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Sample records for acid stress response

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

    Carolina Salazar

    2015-08-01

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

  2. Physiological responses of Daphnia pulex to acid stress

    Pirow Ralph; Weber Anna K

    2009-01-01

    Abstract Background Acidity exerts a determining influence on the composition and diversity of freshwater faunas. While the physiological implications of freshwater acidification have been intensively studied in teleost fish and crayfish, much less is known about the acid-stress physiology of ecologically important groups such as cladoceran zooplankton. This study analyzed the extracellular acid-base state and CO2 partial pressure (PCO2), circulation and ventilation, as well as the respiratio...

  3. Physiological responses of Daphnia pulex to acid stress

    Pirow Ralph

    2009-04-01

    Full Text Available Abstract Background Acidity exerts a determining influence on the composition and diversity of freshwater faunas. While the physiological implications of freshwater acidification have been intensively studied in teleost fish and crayfish, much less is known about the acid-stress physiology of ecologically important groups such as cladoceran zooplankton. This study analyzed the extracellular acid-base state and CO2 partial pressure (PCO2, circulation and ventilation, as well as the respiration rate of Daphnia pulex acclimated to acidic (pH 5.5 and 6.0 and circumneutral (pH 7.8 conditions. Results D. pulex had a remarkably high extracellular pH of 8.33 and extracellular PCO2 of 0.56 kPa under normal ambient conditions (pH 7.8 and normocapnia. The hemolymph had a high bicarbonate concentration of 20.9 mM and a total buffer value of 51.5 meq L-1 pH-1. Bicarbonate covered 93% of the total buffer value. Acidic conditions induced a slight acidosis (ΔpH = 0.16–0.23, a 30–65% bicarbonate loss, and elevated systemic activities (tachycardia, hyperventilation, hypermetabolism. pH 6.0 animals partly compensated the bicarbonate loss by increasing the non-bicarbonate buffer value from 2.0 to 5.1 meq L-1 pH-1. The extracellular PCO2 of pH 5.5 animals was significantly reduced to 0.33 kPa, and these animals showed the highest tolerance to a short-term exposure to severe acid stress. Conclusion Chronic exposure to acidic conditions had a pervasive impact on Daphnia's physiology including acid-base balance, extracellular PCO2, circulation and ventilation, and energy metabolism. Compensatory changes in extracellular non-bicarbonate buffering capacity and the improved tolerance to severe acid stress indicated the activation of defense mechanisms which may result from gene-expression mediated adjustments in hemolymph buffer proteins and in epithelial properties. Mechanistic analyses of the interdependence between extracellular acid-base balance and CO2 transport

  4. Glutathione is involved in physiological response of Candida utilis to acid stress.

    Wang, Da-Hui; Zhang, Jun-Li; Dong, Ying-Ying; Wei, Gong-Yuan; Qi, Bin

    2015-12-01

    Candida utilis often encounters an acid stress environment when hexose and pentose are metabolized to produce acidic bio-based materials. In order to reveal the physiological role of glutathione (GSH) in the response of cells of this industrial yeast to acid stress, an efficient GSH-producing strain of C. utilis CCTCC M 209298 and its mutants deficient in GSH biosynthesis, C. utilis Δgsh1 and Δgsh2, were used in this study. A long-term mild acid challenge (pH 3.5 for 6 h) and a short-term severe acid challenge (pH 1.5 for 2 h) were conducted at 18 h during batch culture of the yeast to generate acid stress conditions. Differences in the physiological performances among the three strains under acid stress were analyzed in terms of GSH biosynthesis and distribution; intracellular pH; activities of γ-glutamylcysteine synthetase, catalase, and superoxide dismutase; intracellular ATP level; and ATP/ADP ratio. The intracellular GSH content of the yeast was found to be correlated with changes in physiological data, and a higher intracellular GSH content led to greater relief of cells to the acid stress, suggesting that GSH may be involved in protecting C. utilis against acid stress. Results presented in this manuscript not only increase our understanding of the impact of GSH on the physiology of C. utilis but also help us to comprehend the mechanism underlying the response to acid stress of eukaryotic microorganisms. PMID:26346268

