jasmonate-induced bioformation of myricetin, quercetin and kaempferol in red raspberries.

    PubMed

    de la Peña Moreno, Fernando; Blanch, Gracia Patricia; Ruiz del Castillo, Maria Luisa

    2010-11-24

    The effect of postharvest treatment with enantiomers of methyl jasmonate (MJ) in conjunction with ethanol on bioformation of myricetin, quercetin and kaempferol in red raspberry was studied. For comparison, postharvest treatment with the commercial stereoisomeric mixture of MJ in conjunction with ethanol was simultaneously accomplished. The levels obtained were contrasted with those determined in untreated (control) samples. Exogenous (+)-MJ induced an enhancement in the levels of myricetin, quercetin and, particularly, kaempferol whereas the exposition to (-)-MJ exhibited the opposite effect. Enzymatic assays were carried out in presence and absence of (-)-MJ and (+)-MJ to evaluate possible changes in the activity of the enzymes regulating the bioformation of flavonols in red raspberries as a consequence of the treatments. From the results of the assays both (-)-MJ and (+)-MJ inhibited the activity of flavanone 3β-hydroxylase (FHT) and flavonol synthase (FLS), which are directly involved in the formation of flavonols from (-/+)-naringenin. From these results, it is speculated that the activity of phenylalanine ammonia lyase (PAL) regulating the formation of (-/+)-naringenin from l-phenylalanine by (+)-MJ in conjunction with ethanol is promoted. Postharvest treatment of red raspberry with (+)-MJ in ethanol is proposed as a mean to increase flavonol content in red raspberries.

  3. Haemoglobin modulates salicylate and jasmonate/ethylene-mediated resistance mechanisms against pathogens.

    PubMed

    Mur, Luis A J; Sivakumaran, Anushen; Mandon, Julien; Cristescu, Simona M; Harren, Frans J M; Hebelstrup, Kim H

    2012-07-01

    Nitric oxide (NO) plays a role in defence against hemibiotrophic pathogens mediated by salicylate (SA) and also necrotrophic pathogens influenced by jasmonate/ethylene (JA/Et). This study examined how NO-oxidizing haemoglobins (Hb) encoded by GLB1, GLB2, and GLB3 in Arabidopsis could influence both defence pathways. The impact of Hb on responses to the hemibiotrophic Pseudomonas syringae pathovar tomato (Pst) AvrRpm1 and the necrotrophic Botrytis cinerea were investigated using glb1, glb2, and glb3 mutant lines and also CaMV 35S GLB1 and GLB2 overexpression lines. In glb1, but not glb2 and glb3, increased resistance was observed to both pathogens but was compromised in the 35S-GLB1. A quantum cascade laser-based sensor measured elevated NO production in glb1 infected with Pst AvrRpm1 and B. cinerea, which was reduced in 35S-GLB1 compared to Col-0. SA accumulation was increased in glb1 and reduced in 35S-GLB1 compared to controls following attack by Pst AvrRpm1. Similarly, JA and Et levels were increased in glb1 but decreased in 35S-GLB1 in response to attack by B. cinerea. Quantitative PCR assays indicated reduced GLB1 expression during challenge with either pathogen, thus this may elevate NO concentration and promote a wide-ranging defence against pathogens.

  4. Targeted and Untargeted Approaches Unravel Novel Candidate Genes and Diagnostic SNPs for Quantitative Resistance of the Potato (Solanum tuberosum L.) to Phytophthora infestans Causing the Late Blight Disease.

    PubMed

    Mosquera, Teresa; Alvarez, Maria Fernanda; Jiménez-Gómez, José M; Muktar, Meki Shehabu; Paulo, Maria João; Steinemann, Sebastian; Li, Jinquan; Draffehn, Astrid; Hofmann, Andrea; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhardt; Walkemeier, Birgit; Gebhardt, Christiane

    2016-01-01

    The oomycete Phytophthora infestans causes late blight of potato, which can completely destroy the crop. Therefore, for the past 160 years, late blight has been the most important potato disease worldwide. The identification of cultivars with high and durable field resistance to P. infestans is an objective of most potato breeding programs. This type of resistance is polygenic and therefore quantitative. Its evaluation requires multi-year and location trials. Furthermore, quantitative resistance to late blight correlates with late plant maturity, a negative agricultural trait. Knowledge of the molecular genetic basis of quantitative resistance to late blight not compromised by late maturity is very limited. It is however essential for developing diagnostic DNA markers that facilitate the efficient combination of superior resistance alleles in improved cultivars. We used association genetics in a population of 184 tetraploid potato cultivars in order to identify single nucleotide polymorphisms (SNPs) that are associated with maturity corrected resistance (MCR) to late blight. The population was genotyped for almost 9000 SNPs from three different sources. The first source was candidate genes specifically selected for their function in the jasmonate pathway. The second source was novel candidate genes selected based on comparative transcript profiling (RNA-Seq) of groups of genotypes with contrasting levels of quantitative resistance to P. infestans. The third source was the first generation 8.3k SolCAP SNP genotyping array available in potato for genome wide association studies (GWAS). Twenty seven SNPs from all three sources showed robust association with MCR. Some of those were located in genes that are strong candidates for directly controlling quantitative resistance, based on functional annotation. Most important were: a lipoxygenase (jasmonate pathway), a 3-hydroxy-3-methylglutaryl coenzyme A reductase (mevalonate pathway), a P450 protein (terpene biosynthesis

  5. Targeted and Untargeted Approaches Unravel Novel Candidate Genes and Diagnostic SNPs for Quantitative Resistance of the Potato (Solanum tuberosum L.) to Phytophthora infestans Causing the Late Blight Disease

    PubMed Central

    Jiménez-Gómez, José M.; Muktar, Meki Shehabu; Paulo, Maria João; Steinemann, Sebastian; Li, Jinquan; Draffehn, Astrid; Hofmann, Andrea; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhardt; Walkemeier, Birgit; Gebhardt, Christiane

    2016-01-01

    The oomycete Phytophthora infestans causes late blight of potato, which can completely destroy the crop. Therefore, for the past 160 years, late blight has been the most important potato disease worldwide. The identification of cultivars with high and durable field resistance to P. infestans is an objective of most potato breeding programs. This type of resistance is polygenic and therefore quantitative. Its evaluation requires multi-year and location trials. Furthermore, quantitative resistance to late blight correlates with late plant maturity, a negative agricultural trait. Knowledge of the molecular genetic basis of quantitative resistance to late blight not compromised by late maturity is very limited. It is however essential for developing diagnostic DNA markers that facilitate the efficient combination of superior resistance alleles in improved cultivars. We used association genetics in a population of 184 tetraploid potato cultivars in order to identify single nucleotide polymorphisms (SNPs) that are associated with maturity corrected resistance (MCR) to late blight. The population was genotyped for almost 9000 SNPs from three different sources. The first source was candidate genes specifically selected for their function in the jasmonate pathway. The second source was novel candidate genes selected based on comparative transcript profiling (RNA-Seq) of groups of genotypes with contrasting levels of quantitative resistance to P. infestans. The third source was the first generation 8.3k SolCAP SNP genotyping array available in potato for genome wide association studies (GWAS). Twenty seven SNPs from all three sources showed robust association with MCR. Some of those were located in genes that are strong candidates for directly controlling quantitative resistance, based on functional annotation. Most important were: a lipoxygenase (jasmonate pathway), a 3-hydroxy-3-methylglutaryl coenzyme A reductase (mevalonate pathway), a P450 protein (terpene biosynthesis

  6. Circadian Stress Regimes Affect the Circadian Clock and Cause Jasmonic Acid-Dependent Cell Death in Cytokinin-Deficient Arabidopsis Plants[OPEN

    PubMed Central

    Nitschke, Silvia; Cortleven, Anne; Iven, Tim; Havaux, Michel; Schmülling, Thomas

    2016-01-01

    The circadian clock helps plants measure daylength and adapt to changes in the day-night rhythm. We found that changes in the light-dark regime triggered stress responses, eventually leading to cell death, in leaves of Arabidopsis thaliana plants with reduced cytokinin levels or defective cytokinin signaling. Prolonged light treatment followed by a dark period induced stress and cell death marker genes while reducing photosynthetic efficiency. This response, called circadian stress, is also characterized by altered expression of clock and clock output genes. In particular, this treatment strongly reduced the expression of CIRCADIAN CLOCK ASSOCIATED1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY). Intriguingly, similar changes in gene expression and cell death were observed in clock mutants lacking proper CCA1 and LHY function. Circadian stress caused strong changes in reactive oxygen species- and jasmonic acid (JA)-related gene expression. The activation of the JA pathway, involving the accumulation of JA metabolites, was crucial for the induction of cell death, since the cell death phenotype was strongly reduced in the jasmonate resistant1 mutant background. We propose that adaptation to circadian stress regimes requires a normal cytokinin status which, acting primarily through the AHK3 receptor, supports circadian clock function to guard against the detrimental effects of circadian stress. PMID:27354555

  7. Circadian Stress Regimes Affect the Circadian Clock and Cause Jasmonic Acid-Dependent Cell Death in Cytokinin-Deficient Arabidopsis Plants.

    PubMed

    Nitschke, Silvia; Cortleven, Anne; Iven, Tim; Feussner, Ivo; Havaux, Michel; Riefler, Michael; Schmülling, Thomas

    2016-07-01

    The circadian clock helps plants measure daylength and adapt to changes in the day-night rhythm. We found that changes in the light-dark regime triggered stress responses, eventually leading to cell death, in leaves of Arabidopsis thaliana plants with reduced cytokinin levels or defective cytokinin signaling. Prolonged light treatment followed by a dark period induced stress and cell death marker genes while reducing photosynthetic efficiency. This response, called circadian stress, is also characterized by altered expression of clock and clock output genes. In particular, this treatment strongly reduced the expression of CIRCADIAN CLOCK ASSOCIATED1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY). Intriguingly, similar changes in gene expression and cell death were observed in clock mutants lacking proper CCA1 and LHY function. Circadian stress caused strong changes in reactive oxygen species- and jasmonic acid (JA)-related gene expression. The activation of the JA pathway, involving the accumulation of JA metabolites, was crucial for the induction of cell death, since the cell death phenotype was strongly reduced in the jasmonate resistant1 mutant background. We propose that adaptation to circadian stress regimes requires a normal cytokinin status which, acting primarily through the AHK3 receptor, supports circadian clock function to guard against the detrimental effects of circadian stress. © 2016 American Society of Plant Biologists. All rights reserved.

  8. Barriers to enrollment in a randomized controlled trial of hydrocortisone for cardiovascular insufficiency in term and late preterm newborn infants.

    PubMed

    Watterberg, K L; Fernandez, E; Walsh, M C; Truog, W E; Stoll, B J; Sokol, G M; Kennedy, K A; Fraga, M V; Beauman, S S; Carper, B; Das, A; Duncan, A F; Buss, W F; Gauldin, C; Lacy, C B; Sanchez, P J; Chawla, S; Lakshminrusimha, S; Cotten, C M; Van Meurs, K P; Poindexter, B B; Bell, E F; Carlo, W A; Devaskar, U; Wyckoff, M H; Higgins, R D

    2017-09-07

    To analyze reasons for low enrollment in a randomized controlled trial (RCT) of the effect of hydrocortisone for cardiovascular insufficiency on survival without neurodevelopmental impairment (NDI) in term/late preterm newborns. The original study was a multicenter RCT. Eligibility: ⩾34 weeks' gestation, <72 h old, mechanically ventilated, receiving inotrope. Primary outcome was NDI at 2 years; infants with diagnoses at high risk for NDI were excluded. This paper presents an analysis of reasons for low patient enrollment. Two hundred and fifty-seven of the 932 otherwise eligible infants received inotropes; however, 207 (81%) had exclusionary diagnoses. Only 12 infants were randomized over 10 months; therefore, the study was terminated. Contributing factors included few eligible infants after exclusions, open-label steroid therapy and a narrow enrollment window. Despite an observational study to estimate the population, very few infants were enrolled. Successful RCTs of emergent therapy may require fewer exclusions, a short-term primary outcome, waiver of consent and/or other alternatives.Journal of Perinatology advance online publication, 7 September 2017; doi:10.1038/jp.2017.131.

  9. Climate and Fuel Controls on North American Paleofires: Smoldering to Flaming in the Late-Glacial-Holocene Transition

    NASA Technical Reports Server (NTRS)

    Han, Y. M.; Peteet, D. M.; Arimoto, R.; Cao, J. J.; An, Z. S.; Sritrairat, S.; Yan, B. Z.

    2016-01-01

    Smoldering and flaming fires, which emit different proportions of organic (OC) and black carbon (BC, in the form of char and soot), have long been recognized in modern wildfire observations but never in a paleo-record, and little is known about their interactions with climate. Here we show that in the late glacial-early Holocene transition period, when the climate was moist, relatively high quantities of char were deposited in Linsley Pond, Connecticut, USA while soot was more abundant during the warmer and drier early Holocene interval. The highest soot mass accumulation rates (MARs) occurred at the beginning of the Holocene as fuel availability increased through the climatic transition when boreal forests were locally extirpated. These variations with time are related to the different formation pathways of char and soot, which are governed by combustion efficiency. This study provides an approach for differentiating smoldering from flaming combustion in paleo-wildfire reconstructions. Our results suggest that climate and fuel loads control the occurrence of different wildfire types and precipitation may play a key role.

  10. Climate and Fuel Controls on North American Paleofires: Smoldering to Flaming in the Late-glacial-Holocene Transition.

    PubMed

    Han, Y M; Peteet, D M; Arimoto, R; Cao, J J; An, Z S; Sritrairat, S; Yan, B Z

    2016-02-10

    Smoldering and flaming fires, which emit different proportions of organic (OC) and black carbon (BC, in the form of char and soot), have long been recognized in modern wildfire observations but never in a paleo-record, and little is known about their interactions with climate. Here we show that in the late glacial-early Holocene transition period, when the climate was moist, relatively high quantities of char were deposited in Linsley Pond, Connecticut, USA while soot was more abundant during the warmer and drier early Holocene interval. The highest soot mass accumulation rates (MARs) occurred at the beginning of the Holocene as fuel availability increased through the climatic transition when boreal forests were locally extirpated. These variations with time are related to the different formation pathways of char and soot, which are governed by combustion efficiency. This study provides an approach for differentiating smoldering from flaming combustion in paleo-wildfire reconstructions. Our results suggest that climate and fuel loads control the occurrence of different wildfire types and precipitation may play a key role.

  11. Climate and Fuel Controls on North American Paleofires: Smoldering to Flaming in the Late-glacial-Holocene Transition

    PubMed Central

    Han, Y.M.; Peteet, D.M.; Arimoto, R.; Cao, J.J.; An, Z.S.; Sritrairat, S.; Yan, B.Z.

    2016-01-01

    Smoldering and flaming fires, which emit different proportions of organic (OC) and black carbon (BC, in the form of char and soot), have long been recognized in modern wildfire observations but never in a paleo-record, and little is known about their interactions with climate. Here we show that in the late glacial-early Holocene transition period, when the climate was moist, relatively high quantities of char were deposited in Linsley Pond, Connecticut, USA while soot was more abundant during the warmer and drier early Holocene interval. The highest soot mass accumulation rates (MARs) occurred at the beginning of the Holocene as fuel availability increased through the climatic transition when boreal forests were locally extirpated. These variations with time are related to the different formation pathways of char and soot, which are governed by combustion efficiency. This study provides an approach for differentiating smoldering from flaming combustion in paleo-wildfire reconstructions. Our results suggest that climate and fuel loads control the occurrence of different wildfire types and precipitation may play a key role. PMID:26860820

  12. Climate and Fuel Controls on North American Paleofires: Smoldering to Flaming in the Late-glacial-Holocene Transition

    NASA Astrophysics Data System (ADS)

    Han, Y. M.; Peteet, D. M.; Arimoto, R.; Cao, J. J.; An, Z. S.; Sritrairat, S.; Yan, B. Z.

    2016-02-01

    Smoldering and flaming fires, which emit different proportions of organic (OC) and black carbon (BC, in the form of char and soot), have long been recognized in modern wildfire observations but never in a paleo-record, and little is known about their interactions with climate. Here we show that in the late glacial-early Holocene transition period, when the climate was moist, relatively high quantities of char were deposited in Linsley Pond, Connecticut, USA while soot was more abundant during the warmer and drier early Holocene interval. The highest soot mass accumulation rates (MARs) occurred at the beginning of the Holocene as fuel availability increased through the climatic transition when boreal forests were locally extirpated. These variations with time are related to the different formation pathways of char and soot, which are governed by combustion efficiency. This study provides an approach for differentiating smoldering from flaming combustion in paleo-wildfire reconstructions. Our results suggest that climate and fuel loads control the occurrence of different wildfire types and precipitation may play a key role.

  13. Cognitive development in very vs. moderately to late preterm and full-term children: can effortful control account for group differences in toddlerhood?

    PubMed

    Voigt, Babett; Pietz, Joachim; Pauen, Sabina; Kliegel, Matthias; Reuner, Gitta

    2012-05-01

    Preterm birth is thought to have an adverse impact on cognitive development and self-regulation. Examining the effect of very vs. moderately to late premature birth on cognitive development and effortful control, as well as evaluating whether effortful control explains the link between preterm birth and poorer cognitive development. Fifty-eight very preterm children (<32 weeks gestation or <1500 g birth weight), 88 moderately to late preterm children (≥32 weeks gestation and ≥1500 birth weight) and 86 full-term children (≥38 weeks gestation and ≥2500 g birth weight) were examined at the corrected age of 24 months. Observational and parent-report measures of effortful control as well as the Bayley Scales of Infant Development II (BSID II, Mental Scale) as a measurement of cognitive development were analyzed. Very preterm and moderately to late preterm children showed significantly lower cognitive performance compared to full-term children. Lower effortful control scores (on observational measures, but not on parent-reports) were merely found for very preterm children compared to full-term children. Observational measures of effortful control partially mediated the effects of very preterm birth on cognitive performance, but did not explain the effects of moderately to late preterm birth on cognitive performance. Preterm birth in general is related to poorer cognitive performance in toddlerhood. In addition, effortful control mediates the effects of very preterm birth on cognitive development. Findings suggest that different mechanisms link moderately to late premature birth to poor cognitive development. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Factors controlling late Cenozoic continental margin growth from the Ebro Delta to the western Mediterranean deep sea

    USGS Publications Warehouse

    Nelson, C.H.; Maldonado, A.

    1990-01-01

    The Ebro continental margin sedimentation system originated with a Messinian fluvial system. This system eroded both a major subaerial canyon cutting the margin southeastward from the present Ebro Delta and an axial valley that drained northeastward down Valencia Trough. Post-Messinian submergence of this topography and the Pliocene regime of high sea levels resulted in a marine hemipelagic drape over the margin. Late Pliocene to Pleistocene glacial climatic cycles, drainagebasin deforestation, and sea-level lowstands combined to increase sediment supply, cause the margin to prograde, and create a regime of lowstand sediment-gravity flows in the deeper margin. The depositional patterns of regressive, transgressive and highstand sea-level regimes suggest that location of the sediment source near the present Ebro Delta throughout the late Cenozoic, southward current advection of sediment, and greater subsidence in the southern margin combined to cause generally asymmetric progradation of the margin to the southeast. Thicker, less stable deposits filling the Messinian subaerial canyon underwent multiple retrograde failures, eroded wide gullied canyons and formed unchanneled base-of-slope sediment aprons in the central margin area; other margin areas to the north and south developed a series of channel-levee complexes. On the basin floor, the formation of Valencia Valley over the Messinian subaerial valley and earlier faults led to draining of about 20% of the Ebro Pleistocene sediment from channel-levee complexes through the valley to prograde Valencia Fan as much as 500 km northeast of the margin. Thus, the Ebro margin has two growth directions, mainly southeastward during higher sea levels, and eastward to northeastward during lower sea levels. The northeastward draining of turbidity currents has produced unusually thin and widely dispersed turbidite systems compared to those on ponded basin floors. During the past few centuries, man's impact has exceeded natural

  15. Do Periodic Plate Reorganisations Control Late-stage Volcanism across a Broad Galápagos Hotspot?

    NASA Astrophysics Data System (ADS)

    O'Connor, J. M.; Hoernle, K.; Wijbrans, J. R.; Werner, R.; Hauff, S. F.; Stoffers, P.