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

    Yucheng Wang

    2013-05-01

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

  6. Docosahexaenoic Acid Ameliorates Fructose-Induced Hepatic Steatosis Involving ER Stress Response in Primary Mouse Hepatocytes

    Jinying Zheng; Chuan Peng; Yanbiao Ai; Heng Wang; Xiaoqiu Xiao; Jibin Li

    2016-01-01

    The increase in fructose consumption is considered to be a risk factor for developing nonalcoholic fatty liver disease (NAFLD). We investigated the effects of docosahexaenoic acid (DHA) on hepatic lipid metabolism in fructose-treated primary mouse hepatocytes, and the changes of Endoplasmic reticulum (ER) stress pathways in response to DHA treatment. The hepatocytes were treated with fructose, DHA, fructose plus DHA, tunicamycin (TM) or fructose plus 4-phenylbutyric acid (PBA) for 24 h. Intra...

  7. Molecular mechanisms of Saccharomyces cerevisiae stress adaptation and programmed cell death in response to acetic acid

    Sergio eGiannattasio

    2013-02-01

    Full Text Available Beyond its classical biotechnological applications such as food and beverage production or as a cell factory, the yeast Saccharomyces cerevisiae is a valuable model organism to study fundamental mechanisms of cell response to stressful environmental changes. Acetic acid is a physiological product of yeast fermentation and it is a well-known food preservative due to its antimicrobial action. Acetic acid has recently been shown to cause yeast cell death and aging. Here we shall focus on the molecular mechanisms of S. cerevisiae stress adaptation and programmed cell death in response to acetic acid. We shall elaborate on the intracellular signaling pathways involved in the cross-talk of pro-survival and pro-death pathways underlying the importance of understanding fundamental aspects of yeast cell homeostasis to improve the performance of a given yeast strain in biotechnological applications.

  8. Water stress responses of tomato mutants impaired in hormone biosynthesis reveal abscisic acid, jasmonic acid and salicylic acid interactions

    Valeria eMuñoz

    2015-11-01

    Full Text Available To investigate the putative crosstalk between JA and ABA in Solanum lycopersicum plants in response to drought, suppressor of prosystemin-mediated responses2 (spr2, JA-deficient and flacca (flc, ABA-deficient mutants together with the naphthalene/salicylate hydroxylase (NahG transgenic (SA-deficient line were used. Hormone profiling and gene expression of key enzymes in ABA, JA and SA biosynthesis were analyzed during early stages of drought. ABA accumulation was comparable in spr2 and wild type (WT plants whereas expression of 9-cis-epoxycarotenoid dioxygenase 1 (NCED1 and NCED2 was different, implying a compensation mechanism between NCED genes and an organ-specific regulation of NCED1 expression. JA levels and 12-oxo-phytodienoic acid reductase 3 (OPR3 expression in flc plants suggest that ABA regulates the induction of the OPR3 gene in roots. By contrast, ABA treatment to flc plants leads to a reduction of JA and SA contents. Furthermore, different pattern of SA accumulation (and expression of isochorismate synthase and phenylalanine ammonia lyase 1 was observed between WT seedlings and mutants, suggesting that SA plays an important role on the early response of tomato plants to drought and also that JA and ABA modulate its biosynthesis. Finally, hormone profiling in spr2 and NahG plants indicate a crosstalk between JA and SA that could enhance tolerance of tomato to water stress.

  9. Water Stress Responses of Tomato Mutants Impaired in Hormone Biosynthesis Reveal Abscisic Acid, Jasmonic Acid and Salicylic Acid Interactions.

    Muñoz-Espinoza, Valeria A; López-Climent, María F; Casaretto, José A; Gómez-Cadenas, Aurelio

    2015-01-01

    To investigate the putative crosstalk between JA and ABA in Solanum lycopersicum plants in response to drought, suppressor of prosystemin-mediated responses2 (spr2, JA-deficient) and flacca (flc, ABA-deficient) mutants together with the naphthalene/salicylate hydroxylase (NahG) transgenic (SA-deficient) line were used. Hormone profiling and gene expression of key enzymes in ABA, JA and SA biosynthesis were analyzed during early stages of drought. ABA accumulation was comparable in spr2 and wild type (WT) plants whereas expression of 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and NCED2 was different, implying a compensation mechanism between NCED genes and an organ-specific regulation of NCED1 expression. JA levels and 12-oxo-phytodienoic acid reductase 3 (OPR3) expression in flc plants suggest that ABA regulates the induction of the OPR3 gene in roots. By contrast, ABA treatment to flc plants leads to a reduction of JA and SA contents. Furthermore, different pattern of SA accumulation (and expression of isochorismate synthase and phenylalanine ammonia lyase 1) was observed between WT seedlings and mutants, suggesting that SA plays an important role on the early response of tomato plants to drought and also that JA and ABA modulate its biosynthesis. Finally, hormone profiling in spr2 and NahG plants indicate a crosstalk between JA and SA that could enhance tolerance of tomato to water stress. PMID:26635826

  10. Functional annotation of the transcriptome of Sorghum bicolor in response to osmotic stress and abscisic acid

    Kumari Sunita

    2011-10-01

    Full Text Available Abstract Background Higher plants exhibit remarkable phenotypic plasticity allowing them to adapt to an extensive range of environmental conditions. Sorghum is a cereal crop that exhibits exceptional tolerance to adverse conditions, in particular, water-limiting environments. This study utilized next generation sequencing (NGS technology to examine the transcriptome of sorghum plants challenged with osmotic stress and exogenous abscisic acid (ABA in order to elucidate genes and gene networks that contribute to sorghum's tolerance to water-limiting environments with a long-term aim of developing strategies to improve plant productivity under drought. Results RNA-Seq results revealed transcriptional activity of 28,335 unique genes from sorghum root and shoot tissues subjected to polyethylene glycol (PEG-induced osmotic stress or exogenous ABA. Differential gene expression analyses in response to osmotic stress and ABA revealed a strong interplay among various metabolic pathways including abscisic acid and 13-lipoxygenase, salicylic acid, jasmonic acid, and plant defense pathways. Transcription factor analysis indicated that groups of genes may be co-regulated by similar regulatory sequences to which the expressed transcription factors bind. We successfully exploited the data presented here in conjunction with published transcriptome analyses for rice, maize, and Arabidopsis to discover more than 50 differentially expressed, drought-responsive gene orthologs for which no function had been previously ascribed. Conclusions The present study provides an initial assemblage of sorghum genes and gene networks regulated by osmotic stress and hormonal treatment. We are providing an RNA-Seq data set and an initial collection of transcription factors, which offer a preliminary look into the cascade of global gene expression patterns that arise in a drought tolerant crop subjected to abiotic stress. These resources will allow scientists to query gene

  11. Docosahexaenoic Acid Ameliorates Fructose-Induced Hepatic Steatosis Involving ER Stress Response in Primary Mouse Hepatocytes

    Jinying Zheng

    2016-01-01

    Full Text Available The increase in fructose consumption is considered to be a risk factor for developing nonalcoholic fatty liver disease (NAFLD. We investigated the effects of docosahexaenoic acid (DHA on hepatic lipid metabolism in fructose-treated primary mouse hepatocytes, and the changes of Endoplasmic reticulum (ER stress pathways in response to DHA treatment. The hepatocytes were treated with fructose, DHA, fructose plus DHA, tunicamycin (TM or fructose plus 4-phenylbutyric acid (PBA for 24 h. Intracellular triglyceride (TG accumulation was assessed by Oil Red O staining. The mRNA expression levels and protein levels related to lipid metabolism and ER stress response were determined by real-time PCR and Western blot. Fructose treatment led to obvious TG accumulation in primary hepatocytes through increasing expression of fatty acid synthase (FAS and acetyl-CoA carboxylase (ACC, two key enzymes in hepatic de novo lipogenesis. DHA ameliorates fructose-induced TG accumulation by upregulating the expression of carnitine palmitoyltransferase 1A (CPT-1α and acyl-CoA oxidase 1 (ACOX1. DHA treatment or pretreatment with the ER stress inhibitor PBA significantly decreased TG accumulation and reduced the expression of glucose-regulated protein 78 (GRP78, total inositol-requiring kinase 1 (IRE1α and p-IRE1α. The present results suggest that DHA protects against high fructose-induced hepatocellular lipid accumulation. The current findings also suggest that alleviating the ER stress response seems to play a role in the prevention of fructose-induced hepatic steatosis by DHA.