    2010-12-01

    Much of the Galápagos Volcanic Province (GVP), consisting of the Cocos, Carnegie, Coiba and Malpelo aseismic ridges and related seamount provinces, remains poorly understood due to a lack of direct age and geochemical data. In recent years reconnaissance dredge/grab sampling of these submerged regions of the GVP provides some new insights that can be re-evaluated in the context of the three new cruises to the region in 2010. The distribution of 40Ar/39Ar basement ages [1-3] suggest that volcanism migrated time-progressively across GVP in broad regions of long-lived, possible concurrent, hotspot volcanism. Development of the GVP via such broad zones of overlapping volcanism leads to multiple phases of volcanism post-dating the onset of hotspot volcanism, similar to rejuvenescent volcanism that occurs million years after the main shield-building phase of mid-plate oceanic volcano, most notably along the Hawaiian-Emperor Seamount Chain. Evidence for rejuvenescent volcanism across the GVP provides an opportunity to evaluate this poorly understood process in a very different physical setting compared to the Hawaiian-Emperor Chain (mid-plate versus on/near spreading axis). Widespread episodes of coeval GVP volcanism show that the Galápagos hotspot influences broad regions of the lithosphere implying relative motion between the Cocos and Nazca plates and a broad Galápagos hotspot. The complex spreading history of the Cocos-Nazca spreading centre likely controlled the relative distribution of GVP volcanism between the Cocos and Nazca plates while creating lithosphere of variable age/thickness across the region [3]. But recent age and geochemical studies of other hotspot systems show that lithosphere influenced in the past by hotspot activity is more likely to generate late-stage volcanism in response to changing patterns of stress in the lithosphere. Late stage volcanism across a broad Galápagos hotspot might therefore reflect periodic reorganisations of the Gal

  16. Paleoclimate controls on late paleozoic sedimentation and peat formation in the central appalachian basin (U.S.A.)

    USGS Publications Warehouse

    Cecil, C.B.; Stanton, R.W.; Neuzil, S.G.; Dulong, F.T.; Ruppert, L.F.; Pierce, B.S.

    1985-01-01

    In the central Appalachian basin, at least two major climate changes affected sedimentation during the late Paleozoic. Stratigraphically, these two changes are indicated by the distribution of coal beds, the variation in coal quality, and the variation in rock lithologies. In latest Mississippian or earliest Pennsylvanian time, the climate changed from dry-seasonal tropical to ever-wet (equable) tropical. The equable climate prevailed into the Middle Pennsylvanian, influencing the morphology and geochemistry in peat-forming environments. Many of the peat deposits, which formed under the equable climate, were probably domed (raised bogs); low concentrations of dissolved solids in peat formation water resulted in low buffering capacity. Organic acids caused acidic (pH < 4), antiseptic conditions that resulted in intense leaching of mineral matter, minimal degradation of organic matter, and low-ash and low-sulfur peat deposits; the resulting coal beds are also low in ash and sulfur. Associated rocks are noncalcareous and consist of sequences of interbedded shale, siltstone, and sandstone including quartz arenite. Another climate change occurred in late Middle Pennsylvanian time when evapopation periodically exceeded rainfall resulting in an increase of both dissolved solids and pH (4 to ??? 7) in surface and near-surface water. Throughout the remainder of the Pennsylvanian, the surfaces of peat deposits were probably planar (not domed); water in peat-forming and other depositional environments became more nearly neutral. The coal beds derived from these peats are highly variable in both ash and sulfur contents. Drier or more seasonal climates are also indicated by sequences of (1) calcareous sandstone and shale, (2) nonmarine limestone that shows shallow-water and subaerial exposure features, and (3) calcareous paleosols that have caliche characteristics. Our data and observations indicate that physical depositional environment models for the origin of coal do not

  17. Serum influences the expression of Pseudomonas aeruginosa quorum-sensing genes and QS-controlled virulence genes during early and late stages of growth

    PubMed Central

    Kruczek, Cassandra; Qaisar, Uzma; Colmer-Hamood, Jane A; Hamood, Abdul N

    2014-01-01

    In response to diverse environmental stimuli at different infection sites, Pseudomonas aeruginosa, a serious nosocomial pathogen, coordinates the production of different virulence factors through a complicated network of the hierarchical quorum-sensing (QS) systems including the las, rhl, and the 2-alkyl-4-quinolone-related QS systems. We recently showed that at early stages of growth serum alters the expression of numerous P. aeruginosa genes. In this study, we utilized transcriptional analysis and enzyme assays to examine the effect of serum on the QS and QS-controlled virulence factors during early and late phases of growth of the P. aeruginosa strain PAO1. At early phase, serum repressed the transcription of lasI, rhlI, and pqsA but not lasR or rhlR. However, at late phase, serum enhanced the expression of all QS genes. Serum produced a similar effect on the synthesis of the autoinducers 3OC12-HSL, C4-HSL, and HHQ/PQS. Additionally, serum repressed the expression of several QS-controlled genes in the early phase, but enhanced them in the late phase. Furthermore, serum influenced the expression of different QS-positive (vqsR, gacA, and vfr) as well as QS-negative (rpoN, qscR, mvaT, and rsmA) regulatory genes at either early or late phases of growth. However, with the exception of PAOΔvfr, we detected comparable levels of lasI/lasR expression in PAO1 and PAO1 mutants defective in these regulatory genes. At late stationary phase, serum failed to enhance lasI/lasR expression in PAOΔvfr. These results suggest that depending on the phase of growth, serum differentially influenced the expression of P. aeruginosa QS and QS-controlled virulence genes. In late phase, serum enhanced the expression of las genes through vfr. PMID:24436158

  18. [Embryonic and Larval Development of the Asian Seabass Lates calcarifer (Pisces: Perciformes: Latidae) under Thermostatically Controlled Conditions].

    PubMed

    Shadrin, A M; Pavlov, D S

    2015-01-01

    Material for this study was obtained from the hatchery with brood stock of Lates calcarifer that originated from a natural population living in inshore waters off Central Vietnam. Commercial interest in L. calcarifer as an object of mariculture and wildstock fishery has resulted in several publications on its early life history; nevertheless, comprehensive description of early development of L. calcarifer based on controlled incubation of embryos and larvae has remained absent. In the present paper embryonic and larval development to the stage of anlage of pelvic fins is described in detail and illustrated with original drawings of live material on the basis of thermostatically controlled incubation of embryos at 27°C and larvae at 26.8°C (26.5-28.0°C). The first cleavage furrow appeared at the age of 33.5 min. The duration of synchronous cleavage cycle was 16 min. About 80% of all embryos hatched at the age of 18 h. The length of newly hatched larva during the first hour after emergence from the egg shell was 1.63 ± 0.016 mm (1.50-1.75 mm). Chronology of development of the organs, early circulatory system, and pigmentation pattern is given. The dynamics of change in the trunk and caudal body segment number in larva from hatching to the moment of anlage of pelvic fins is shown. The total number of body segments reached the maximum value of 26-27 soon after hatching and then decreased to 20-21 segments. Newly received data are discussed in a comparative context of development of some other teleosts.

  19. Extracellular volume fraction in dilated cardiomyopathy patients without obvious late gadolinium enhancement: comparison with healthy control subjects.

    PubMed

    Hong, Yoo Jin; Park, Chul Hwan; Kim, Young Jin; Hur, Jin; Lee, Hye-Jeong; Hong, Sae Rom; Suh, Young Joo; Greiser, Andreas; Paek, Mun Young; Choi, Byoung Wook; Kim, Tae Hoon

    2015-06-01

    To evaluate whether the extracellular volume fraction (ECV) measured using cardiac magnetic resonance (CMR) imaging can detect myocardial tissue changes in dilated cardiomyopathy (DCM) without late gadolinium enhancement (LGE). Forty-one DCM patients and 10 healthy volunteers underwent pre- and post-T1 mapping using a modified Look-Locker Inversion recovery sequence, LGE, and cine MRI on a 3-T CMR system. LGE-MR findings were used to divide DCM patients into two groups: Group A had no apparent LGE, and Group B had LGE apparent in at least one segment. The ECV of the left ventricle (LV) myocardium (16 segments) was calculated in the short-axis view as follows: ECV = [(ΔR1 of myocardium/ΔR1 of LV blood pool)] × (1 - hematocrit), where R1 = 1/T1, ΔR1 = post-contrast R1 - pre-contrast R1. The LV ejection fraction (LVEF) was obtained from cine MRI images. The mean myocardial ECV in LGE (-) segments in Group A + B was compared to that of controls. The mean myocardial ECV in Group A was compared to that of LGE (-) segments in Group B. The correlation between LV systolic function and the mean myocardial ECV of the whole myocardium was evaluated in all groups. Among the 41 DCM patients, 22 were in Group A, and 19 were in Group B. The mean ECV of DCM patents (n = 41, 568 segments, 30.7 % ± 5.9) was significantly higher (P < 0.001) than that of the control group (n = 10, 157 segments, 25.6 % ± 3.2). The ECV was inversely related to LVEF in Group A (r = -0.551, P = 0.008), Group B (r = -0.525, P = 0.021), and Group A + B (r = -0.550, P < 0.001). The ECV measured by MRI could be a useful parameter in evaluating diffuse myocardial changes in DCM patients.

  20. Cognitive behavioral therapy vs. Tai Chi for late life insomnia and inflammatory risk: a randomized controlled comparative efficacy trial.

    PubMed

    Irwin, Michael R; Olmstead, Richard; Carrillo, Carmen; Sadeghi, Nina; Breen, Elizabeth C; Witarama, Tuff; Yokomizo, Megumi; Lavretsky, Helen; Carroll, Judith E; Motivala, Sarosh J; Bootzin, Richard; Nicassio, Perry

    2014-09-01

    To investigate the comparative efficacy of cognitive behavioral therapy (CBT), Tai Chi Chih (TCC), and sleep seminar education control (SS) on the primary outcome of insomnia diagnosis, and secondary outcomes of sleep quality, fatigue, depressive symptoms, and inflammation in older adults with insomnia. Randomized controlled, comparative efficacy trial. Los Angeles community. 123 older adults with chronic and primary insomnia. Random assignment to CBT, TCC, or SS for 2-hour group sessions weekly over 4 months with follow-up at 7 and 16 months. Insomnia diagnosis, patient-reported outcomes, polysomnography (PSG), and high-sensitivity C-reactive protein (CRP) levels. CBT performed better than TCC and SS in remission of clinical insomnia as ascertained by a clinician (P < 0.01), and also showed greater and more sustained improvement in sleep quality, sleep parameters, fatigue, and depressive symptoms than TCC and SS (all P values < 0.01). As compared to SS, CBT was associated with a reduced risk of high CRP levels (> 3.0 mg/L) at 16 months (odds ratio [OR], 0.26 [95% CI, 0.07-0.97] P < 0.05). Remission of insomnia was associated with lower levels of CRP (P < 0.05) at 16 months. TCC was associated with improvements in sleep quality, fatigue, and depressive symptoms as compared to SS (all P's < 0.05), but not insomnia remission. PSG measures did not change. Treatment of late-life insomnia is better achieved and sustained by cognitive behavioral therapies. Insomnia treatment and remission reduces a marker of inflammatory risk, which has implications for cardiovascular morbidity and diabetes observed with sleep disturbance in epidemiologic surveys. © 2014 Associated Professional Sleep Societies, LLC.

  1. Controlling the Emotional Bias: Performance, Late Positive Potentials, and the Effect of Anodal Transcranial Direct Current Stimulation (tDCS).

    PubMed

    Faehling, Florian; Plewnia, Christian

    2016-01-01

    Cognitive control of emotional processing is essential for adaptive human behavior. Biased attention toward emotionally salient information is critically linked with affective disorders and is discussed as a promising treatment target. Anodal (activity enhancing) transcranial direct current stimulation (tDCS) has been shown to increase healthy and impaired cognitive control over emotional distraction and is therefore widely used for the investigation and experimental treatment of this disorder. In this study, event-related potential (ERP) were recorded parallel to tDCS to track its online effects. Healthy volunteers (n = 87) performed a delayed working memory paradigm with emotional salient and neutral distractors during stimulation with different intensities (sham, 0.5, 1, 1.5 mA). Measuring the late positive potential (LPP), an ERP that indexes attention allocation, we found that a valence-specific increase of the early portion of the LPP (eLPP, 250-500 ms) was associated with less emotional distraction in the sham group. Of note, stimulation with tDCS exerted an intensity related effect on this correlation. The later part of the LPP (lLPP, 500-1000 ms) was found to be correlated with reaction time, regardless of valence. General effect of tDCS on LPPs and task performance were not observed. These findings demonstrate that ERP recordings parallel to tDCS are feasible to investigate the neuronal underpinnings of stimulation effects on executive functions. Furthermore, they support the notion that the LPP induced by a distractive stimulus during a working memory task mirrors the additional allocation of neuronal resources with a specific sensitivity of the early LPP for highly arousing negative stimuli. Finally, together with the variable magnitude and direction of the emotional bias, the lack of systematic modulations of LPPs and behavior by tDCS further underlines the important influence of the individual brain activity patterns on stimulation effects both on the

  2. Beyond the Canon: Within-Plant and Population-Level Heterogeneity in Jasmonate Signaling Engaged by Plant-Insect Interactions

    PubMed Central

    Li, Dapeng; Baldwin, Ian T.; Gaquerel, Emmanuel

    2016-01-01

    Plants have evolved sophisticated communication and defense systems with which they interact with insects. Jasmonates are synthesized from the oxylipin pathway and act as pivotal cellular orchestrators of many of the metabolic and physiological processes that mediate these interactions. Many of these jasmonate-dependent responses are tissue-specific and translate from modulations of the canonical jasmonate signaling pathway. Here we provide a short overview of within-plant heterogeneities in jasmonate signaling and dependent responses in the context of plant-insect interactions as illuminated by examples from recent work with the ecological model, Nicotiana attenuata. We then discuss means of manipulating jasmonate signaling by creating tissue-specific jasmonate sinks, and the micrografting of different transgenic plants. The metabolic phenotyping of these manipulations provides an integrative understanding of the functional significance of deviations from the canonical model of this hormonal pathway. Additionally, natural variation in jasmonate biosynthesis and signaling both among and within species can explain polymorphisms in resistance to insects in nature. In this respect, insect-guided explorations of population-level variations in jasmonate metabolism have revealed more complexity than previously realized and we discuss how different “omic” techniques can be used to exploit the natural variation that occurs in this important signaling pathway. PMID:27135234

  3. Role of Jasmonates in the Elicitor- and Wound-Inducible Expression of Defense Genes in Parsley and Transgenic Tobacco.

    PubMed Central

    Ellard-Ivey, M.; Douglas, C. J.

    1996-01-01

    Jasmonates have been proposed to be signaling intermediates in the wound and/or elicitor-activated expression of plant defense genes. We used parsley (Petroselinum crispum) cell cultures and transgenic tobacco (Nicotiana tabacum) plants expressing 4CL1-GUS gene fusions to investigate the potential role played by jasmonates in mediating the wound and/or elicitor activation of phenylpropanoid and other defense-related genes. Jasmonates and [alpha]-linolenic acid strongly induced the expression of 4CL in a dose-dependent manner in parsley cells; methyl jasmonate also activated the coordinate expression of other phenylpropanoid genes and the accumulation of furanocoumarin phytoalexins. However, the response of the cells to optimal methyl jasmonate concentrations was distinct quantitatively and qualitatively from the response of elicitor-treated cells. In transgenic tobacco wound-inducible tobacco 4CL genes and a 4CL1 promoter-GUS transgene were responsive to jasmonates and [alpha]-linolenic acid in a dose-dependent manner. Pre-treatment of parsley cells or tobacco leaves with a lipoxygenase inhibitor reduced their responsiveness to the elicitor and to wounding. These results show that the elicitor response in parsley cells can be partially mimicked by jasmonate treatment, which supports a role for jasmonates in mediating wound-induced expression of 4CL and other phenylpropanoid genes. PMID:12226384

  4. Polymorphism in jasmonate signaling partially accounts for the variety of volatiles produced by Nicotiana attenuata plants in a native population.

    PubMed

    Schuman, Meredith C; Heinzel, Nicolas; Gaquerel, Emmanuel; Svatos, Ales; Baldwin, Ian T

    2009-01-01

    Herbivore- and jasmonate-induced volatile organic compounds (VOCs), which mediate indirect defense, must provide reliable information for predators that frequently learn to associate their release with feeding herbivores. Yet little is known about variation of these cues within populations of native plants, on a scale encountered by predators. We examined variation in herbivore-elicited VOC emissions and patterns of herbivore-induced jasmonate signaling from accessions of Nicotiana attenuata co-occurring in a native population. VOC emissions elicited by herbivore oral secretions (OS) and by methyl jasmonate (MJ) were characterized using gas chromatography-mass spectrometry (GC-MS), high-resolution two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-ToF-MS) and micro-hydrolysis and micro-hydrogenation reactions. Accessions varied in emissions of abundant (trans-alpha-bergamotene, alpha-duprezianene, trans-beta-ocimene, and cis-3-hexenol) and total detectable VOCs, as well as the accumulation of jasmonates, the jasmonate antagonist salicylic acid (SA), abscisic acid (ABA) and jasmonate signaling-related transcripts after OS elicitation. Yet MJ treatment exacerbated differences in VOC emission, suggesting that much variation in VOC emission is caused by processes downstream of jasmonate signaling. Co-occurring N. attenuata plants emit different VOCs following simulated herbivore elicitation as a result in part of differences in jasmonate production and responsiveness, which could reduce the effectiveness of induced indirect defense.

  5. Short- and long-term changes in sugarbeet (Beta vulgaris L.) gene expression after postharvest jasmonic acid treatment

    USDA-ARS?s Scientific Manuscript database

    Jasmonic acid is a natural plant hormone that induces native defense responses in plants. Sugarbeet (Beta vulgaris L.) root unigenes that were differentially expressed 2 and 60 days after a postharvest jasmonic acid treatment are presented. Data include changes in unigene expression relative to wate...

  6. Jasmonates: biosynthesis, perception, signal transduction and action in plant stress response, growth and development. An update to the 2007 review in Annals of Botany.

    PubMed

    Wasternack, C; Hause, B

    2013-06-01

    Jasmonates are important regulators in plant responses to biotic and abiotic stresses as well as in development. Synthesized from lipid-constituents, the initially formed jasmonic acid is converted to different metabolites including the conjugate with isoleucine. Important new components of jasmonate signalling including its receptor were identified, providing deeper insight into the role of jasmonate signalling pathways in stress responses and development. The present review is an update of the review on jasmonates published in this journal in 2007. New data of the last five years are described with emphasis on metabolites of jasmonates, on jasmonate perception and signalling, on cross-talk to other plant hormones and on jasmonate signalling in response to herbivores and pathogens, in symbiotic interactions, in flower development, in root growth and in light perception. The last few years have seen breakthroughs in the identification of JASMONATE ZIM DOMAIN (JAZ) proteins and their interactors such as transcription factors and co-repressors, and the crystallization of the jasmonate receptor as well as of the enzyme conjugating jasmonate to amino acids. Now, the complex nature of networks of jasmonate signalling in stress responses and development including hormone cross-talk can be addressed.