  12. RESPONSE OF SPECKLED SPUR-FLOWER TO SALINITY STRESS AND SALICYLIC ACID TREATMENT

    Piotr Salachna

    2015-11-01

    Full Text Available One of the limitations to using ornamental plants in green areas is too high salinity and alkalization of the soil. The adverse effect of salinity on plant growth and development may be effectively reduced by application of salicylic acid. Plectranthus ciliatus is an attractive bed plant with ornamental leaves, recommended for growing in containers, hanging baskets, or sunny borders. The aim of this study was to investigate the response of P. ciliatus to salicylic acid and calcium chloride. The plants were grown in pots in a glasshouse and were sprayed with solution of 0.5 mM salicylic acid and watered with 200 mM calcium chloride. The application of salicylic acid resulted in an increased weight of the aboveground parts, higher stomatal conductance and leaf greenness index and enhanced leaf content of nitrogen, potassium, iron and zinc. Salinity-exposed plants were characterized by reduced weight, stomatal conductance and leaf greenness index. Salt stress caused also a drop in leaf content of nitrogen, potassium and iron, and an increase in calcium, sodium, chlorine, copper and manganese concentration. Salicylic acid seemed to relieve salinity-mediated plant stress.

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

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

  14. Gene-related strain variation of Staphylococcus aureus for homologous resistance response to acid stress.

    Lee, Soomin; Ahn, Sooyeon; Lee, Heeyoung; Kim, Won-Il; Kim, Hwang-Yong; Ryu, Jae-Gee; Kim, Se-Ri; Choi, Kyoung-Hee; Yoon, Yohan

    2014-10-01

    This study investigated the effect of adaptation of Staphylococcus aureus strains to the acidic condition of tomato in response to environmental stresses, such as heat and acid. S. aureus ATCC 13565, ATCC 14458, ATCC 23235, ATCC 27664, and NCCP10826 habituated in tomato extract at 35°C for 24 h were inoculated in tryptic soy broth. The culture suspensions were then subjected to heat challenge or acid challenge at 60°C and pH 3.0, respectively, for 60 min. In addition, transcriptional analysis using quantitative real-time PCR was performed to evaluate the expression level of acid-shock genes, such as clpB, zwf, nuoF, and gnd, from five S. aureus strains after the acid habituation of strains in tomato at 35°C for 15 min and 60 min in comparison with that of the nonhabituated strains. In comparison with the nonhabituated strains, the five tomato-habituated S. aureus strains did not show cross protection to heat, but tomato-habituated S. aureus ATCC 23235 showed acid resistance. In quantitative real-time-PCR analysis, the relative expression levels of acid-shock genes (clpB, zwf, nuoF, and gnd) were increased the most in S. aureus ATCC 23235 after 60 min of tomato habituation, but there was little difference in the expression levels among the five S. aureus strains after 15 min of tomato habituation. These results indicate that the variation of acid resistance of S. aureus is related to the expression of acid-shock genes during acid habituation. PMID:25285500

  15. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    Collado, Sergio; Rosas, Irene; González, Elena; Gutierrez-Lavin, Antonio; Diaz, Mario, E-mail: mariodiaz@uniovi.es

    2014-02-01

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h{sup −1} and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum Y{sub X/S} of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m{sup 2}.

  16. Pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions

    Highlights: • MBR under feed-induced stress conditions: starvation and changing feeding conditions. • High capacity of MBR to withstand high variations in feed loads. • Slow biofilm formation under starvation conditions during the first days. • Observed growth of P. putida for substrate to microorganism ratio higher than 0.6 g/g. • Maximum specific growth rate and growth yield values of around 37.5 h−1 and 0.5 g/g. - Abstract: Starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. They are typical causes of unsteady-state operation of biological systems and provoke cellular stress. The response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. In order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of Pseudomonas putida was selected instead of an activated sludge and a sole substrate (salicylic acid) was employed. The system degraded salicylic acid at 100–1100 mg/L with a high level of efficiency, showed rapid acclimation without substrate or product inhibition phenomena and good stability in response to unsteady states caused by feed variations. Under starvation conditions, specific degradation rates of around 15 mg/g h were achieved during the adaptation of the biomass to the new conditions and no biofilm formation was observed during the first days of experimentation using an initial substrate to microorganisms ratio lower than 0.1. When substrate was added to the reactor as pulses resulting in rapidly changing concentrations, P. putida growth was observed only for substrate to microorganism ratios higher than 0.6, with a maximum YX/S of 0.5 g/g. Biofilm development under changing feeding conditions was fast, biomass detachment only being significant for biomass concentrations on the membrane surface that were higher than 16 g/m2

  17. Stress response of some lactic acid bacteria isolated from Romanian artisan dairy products.

    Zamfir, Medana; Grosu-Tudor, Silvia-Simona

    2014-02-01

    Understanding the mechanisms of stress response and adaptation to stress in the case of lactic acid bacteria (LAB), especially in the case of strains with functional properties, is very important when such strains are potential candidates for starter cultures or probiotics. In this context, our study shows the response of some LAB [four exopolysaccharide (EPS)-producing strains and one strain with potential probiotic effect] to the stresses induced by low and high incubation temperatures, acidity, NaCl, and bile salts, often encountered during the technological processes in food or during the passage through the human gastro-intestinal tract. The strains were able to grow at temperatures up to 40 °C (the mesophilic strains) and 47 °C (the thermophilic strain), in medium with an initial pH of at least 4.0 (Lactobacillus acidophilus IBB801), or in the presence of NaCl up to 10% (Weissella confusa/cibaria 38.2), or bile salts up to 0.2% (L. acidophilus IBB801). The protein and isoenzyme patterns of the strains subjected to various stress conditions presented several differences compared with the control patterns, among which the overexpression of some proteins of about 50-60 kDa, differences in the bands intensity in the case of the intracellular enzymes, or the complete loss of some of these bands. The best survival to low pH values and high temperatures was observed for strain L. acidophilus IBB801, the candidate probiotic strain. The EPS production of the four tested strains was, in general, directly related to the growth, the highest yields being obtained when strains were incubated at 24 °C. PMID:23933743

  18. Salicylic acid induces differential antioxidant response in spring maize under high temperature stress.

    Khanna, Palak; Kaur, Kamaljit; Gupta, Anil K

    2016-06-01

    High temperature is one of the important stress factors that affect crops in tropical countries. Plants do evolve or adopt different mechanisms to overcome such stress for survival. It is an interesting subject and has attracted many researchers to work upon. Here, we studied the effect of salicylic acid (SA) on seedling growth and antioxidative defense system in two spring maize (Zea mays L.) genotypes viz., CML-32 (relatively heat tolerant) and LM-11 (relatively heat susceptible), under high temperature stress. High temperature induced greater reduction in dry biomass of LM-1 1 seedlings as compared to those of CML-32. There was a parallel increase in ascorbate peroxidase and glutathione reductase activities in the roots of CML-32 seedlings. However, the activities of catalase and superoxide dismutase decreased and the contents of H202, proline and malonaldialdehyde (MDA) increased in seedlings of both the genotypes. Application of SA (400 µM) led to increased dry biomass in heat stressed CML-32 seedlings. It improved the efficiency of Halliwell-Asada pathway in roots of CML-32 seedlings as was evidenced by the enhanced ascorbate peroxidase and glutathione reductase activities. The activities of catalase and superoxide dismutase increased in both the tissues of LM-11 seedlings, whereas in CML-32, it was only in shoots, after SA application. Peroxidase activity increased in SA treated seedlings of both the genotypes, though the increase was comparatively higher in CML-32. The contents of H₂O₂ and MDA decreased and that of proline increased in SA treated seedlings of both the genotypes, under stress conditions. It may be concluded that SA induced differential antioxidant response by upregulating Halliwell-Asada pathway in roots and attaining high POX activity in both the tissues of CML-32 seedlings, under high temperature stress. PMID:27468465