  7. Jasmonates: biosynthesis, perception, signal transduction and action in plant stress response, growth and development. An update to the 2007 review in Annals of Botany

    PubMed Central

    Wasternack, C.; Hause, B.

    2013-01-01

    Background Jasmonates are important regulators in plant responses to biotic and abiotic stresses as well as in development. Synthesized from lipid-constituents, the initially formed jasmonic acid is converted to different metabolites including the conjugate with isoleucine. Important new components of jasmonate signalling including its receptor were identified, providing deeper insight into the role of jasmonate signalling pathways in stress responses and development. Scope The present review is an update of the review on jasmonates published in this journal in 2007. New data of the last five years are described with emphasis on metabolites of jasmonates, on jasmonate perception and signalling, on cross-talk to other plant hormones and on jasmonate signalling in response to herbivores and pathogens, in symbiotic interactions, in flower development, in root growth and in light perception. Conclusions The last few years have seen breakthroughs in the identification of JASMONATE ZIM DOMAIN (JAZ) proteins and their interactors such as transcription factors and co-repressors, and the crystallization of the jasmonate receptor as well as of the enzyme conjugating jasmonate to amino acids. Now, the complex nature of networks of jasmonate signalling in stress responses and development including hormone cross-talk can be addressed. PMID:23558912

  8. Activation of the Jasmonic Acid Plant Defence Pathway Alters the Composition of Rhizosphere Bacterial Communities

    PubMed Central

    Carvalhais, Lilia C.; Dennis, Paul G.; Badri, Dayakar V.; Tyson, Gene W.; Vivanco, Jorge M.; Schenk, Peer M.

    2013-01-01

    Jasmonic acid (JA) signalling plays a central role in plant defences against necrotrophic pathogens and herbivorous insects, which afflict both roots and shoots. This pathway is also activated following the interaction with beneficial microbes that may lead to induced systemic resistance. Activation of the JA signalling pathway via application of methyl jasmonate (MeJA) alters the composition of carbon containing compounds released by roots, which are implicated as key determinants of rhizosphere microbial community structure. In this study, we investigated the influence of the JA defence signalling pathway activation in Arabidopsis thaliana on the structure of associated rhizosphere bacterial communities using 16S rRNA gene amplicon pyrosequencing. Application of MeJA did not directly influence bulk soil microbial communities but significant changes in rhizosphere community composition were observed upon activation of the jasmonate signalling pathway. Our results suggest that JA signalling may mediate plant-bacteria interactions in the soil upon necrotrophic pathogen and herbivorous insect attacks. PMID:23424661

  9. Cloning and characterization of squalene synthase gene from Poria cocos and its up-regulation by methyl jasmonate.

    PubMed

    Wang, Jian-Rong; Lin, Jun-Fang; Guo, Li-Qiong; You, Lin-Feng; Zeng, Xian-Lu; Wen, Jia-Ming

    2014-02-01

    Squalene synthase (SQS) catalyzes the condensation of two molecules of farnesyl diphosphate to give presqualene diphosphate and the subsequent rearrangement to form squalene. The gene encoding squalene synthase was cloned from Poria cocos by degenerate PCR and inverse PCR. The open reading frame of the gene is 1,497 bp, which encodes 499 amino acid residues. A phylogenetic analysis revealed that P. cocos SQS belonged to the fungus group, and was more closely related to the SQS of Ganoderma lucidum than other fungi. The treatment of P. cocos with methyl jasmonate (MeJA) significantly enhanced the transcriptional level of P. cocos sqs gene and the content of squalene in P. cocos. The transcriptional level of sqs gene was approximately fourfold higher than the control sample and the squalene content reached 128.62 μg/g, when the concentration of MeJA was 300 μM after 72 h induction.

  10. Interaction of plant cell signaling molecules, salicylic acid and jasmonic acid, with the mitochondria of Helicoverpa armigera.

    PubMed

    Akbar, S M D; Sharma, H C; Jayalakshmi, S K; Sreeramulu, K

    2012-02-01

    The cotton bollworm, Helicoverpa armigera is a polyphagous pest in Asia, Africa, and the Mediterranean Europe. Salicylic acid (SA) and jasmonic acid (JA) are the cell signaling molecules produced in response to insect attack in plants. The effect of these signaling molecules was investigated on the oxidative phosphorylation and oxidative stress of H. armigera. SA significantly inhibited the state III and state IV respiration, respiratory control index (RCI), respiratory complexes I and II, induced mitochondrial swelling, and cytochrome c release in vitro. Under in vivo conditions, SA induced state IV respiration as well as oxidative stress in time- and dose-dependent manner, and also inhibited the larval growth. In contrast, JA did not affect the mitochondrial respiration and oxidative stress. SA affected the growth and development of H. armigera, in addition to its function as signaling molecules involved in both local defense reactions at feeding sites and the induction of systemic acquired resistance in plants.

  11. Arabidopsis systemic immunity uses conserved defense signaling pathways and is mediated by jasmonates

    PubMed Central

    Truman, William; Bennett, Mark H.; Kubigsteltig, Ines; Turnbull, Colin; Grant, Murray

    2007-01-01

    In the absence of adaptive immunity displayed by animals, plants respond locally to biotic challenge via inducible basal defense networks activated through recognition and response to conserved pathogen-associated molecular patterns. In addition, immunity can be induced in tissues remote from infection sites by systemic acquired resistance (SAR), initiated after gene-for-gene recognition between plant resistance proteins and microbial effectors. The nature of the mobile signal and remotely activated networks responsible for establishing SAR remain unclear. Salicylic acid (SA) participates in the local and systemic response, but SAR does not require long-distance translocation of SA. Here, we show that, despite the absence of pathogen-associated molecular pattern contact, systemically responding leaves rapidly activate a SAR transcriptional signature with strong similarity to local basal defense. We present several lines of evidence that suggest jasmonates are central to systemic defense, possibly acting as the initiating signal for classic SAR. Jasmonic acid (JA), but not SA, rapidly accumulates in phloem exudates of leaves challenged with an avirulent strain of Pseudomonas syringae. In systemically responding leaves, transcripts associated with jasmonate biosynthesis are up-regulated within 4 h, and JA increases transiently. SAR can be mimicked by foliar JA application and is abrogated in mutants impaired in jasmonate synthesis or response. We conclude that jasmonate signaling appears to mediate long-distance information transmission. Moreover, the systemic transcriptional response shares extraordinary overlap with local herbivory and wounding responses, indicating that jasmonates may be pivotal to an evolutionarily conserved signaling network that decodes multiple abiotic and biotic stress signals. PMID:17215350

  12. Mechanisms Controlling the Effects of Bevacizumab (Avastin) on the Inhibition of Early but Not Late Formed Corneal Neovascularization

    PubMed Central

    Chu, Hsiao-Sang; Lin, Chung-Tien; Chow, Lu-Ping; Chen, Chih-Ta; Hu, Fung-Rong

    2014-01-01

    Purpose To evaluate the effects and underlying mechanisms of early and late subconjunctival injection of bevacizumab on the inhibition of corneal neovascularization (NV). Methods Corneal NV was induced by closed eye contact lens wear followed by a silk suture tarsorrhaphy in rabbits. Weekly subconjunctival injections of bevacizumab (5.0 mg) for 1 month were started immediately (early treatment group) or 1 month after induction of corneal NV with continuous induction (late treatment group). The severity of corneal NV was evaluated. Immunostaining was used to evaluate the intracorneal diffusion of bevacizumab, and the existence of pericytes and smooth muscle cells around the NV. The expression of AM-3K, an anti-macrophage antibody, vascular endothelial growth factor (VEGF) with its receptors (VEGFR1 and VEGFR2), and vascular endothelial apoptosis were also evaluated. Western blot analysis was performed to quantify the expression level of VEGF, VEGFR1 and VEGFR2 on corneal epithelium and stroma in different groups. Results Early treatment with bevacizumab inhibited corneal NV more significantly than late treatment. Intracorneal diffusion of bevacizumab was not different among different groups. Immunostaining showed pericytes and smooth muscle cells around newly formed vessels as early as 2 weeks after induction. Immunostaining and Western blot analysis showed that VEGF, VEGFR1, and VEGFR2 on corneal stroma increased significantly in no treatment groups and late treatment groups, but not in early treatment group. Bevacizumab significantly inhibited macrophage infiltration in the early but not late treatment group. Sporadic vascular endothelial apoptosis was found at 4 weeks in the late but not early treatment group. Conclusions Early but not late injection of bevacizumab inhibited corneal NV. Late injection of bevacizumab did not alter macrophage infiltration, and can't inhibit the expression of VEGF, VEGFR1, and VEGFR2 on corneal vessels. The inhibition of corneal NV

  13. Stimulation of betacyanin synthesis through exogenous methyl jasmonate and other elicitors in suspension-cultured cells of Portulaca.

    PubMed

    Bhuiyan, Nazmul H; Adachi, Taiji

    2003-09-01

    Betacyanin production in suspension-cultured cells of Portulaca was significantly enhanced by both abiotic and biotic elicitors. Betacyanin levels increased 1.3 and 1.5-fold over the controls in the presence of two abiotic elicitors (20 mumol/L CuSO4 and 100 mumol/L FeEDTA) and increased 1.8 and 1.6-fold in the presence of two biotic elicitors (0.5 mg/L beta-glucan and 0.5 mg/L chitosan). Maximum betacyanin synthesis with the two most effective elicitors was obtained when cultures were treated on day 1 and day 0 by beta-glucan and FeEDTA, respectively. A concentration-dependent response was exhibited by cultures treated with exogenous methyl jasmonate (MJ). MJ alone at 0.1 mumol/L caused a 2.6-fold increase in betacyanin synthesis when administered to the suspension culture on day 3. However, no additive effect on betacyanin accumulation was observed in treatments, which combined MJ and beta-glucan or FeEDTA. Treatment with ibuprofen (IB), an inhibitor of jasmonate biosynthesis, reduced the level of betacyanin in cells cultured in standard medium at all concentrations tested (25, 50, 100 mumol/L). The effect of IB on betacyanin synthesis in the cells treated with MJ or beta-glucan, however, differed with the IB concentration applied. The two higher concentrations (50 and 100 mumol/L) of IB significantly reduced the betacyanin content while the lower concentration (25 mumol/L) did not show an adverse effect on the betacyanin enhancement triggered by MJ or beta-glucan. Our findings suggest that, in suspension-cultured cells of Portulaca, an MJ-mediated signal transduction pathway prominently exists in betacyanin synthesis. This pathway seems to act antagonistically towards beta-glucan-mediated signaling. As far as we know this is the first report on the elevation of betacyanin level by jasmonate or other elicitors in cell suspension cultures.

  14. Going to sleep in the supine position is a modifiable risk factor for late pregnancy stillbirth; Findings from the New Zealand multicentre stillbirth case-control study.

    PubMed

    McCowan, Lesley M E; Thompson, John M D; Cronin, Robin S; Li, Minglan; Stacey, Tomasina; Stone, Peter R; Lawton, Beverley A; Ekeroma, Alec J; Mitchell, Edwin A

    2017-01-01

    Our objective was to test the primary hypothesis that maternal non-left, in particular supine going-to-sleep position, would be a risk factor for late stillbirth (≥28 weeks of gestation). A multicentre case-control study was conducted in seven New Zealand health regions, between February 2012 and December 2015. Cases (n = 164) were women with singleton pregnancies and late stillbirth, without congenital abnormality. Controls (n = 569) were women with on-going singleton pregnancies, randomly selected and frequency matched for health region and gestation. The primary outcome was adjusted odds of late stillbirth associated with self-reported going-to-sleep position, on the last night. The last night was the night before the late stillbirth was thought to have occurred or the night before interview for controls. Going-to-sleep position on the last night was categorised as: supine, left-side, right-side, propped or restless. Multivariable logistic regression adjusted for known confounders. Supine going-to-sleep position on the last night was associated with increased late stillbirth risk (adjusted odds ratios (aOR) 3.67, 95% confidence interval (CI) 1.74 to 7.78) with a population attributable risk of 9.4%. Other independent risk factors for late stillbirth (aOR, 95% CI) were: BMI (1.04, 1.01 to 1.08) per unit, maternal age ≥40 (2.88, 1.31 to 6.32), birthweight <10th customised centile (2.76, 1.59 to 4.80), and <6 hours sleep on the last night (1.81, 1.14 to 2.88). The risk associated with supine-going-to-sleep position was greater for term (aOR 10.26, 3.00 to 35.04) than preterm stillbirths (aOR 3.12, 0.97 to 10.05). Supine going-to-sleep position is associated with a 3.7 fold increase in overall late stillbirth risk, independent of other common risk factors. A public health campaign encouraging women not to go-to-sleep supine in the third trimester has potential to reduce late stillbirth by approximately 9%.

  15. Early to Late Endosome Trafficking Controls Secretion and Zymogen Activation in Rodent and Human Pancreatic Acinar Cells.

    PubMed

    Messenger, Scott W; Thomas, Diana Dh; Cooley, Michelle M; Jones, Elaina K; Falkowski, Michelle A; August, Benjamin K; Fernandez, Luis A; Gorelick, Fred S; Groblewski, Guy E

    2015-11-01

    Pancreatic acinar cells have an expanded apical endosomal system, the physiological and pathophysiological significance of which is still emerging. Phosphatidylinositol-3,5-bisphosphate (PI(3,5)P2) is an essential phospholipid generated by PIKfyve, which phosphorylates phosphatidylinositol-3-phosphate (PI(3)P). PI(3,5)P2 is necessary for maturation of early endosomes (EE) to late endosomes (LE). Inhibition of EE to LE trafficking enhances anterograde endosomal trafficking and secretion at the plasma membrane by default through a recycling endosome (RE) intermediate. We assessed the effects of modulating PIKfyve activity on apical trafficking and pancreatitis responses in pancreatic acinar cells. Inhibition of EE to LE trafficking was achieved using pharmacological inhibitors of PIKfyve, expression of dominant negative PIKfyve K1877E, or constitutively active Rab5-GTP Q79L. Anterograde endosomal trafficking was manipulated by expression of constitutively active and dominant negative Rab11a mutants. The effects of these agents on secretion, endolysosomal exocytosis of lysosome associated membrane protein (LAMP1), and trypsinogen activation in response to high-dose CCK-8, bile acids and cigarette toxin was determined. PIKfyve inhibition increased basal and stimulated secretion. Adenoviral overexpression of PIKfyve decreased secretion leading to cellular death. Expression of Rab5-GTP Q79L or Rab11a-GTP Q70L enhanced secretion. Conversely, dominant-negative Rab11a-GDP S25N reduced secretion. High-dose CCK inhibited endolysosomal exocytosis that was reversed by PIKfyve inhibition. PIKfyve inhibition blocked intracellular trypsin accumulation and cellular damage responses to high CCK-8, tobacco toxin, and bile salts in both rodent and human acini. These data demonstrate that EE-LE trafficking acutely controls acinar secretion and the intracellular activation of zymogens leading to the pathogenicity of acute pancreatitis.

  16. Severe Psychiatric Disorders in Mid-Life and Risk of Dementia in Late-Life (Age 65-84 Years): A Population Based Case-Control Study

    PubMed Central

    Zilkens, Renate R.; Bruce, David G.; Duke, Janine; Spilsbury, Katrina; Semmens, James B.

    2014-01-01

    Objective: To examine the association of mid-life exposure to several psychiatric disorders with the development of late-life dementia. Methods: A matched case-control study using Western Australian state-wide hospital inpatient, outpatient mental health and emergency records linked to death records. Incident dementia cases (2000-2009) aged 65 to 84 years were sex- and age-matched to an electoral roll control. Records as far back as 1970 were used to assess exposure to medical risk factors before age 65 years. Candidate psychiatric risk factors were required to be present at least 10 years before dementia onset to ensure direction of potential causality. Odds ratios were estimated using conditional logistic regression. Results: 13, 568 dementia cases (median age 78.7 years, 43.4% male) were matched to a control. Depression, bipolar disorder, schizophrenia, anxiety disorder and alcohol dependence were found to be significant and independent risk factors for late-life dementia after adjusting for diabetes, heart disease, cerebrovascular disease and smoking risk factors. The effect of a history of depression, schizophrenia and alcohol dependency on dementia risk varied with age, being strongest for earlier onset late-life dementia and waning at older ages. Conclusion: Severe depression, anxiety disorder, bipolar disorder, schizophrenia and alcoholic dependency disorder treated by specialists in psychiatric facilities in mid-life are important risk factors for late-life dementia. These psychiatric conditions need to be considered in future studies of the risk and prevention of late-life dementia. PMID:25115541

  17. Sea-level and tectonic control of middle to late Pleistocene turbidite systems in Santa Monica Basin, offshore California

    USGS Publications Warehouse

    Normark, W.R.; Piper, D.J.W.; Sliter, R.

    2006-01-01

    Small turbidite systems offshore from southern California provide an opportunity to track sediment from river source through the turbidity-current initiation process to ultimate deposition, and to evaluate the impact of changing sea level and tectonics. The Santa Monica Basin is almost a closed system for terrigenous sediment input, and is supplied principally from the Santa Clara River. The Hueneme fan is supplied directly by the river, whereas the smaller Mugu and Dume fans are nourished by southward longshore drift. This study of the Late Quaternary turbidite fill of the Santa Monica Basin uses a dense grid of high-resolution seismic-reflection profiles tied to new radiocarbon ages for Ocean Drilling Program (ODP) Site 1015 back to 32 ka. Over the last glacial cycle, sedimentation rates in the distal part of Santa Monica Basin averaged 2-3 mm yr-1, with increases at times of extreme relative sea-level lowstand. Coarser-grained mid-fan lobes prograded into the basin from the Hueneme, Mugu and Dume fans at times of rapid sea-level fall. These pulses of coarse-grained sediment resulted from river channel incision and delta cannibalization. During the extreme lowstand of the last glacial maximum, sediment delivery was concentrated on the Hueneme Fan, with mean depositional rates of up to 13 mm yr-1 on the mid- and upper fan. During the marine isotope stage (MIS) 2 transgression, enhanced rates of sedimentation of > 4 mm yr-1 occurred on the Mugu and Dume fans, as a result of distributary switching and southward littoral drift providing nourishment to these fan systems. Longer-term sediment delivery to Santa Monica Basin was controlled by tectonics. Prior to MIS 10, the Anacapa ridge blocked the southward discharge of the Santa Clara River into the Santa Monica Basin. The pattern and distribution of turbidite sedimentation was strongly controlled by sea level through the rate of supply of coarse sediment and the style of initiation of turbidity currents. These two

  18. Arabidopsis WRKY57 functions as a node of convergence for jasmonic acid- and auxin-mediated signaling in jasmonic acid-induced leaf senescence.

    PubMed

    Jiang, Yanjuan; Liang, Gang; Yang, Shizhuo; Yu, Diqiu

    2014-01-01

    Leaf senescence is regulated by diverse developmental and environmental factors. Exogenous jasmonic acid (JA) can induce leaf senescence, whereas auxin suppresses this physiological process. Crosstalk between JA and auxin signaling has been well studied, but not during JA-induced leaf senescence. Here, we found that upon methyl jasmonate treatment, Arabidopsis thaliana wrky57 mutants produced typical leaf senescence symptoms, such as yellowing leaves, low chlorophyll content, and high cell death rates. Further investigation suggested that senescence-associated genes were upregulated in the wrky57 mutants. Chromatin immunoprecipitation experiments revealed that WRKY57 directly binds to the promoters of SENESCENCE4 and SENESCENCE-ASSOCIATED GENE12 and represses their transcription. In vivo and in vitro experiments suggested that WRKY57 interacts with JASMONATE ZIM-DOMAIN4/8 (JAZ4/8) and the AUX/IAA protein IAA29, repressors of the JA and auxin signaling pathways, respectively. Consistent with the opposing functions of JA and auxin in JA-induced leaf senescence, JAZ4/8 and IAA29 also displayed opposite functions in JA-induced leaf senescence and competitively interacted with WRKY57. Our results suggested that the JA-induced leaf senescence process can be antagonized by auxin via WRKY57. Moreover, WRKY57 protein levels were downregulated by JA but upregulated by auxin. Therefore, as a repressor in JA-induced leaf senescence, WRKY57 is a common component of the JA- and auxin-mediated signaling pathways.