  19. Decoding genome-wide GadEWX-transcriptional regulatory networks reveals multifaceted cellular responses to acid stress in Escherichia coli

    Seo, Sang Woo; Kim, Donghyuk; O'Brien, Edward J.;

    2015-01-01

    . We demonstrate that GadEWX directly and coherently regulate several proton-generating/consuming enzymes with pairs of negative-feedback loops for pH homeostasis. In addition, GadEWX regulate genes with assorted functions, including molecular chaperones, acid resistance, stress response and other...... comprehensively reconstruct the genome-wide GadEWX transcriptional regulatory network and RpoS involvement in E. coli K-12 MG1655 under acidic stress. Integrative data analysis reveals that GadEWX regulons consist of 45 genes in 31 transcription units and 28 of these genes were associated with RpoS-binding sites...... regulatory activities. These results show how GadEWX simultaneously coordinate many cellular processes to produce the overall response of E. coli to acid stress....

  20. The osmotic stress response of split influenza vaccine particles in an acidic environment

    Choi, Hyo-Jick; Kim, Min-Chul; Kang, Sang-Moo; Montemagno, Carlo D.

    2013-01-01

    Oral influenza vaccine provides an efficient means of preventing seasonal and pandemic disease. In this work, the stability of envelope-type split influenza vaccine particles in acidic environments has been investigated. Owing to the fact that hyper-osmotic stress can significantly affect lipid assembly of vaccine, osmotic stress-induced morphological change of split vaccine particles, in conjunction with structural change of antigenic proteins, was investigated by the use of stopped-flow lig...

  1. Movement of abscisic acid into the apoplast in response to water stress in Xanthium strumarium L

    Cornish, K.; Zeevaart, J.A.D.

    1985-07-01

    The effect of water stress on the redistribution of abscisic acid (ABA) in mature leaves of Xanthium strumarium L. was investigated using a pressure dehydration technique. In both turgid and stressed leaves, the ABA in the xylem exudate, the apoplastic ABA, increased before bulk leaf stress-induced ABA accumulation began. In the initially turgid leaves, the ABA level remained constant in both the apoplast and the leaf as a whole until wilting symptoms appeared. Following turgor loss, sufficient quantities of ABA moved into the apoplast to stimulate stomatal closure. Thus, the initial increase of apoplastic ABA may be relevant to the rapid stomatal closure seen in stressed leaves before their bulk leaf ABA levels rise. Following recovery from water stress, elevated levels of ABA remained in the apoplast after the bulk leaf contents had returned to their prestress values. This apoplastic ABA may retard stomatal reopening during the initial recovery period. 32 references, 5 figures.

  2. H2O2 mediates the crosstalk of brassinosteroid and abscisic acid in tomato responses to heat and oxidative stresses

    Zhou, Jie; Wang, Jian; Li, Xin; Xia, Xiao-Jian; Zhou, Yan-Hong; Shi, Kai; Chen, Zhixiang; Yu, Jing-Quan

    2014-01-01

    The production of H2O2 is critical for brassinosteroid (BR)- and abscisic acid (ABA)-induced stress tolerance in plants. In this study, the relationship between BR and ABA in the induction of H2O2 production and their roles in response to heat and paraquat (PQ) oxidative stresses were studied in tomato. Both BR and ABA induced increases in RBOH1 gene expression, NADPH oxidase activity, apoplastic H2O2 accumulation, and heat and PQ stress tolerance in wild-type plants. BR could only induced tr...

  3. Hormonal and Hydroxycinnamic Acids Profiles in Banana Leaves in Response to Various Periods of Water Stress

    Jalel Mahouachi

    2014-01-01

    Full Text Available The pattern of change in the endogenous levels of several plant hormones and hydroxycinnamic acids in addition to growth and photosynthetic performance was investigated in banana plants (Musa acuminata cv. “Grand Nain” subjected to various cycles of drought. Water stress was imposed by withholding irrigation for six periods with subsequent rehydration. Data showed an increase in abscisic acid (ABA and indole-3-acetic acid (IAA levels, a transient increase in salicylic acid (SA concentration, and no changes in jasmonic acid (JA after each period of drought. Moreover, the levels of ferulic (FA and cinnamic acids (CA were increased, and plant growth and leaf gas exchange parameters were decreased by drought conditions. Overall, data suggest an involvement of hormones and hydroxycinnamic acids in plant avoidance of tissue dehydration. The increase in IAA concentration might alleviate the senescence of survival leaves and maintained cell elongation, and the accumulation of FA and CA could play a key role as a mechanism of photoprotection through leaf folding, contributing to the effect of ABA on inducing stomatal closure. Data also suggest that the role of SA similarly to JA might be limited to a transient and rapid increase at the onset of the first period of stress.

  4. Involvement of ethylene in gibberellic acid-induced sulfur assimilation, photosynthetic responses, and alleviation of cadmium stress in mustard.

    Masood, Asim; Khan, M Iqbal R; Fatma, Mehar; Asgher, Mohd; Per, Tasir S; Khan, Nafees A

    2016-07-01

    The role of gibberellic acid (GA) or sulfur (S) in stimulation of photosynthesis is known. However, information on the involvement of ethylene in GA-induced photosynthetic responses and cadmium (Cd) tolerance is lacking. This work shows that ethylene is involved in S-assimilation, photosynthetic responses and alleviation of Cd stress by GA in mustard (Brassica juncea L.). Plants grown with 200 mg Cd kg(-1) soil were less responsive to ethylene despite high ethylene evolution and showed photosynthetic inhibition. Plants receiving 10 μM GA spraying plus 100 mg S kg(-1) soil supplementation exhibited increased S-assimilation and photosynthetic responses under Cd stress. Application of GA plus S decreased oxidative stress of plants grown with Cd and limited stress ethylene formation to the range suitable for promoting sulfur use efficiency (SUE), glutathione (GSH) production and photosynthesis. The role of ethylene in GA-induced S-assimilation and reversal of photosynthetic inhibition by Cd was substantiated by inhibiting ethylene biosynthesis with the use of aminoethoxyvinylglycine (AVG). The suppression of S-assimilation and photosynthetic responses by inhibiting ethylene in GA plus S treated plants under Cd stress indicated the involvement of ethylene in GA-induced S-assimilation and Cd stress alleviation. The outcome of the study is important to unravel the interaction between GA and ethylene and their role in Cd tolerance in plants. PMID:26998941

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

    Zhang, Xiujuan

    2013-06-01

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

  6. SaliCylic Acid-Altering Arabidopsis Mutants Response to Cd Stress

    Lu; Tian; Liang; Wu

    2012-01-01

    To evaluate the role of endogenous SA in plant response to Cd stress,Arabidopsis wild type(Columbia)and its SA-altering mutants snc1 (suppressor of npr1-1, constitutive) with high SA level, nahG(tansgenic line)with low SA level and npr1-1(non-expressor of PR gene)with SA signaling blockage were used in this study. Results showed that a greater growth inhibition occurred in snc1,while a less inhibition was observed in nahG and npr1-1 plants. Although the anti-oxidative enzymes SOD and POD increased upon Cd exposure,they were insufficient to remove oxidative stress,especially in snc1 plants. The accumulations of soluble sugar and proline in the tested plants were positively related to their tolerance to Cd stress.