  19. Rice allelopathy induced by methyl jasmonate and methyl salicylate.

    PubMed

    Bi, Hai Hong; Zeng, Ren Sen; Su, Li Ming; An, Min; Luo, Shi Ming

    2007-05-01

    Methyl jasmonate (MeJA) and methyl salicylate (MeSA) are important signaling molecules that induce plant defense against insect herbivores and microbial pathogens. We tested the hypothesis that allelopathy is an inducible defense mechanism, and that the JA and SA signaling pathways may activate allelochemicals release. Exogenous application of MeJA and MeSA to rice (Oryza sativa L.) enhanced rice allelopathic potential and led to accumulation of phenolics, an increase in enzymatic activities, and gene transcription of phenylalanine ammonia-lyase (PAL) and cinnamate 4-hydroxylase (C4H), two key enzymes in the phenylpropanoid pathway. Aqueous extracts of the leaves of rice IAC165, a putative allelopathic variety, treated with MeSA (5 mM) or MeJA (0.05 mM), showed increased inhibitory effects (25 and 21%, respectively) on root growth of barnyardgrass (Echinochloa crus-galli L.), and increased inhibitory effects (18 and 23%, respectively) on shoot growth. Aqueous extracts from leaves of Huajingxian 1 rice, a putative nonallelopathic variety treated with MeJA and MeSA, caused 63 and 24% inhibition of root growth in barnyardgrass seedlings. The root exudates of both IAC165 and Huajingxian 1 plants treated with MeJA and MeSA for 48 hr also showed significant increases in their inhibitory effects on root growth of barnyardgrass seedlings. At the four-leaf stage, levels of 3,4-hydroxybenzoic acid, vanillic acid, coumaric acid, and ferulic acid that accumulated in the leaves were 5.3-, 31.3-, 2.2-, and 1.7-fold higher in response to MeJA exposure, and 3.3-, 13.1-, 2.0-, and 2.2-fold higher in response to MeSA. Treatments of MeSA and MeJA enhanced the PAL activity in the rice leaves up to 52.3 and 80.1%, respectively, whereas C4H activity was increased by 40.2 and 67%. Gene transcription of PAL and C4H in rice leaves significantly increased after the plants were subjected to treatment with MeJA and MeSA. These results suggest that allelopathy may be an active defense

  20. Aphid antixenosis in cotton is activated by the natural plant defence elicitor cis-jasmone.

    PubMed

    Hegde, Mahabaleshwar; Oliveira, Janser N; da Costa, Joao G; Loza-Reyes, Elisa; Bleicher, Ervino; Santana, Antonio E G; Caulfield, John C; Mayon, Patrick; Dewhirst, Sarah Y; Bruce, Toby J A; Pickett, John A; Birkett, Michael A

    2012-06-01

    Upon insect herbivory, plants can release blends of volatile organic compounds (VOCs) that modify herbivore and natural enemy behaviour. We have shown recently that cotton, Gossypium hirsutum, emits a blend of defence VOCs that repels the cotton aphid, Aphis gossypii, upon herbivory by this notorious crop pest, including (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT). In this study, we investigated changes in the defence VOC profile of G. hirsutum induced by the naturally-occurring plant elicitor cis-jasmone (CJ) and whether these changes modify the behaviour of A. gossypii. In four-arm olfactometer assays, VOCs from untreated plants were significantly attractive (P<0.05), whilst VOCs from CJ-treated plants were significantly repellent (P<0.05). The VOCs induced by CJ appeared to comprise (Z)-3-hexenyl acetate, DMNT, methyl salicylate and TMTT. In quantitative VOC collection studies, sustained release of DMNT and TMTT was observed in CJ-treated plants over a period of five days, with levels becoming statistically significantly higher than for control treated plants on the fifth day in most cases. Despite earlier indications, no statistically significant differences were observed in levels of (Z)-3-hexenyl acetate or methyl salicylate between CJ and control treatments on any day. Furthermore, DMNT and TMTT emissions from CJ-treated plants were further enhanced by subsequent addition of A. gossypii. CJ treatment induced statistically significantly higher DMNT and TMTT expression levels as early as day three, when A. gossypii was present. The results in this study show that CJ can induce the production of A. gossypii-induced VOCs from G. hirsutum, with potential for deployment in novel crop protection strategies. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Methyl jasmonate, gibberellic acid, and auxin affect transcription and transcript accumulation of chloroplast genes in barley.

    PubMed

    Zubo, Yan O; Yamburenko, Maria V; Kusnetsov, Viktor V; Börner, Thomas

    2011-08-15

    Phytohormones control growth and development of plants. Their effects on the expression of nuclear genes are well investigated. Although they influence plastid-related processes, it is largely unknown whether phytohormones exert their control also by regulating the expression of plastid/chloroplast genes. We have therefore studied the effects of methyl jasmonate (MeJA), gibberellic acid (GA(3)), an auxin (indole-3-acetic acid, IAA), a brassinosteroid (24-epibrassinolide, BR) and a cytokinin (6-benzyladenine) on transcription (run-on assays) and transcript levels (RNA blot hybridization) of chloroplast genes after incubation of detached barley leaves in hormone solutions. BR was the only hormone without significant influence on chloroplast transcription. It showed, however, a weak reducing effect on transcript accumulation. MeJA, IAA and GA(3) repressed both transcription and transcript accumulation, while BA counteracted the effects of the other hormones. Effects of phytohormones on transcription differed in several cases from their influence on transcript levels suggesting that hormones may act via separate signaling pathways on transcription and transcript accumulation in chloroplasts. We observed striking differences in the response of chloroplast gene expression on phytohormones between the lower (young cells) and the upper segments (oldest cells) of barley leaves. Quantity and quality of the hormone effects on chloroplast gene expression seem to depend therefore on the age and/or developmental stage of the cells. As the individual chloroplast genes responded in different ways on phytohormone treatment, gene- and transcript-specific factors should be involved. Our data suggest that phytohormones adjust gene expression in the nucleo-cytoplasmic compartment and in plastids/chloroplasts in response to internal and external cues. Copyright © 2011 Elsevier GmbH. All rights reserved.

  2. New insights into the early biochemical activation of jasmonic acid biosynthesis in leaves

    PubMed Central

    Baldwin, Ian T

    2010-01-01

    In plants, herbivore attack elicits the rapid accumulation of jasmonic acid (JA) which results from the activation of constitutively expressed biosynthetic enzymes. The molecular mechanisms controlling the activation of JA biosynthesis remain largely unknown however new research has elucidated some of the early regulatory components involved in this process. Nicotiana attenuata plants, a wild tobacco species, responds to fatty acid amino acid conjuguates (FAC) elicitors in the oral secretion of its natural herbivore, Manduca sexta, by triggering specific defense and tolerance responses against it; all of the defense responses known to date require the amplification of the wound-induced JA increase. We recently demonstrated that this FAC-elicited JA burst requires an increased flux of free linolenic acid (18:3) likely originating from the activation of a plastidial glycerolipase (GLA1) which is activated by an abundant FAC found in insect oral secretions, N-linolenoyl-glutamate (18:3-Glu). The lack of accumulation of free 18:3 after elicitation suggests a tight physical association between GLA1 and LOX3 in N. attenuata leaves. In addition, the salicylate-induced protein kinase (SIPK) and the nonexpressor of PR-1 (NPR1) participate in this activation mechanism that controls the supply of 18:3. In contrast, the wound-induced protein kinase (WIPK) does not but instead regulates the conversion of 13(S)-hydroperoxy-18:3 into 12-oxo-phytodienoic acid (OPDA). These results open new perspectives on the complex network of signals and regulatory components inducing the JA biosynthetic pathway. PMID:20037473

  3. Metabolomics Analysis and Biosynthesis of Rosmarinic Acid in Agastache rugosa Kuntze Treated with Methyl Jasmonate

    PubMed Central

    Uddin, Md. Romij; Xu, Hui; Park, Woo Tae; Tuan, Pham Anh; Li, Xiaohua; Chung, Eunsook; Lee, Jai-Heon; Park, Sang Un

    2013-01-01

    This study investigated the effect of methyl jasmonate (MeJA) on metabolic profiles and rosmarinic acid (RA) biosynthesis in cell cultures of Agastache rugosa Kuntze. Transcript levels of phenylpropanoid biosynthetic genes, i.e., ArPAL, Ar4CL, and ArC4H, maximally increased 4.5-fold, 3.4-fold, and 3.5-fold, respectively, compared with the untreated controls, and the culture contained relatively high amounts of RA after exposure of cells to 50 µM MeJA. RA levels were 2.1-, 4.7-, and 3.9-fold higher after exposure to 10, 50, and 100 µM MeJA, respectively, than those in untreated controls. In addition, the transcript levels of genes attained maximum levels at different time points after the initial exposure. The transcript levels of ArC4H and Ar4CL were transiently induced by MeJA, and reached a maximum of up to 8-fold at 3 hr and 6 hr, respectively. The relationships between primary metabolites and phenolic acids in cell cultures of A. rugosa treated with MeJA were analyzed by gas chromatography coupled with time-of-flight mass spectrometry. In total, 45 metabolites, including 41 primary metabolites and 4 phenolic acids, were identified from A. rugosa. Metabolite profiles were subjected to partial least square-discriminate analysis to evaluate the effects of MeJA. The results indicate that both phenolic acids and precursors for the phenylpropanoid biosynthetic pathway, such as aromatic amino acids and shikimate, were induced as a response to MeJA treatment. Therefore, MeJA appears to have an important impact on RA accumulation, and the increased RA accumulation in the treated cells might be due to activation of the phenylpropanoid genes ArPAL, ArC4H, and Ar4CL. PMID:23724034

  4. The protective effects of methyl jasmonate against adriamycin--induced hepatic and renal toxicities.

    PubMed

    Kosoko, A M; Molokwu, C J; Farombi, E O; Ademowo, O G

    2012-12-01

    The aim of the study was to investigate the protective effect of methyl jasmonate (MJ) in adriamycin (ADR) induced hepatic and renal toxicities. 36 BALB/c mice were randomly divided into control, ADR (20 mg/kg), MJ (50 mg/kg) only, MJ (100 mg/kg) only, MJ (50 mg/ kg) + ADR, MJ (100 mg/kg) + ADR groups (n = 6). The 2 doses of MJ was administered for 7 days in MJ only groups, ADR was administered intraperitoneally on the 8th day after pretreatment with the 2 different doses of MJ while ADR was administered on the 8th day only for the ADR only group. The malondialdehyde (MDA), glutathione (GSH), H2O2 generation, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea and creatinine in the liver, kidneys and serum samples as applicable were estimated. Tissue MDA, H2O2 generation, and GST activity were markedly elevated while GSH content, CAT and SOD activities were significantly reduced in the tissues when compared to the control (p < 0.05). Pretreatment with MJ ameliorated ADR toxicities, with a significant reduction in serum urea concentration, ALT activity, MDA level, H2O2 generation, GST activity and a significant elevation in GSH content, CAT and SOD activities in the organ tissues. MJ induced significant reduction in MDA level and increase of GSH content in liver and kidney tissues. This study suggests that MJ may play an overall protective effect on ADR-induced toxicities in liver and kidneys and the inhibition of tissue peroxidative damage might contribute to this beneficial effect.

  5. MYC2 Orchestrates a Hierarchical Transcriptional Cascade That Regulates Jasmonate-Mediated Plant Immunity in Tomato[OPEN

    PubMed Central

    Liu, Yuanyuan; Deng, Lei; Wu, Fangming; Huang, Zhuo; Zhou, Ming; Chen, Qian; Zhong, Silin

    2017-01-01

    The hormone jasmonate (JA), which functions in plant immunity, regulates resistance to pathogen infection and insect attack through triggering genome-wide transcriptional reprogramming in plants. We show that the basic helix-loop-helix transcription factor (TF) MYC2 in tomato (Solanum lycopersicum) acts downstream of the JA receptor to orchestrate JA-mediated activation of both the wounding and pathogen responses. Using chromatin immunoprecipitation sequencing (ChIP-seq) coupled with RNA sequencing (RNA-seq) assays, we identified 655 MYC2-targeted JA-responsive genes. These genes are highly enriched in Gene Ontology categories related to TFs and the early response to JA, indicating that MYC2 functions at a high hierarchical level to regulate JA-mediated gene transcription. We also identified a group of MYC2-targeted TFs (MTFs) that may directly regulate the JA-induced transcription of late defense genes. Our findings suggest that MYC2 and its downstream MTFs form a hierarchical transcriptional cascade during JA-mediated plant immunity that initiates and amplifies transcriptional output. As proof of concept, we showed that during plant resistance to the necrotrophic pathogen Botrytis cinerea, MYC2 and the MTF JA2-Like form a transcription module that preferentially regulates wounding-responsive genes, whereas MYC2 and the MTF ETHYLENE RESPONSE FACTOR.C3 form a transcription module that preferentially regulates pathogen-responsive genes. PMID:28733419

  6. Jasmonic acid effect on the fatty acid and terpenoid indole alkaloid accumulation in cell suspension cultures of Catharanthus roseus.

    PubMed

    Goldhaber-Pasillas, Guitele Dalia; Mustafa, Natali Rianika; Verpoorte, Robert

    2014-07-15

    The stress response after jasmonic acid (JA) treatment was studied in cell suspension cultures of Catharanthus roseus. The effect of JA on the primary and secondary metabolism was based on changes in profiles of fatty acids (FA) and terpenoid indole alkaloids (TIA). According to multivariate data analyses (MVDA), three major time events were observed and characterized according to the variations of specific FA and TIA: after 0-30 min of induction FA such as C18:1, C20:0, C22:0 and C24:0 were highly induced by JA; 90-360 min after treatment was characterized by variations of C14:0 and C15:0; and 1440 min after induction JA had the largest effect on both group of metabolites were C18:1, C18:2, C18:3, C16:0, C20:0, C22:0, C24:0, catharanthine, tabersonine-like 1, serpentine, tabersonine and ajmalicine-like had the most significant variations. These results unambiguously demonstrate the profound effect of JA particularly on the accumulation of its own precursor, C18:3 and the accumulation of TIA, which can be considered as late stress response events to JA since they occurred only after 1440 min. These observations show that the early events in the JA response do not involve the de novo biosynthesis of neither its own precursor nor TIA, but is due to an already present biochemical system.

  7. Neonatal gram-negative bacillary late-onset sepsis: A case-control-control study on a prospectively collected database of 5,233 admissions.

    PubMed

    Tsai, Ming-Horng; Wu, I Hsyuan; Lee, Chiang-Wen; Chu, Shih-Ming; Lien, Reyin; Huang, Hsuan-Rong; Chiang, Ming-Chou; Fu, Ren-Huei; Hsu, Jen-Fu; Huang, Yhu-Chering

    2016-02-01

    Gram-negative bacillary (GNB) bloodstream infections account for 20%-30% of neonatal late-onset sepsis (LOS). We aimed to identify the incidence, clinical characteristics, and risk factors for adverse outcomes in neonates with GNB LOS. All patients with GNB LOS admitted to the neonatal intensive care units (NICUs) of a university-affiliated teaching hospital in Taiwan from January 1, 2004-December 31, 2011, were enrolled. A case-control-control study was performed to evaluate risk factors for acquisition of neonatal GNB LOS. Of the 5,010 neonates, 290 (5.8%) had a total of 346 episodes of GNB LOS (36.7% of total LOS), with an incidence rate of 13.6 per 10,000 neonate hospital days. The overall mortality rate was 17.6% (51/290), and the sepsis attributable mortality rate was 9.8% (34/346 episodes). After multivariate logistic regression analysis, neonates with prolonged use of total parenteral nutrition (adjusted odds ratio [OR] = 1.53; 95% confidence interval [CI], 1.02-2.29; P = .041) were independently associated with acquisition of GNB LOS. The independent predictors of in-hospital mortality were Pseudomonas aeruginosa etiology (OR = 11.45; 95% CI, 2.83-46.24) and underlying secondary pulmonary hypertension (OR = 18.02; 95% CI, 3.28-98.89), renal disease (OR = 17.16; 95% CI, 2.96-99.38), and neuromuscular comorbidities (OR = 2.72; 95% CI, 1.06-7.00). Given the higher illness severity and sepsis-attributable mortality rate of neonatal GNB LOS in the NICU, strategies to reduce the incidence need to be addressed urgently. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  8. PgLOX6 encoding a lipoxygenase contributes to jasmonic acid biosynthesis and ginsenoside production in Panax ginseng

    PubMed Central

    Rahimi, Shadi; Kim, Yu-Jin; Sukweenadhi, Johan; Zhang, Dabing; Yang, Deok-Chun

    2016-01-01

    Ginsenosides, the valuable pharmaceutical compounds in Panax ginseng, are triterpene saponins that occur mainly in ginseng plants. It was shown that in vitro treatment with the phytohormone jasmonic acid (JA) is able to increase ginsenoside production in ginseng plants. To understand the molecular link between JA biosynthesis and ginsenoside biosynthesis, we identified a JA biosynthetic 13-lipoxygenase gene (PgLOX6) in P. ginseng that promotes ginsenoside production. The expression of PgLOX6 was high in vascular bundles, which corresponds with expression of ginsenoside biosynthetic genes. Consistent with the role of PgLOX6 in synthesizing JA and promoting ginsenoside synthesis, transgenic plants overexpressing PgLOX6 in Arabidopsis had increased amounts of JA and methyl jasmonate (MJ), increased expression of triterpene biosynthetic genes such as squalene synthase (AtSS1) and squalene epoxidase (AtSE1), and increased squalene content. Moreover, transgenic ginseng roots overexpressing PgLOX6 had around 1.4-fold increased ginsenoside content and upregulation of ginsenoside biosynthesis-related genes including PgSS1, PgSE1, and dammarenediol synthase (PgDDS), which is similar to that of treatment with MJ. However, MJ treatment of transgenic ginseng significantly enhanced JA and MJ, associated with a 2.8-fold increase of ginsenoside content compared with the non-treated, non-transgenic control plant, which was 1.4 times higher than the MJ treatment effect on non-transgenic plants. These results demonstrate that PgLOX6 is responsible for the biosynthesis of JA and promotion of the production of triterpenoid saponin through up-regulating the expression of ginsenoside biosynthetic genes. This work provides insight into the role of JA in biosynthesizing secondary metabolites and provides a molecular tool for increasing ginsenoside production. PMID:27811076

  9. The Juvenile Phase of Maize Sees Upregulation of Stress-Response Genes and Is Extended by Exogenous Jasmonic Acid.

    PubMed

    Beydler, Benjamin; Osadchuk, Krista; Cheng, Chi-Lien; Manak, J Robert; Irish, Erin E

    2016-08-01

    As maize (Zea mays) plants undergo vegetative phase change from juvenile to adult, they both exhibit heteroblasty, an abrupt change in patterns of leaf morphogenesis, and gain the ability to produce flowers. Both processes are under the control of microRNA156 (miR156), whose levels decline at the end of the juvenile phase. Gain of the ability to flower is conferred by the expression of miR156 targets that encode SQUAMOSA PROMOTER-BINDING transcription factors, which, when derepressed in the adult phase, induce the expression of MADS box transcription factors that promote maturation and flowering. How gene expression, including targets of those microRNAs, differs between the two phases remains an open question. Here, we compare transcript levels in primordia that will develop into juvenile or adult leaves to identify genes that define these two developmental states and may influence vegetative phase change. In comparisons among successive leaves at the same developmental stage, plastochron 6, three-fourths of approximately 1,100 differentially expressed genes were more highly expressed in primordia of juvenile leaves. This juvenile set was enriched in photosynthetic genes, particularly those associated with cyclic electron flow at photosystem I, and in genes involved in oxidative stress and retrograde redox signaling. Pathogen- and herbivory-responsive pathways including salicylic acid and jasmonic acid also were up-regulated in juvenile primordia; indeed, exogenous application of jasmonic acid delayed both the appearance of adult traits and the decline in the expression of miR156-encoding loci in maize seedlings. We hypothesize that the stresses associated with germination promote juvenile patterns of differentiation in maize. © 2016 American Society of Plant Biologists. All Rights Reserved.

  10. PgLOX6 encoding a lipoxygenase contributes to jasmonic acid biosynthesis and ginsenoside production in Panax ginseng.

    PubMed

    Rahimi, Shadi; Kim, Yu-Jin; Sukweenadhi, Johan; Zhang, Dabing; Yang, Deok-Chun

    2016-11-01

    Ginsenosides, the valuable pharmaceutical compounds in Panax ginseng, are triterpene saponins that occur mainly in ginseng plants. It was shown that in vitro treatment with the phytohormone jasmonic acid (JA) is able to increase ginsenoside production in ginseng plants. To understand the molecular link between JA biosynthesis and ginsenoside biosynthesis, we identified a JA biosynthetic 13-lipoxygenase gene (PgLOX6) in P. ginseng that promotes ginsenoside production. The expression of PgLOX6 was high in vascular bundles, which corresponds with expression of ginsenoside biosynthetic genes. Consistent with the role of PgLOX6 in synthesizing JA and promoting ginsenoside synthesis, transgenic plants overexpressing PgLOX6 in Arabidopsis had increased amounts of JA and methyl jasmonate (MJ), increased expression of triterpene biosynthetic genes such as squalene synthase (AtSS1) and squalene epoxidase (AtSE1), and increased squalene content. Moreover, transgenic ginseng roots overexpressing PgLOX6 had around 1.4-fold increased ginsenoside content and upregulation of ginsenoside biosynthesis-related genes including PgSS1, PgSE1, and dammarenediol synthase (PgDDS), which is similar to that of treatment with MJ. However, MJ treatment of transgenic ginseng significantly enhanced JA and MJ, associated with a 2.8-fold increase of ginsenoside content compared with the non-treated, non-transgenic control plant, which was 1.4 times higher than the MJ treatment effect on non-transgenic plants. These results demonstrate that PgLOX6 is responsible for the biosynthesis of JA and promotion of the production of triterpenoid saponin through up-regulating the expression of ginsenoside biosynthetic genes. This work provides insight into the role of JA in biosynthesizing secondary metabolites and provides a molecular tool for increasing ginsenoside production. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  11. Jasmonic acid is a downstream component in the modulation of somatic embryogenesis by Arabidopsis Class 2 phytoglobin

    PubMed Central

    Mira, Mohamed M.; Wally, Owen S. D.; Elhiti, Mohamed; El-Shanshory, Adel; Reddy, Dhadi S.; Hill, Robert D.; Stasolla, Claudio

    2016-01-01

    Previous studies have shown that the beneficial effect of suppression of the Arabidopsis phytoglobin 2 gene, PGB2, on somatic embryogenesis occurs through the accumulation of nitric oxide (NO) within the embryogenic cells originating from the cultured explant. NO activates the expression of Allene oxide synthase (AOS) and Lipoxygenase 2 (LOX2), genes encoding two key enzymes of the jasmonic acid (JA) biosynthetic pathway, elevating JA content within the embryogenic tissue. The number of embryos in the single aos1-1 mutant and pgb2-aos1-1 double mutant declined, and was not rescued by increasing levels of NO stimulating embryogenesis in wild-type tissue. NO also influenced JA responses by up-regulating PLANT DEFENSIN 1 (PDF1) and JASMONATE-ZIM-PROTEIN (JAZ1), as well as down-regulating MYC2. The NO and JA modulation of MYC2 and JAZ1 controlled embryogenesis. Ectopic expression of JAZ1 or suppression of MYC2 promoted the formation of somatic embryos, while repression of JAZ1 and up-regulation of MYC2 reduced the embryogenic performance. Sustained expression of JAZ1 induced the transcription of several indole acetic acid (IAA) biosynthetic genes, resulting in higher IAA levels in the embryogenic cells. Collectively these data fit a model integrating JA in the PGB2 regulation of Arabidopsis embryogenesis. Suppression of PGB2 increases JA through NO. Elevated levels of JA repress MYC2 and induce JAZ1, favoring the accumulation of IAA in the explants and the subsequent production of somatic embryos. PMID:26962208

  12. Jasmonic acid is a downstream component in the modulation of somatic embryogenesis by Arabidopsis Class 2 phytoglobin.

    PubMed

    Mira, Mohamed M; Wally, Owen S D; Elhiti, Mohamed; El-Shanshory, Adel; Reddy, Dhadi S; Hill, Robert D; Stasolla, Claudio

    2016-04-01

    Previous studies have shown that the beneficial effect of suppression of the Arabidopsis phytoglobin 2 gene, PGB2, on somatic embryogenesis occurs through the accumulation of nitric oxide (NO) within the embryogenic cells originating from the cultured explant. NO activates the expression of Allene oxide synthase (AOS) and Lipoxygenase 2 (LOX2), genes encoding two key enzymes of the jasmonic acid (JA) biosynthetic pathway, elevating JA content within the embryogenic tissue. The number of embryos in the single aos1-1 mutant and pgb2-aos1-1 double mutant declined, and was not rescued by increasing levels of NO stimulating embryogenesis in wild-type tissue. NO also influenced JA responses by up-regulating PLANT DEFENSIN 1 (PDF1) and JASMONATE-ZIM-PROTEIN (JAZ1), as well as down-regulating MYC2. The NO and JA modulation of MYC2 and JAZ1 controlled embryogenesis. Ectopic expression of JAZ1 or suppression of MYC2 promoted the formation of somatic embryos, while repression of JAZ1 and up-regulation of MYC2 reduced the embryogenic performance. Sustained expression of JAZ1 induced the transcription of several indole acetic acid (IAA) biosynthetic genes, resulting in higher IAA levels in the embryogenic cells. Collectively these data fit a model integrating JA in the PGB2 regulation of Arabidopsis embryogenesis. Suppression of PGB2 increases JA through NO. Elevated levels of JA repress MYC2 and induce JAZ1, favoring the accumulation of IAA in the explants and the subsequent production of somatic embryos. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  13. Isolation and functional characterization of a methyl jasmonate-responsive 3-carene synthase from Lavandula x intermedia.

    PubMed

    Adal, Ayelign M; Sarker, Lukman S; Lemke, Ashley D; Mahmoud, Soheil S

    2017-04-01

    A methyl jasmonate responsive 3-carene synthase (Li3CARS) gene was isolated from Lavandula x intermedia and functionally characterized in vitro. Lavenders produce essential oils consisting mainly of monoterpenes, including the potent antimicrobial and insecticidal monoterpene 3-carene. In this study we isolated and functionally characterized a leaf-specific, methyl jasmonate (MeJA)-responsive monoterpene synthase (Li3CARS) from Lavandula x intermedia. The ORF excluding transit peptides encoded a 64.9 kDa protein that was expressed in E. coli, and purified with Ni-NTA agarose affinity chromatography. The recombinant Li3CARS converted GPP into 3-carene as the major product, with K m and k cat of 3.69 ± 1.17 µM and 2.01 s(-1) respectively. Li3CARS also accepted NPP as a substrate to produce multiple products including a small amount of 3-carene. The catalytic efficiency of Li3CARS to produce 3-carene was over ten fold higher for GPP (k cat /K m = 0.56 µM(-1)s(-1)) than NPP (k cat /K m = 0.044 µM(-1)s(-1)). Production of distinct end product profiles from different substrates (GPP versus NPP) by Li3CARS indicates that monoterpene metabolism may be controlled in part through substrate availability. Li3CARS transcripts were found to be highly abundant in leaves (16-fold) as compared to flower tissues. The transcriptional activity of Li3CARS correlated with 3-carene production, and was up-regulated (1.18- to 3.8-fold) with MeJA 8-72 h post-treatment. The results suggest that Li3CARS may have a defensive role in Lavandula.

  14. Concurrent changes in methyl jasmonate emission and the expression of its biosynthesis-related genes in Cymbidium ensifolium flowers.

    PubMed

    Huang, Mingkun; Ma, Cuiping; Yu, Rangcai; Mu, Lanling; Hou, Jia; Yu, Yunyi; Fan, Yanping

    2015-04-01

    Methyl jasmonate (MeJA) is one of most abundant scent compounds in Cymbidium ensifolium flowers. In this study, the emission of MeJA and its regulation mechanism were investigated. Our results showed that emission of MeJA in C. ensifolium flowers was controlled developmentally and rhythmically. It occurred in a tissue-specific manner, and high MeJA emission was found in sepals and petals. A group of vital genes involved in the MeJA biosynthesis via the octadecanoid pathway were isolated from C. ensifolium flowers, including CeLOX, CeAOS, CeAOC and CeJMT. MeJA emission was at very low levels in unopened or half-opened C. ensifolium flowers and reached its maximal level between day 4 and 6 and declined from day 7 to 10 postanthesis. The expression of CeLOX, CeAOS, CeAOC and CeJMT increased from day 1 to day 6, and then declined from day 7 to 10 postanthesis, corresponding to the change in MeJA emission. Moreover, the expression of CeLOX, CeAOS, CeAOC and CeJMT oscillated in a rhythmic manner could reach the maximum level between 8:00 h and 16:00 h, which coincided with the MeJA emission. The high level of MeJA emission in sepals and petals coincided with the high transcript levels. The results suggest that MeJA emission in C. ensifolium flower might be directly regulated at the transcription levels. Moreover, the recombinant protein of CeJMT could specifically catalyze the jasmonic acid to form the corresponding ester MeJA.

  15. Late Implant Removal After Posterior Correction of AIS With Pedicle Screw Instrumentation-A Matched Case Control Study With 10-Year Follow-up.

    PubMed

    Farshad, Mazda; Sdzuy, Christoph; Min, Kan

    2013-01-01

    Matched case-control study. To find the amount of progression of deformity and its clinical consequences in the long term after implant removal (IR) as a result of late infection in adolescent idiopathic scoliosis (AIS). Late IR is occasionally necessary after instrumented posterior correction of AIS because of late implant infection or implant-associated pain. The long-term outcome is not yet known because of the lack of studies with a comparable control group. We observed 50 patients with AIS, who had pedicle screw instrumentation for posterior correction, for at least 10 years. Seven of these patients needed IR after 3.4 years (range, 1.1-7.9 years) years because of late implant-associated infection. We matched these patients with another 7 who had no complications (control), by curve type, Risser stage, age, and gender. We performed radiological measurements preoperatively, at 6 weeks, and 2, 5, and 10 years postoperatively. All patients completed the SRS-24 questionnaire at 2- and 10-year follow-up. Although the curve magnitude of the main thoracic curve was similar preoperatively (Cobb angle: IR, 57°±6°; control, 57°±10°) and corrected equally (IR, 18°±4°; control, 20°±7°) at 6 weeks, the deformity progressed in the IR group at 2 years (IR, 25°±11°; control, 17°±6°) and became statistically different at 10 years (IR, 31°±10°; control, 19°±6°; p<.05). There was no significant difference in total Scoliosis Research Society score between groups (IR, 99±13; control, 90±17; p>.05) at 10 years. Late implant removal after posterior correction of thoracic AIS with pedicle screw instrumentation results in a loss of Cobb angle correction of about one third in coronal plane at 10-year follow-up, but without clinical relevance, as measured by the Scoliosis Research Society-24 questionnaire. Copyright © 2013 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

  16. Microarray and differential display identify genes involved in jasmonate-dependent anther development.

    PubMed

    Mandaokar, Ajin; Kumar, V Dinesh; Amway, Matt; Browse, John

    2003-07-01

    Jasmonate (JA) is a signaling compound essential for anther development and pollen fertility in Arabidopsis. Mutations that block the pathway of JA synthesis result into male sterility. To understand the processes of anther and pollen maturation, we used microarray and differential display approaches to compare gene expression pattern in anthers of wild-type Arabidopsis and the male-sterile mutant, opr3. Microarray experiment revealed 25 genes that were up-regulated more than 1.8-fold in wild-type anthers as compared to mutant anthers. Experiments based on differential display identified 13 additional genes up-regulated in wild-type anthers compared to opr3 for a total of 38 differentially expressed genes. Searches of the Arabidopsis and non-redundant databases disclosed known or likely functions for 28 of the 38 genes identified, while 10 genes encode proteins of unknown function. Northern blot analysis of eight representative clones as probes confirmed low expression in opr3 anthers compared with wild-type anthers. JA responsiveness of these same genes was also investigated by northern blot analysis of anther RNA isolated from wild-type and opr3 plants, In these experiments, four genes were induced in opr3 anthers within 0.5-1 h of JA treatment while the remaining genes were up-regulated only 1-8 h after JA application. None of these genes was induced by JA in anthers of the coil mutant that is deficient in JA responsiveness. The four early-induced genes in opr3 encode lipoxygenase, a putative bHLH transcription factor, epithiospecifier protein and an unknown protein. We propose that these and other early components may be involved in JA signaling and in the initiation of developmental processes. The four late genes encode an extensin-like protein, a peptide transporter and two unknown proteins, which may represent components required later in anther and pollen maturation. Transcript profiling has provided a successful approach to identify genes involved in

  17. Heterotrimeric G Proteins Facilitate Arabidopsis Resistance to Necrotrophic Pathogens and Are Involved in Jasmonate Signaling1

    PubMed Central

    Trusov, Yuri; Rookes, James Edward; Chakravorty, David; Armour, David; Schenk, Peer Martin; Botella, José Ramón

    2006-01-01

    Heterotrimeric G proteinshave been previously linked to plant defense; however a role for the Gβγ dimer in defense signaling has not been described to date. Using available Arabidopsis (Arabidopsis thaliana) mutants lacking functional Gα or Gβ subunits, we show that defense against the necrotrophic pathogens Alternaria brassicicola and Fusarium oxysporum is impaired in Gβ-deficient mutants while Gα-deficient mutants show slightly increased resistance compared to wild-type Columbia ecotype plants. In contrast, responses to virulent (DC3000) and avirulent (JL1065) strains of Pseudomonas syringae appear to be independent of heterotrimeric G proteins. The induction of a number of defense-related genes in Gβ-deficient mutants were severely reduced in response to A. brassicicola infection. In addition, Gβ-deficient mutants exhibit decreased sensitivity to a number of methyl jasmonate-induced responses such as induction of the plant defensin gene PDF1.2, inhibition of root elongation, seed germination, and growth of plants in sublethal concentrations of methyl jasmonate. In all cases, the behavior of the Gα-deficient mutants is coherent with the classic heterotrimeric mechanism of action, indicating that jasmonic acid signaling is influenced by the Gβγ functional subunit but not by Gα. We hypothesize that Gβγ acts as a direct or indirect enhancer of the jasmonate signaling pathway in plants. PMID:16339801

  18. Methyl jasmonate deficiency alters cellular metabolome including the aminome of tomato (Solanum lycopersicum L.) fruit

    USDA-ARS?s Scientific Manuscript database

    Lipoxygenase (LOX) catalyzes oxidation of C-13 atom of C:18 polyunsaturated fatty acids and produces jasmonic acid and other oxylipins that have important biological relevance. However, the role of these important molecules in cellular metabolism is barely understood. We have used a transgenic appro...

  19. Effect of methyl jasmonate, salicylic acid, Headline and Stadium on sucrose yield and storage properties

    USDA-ARS?s Scientific Manuscript database

    Methyl jasmonate (MeJA) and salicylic acid (SA) have been reported to enhance yield and protect crop plants and products against abiotic stresses and diseases. The effect of these compounds on sugarbeets, however, is unknown. Research was initiated in 2014 to investigate the effects of an early seas...

  20. Differential impact of lipoxygenase 2 and jasmonates on natural and stress-induced senescence in Arabidopsis.

    PubMed

    Seltmann, Martin A; Stingl, Nadja E; Lautenschlaeger, Jens K; Krischke, Markus; Mueller, Martin J; Berger, Susanne

    2010-04-01

    Jasmonic acid and related oxylipins are controversially discussed to be involved in regulating the initiation and progression of leaf senescence. To this end, we analyzed profiles of free and esterified oxylipins during natural senescence and upon induction of senescence-like phenotypes by dark treatment and flotation on sorbitol in Arabidopsis (Arabidopsis thaliana). Jasmonic acid and free 12-oxo-phytodienoic acid increased during all three processes, with the strongest increase of jasmonic acid after dark treatment. Arabidopside content only increased considerably in response to sorbitol treatment. Monogalactosyldiacylglycerols and digalactosyldiacylglycerols decreased during these treatments and aging. Lipoxygenase 2-RNA interference (RNAi) plants were generated, which constitutively produce jasmonic acid and 12-oxo-phytodienoic acid but do not exhibit accumulation during natural senescence or upon stress treatment. Chlorophyll loss during aging and upon dark incubation was not altered, suggesting that these oxylipins are not involved in these processes. In contrast, lipoxygenase 2-RNAi lines and the allene oxid synthase-deficient mutant dde2 were less sensitive to sorbitol than the wild type, indicating that oxylipins contribute to the response to sorbitol stress.

  1. Jasmonate and salicylate induce expression of herbivore cytochrome P450 genes.

    PubMed

    Li, Xianchun; Schuler, Mary A; Berenbaum, May R

    2002-10-17

    Jasmonate and salicylate are plant-produced signals that activate plant defence genes after herbivory or pathogen attack. Amplification of these signals, evoked by either enemy attack or experimental manipulation, leads to an increase in the synthesis of toxic compounds (allelochemicals) and defence proteins in the plants. Although the jasmonate and salicylate signal cascades activate different sets of plant defence genes, or even act antagonistically, there is substantial communication between the pathways. Jasmonate and salicylate also contribute to protecting plants against herbivores by causing plants that experience insect damage to increase their production of volatile molecules that attract natural enemies of herbivorous insects. In response to plant defences, herbivores increase their production of enzymes that detoxify allelochemicals, including cytochrome P450s (refs 15, 16). But herbivores are potentially vulnerable to toxic allelochemicals in the duration between ingesting toxins and induction of detoxification systems. Here we show that the corn earworm Helicoverpa zea uses jasmonate and salicylate to activate four of its cytochrome P450 genes that are associated with detoxification either before or concomitantly with the biosynthesis of allelochemicals. This ability to 'eavesdrop' on plant defence signals protects H. zea against toxins produced by host plants.

  2. Priming of jasmonate-mediated anti-herbivore defense responses in rice by silicon

    USDA-ARS?s Scientific Manuscript database

    While the function of silicon (Si) in plant physiology has long been debated, its beneficial effects on plant resistance against abiotic and biotic stresses, ¬including insect herbivory, have been well-documented. In addition, the jasmonate (JA) signaling pathway plays a crucial role in mediating an...

  3. Effect of methyl jasmonate, salicylic acid, Headline and Stadium on sucrose yield and storage properties

    USDA-ARS?s Scientific Manuscript database

    Methyl jasmonate (MeJA) and salicylic acid (SA) have been reported to enhance yield and protect crop plants and products against abiotic stresses and diseases. The effect of these compounds on sugarbeets, however, is unknown. Research was conducted in 2015 and 2016 to investigate the effects of an e...

  4. Use of jasmonic acid and salicylic acid to inhibit growth of sugarbeet storage rot pathogens

    USDA-ARS?s Scientific Manuscript database

    Jasmonic acid (JA) and salicylic acid (SA) are endogenous plant hormones that induce native plant defense responses and provide protection against a wide range of diseases. Previously, JA, applied after harvest, was shown to protect sugarbeet roots against the storage pathogens, Botrytis cinerea, P...

  5. Expression of jasmonic ethylene responsive factor gene in transgenic poplar tree leads to increased salt tolerance.

    PubMed

    Li, Yiliang; Su, Xiaohua; Zhang, Bingyu; Huang, Qinjun; Zhang, Xianghua; Huang, Rongfeng

    2009-02-01

    The stress resistance of plants can be enhanced by regulating the expression of multiple downstream genes associated with stress resistance. We used the Agrobacterium method to transfer the tomato jasmonic ethylene responsive factors (JERFs) gene that encodes the ethylene response factor (ERF) like transcription factor to the genome of a hybrid poplar (Populus alba x Populus berolinensis). Eighteen resistant plants were obtained, of which 13 were identified by polymerase chain reaction (PCR), reverse transcriptase PCR and Southern blot analyses as having incorporated the JERFs gene and able to express it at the transcriptional level. Salinity tests were conducted in a greenhouse with 0, 100, 200 and 300 mM NaCl. In the absence of NaCl, the transgenic plants were significantly taller than the control plants, but no statistically significant differences in the concentrations of proline and chlorophyll were observed. With increasing salinity, the extent of damage was significantly less in transgenic plants than that in control plants, and the reductions in height, basal diameter and biomass were less in transgenic plants than those in control plants. At 200 and 300 mM NaCl concentrations, transgenic plants were 128.9% and 98.8% taller, respectively, and had 199.8% and 113.0% more dry biomass, respectively, than control plants. The saline-induced reduction in leaf water content and increase in root/crown ratio were less in transgenic plants than in control plants. Foliar proline concentration increased more in response to salt treatment in transgenic plants than in control plants. Foliar Na(+) concentration was higher in transgenic plants than in control plants. In the coastal area in Panjin of Liaoning where the total soil salt concentration is 0.3%, a salt tolerance trial of transgenic plants indicated that 3-year-old transgenic plants were 14.5% and 33.6% taller than the control plants at two field sites. The transgenic plants at the two field sites were growing

  6. Higher Education Is an Age-Independent Predictor of White Matter Integrity and Cognitive Control in Late Adolescence

    ERIC Educational Resources Information Center

    Noble, Kimberly G.; Korgaonkar, Mayuresh S.; Grieve, Stuart M.; Brickman, Adam M.

    2013-01-01

    Socioeconomic status is an important predictor of cognitive development and academic achievement. Late adolescence provides a unique opportunity to study how the attainment of socioeconomic status (in the form of years of education) relates to cognitive and neural development, during a time when age-related cognitive and neural development is…

  7. Landscape- vs gap-level controls on the abundance of a fire-sensitive, late-successional tree species.

    Treesearch

    Michael C. Wimberly; Thomas A. Spies

    2002-01-01

    Tsuga heterophylla (western hemlock), a fire-sensitive, late-successional tree species, is an important component of old-growth forests in the Pacific Northwest, USA. In the Oregon Coast Range, however, T. heterophylla occurs at low densities in or is completely absent from many conifer stands. We used a cellular automata-based...

  8. Assessment of a Standardized Pre-Operative Telephone Checklist Designed to Avoid Late Cancellation of Ambulatory Surgery: The AMBUPROG Multicenter Randomized Controlled Trial

    PubMed Central

    Marchand-Maillet, Florence; Baron, Gabriel; Douard, Richard; Béthoux, Jean-Pierre

    2016-01-01

    Objectives To assess the impact of a standardized pre-operative telephone checklist on the rate of late cancellations of ambulatory surgery (AMBUPROG trial). Design Multicenter, two-arm, parallel-group, open-label randomized controlled trial. Setting 11 university hospital ambulatory surgery units in Paris, France. Participants Patients scheduled for ambulatory surgery and able to be reached by telephone. Intervention A 7-item checklist designed to prevent late cancellation, available in five languages and two versions (for children and adults), was administered between 7 and 3 days before the planned date of surgery, by an automated phone system or a research assistant. The control group received standard management alone. Main Outcome Measures Rate of cancellation on the day of surgery or the day before. Results The study population comprised 3900 patients enrolled between November 2012 and September 2013: 1950 patients were randomized to the checklist arm and 1950 patients to the control arm. The checklist was administered to 68.8% of patients in the intervention arm, 1002 by the automated phone system and 340 by a research assistant. The rate of late cancellation did not differ significantly between the checklist and control arms (109 (5.6%) vs. 113 (5.8%), adjusted odds ratio [95% confidence interval] = 0.91 [0.65–1.29], (p = 0.57)). Checklist administration revealed that 355 patients (28.0%) had not undergone tests ordered by the surgeon or anesthetist, and that 254 patients (20.0%) still had questions concerning the fasting state. Conclusions A standardized pre-operative telephone checklist did not avoid late cancellations of ambulatory surgery but enabled us to identify several frequent causes. Trial Registration ClinicalTrials.gov NCT01732159 PMID:26829478

  9. Wound and insect-induced jasmonate accumulation in carnivorous Drosera capensis: two sides of the same coin.

    PubMed

    Mithöfer, A; Reichelt, M; Nakamura, Y

    2014-09-01

    Carnivorous sundew plants catch and digest insect prey for their own nutrition. The sundew species Drosera capensis shows a pronounced leaf bending reaction upon prey capture in order to form an 'outer stomach'. This formation is triggered by jasmonates, phytohormones typically involved in defence reactions against herbivory and wounding. Whether jasmonates still have this function in D. capensis in addition to mediating the leaf bending reaction was investigated here. Wounded, insect prey-fed and insect-derived oral secretion-treated leaves of D. capensis were analysed for jasmonates (jasmonic acid, JA; jasmonic acid-isoleucine conjugate, JA-Ile) using LC-MS/MS. Prey-induced jasmonate accumulation in D. capensis leaves was persistent, and showed high levels of JA and JA-Ile (575 and 55.7 pmol · g · FW(-1) , respectively), whereas wounding induced a transient increase of JA (maximum 500 pmol · g · FW(-1) ) and only low (3.1 pmol · g · FW(-1) ) accumulation of JA-Ile. Herbivory, mimicked with a combined treatment of wounding plus oral secretion (W+OS) obtained from Spodoptera littoralis larvae induced both JA (4000 pmol · g · FW(-1) ) and JA-Ile (25 pmol · g · FW(-1) ) accumulation, with kinetics similar to prey treatment. Only prey and W+OS, but not wounding alone or OS, induced leaf bending. The results indicate that both mechanical and chemical stimuli trigger JA and JA-Ile synthesis. Differences in kinetics and induced jasmonate levels suggest different sensing and signalling events upon injury and insect-dependent challenge. Thus, in Drosera, jasmonates are still part of the response to wounding. Jasmonates are also employed in insect-induced reactions, including responses to herbivory and carnivory.

  10. Structural basis of JAZ repression of MYC transcription factors in jasmonate signalling

    DOE PAGES

    Zhang, Feng; Yao, Jian; Ke, Jiyuan; ...

    2015-08-10

    The plant hormone jasmonate plays crucial roles in regulating plant responses to herbivorous insects and microbial pathogens and is an important regulator of plant growth and development. Key mediators of jasmonate signalling include MYC transcription factors, which are repressed by jasmonate ZIM-domain (JAZ) transcriptional repressors in the resting state. In the presence of active jasmonate, JAZ proteins function as jasmonate co-receptors by forming a hormone-dependent complex with COI1, the F-box subunit of an SCF-type ubiquitin E3 ligase. The hormone-dependent formation of the COI1–JAZ co-receptor complex leads to ubiquitination and proteasome-dependent degradation of JAZ repressors and release of MYC proteins frommore » transcriptional repression. The mechanism by which JAZ proteins repress MYC transcription factors and how JAZ proteins switch between the repressor function in the absence of hormone and the co-receptor function in the presence of hormone remain enigmatic. In this paper, we show that Arabidopsis MYC3 undergoes pronounced conformational changes when bound to the conserved Jas motif of the JAZ9 repressor. The Jas motif, previously shown to bind to hormone as a partly unwound helix, forms a complete α-helix that displaces the amino (N)-terminal helix of MYC3 and becomes an integral part of the MYC N-terminal fold. In this position, the Jas helix competitively inhibits MYC3 interaction with the MED25 subunit of the transcriptional Mediator complex. Finally, our structural and functional studies elucidate a dynamic molecular switch mechanism that governs the repression and activation of a major plant hormone pathway.« less

  11. Exploring Jasmonates in the Hormonal Network of Drought and Salinity Responses

    PubMed Central

    Riemann, Michael; Dhakarey, Rohit; Hazman, Mohamed; Miro, Berta; Kohli, Ajay; Nick, Peter

    2015-01-01

    Present and future food security is a critical issue compounded by the consequences of climate change on agriculture. Stress perception and signal transduction in plants causes changes in gene or protein expression which lead to metabolic and physiological responses. Phytohormones play a central role in the integration of different upstream signals into different adaptive outputs such as changes in the activity of ion-channels, protein modifications, protein degradation, and gene expression. Phytohormone biosynthesis and signaling, and recently also phytohormone crosstalk have been investigated intensively, but the function of jasmonates under abiotic stress is still only partially understood. Although most aspects of jasmonate biosynthesis, crosstalk and signal transduction appear to be similar for biotic and abiotic stress, novel aspects have emerged that seem to be unique for the abiotic stress response. Here, we review the knowledge on the role of jasmonates under drought and salinity. The crosstalk of jasmonate biosynthesis and signal transduction pathways with those of abscisic acid (ABA) is particularly taken into account due to the well-established, central role of ABA under abiotic stress. Likewise, the accumulating evidence of crosstalk of jasmonate signaling with other phytohormones is considered as important element of an integrated phytohormonal response. Finally, protein post-translational modification, which can also occur without de novo transcription, is treated with respect to its implications for phytohormone biosynthesis, signaling and crosstalk. To breed climate-resilient crop varieties, integrated understanding of the molecular processes is required to modulate and tailor particular nodes of the network to positively affect stress tolerance. PMID:26648959

  12. Structural basis of JAZ repression of MYC transcription factors in jasmonate signalling

    SciTech Connect

    Zhang, Feng; Yao, Jian; Ke, Jiyuan; Zhang, Li; Lam, Vinh Q.; Xin, Xiu-Fang; Zhou, X. Edward; Chen, Jian; Brunzelle, Joseph; Griffin, Patrick R.; Zhou, Mingguo; Xu, H. Eric; Melcher, Karsten; He, Sheng Yang

    2015-08-10

    The plant hormone jasmonate plays crucial roles in regulating plant responses to herbivorous insects and microbial pathogens and is an important regulator of plant growth and development. Key mediators of jasmonate signalling include MYC transcription factors, which are repressed by jasmonate ZIM-domain (JAZ) transcriptional repressors in the resting state. In the presence of active jasmonate, JAZ proteins function as jasmonate co-receptors by forming a hormone-dependent complex with COI1, the F-box subunit of an SCF-type ubiquitin E3 ligase. The hormone-dependent formation of the COI1–JAZ co-receptor complex leads to ubiquitination and proteasome-dependent degradation of JAZ repressors and release of MYC proteins from transcriptional repression. The mechanism by which JAZ proteins repress MYC transcription factors and how JAZ proteins switch between the repressor function in the absence of hormone and the co-receptor function in the presence of hormone remain enigmatic. In this paper, we show that Arabidopsis MYC3 undergoes pronounced conformational changes when bound to the conserved Jas motif of the JAZ9 repressor. The Jas motif, previously shown to bind to hormone as a partly unwound helix, forms a complete α-helix that displaces the amino (N)-terminal helix of MYC3 and becomes an integral part of the MYC N-terminal fold. In this position, the Jas helix competitively inhibits MYC3 interaction with the MED25 subunit of the transcriptional Mediator complex. Finally, our structural and functional studies elucidate a dynamic molecular switch mechanism that governs the repression and activation of a major plant hormone pathway.

  13. Transcriptional Responses and Gentiopicroside Biosynthesis in Methyl Jasmonate-Treated Gentiana macrophylla Seedlings

    PubMed Central

    Cao, Xiaoyan; Guo, Xiaorong; Yang, Xinbing; Wang, Huaiqin; Hua, Wenping; He, Yihan; Kang, Jiefang; Wang, Zhezhi

    2016-01-01

    Gentiana macrophylla, a medicinal plant with significant pharmacological properties, contains the bioactive compound gentiopicroside. Methyl jasmonate (MeJA) is an effective elicitor for enhancing the production of such compounds. However, little is known about MeJA-mediated biosynthesis of gentiopicroside. We investigated this phenomenon as well as gene expression profiles to determine the molecular mechanisms for MeJA-mediated gentiopicroside biosynthesis and regulation in G. macrophylla. Our HPLC results showed that Gentiana macrophylla seedlings exposed to MeJA had significantly higher concentrations of gentiopicroside when compared with control plants. We used RNA sequencing to compare transcriptional profiles in seedlings treated for 5 d with either 0 μmol L-1 MeJA (C) or 250 μmol L-1 MeJA (M5) and detected differentially expressed genes (DEGs). In total, 77,482 unique sequences were obtained from approximately 34 million reads. Of these, 48,466 (57.46%) sequences were annotated based on BLASTs performed against public databases. We identified 5,206 DEGs between the C and M5 samples, including genes related to the α-lenolenic acid degradation pathway, JA signaling pathway, and gentiopicroside biosynthesis. Expression of numerous enzyme genes in the glycolysis pathway was significantly up-regulated. Many genes encoding transcription factors (e.g. ERF, bHLH, MYB, and WRKY) also responded to MeJA elicitation. Rapid acceleration of the glycolysis pathway that supplies precursors for IPP biosynthesis and up-regulates the expression of enzyme genes in that IPP pathway are probably most responsible for MeJA stimulation of gentiopicroside synthesis. Our qRT-PCR results showed that the expression profiles of 12 gentiopicroside biosynthesis genes were consistent with the RNA-Seq data. These results increase our understanding about how the gentiopicroside biosynthesis pathway in G. macrophylla responds to MeJA. PMID:27851826

  14. Priming of jasmonate-mediated antiherbivore defense responses in rice by silicon.

    PubMed

    Ye, Mao; Song, Yuanyuan; Long, Jun; Wang, Ruilong; Baerson, Scott R; Pan, Zhiqiang; Zhu-Salzman, Keyan; Xie, Jiefen; Cai, Kunzheng; Luo, Shiming; Zeng, Rensen

    2013-09-17

    Although the function of silicon (Si) in plant physiology has long been debated, its beneficial effects on plant resistance against abiotic and biotic stresses, including insect herbivory, have been well documented. In addition, the jasmonate (JA) signaling pathway plays a crucial role in mediating antiherbivore defense responses in plants. However, potential interactions between JA and Si in response to insect attack have not been examined directly. To explore the role JA may play in Si-enhanced resistance, we silenced the expression of allene oxide synthase (OsAOS; active in JA biosynthesis) and CORONATINE INSENSITIVE1 (OsCOI1; active in JA perception) genes in transgenic rice plants via RNAi and examined resulting changes in Si accumulation and defense responses against caterpillar Cnaphalocrocis medinalis (rice leaffolder, LF) infestation. Si pretreatment increased rice resistance against LF larvae in wild-type plants but not in OsAOS and OsCOI1 RNAi lines. Upon LF attack, wild-type plants subjected to Si pretreatment exhibited enhanced defense responses relative to untreated controls, including higher levels of JA accumulation; increased levels of transcripts encoding defense marker genes; and elevated activities of peroxidase, polyphenol oxidase, and trypsin protease inhibitor. Additionally, reduced Si deposition and Si cell expansion were observed in leaves of OsAOS and OsCOI1 RNAi plants in comparison with wild-type plants, and reduced steady-state transcript levels of the Si transporters OsLsi1, OsLsi2, and OsLsi6 were observed in Si-pretreated plants after LF attack. These results suggest a strong interaction between Si and JA in defense against insect herbivores involving priming of JA-mediated defense responses by Si and the promotion of Si accumulation by JA.

  15. Priming of jasmonate-mediated antiherbivore defense responses in rice by silicon

    PubMed Central

    Ye, Mao; Song, Yuanyuan; Long, Jun; Wang, Ruilong; Baerson, Scott R.; Pan, Zhiqiang; Zhu-Salzman, Keyan; Xie, Jiefen; Cai, Kunzheng; Luo, Shiming; Zeng, Rensen

    2013-01-01

    Although the function of silicon (Si) in plant physiology has long been debated, its beneficial effects on plant resistance against abiotic and biotic stresses, including insect herbivory, have been well documented. In addition, the jasmonate (JA) signaling pathway plays a crucial role in mediating antiherbivore defense responses in plants. However, potential interactions between JA and Si in response to insect attack have not been examined directly. To explore the role JA may play in Si-enhanced resistance, we silenced the expression of allene oxide synthase (OsAOS; active in JA biosynthesis) and CORONATINE INSENSITIVE1 (OsCOI1; active in JA perception) genes in transgenic rice plants via RNAi and examined resulting changes in Si accumulation and defense responses against caterpillar Cnaphalocrocis medinalis (rice leaffolder, LF) infestation. Si pretreatment increased rice resistance against LF larvae in wild-type plants but not in OsAOS and OsCOI1 RNAi lines. Upon LF attack, wild-type plants subjected to Si pretreatment exhibited enhanced defense responses relative to untreated controls, including higher levels of JA accumulation; increased levels of transcripts encoding defense marker genes; and elevated activities of peroxidase, polyphenol oxidase, and trypsin protease inhibitor. Additionally, reduced Si deposition and Si cell expansion were observed in leaves of OsAOS and OsCOI1 RNAi plants in comparison with wild-type plants, and reduced steady-state transcript levels of the Si transporters OsLsi1, OsLsi2, and OsLsi6 were observed in Si-pretreated plants after LF attack. These results suggest a strong interaction between Si and JA in defense against insect herbivores involving priming of JA-mediated defense responses by Si and the promotion of Si accumulation by JA. PMID:24003150

  16. Exogenous jasmonic acid can enhance tolerance of wheat seedlings to salt stress.

    PubMed

    Qiu, ZongBo; Guo, JunLi; Zhu, AiJing; Zhang, Liang; Zhang, ManMan

    2014-06-01

    Jasmonic acid (JA) is regarded as endogenous regulator that plays an important role in regulating stress responses, plant growth and development. To investigate the physiological mechanisms of salt stress mitigated by exogenous JA, foliar application of 2mM JA was done to wheat seedlings for 3days and then they were subjected to 150mM NaCl. Our results showed that 150mM NaCl treatment significantly decreased plant height, root length, shoot dry weight, root dry weight, the concentration of glutathione (GSH), chlorophyll b (Chl b) and carotenoid (Car), the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), enhanced the concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2) and the rate of superoxide radical (O2•-) generation in the wheat seedlings when compared with the control. However, treatments with exogenous JA for 3 days significantly enhanced salt stress tolerance in wheat seedlings by decreasing the concentration of MDA and H2O2, the production rate of O2•- and increasing the transcript levels and activities of SOD, POD, CAT and APX and the contents of GSH, Chl b and Car, which, in turn, enhanced the growth of salt stressed seedlings. These results suggested that JA could effectively protect wheat seedlings from salt stress damage by enhancing activities of antioxidant enzymes and the concentration of antioxidative compounds to quench the excessive reactive oxygen species caused by salt stress and presented a practical implication for wheat cultivation in salt-affected soils. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Root and shoot jasmonic acid applications differentially affect leaf chemistry and herbivore growth

    PubMed Central

    Oomen, Mariëlle WAT

    2008-01-01

    Many induced responses in plants are systemic. Therefore, root-induced responses may alter leaf quality for shoot herbivores. Previously, we found that root and shoot application of jasmonic acid (JA) to feral Brassica oleracea both induced glucosinolates in the leaves. However, the types of glucosinolates that increased in root- and shoot induced plants were different. Here we analyse whether primary metabolites, such as sugars and amino acids, are also differentially affected. Moreover, we test whether chemical differences in root- and shoot-induced plants differentially affect growth of the generalist Mamestra brassicae and the specialist Pieris rapae. Comprehensive analysis of glucosinolates, amino acid and sugars with principal component analysis revealed that leaf chemical profiles were affected both by JA application and by the organ that was induced. Shoot-induction increased indole glucosinolates, whereas root-induction induced aliphatic glucosinolates in the leaves. Leaves of shoot-induced plants had lower total sugar and total amino acid levels, whereas in root-induced plants only total sugar levels were significantly decreased. (Iso)leucine responded significantly different from the general trend, which allowed us to discuss the potential role of Myb transcription factors which are coordinating JA-induced glucosinolate and amino acid responses in Arabidopsis thaliana. Both M. brassicae and P. rapae grew the slowest on leaves of shoot-induced plants. M. brassicae growth and survival was also reduced on root-induced plants, whereas P. rapae growth on these plants was similar to that on controls. Specialist and generalist herbivores thus are differentially affected by the chemical changes after root and shoot-JA application. PMID:19516980

  18. Jasmonic Acid Enhances Al-Induced Root Growth Inhibition1[OPEN

    PubMed Central

    Yang, Zhong-Bao; Ma, Yanqi

    2017-01-01

    Phytohormones such as ethylene and auxin are involved in the regulation of the aluminum (Al)-induced root growth inhibition. Although jasmonate (JA) has been reported to play a crucial role in the regulation of root growth and development in response to environmental stresses through interplay with ethylene and auxin, its role in the regulation of root growth response to Al stress is not yet known. In an attempt to elucidate the role of JA, we found that exogenous application of JA enhanced the Al-induced root growth inhibition. Furthermore, phenotype analysis with mutants defective in either JA biosynthesis or signaling suggests that JA is involved in the regulation of Al-induced root growth inhibition. The expression of the JA receptor CORONATINE INSENSITIVE1 (COI1) and the key JA signaling regulator MYC2 was up-regulated in response to Al stress in the root tips. This process together with COI1-mediated Al-induced root growth inhibition under Al stress was controlled by ethylene but not auxin. Transcriptomic analysis revealed that many responsive genes under Al stress were regulated by JA signaling. The differential responsive of microtubule organization-related genes between the wild-type and coi1-2 mutant is consistent with the changed depolymerization of cortical microtubules in coi1 under Al stress. In addition, ALMT-mediated malate exudation and thus Al exclusion from roots in response to Al stress was also regulated by COI1-mediated JA signaling. Together, this study suggests that root growth inhibition is regulated by COI1-mediated JA signaling independent from auxin signaling and provides novel insights into the phytohormone-mediated root growth inhibition in response to Al stress. PMID:27932419

  19. Antidepressant-like activity of methyl jasmonate involves modulation of monoaminergic pathways in mice.

    PubMed

    Umukoro, Solomon; Adebesin, Adaeze; Agu, Gladys; Omorogbe, Osarume; Asehinde, Stephen Babajide

    2017-08-14

    The efficacy of current antidepressant drugs has been compromised by adverse effects, low remission and delay onset of action necessitating the search for alternative agents. Methyl jasmonate (MJ), a bioactive compound isolated from Jasminum grandiflorum has been shown to demonstrate antidepressant activity but its mechanism of action remains unknown. Thus, the role of monoaminergic systems in the antidepression-like activity of MJ was investigated in this study. Mice were given i.p. injection of MJ (5, 10 and 20mg/kg), imipramine (10mg/kg) and vehicle (10mL/kg) 30min before the forced swim test (FST) and tail suspension test (TST) were carried out. The involvement of monoaminergic systems in the anti-depressant-like effect of MJ (20mg/kg) was evaluated using p-chlorophenylalanine (pCPA), metergoline, yohimbine, prazosin, sulpiride and haloperidol in the TST. MJ significantly decrease the duration of immobility in the FST and TST relative to control suggesting antidepressant-like property. However, pretreatment with yohimbine (1mg/kg, i.p., an α2-adrenergic receptor antagonist) or prazosin (62.5μg/kg, i.p., an α1-adrenoceptor antagonist) attenuated the antidepressant-like activity of MJ. Also, pCPA; an inhibitor of serotonin biosynthesis (100mg/kg, i.p) or metergoline (4mg/kg, i.p., 5-HT2 receptor antagonist) reversed the anti-immobility effect of MJ. Sulpiride (50mg/kg, i.p., a D2 receptor antagonist) or haloperidol (0.2mg/kg, i.p., a dopamine receptor antagonist) reversed the anti-immobility effect of MJ. The results of this study suggest that serotonergic, noradrenergic and dopaminergic systems may play a role in the antidepressant-like activity of MJ. Copyright © 2017. Published by Elsevier B.V.

  20. Chemotype-dependent metabolic response to methyl jasmonate elicitation in Artemisia annua.

    PubMed

    Wu, Wei; Yuan, Man; Zhang, Qing; Zhu, Yanming; Yong, Li; Wang, Wei; Qi, Yan; Guo, Dianjing

    2011-07-01

    Considerable difference in artemisinin and its direct precursors, artemisinic acid and dihydroartemisinic acid, was detected between two chemotypes within the species Artemisia annua (A. annua). These two chemotypes showed differential metabolic response to methyl jasmonate (MeJA) elicitation. Exogenous application of MeJA resulted in an accumulation of dihydroartemisinic acid and artemisinin in Type I plants. In Type II plants, however, artemisinic acid and artemisinin level decreased dramatically under MeJA elicitation. Squalene and other sesquiterpenes, (e.g., caryophyllene, germacrene D), were stimulated by MeJA in both chemotypes. The effect of MeJA elicitation was also studied at the transcription level. Real time RT-PCR analysis showed a coordinated activation of most artemisinin pathway genes by MeJA in Type I plants. The lack of change in cytochrome P450 reductase (CPR) transcript in Type I plants indicates that the rate-limiting enzymes in artemisinin biosynthesis have yet to be identified. Other chemotype-specific electron donor proteins likely exist in A. annua to meet the demand for P450-mediated reactions in MeJA-mediated cellular processes. In Type II plants, mRNA expression patterns of most pathway genes were consistent with the reduced artemisinin level. Intriguingly, the mRNA transcript of aldehyde dehydrogenase1 (ADHL1), an enzyme which catalyzes the oxidation of artemisinic and dihydroartemisinic aldehydes, was upregulated by MeJA. The differential metabolic response to MeJA suggests a chemotype-dependent metabolic flux control towards artemisinin and sterol production in the species A. annua. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Tectonic and sedimentary evolution from the Late Sinian to Early Cambrian and their control on hydrocarbon source rocks in Tarim Basin, Western China

    NASA Astrophysics Data System (ADS)

    Wu, Lin

    2017-04-01

    The lower Cambrian black shale is widely distributed all over the world, but due to the deep buried depth of Cambrian in the Tarim Basin, the black shale, as high-quality source rocks, has never been found in the interior of the basin. Through further survey on outcrops in the periphery of the Tarim Basin, a set of hydrocarbon source rocks with high-quality was found developed at the bottom of the lower Cambrian Yuertusi formation in Tarim basin. Lithology of the source rock is black shale. Its organic carbon (TOC) mainly ranges 2-10%, organic carbon of black shale layer reaches 17%, and the thickness of outcrop is 10-15m in Aksu area. This discovery of hydrocarbon source rocks draws much attention to the oil and gas exploration in Cambrian. The author, integrating with seismic, drilling and geological data, analyzes the tectonic sedimentary evolution in late Sinian-early Cambrian in the basin and its control on formation and distribution of hydrocarbon source rocks in Early Cambrian in this paper. The Nanhua - early Sinian clastic rocks rift basin formed on the basement on Tarim under the control of Rodinia supercontinent tectonic movement. Post-rifting marine carbonate siliceous shale deposited from the late Sinian to Early Cambrian rifting. Wide transgression in Tarim in the late Sinian departed Tarim into two patterns in North and South with the central land as a boundary with structural features: higher topography in middle and lower topography in two sides. There was no change in the pattern of basin during the late Sinian tectonic movement, and the Cambrian sediments deposited and filled the basin in this period. The central ancient land with structural high topography formed angular unconformity, while the basin with low topography formed parallel unconformity. Therefore, the Early Cambrian sedimentary filling in the late Sinian basin overlapped from low topography to high topography. Their distribution patterns were similar, both of which were of great

  2. Intake of key micronutrients and food groups in patients with late-stage age-related macular degeneration compared with age-sex-matched controls.

    PubMed

    Gopinath, Bamini; Liew, Gerald; Russell, Joanna; Cosatto, Victoria; Burlutsky, George; Mitchell, Paul

    2017-08-01

    Knowledge of the risk factor profile of patients presenting with late-stage age-related macular degeneration (AMD) could help identify the most frequent modifiable AMD precursors among people who are referred for treatment. We aimed to assess dietary behaviours by comparing adjusted mean intakes of micronutrients and major food groups (fruits, vegetables, fish) among patients with AMD and a sample of age-sex-matched controls. Cross-sectional analysis of 480 late AMD cases and 518 population-based age-sex-matched controls with no AMD signs. AMD cases (aged 60+ years) were those presenting for treatment to a hospital eye clinic in Sydney, Australia, during 2012-2015. The comparator group were obtained from a cohort study (Blue Mountains Eye Study; Sydney, Australia) during 2002-2009. Dietary intake was assessed using a semiquantitative food-frequency questionnaire. AMD lesions were assessed from retinal photographs. After multivariable adjustment, patients with late-stage AMD compared with controls had significantly lower intakes of vitamin E (7.4 vs 9.8 mg/day; p<0.0001), beta-carotene (6232 vs 7738 μg/day; p<0.0001), vitamin C (161 vs 184 mg/day; p=0.0002) and folate (498.3 vs 602 μg/day; p<0.0001); but had higher intakes of zinc (13.0 vs 11.9 mg/day; p<0.0001). A significantly lower proportion of patients with late AMD met the recommended intake of vegetables than controls: 52.9% versus 64.5%; p=0.0002. This study showed significant differences in intakes of vitamins C and E, beta-carotene, folate and vegetables between patients with late-stage AMD and healthy controls, and thus has provided a better understanding of the nutritional intake of patients presenting with advanced AMD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. Arabidopsis CYP94B3 encodes jasmonyl-L-isoleucine 12-hydroxylase, a key enzyme in the oxidative catabolism of jasmonate.

    PubMed

    Kitaoka, Naoki; Matsubara, Takuya; Sato, Michio; Takahashi, Kosaku; Wakuta, Shinji; Kawaide, Hiroshi; Matsui, Hirokazu; Nabeta, Kensuke; Matsuura, Hideyuki

    2011-10-01

    The hormonal action of jasmonate in plants is controlled by the precise balance between its biosynthesis and catabolism. It has been shown that jasmonyl-L-isoleucine (JA-Ile) is the bioactive form involved in the jasmonate-mediated signaling pathway. However, the catabolism of JA-Ile is poorly understood. Although a metabolite, 12-hydroxyJA-Ile, has been characterized, detailed functional studies of the compound and the enzyme that produces it have not been conducted. In this report, the kinetics of wound-induced accumulation of 12-hydroxyJA-Ile in plants were examined, and its involvement in the plant wound response is described. Candidate genes for the catabolic enzyme were narrowed down from 272 Arabidopsis Cyt P450 genes using Arabidopsis mutants. The candidate gene was functionally expressed in Pichia pastoris to reveal that CYP94B3 encodes JA-Ile 12-hydroxylase. Expression analyses demonstrate that expression of CYP94B3 is induced by wounding and shows specific activity toward JA-Ile. Plants grown in medium containing JA-Ile show higher sensitivity to JA-Ile in cyp94b3 mutants than in wild-type plants. These results demonstrate that CYP94B3 plays a major regulatory role in controlling the level of JA-Ile in plants.

  4. Controls of late Palaeozoic and Mesozoic extension in the British Isles: evidence from seismic reflection data in the Central North Sea

    NASA Astrophysics Data System (ADS)

    Smith, K.; Cameron, T. D. J.

    2009-04-01

    Controls of late Palaeozoic and Mesozoic extension in the British Isles: evidence from seismic reflection data in the Central North Sea. Kevin Smith (1) and Don Cameron (2) (1) British Geological Survey, Murchison House, West Mains Road, Edinburgh, EH9 3LA. (ksm@bgs.ac.uk). (2) British Geological Survey, 376 Gilmerton Road, Edinburgh, EH17 7QS. In the area of the British Isles during the late Devonian and early Carboniferous, the oblique convergence of Laurentia and Gondwana imposed a torque on the adjoining terranes of Baltica and Avalonia. Their resulting clockwise rotation was accommodated by widely distributed N-S extension in the intervening zones previously formed by Caledonian and Acadian convergence. South of Laurentia and Baltica, late Palaeozoic extension was focused (1) at terrane margins, (2) in areas of limited Caledonian-Acadian plutonism, and (3) in places where the western (Iapetus) and eastern (Tornquist) convergence zones intersect at a high angle. One of these latter areas lies in Central England immediately north of the Midland Microcraton (part of Eastern Avalonia), where thermal subsidence associated with early Carboniferous extension gave rise to the late Carboniferous Pennine Basin. Interpretation of an extensive set of 3D and 2D long-offset seismic reflection data suggests that a similar area of enhanced extension at a fold belt intersection lies to north of the Mid North Sea High in the middle of the Central North Sea. Variscan uplift and inversion of the late Palaeozoic basins began to predominate in mid-Carboniferous times as final amalgamation of all the different terranes to form Pangaea curtailed the initial episode of extension and thermal subsidence. This change in the tectonic regime was associated with the onset of tholeiitic volcanism within the convergence zones, and was followed by localised extension during the earliest Permian. Evidence obtained from seismic interpretation of the deep structure of the UK sector of the Central

  5. Basic Helix-Loop-Helix Transcription Factors JASMONATE-ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3 Are Negative Regulators of Jasmonate Responses in Arabidopsis1[W][OPEN

    PubMed Central

    Sasaki-Sekimoto, Yuko; Jikumaru, Yusuke; Obayashi, Takeshi; Saito, Hikaru; Masuda, Shinji; Kamiya, Yuji; Ohta, Hiroyuki; Shirasu, Ken

    2013-01-01

    Jasmonates regulate transcriptional reprogramming during growth, development, and defense responses. Jasmonoyl-isoleucine, an amino acid conjugate of jasmonic acid (JA), is perceived by the protein complex composed of the F-box protein CORONATINE INSENSITIVE1 (COI1) and JASMONATE ZIM DOMAIN (JAZ) proteins, leading to the ubiquitin-dependent degradation of JAZ proteins. This activates basic helix-loop-helix-type MYC transcription factors to regulate JA-responsive genes. Here, we show that the expression of genes encoding other basic helix-loop-helix transcription factors, JASMONATE ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3, is positively regulated in a COI1- and MYC2-dependent manner in Arabidopsis (Arabidopsis thaliana). However, contrary to myc2, the jam1jam2jam3 triple mutant exhibited shorter roots when treated with methyl jasmonate (MJ), indicating enhanced responsiveness to JA. Our genome-wide expression analyses revealed that key jasmonate metabolic genes as well as a set of genes encoding transcription factors that regulate the JA-responsive metabolic genes are negatively regulated by JAMs after MJ treatment. Consistently, loss of JAM genes resulted in higher accumulation of anthocyanin in MJ-treated plants as well as higher accumulation of JA and 12-hydroxyjasmonic acid in wounded plants. These results show that JAMs negatively regulate the JA responses in a manner that is mostly antagonistic to MYC2. PMID:23852442

  6. Basic helix-loop-helix transcription factors JASMONATE-ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3 are negative regulators of jasmonate responses in Arabidopsis.

    PubMed

    Sasaki-Sekimoto, Yuko; Jikumaru, Yusuke; Obayashi, Takeshi; Saito, Hikaru; Masuda, Shinji; Kamiya, Yuji; Ohta, Hiroyuki; Shirasu, Ken

    2013-09-01

    Jasmonates regulate transcriptional reprogramming during growth, development, and defense responses. Jasmonoyl-isoleucine, an amino acid conjugate of jasmonic acid (JA), is perceived by the protein complex composed of the F-box protein CORONATINE INSENSITIVE1 (COI1) and JASMONATE ZIM DOMAIN (JAZ) proteins, leading to the ubiquitin-dependent degradation of JAZ proteins. This activates basic helix-loop-helix-type MYC transcription factors to regulate JA-responsive genes. Here, we show that the expression of genes encoding other basic helix-loop-helix transcription factors, JASMONATE ASSOCIATED MYC2-LIKE1 (JAM1), JAM2, and JAM3, is positively regulated in a COI1- and MYC2-dependent manner in Arabidopsis (Arabidopsis thaliana). However, contrary to myc2, the jam1jam2jam3 triple mutant exhibited shorter roots when treated with methyl jasmonate (MJ), indicating enhanced responsiveness to JA. Our genome-wide expression analyses revealed that key jasmonate metabolic genes as well as a set of genes encoding transcription factors that regulate the JA-responsive metabolic genes are negatively regulated by JAMs after MJ treatment. Consistently, loss of JAM genes resulted in higher accumulation of anthocyanin in MJ-treated plants as well as higher accumulation of JA and 12-hydroxyjasmonic acid in wounded plants. These results show that JAMs negatively regulate the JA responses in a manner that is mostly antagonistic to MYC2.

  7. Dynamics of Jasmonate Metabolism upon Flowering and across Leaf Stress Responses in Arabidopsis thaliana.

    PubMed

    Widemann, Emilie; Smirnova, Ekaterina; Aubert, Yann; Miesch, Laurence; Heitz, Thierry

    2016-01-06

    The jasmonic acid (JA) signaling pathway plays important roles in adaptation of plants to environmental cues and in specific steps of their development, particularly in reproduction. Recent advances in metabolic studies have highlighted intricate mechanisms that govern enzymatic conversions within the jasmonate family. Here we analyzed jasmonate profile changes upon Arabidopsis thaliana flower development and investigated the contribution of catabolic pathways that were known to turnover the active hormonal compound jasmonoyl-isoleucine (JA-Ile) upon leaf stress. We report a rapid decline of JA-Ile upon flower opening, concomitant with the massive accumulation of its most oxidized catabolite, 12COOH-JA-Ile. Detailed genetic analysis identified CYP94C1 as the major player in this process. CYP94C1 is one out of three characterized cytochrome P450 enzymes that define an oxidative JA-Ile turnover pathway, besides a second, hydrolytic pathway represented by the amido-hydrolases IAR3 and ILL6. Expression studies combined with reporter gene analysis revealed the dominant expression of CYP94C1 in mature anthers, consistent with the established role of JA signaling in male fertility. Significant CYP94B1 expression was also evidenced in stamen filaments, but surprisingly, CYP94B1 deficiency was not associated with significant changes in JA profiles. Finally, we compared global flower JA profiles with those previously reported in leaves reacting to mechanical wounding or submitted to infection by the necrotrophic fungus Botrytis cinerea. These comparisons revealed distinct dynamics of JA accumulation and conversions in these three biological systems. Leaf injury boosts a strong and transient JA and JA-Ile accumulation that evolves rapidly into a profile dominated by ω-oxidized and/or Ile-conjugated derivatives. In contrast, B. cinerea-infected leaves contain mostly unconjugated jasmonates, about half of this content being ω-oxidized. Finally, developing flowers present an

  8. Dynamics of Jasmonate Metabolism upon Flowering and across Leaf Stress Responses in Arabidopsis thaliana

    PubMed Central

    Widemann, Emilie; Smirnova, Ekaterina; Aubert, Yann; Miesch, Laurence; Heitz, Thierry

    2016-01-01

    The jasmonic acid (JA) signaling pathway plays important roles in adaptation of plants to environmental cues and in specific steps of their development, particularly in reproduction. Recent advances in metabolic studies have highlighted intricate mechanisms that govern enzymatic conversions within the jasmonate family. Here we analyzed jasmonate profile changes upon Arabidopsis thaliana flower development and investigated the contribution of catabolic pathways that were known to turnover the active hormonal compound jasmonoyl-isoleucine (JA-Ile) upon leaf stress. We report a rapid decline of JA-Ile upon flower opening, concomitant with the massive accumulation of its most oxidized catabolite, 12COOH-JA-Ile. Detailed genetic analysis identified CYP94C1 as the major player in this process. CYP94C1 is one out of three characterized cytochrome P450 enzymes that define an oxidative JA-Ile turnover pathway, besides a second, hydrolytic pathway represented by the amido-hydrolases IAR3 and ILL6. Expression studies combined with reporter gene analysis revealed the dominant expression of CYP94C1 in mature anthers, consistent with the established role of JA signaling in male fertility. Significant CYP94B1 expression was also evidenced in stamen filaments, but surprisingly, CYP94B1 deficiency was not associated with significant changes in JA profiles. Finally, we compared global flower JA profiles with those previously reported in leaves reacting to mechanical wounding or submitted to infection by the necrotrophic fungus Botrytis cinerea. These comparisons revealed distinct dynamics of JA accumulation and conversions in these three biological systems. Leaf injury boosts a strong and transient JA and JA-Ile accumulation that evolves rapidly into a profile dominated by ω-oxidized and/or Ile-conjugated derivatives. In contrast, B. cinerea-infected leaves contain mostly unconjugated jasmonates, about half of this content being ω-oxidized. Finally, developing flowers present an

  9. The Role of the Jasmonate Response in Plant Susceptibility to Diverse Pathogens with a Range of Lifestyles1[w

    PubMed Central

    Thaler, Jennifer S.; Owen, Blythe; Higgins, Verna J.

    2004-01-01

    Plants defend themselves against attack from insects and pathogens with various resistance strategies. The jasmonate and salicylate signaling pathways are two induced responses that protect plants against these attackers. Knowledge of the range of organisms that are affected by each response is important for understanding how plants coordinate their defenses against multiple attackers and the generality of effect of different resistance mechanisms. The jasmonate response is known to protect plants against a wide range of insect herbivores; in this study, we examined the role of the jasmonate response in susceptibility to eight pathogens with diverse lifestyles in the laboratory and field. Recent biochemical models suggest that the lifestyle of the pathogen (necrotroph versus biotroph) should predict whether the jasmonate response will be involved in resistance. We tested this by examining the susceptibility of wild-type (cv Castlemart with no known genes for resistance to the pathogens used) and jasmonate-deficient mutant tomato (Lycopersicon esculentum) plants (def1) and by employing rescue treatments of the mutant. Plant susceptibility to five of the eight pathogens we examined was reduced by the jasmonate response, including two bacteria (Pseudomonas syringae and Xanthomonas campestris), two fungi (Verticillium dahliae and Fusarium oxysporum f. sp. lycopersici), and an oomycete (Phytophthora infestans). Susceptibility to three fungi was unaffected (Cladosporium fulvum, Oidium neolycopersici, and Septoria lycopersici). Our results indicate that the jasmonate response reduces damage by a wide range of pathogens from different lifestyles, a result that contrasts with the emerging picture of diseases on Arabidopsis. Thus, the generality of jasmonate-based resistance of tomato challenges the view that ecologically distinct plant parasites are resisted via different mechanisms. PMID:15133157

  10. Jasmonate-dependent and -independent pathways mediate specific effects of solar ultraviolet B radiation on leaf phenolics and antiherbivore defense.

    PubMed

    Demkura, Patricia V; Abdala, Guillermina; Baldwin, Ian T; Ballaré, Carlos L

    2010-02-01

    Ultraviolet B (UV-B) radiation, a very small fraction of the daylight spectrum, elicits changes in plant secondary metabolism that have large effects on plant-insect interactions. The signal transduction pathways that mediate these specific effects of solar UV-B are not known. We examined the role of jasmonate signaling by measuring responses to UV-B in wild-type and transgenic jasmonate-deficient Nicotiana attenuata plants in which a lipoxygenase gene (NaLOX3) was silenced (as-lox). In wild-type plants, UV-B failed to elicit the accumulation of jasmonic acid (JA) or the bioactive JA-isoleucine conjugate but amplified the response of jasmonate-inducible genes, such as trypsin proteinase inhibitor (TPI), to wounding and methyl jasmonate, and increased the accumulation of several phenylpropanoid derivatives. Some of these phenolic responses (accumulation of caffeoyl-polyamine conjugates) were completely lacking in as-lox plants, whereas others (accumulation of rutin and chlorogenic acid) were similar in both genotypes. In open field conditions, as-lox plants received more insect damage than wild-type plants, as expected, but the dramatic increase in resistance to herbivory elicited by UV-B exposure, which was highly significant in wild-type plants, did not occur in as-lox plants. We conclude that solar UV-B (1) uses jasmonate-dependent and -independent pathways in the elicitation of phenolic compounds, and (2) increases sensitivity to jasmonates, leading to enhanced expression of wound-response genes (TPI). The lack of UV-B-induced antiherbivore protection in as-lox plants suggests that jasmonate signaling plays a central role in the mechanisms by which solar UV-B increases resistance to insect herbivores in the field.

  11. Enhanced daidzin production from jasmonic and acetyl salicylic acid elicited hairy root cultures of Psoralea corylifolia L. (Fabaceae).

    PubMed

    Zaheer, Mohd; Reddy, Vudem Dashavantha; Giri, Charu Chandra

    2016-07-01

    Daidzin (7-O-glucoside of daidzein) has several pharmacological benefits in herbal remedy, as antioxidant and shown antidipsotropic activity. Hairy root culture of Psoralea corylifolia L. was developed for biomass and enhanced daidzin production using signalling compounds such as jasmonic acid (JA) and acetyl salicylic acid (ASA). Best response of 2.8-fold daidzin (5.09% DW) with 1 μM JA treatment after second week and 7.3-fold (3.43% DW) with 10 μM JA elicitation after 10th week was obtained from hairy roots compared to untreated control. ASA at 10 μM promoted 1.7-fold increase in daidzin (1.49% DW) content after seventh week compared to control (0.83% DW). Addition of 25 μM ASA resulted in 1.44% DW daidzin (1.5-fold increase) with 0.91% DW in control after fifth week and 1.44% DW daidzin (2.3-fold increase) after eighth week when compared to untreated control (0.62% DW). Reduced biomass with increased daidzin content was facilitated by elicited hairy root cultures.

  12. Late results.

    PubMed

    Daly, B D

    1999-08-01

    Pneumonectomy is performed for a number of benign and malignant conditions. It is most commonly performed for lung cancer. Adjuvant and neoadjuvant protocols have increased the number of these operations being performed and the long-term results are improving. Pneumonectomy may also be performed for metastases to lung and for mesothelioma with encouraging results. Some bronchial adenomas require pneumonectomy. Treatment of resistant mycobacteria or the complications of tuberculosis frequently require pneumonectomy. Late bronchopleural fistulae, esophagopleural fistulae, and empyema may occur.

  13. Association of maternal serum homocysteine concentration levels in late stage of pregnancy with preterm births: a nested case-control study.

    PubMed

    Qiu, Xiantao; Gao, Fei; Qiu, Yuanyuan; Bao, Junjie; Gu, Xiaoqiong; Long, Yan; Liu, Fei; Cai, Minmin; Liu, Haiying

    2017-08-11

    To investigate the relationship between maternal serum homocysteine (Hcy) levels in the late stage of pregnancy and preterm birth. Other relevant biochemical parameters were measured to establish the normal reference interval of serum Hcy in both women in the late stage of pregnancy and neonates. The nested case-control study included 300 singleton pregnant women with preterm births between June 2013 and May 2015 and their premature delivered babies as a preterm group. Blood sample within three days before delivery was collected. Simultaneously, 300 healthy pregnant women admitted during the same time, and singleton mature neonates who had gestational week-matched blood sample were age-matched as a control group. Maternal serum levels of Hcy, total triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), uric acid (UA), free fatty acids (FAA) and superoxide dismutase (SOD) were all higher in the preterm group than in the control group except high-density lipoprotein cholesterol (HDL-C). Serum levels of Hcy, TC, LDL-C, UA, FAA and SOD were higher in prematurely delivered neonates than in the control group except for HDL-C. The body weight of prematurely delivered neonates was negatively correlated with the maternal serum levels of Hcy and UA before delivery. Higher maternal serum Hcy levels were associated with preterm birth and neonatal body weight. Elevated maternal serum levels of Hcy might serve as a biomarker for preterm birth prediction.

  14. Isolation of the four methyl jasmonate stereoisomers and their effects on selected chiral volatile compounds in red raspberries.

    PubMed

    Flores, Gema; Blanch, Gracia Patricia; Ruiz del Castillo, Maria Luisa

    2013-12-01

    The four stereoisomers present in a commercial sample of methyl jasmonate (MJ) were isolated at semi-preparative scale by HPLC, using a permethylated β-cyclodextrin column. This allowed the baseline resolution and collection of both major (methyl jasmonates) and minor (epi-methyl jasmonates) stereoisomers. When 1.5 mL of a 5mg per mL MJ solution were injected, isolated amounts were 3.56 mg for (-) and (+)-methyl jasmonates, with respective purities of 96.1% and 99.9%, and 0.18 mg for (-)- and (+)-epi-methyl jasmonates, with 98.6% and 91.6% respective purities. The post-harvest treatment of red raspberry fruits with the pure methyl jasmonate stereoisomers isolated proved that (-)-epi-MJ either promotes the bioformation of (+)-limonene or inhibits that of (-)-limonene to a greater extent than the other three MJ stereoisomers, while the biosynthesis of the (+)-enantiomer of α-ionone is favoured equally, whichever MJ stereoisomer used. The results obtained in the present study might be used to obtain food products with improved sensory characteristics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Applying generalized additive models to unravel dynamic changes in anthocyanin biosynthesis in methyl jasmonate elicited grapevine (Vitis vinifera cv. Gamay) cell cultures

    PubMed Central

    Saw, Nay Min Min Thaw; Moser, Claudio; Martens, Stefan; Franceschi, Pietro

    2017-01-01

    Plant cell cultures represent important model systems to understand metabolism and its modulation by regulatory factors. Even in controlled conditions, cell metabolism is highly dynamic and can be fully characterized only by time course experiments. Here, we show that statistical analysis of this type of data gains power if it moves to approaches able to compare the ‘trends’ of the different metabolites. In particular, we show how generalized additive models can be used to model the time-dependent profile of anthocyanin synthesis in grapevine cell suspension cultures (Vitis vinifera cv. Gamay), following treatment with 100 μm methyl jasmonate. The sampling was performed daily for 20 days of culturing following elicitation at day 5. All samples were analyzed by UPLC-MS/MS for the identification and quantification of fifteen anthocyanin compounds. The models confirmed the separation in the anthocyanin biosynthetic pathway between delphinidin-based and cyanidin-based compounds, showing that methyl jasmonate modulates the anthocyanin concentration profiles. Our results clearly indicate that the combination of high-throughput metabolomics and state of the art statistical modeling is a powerful approach to study plant metabolism. This approach is expected to gain popularity due to the growing availability of low-cost high-throughput ‘omic’ assays. PMID:28758015

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

    PubMed

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

    1999-11-01

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

  17. Late vs early clamping of the umbilical cord in full-term neonates: systematic review and meta-analysis of controlled trials.

    PubMed

    Hutton, Eileen K; Hassan, Eman S

    2007-03-21

    With few exceptions, the umbilical cord of every newborn is clamped and cut at birth, yet the optimal timing for this intervention remains controversial. To compare the potential benefits and harms of late vs early cord clamping in term infants. Search of 6 electronic databases (on November 15, 2006, starting from the beginning of each): the Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Neonatal Group trials register, the Cochrane library, MEDLINE, EMBASE, and CINHAL; hand search of secondary references in relevant studies; and contact of investigators about relevant published research. Controlled trials comparing late vs early cord clamping following birth in infants born at 37 or more weeks' gestation. Two reviewers independently assessed eligibility and quality of trials and extracted data for outcomes of interest: infant hematologic status; iron status; and risk of adverse events such as jaundice, polycythemia, and respiratory distress. The meta-analysis included 15 controlled trials (1912 newborns). Late cord clamping was delayed for at least 2 minutes (n = 1001 newborns), while early clamping in most trials (n = 911 newborns) was performed immediately after birth. Benefits over ages 2 to 6 months associated with late cord clamping include improved hematologic status measured as hematocrit (weighted mean difference [WMD], 3.70%; 95% confidence interval [CI], 2.00%-5.40%); iron status as measured by ferritin concentration (WMD, 17.89; 95% CI, 16.58-19.21) and stored iron (WMD, 19.90; 95% CI, 7.67-32.13); and a clinically important reduction in the risk of anemia (relative risk (RR), 0.53; 95% CI, 0.40-0.70). Neonates with late clamping were at increased risk of experiencing asymptomatic polycythemia (7 studies [403 neonates]: RR, 3.82; 95% CI, 1.11-13.21; 2 high-quality studies only [281 infants]: RR, 3.91; 95% CI, 1.00-15.36). Delaying clamping of the umbilical cord in full-term neonates for a minimum of 2 minutes following birth is

  18. Effects of jasmonic acid signalling on the wheat microbiome differ between body sites

    PubMed Central

    Liu, Hongwei; Carvalhais, Lilia C.; Schenk, Peer M.; Dennis, Paul G.

    2017-01-01

    Jasmonic acid (JA) signalling helps plants to defend themselves against necrotrophic pathogens and herbivorous insects and has been shown to influence the root microbiome of Arabidopsis thaliana. In this study, we determined whether JA signalling influences the diversity and functioning of the wheat (Triticum aestivum) microbiome and whether these effects are specific to particular parts of the plant. Activation of the JA pathway was achieved via exogenous application of methyl jasmonate and was confirmed by significant increases in the abundance of 10 JA-signalling-related gene transcripts. Phylogenetic marker gene sequencing revealed that JA signalling reduced the diversity and changed the composition of root endophytic but not shoot endophytic or rhizosphere bacterial communities. The total enzymatic activity and substrate utilisation profiles of rhizosphere bacterial communities were not affected by JA signalling. Our findings indicate that the effects of JA signalling on the wheat microbiome are specific to individual plant compartments. PMID:28134326

  19. Endogenous Bioactive Jasmonate Is Composed of a Set of (+)-7-iso-JA-Amino Acid Conjugates.

    PubMed

    Yan, Jianbin; Li, Suhua; Gu, Min; Yao, Ruifeng; Li, Yuwen; Chen, Juan; Yang, Mai; Tong, Jianhua; Xiao, Langtao; Nan, Fajun; Xie, Daoxin

    2016-12-01

    Jasmonates (JAs) regulate a wide range of plant defense and development processes. The bioactive JA is perceived by its receptor COI1 to trigger the degradation of JASMONATE ZIM-DOMAIN (JAZ) proteins and subsequently derepress the JAZ-repressed transcription factors for activation of expression of JA-responsive genes. So far, (+)-7-iso-JA-l-Ile has been the only identified endogenous bioactive JA molecule. Here, we designed coronafacic acid (CFA) conjugates with all the amino acids (CFA-AA) to mimic the JA amino acid conjugates, and revealed that (+)-7-iso-JA-Leu, (+)-7-iso-JA-Val, (+)-7-iso-JA-Met, and (+)-7-iso-JA-Ala are new endogenous bioactive JA molecules. Furthermore, our studies uncover the general characteristics for all the bioactive JA molecules, and provide a new strategy to synthetically generate novel active JA molecules.

  20. A case-control study to examine the association between breastfeeding during late pregnancy and risk of a small-for-gestational-age birth in Lima, Peru.

    PubMed

    Pareja, Rossina G; Marquis, Grace S; Penny, Mary E; Dixon, Philip M

    2015-04-01

    Excessive demands on maternal nutritional status may be a risk factor for poor birth outcomes. This study examined the association between breastfeeding during late pregnancy (≥ 28 weeks) and the risk of having a small-for-gestational-age (SGA) newborn, using a matched case-control design (78 SGA cases: birthweight <10th percentile for gestational age; 150 non-SGA controls: 50th percentile controls based on hospital, gestational age, and inter-gestational period. Mothers were interviewed and clinical chart extractions were completed. Factors associated with risk of SGA were assessed by their adjusted odds ratios (aOR) from conditional logistic regression. Exposure to an overlap of breastfeeding during late pregnancy was not associated with an increased risk of having a SGA newborn [aOR=0.58, 95% confidence interval (CI): 0.10-3.30]. However, increased risk was associated with having a previous low-birthweight birth (aOR=6.53; 95% CI: 1.43-29.70) and a low intake of animal source foods (<25th percentile; aOR=2.26; 95% CI: 1.01-5.04), and tended to be associated with being short (<150 cm; aOR=2.05; 95% CI: 0.92-4.54). This study found no evidence to support the hypothesis that breastfeeding during late pregnancy increases the risk for SGA; however, studies with greater statistical power are needed to definitively examine this possible association and clarify whether there are other risks to the new baby, the toddler and the pregnant woman. © 2012 Blackwell Publishing Ltd.

  1. Regulation of isoflavone production in hydroponically grown Pueraria montana (kudzu) by cork pieces, XAD-4, and methyl jasmonate.

    PubMed

    Kirakosyan, Ara; Kaufman, Peter B; Chang, Soo Chul; Warber, Sara; Bolling, Steven; Vardapetyan, Hrachik

    2006-12-01

    A mini-hydroponic growing system was employed for seedlings of kudzu vine (Pueraria montana) and contents of isoflavones (daidzein, genistein, daidzin, genistin, and puerarin) from shoot and root parts of seedlings were analyzed quantitatively. In addition, exogenous cork pieces, polymeric adsorbent, XAD-4, and universal elicitor, methyl jasmonate (MeJA), were used to regulate the production of these isoflavones. It was shown that cork pieces up-regulate the production of daidzein and genistein up to seven- and eight-fold greater than the levels obtained for control roots. In contrast, levels of glucosyl conjugates, daidzin and genistin, decrease up to five- and eight-fold, respectively. Cork treatment also induces the excretion of the root isoflavone constituents into the growth medium. Minimal levels of isoflavones are absorbed by the cork pieces. XAD-4 stimulates the production of glucosyl conjugates, daidzin and genistin, in root parts about 1.5-fold greater than that obtained in control roots. These are the highest amounts of daidzin and genistin that are observed (5.101 and 6.759 mg g(-1) dry weight, respectively). In contrast to these two adsorbents, MeJA increases the accumulation of isoflavones in shoot rather than in root parts of seedlings, about three- to four-fold over control levels, with the exception of genistein. These studies reveal new observations on the regulation of isoflavone production in hydroponically grown Pueraria montana plants by two adsorbents (cork pieces and XAD-4) and MeJA elicitor.

  2. Occurrence of jasmonates during cystocarp development in the red alga Grateloupia imbricata.

    PubMed

    Pilar, Garcia-Jimenez; Olegario, Brito-Romano; Rafael, Robaina R

    2016-12-01

    In this study, we highlight the effects of methyl jasmonate (MeJa) on cystocarp development in the red macroscopic alga Grateloupia imbricata. In G. imbricata, jasmonate release is related to the reproductive state, as fertile thalli (i.e., those that have cystocarps) released significant amounts of this volatile compound (1.27 ± 0.20 mM · mg fw(-1)  · h(-1) ) compared