  7. Effect of exogenous application of salicylic acid on the drought stress responses ofGardenia jasminoides

    XiaMei Yao; Jing Ma; Jing Ji; Chun Ou; WenQiang Gao

    2016-01-01

    The alleviative effects of exogenous salicylic acid (SA) on plants against drought stress were assessed inGardenia jasminoides seedlings treated with different concentrations of SA. Drought stress was simulated to a moderate level by 15% polyethylene glycol (PEG) 6000 treatment.Seedlings exposed to 15% PEG for 14 days exhibited a decrease in aboveground and underground dry mass, seedling height, root length, relative water content, photosynthetic pigment content, net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), and water use efficiency. In PEG-stressed plants, the levels of proline, malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage rose significantly, whereas antioxidative activity, including superoxide, peroxidase, and catalase activities, declined in leaves. However, the presence of SA provided an effective method of mitigating PEG-caused physiological stresses on G. jasminoides seedlings, which depended on SA levels. PEG-treated plants exposed to SA at 0.5–1.0 mmol/L signif-icantly eased PEG-induced growth inhibition. Application of SA, especially at concentrations of 0.5–1.0 mmol/L, considerably improved photosynthetic pigments, photosynthesis, antioxidative activity, relative water content, and proline accumulation, and decreased MDA content, H2O2 content, and electrolyte leakage. By contrast, the positive effects were not evident, or even more severe, in PEG+SA4 treatment. Based on these physiological and biochemical data, a suitable concentration of SA, potential growth regulators, could be applied to enhance the drought tolerance of G. jasminoides.

  8. Molecular cloning and characterization of drought stress responsive abscisic acid-stress-ripening (Asr 1) gene from wild jujube, Ziziphus nummularia (Burm.f.) Wight & Arn.

    Padaria, Jasdeep Chatrath; Yadav, Radha; Tarafdar, Avijit; Lone, Showkat Ahmad; Kumar, Kanika; Sivalingam, Palaiyur Nanjappan

    2016-08-01

    Drought is a calamitous abiotic stress hampering agricultural productivity all over the world and its severity is likely to increase further. Abscisic acid-stress-ripening proteins (ASR), are a group of small hydrophilic proteins which are induced by abscisic acid, stress and ripening in many plants. In the present study, ZnAsr 1 gene was fully characterized for the first time from Ziziphus nummularia, which is one of the most low water forbearing plant. Full length ZnAsr 1 gene was characterised and in silico analysis of ZnASR1 protein was done for predicting its phylogeny and physiochemical properties. To validate transcriptional pattern of ZnAsr 1 in response to drought stress, expression profiling in polyethylene glycol (PEG) induced Z. nummularia seedlings was studied by RT-qPCR analysis and heterologous expression of the recombinant ZnAsr1 in Escherichia coli. The nucleotide sequence analysis revealed that the complete open reading frame of ZnAsr 1 is 819 bp long encoding a protein of 273 amino acid residues, consisting of a histidine rich N terminus with an abscisic acid/water deficit stress domain and a nuclear targeting signal at the C terminus. In expression studies, ZnAsr 1 gene was found to be highly upregulated under drought stress and recombinant clones of E. coli cells expressing ZnASR1 protein showed better survival in PEG containing media. ZnAsr1 was proven to enhance drought stress tolerance in the recombinant E.coli cells expressing ZnASR1. The cloned ZnAsr1 after proper validation in a plant system, can be used to develop drought tolerant transgenic crops. PMID:27209581

  9. Growth, Gas Exchange, Abscisic Acid, and Calmodulin Response to Salt Stress in Three Poplars

    2006-01-01

    In the present study, we investigated the effects of increasing salinity on growth, gas exchange, abscisic acid(ABA), calmodulin (CAM), and the relevance to salt tolerance in seedlings of Populus euphratica Oliv. and cuttings of P. "pupularis 35-44" (P. popularis) and P. x euramericana cv. 1-214 (P. cv. Italica). The relative growth rates of shoot height (RGRH) for P. cv. Italica and P. popularis were severely reduced by increasing salt stress,whereas the growth reduction was relatively less in P. euphratica. Similarly, P. euphratica maintained higher net photosynthetic rates (Pn) and unit transpiration rates (TRN) than P. cv. Italica and P. popularis under conditions of higher salinity. Salinity caused a significant increase in leaf ABA and CaM in the three genotypes after the onset of stress, but NaCl-induced ABA and CaM accumulation was more pronounced in P. euphratica,suggesting that P. euphratica plants are more sensitive in sensing soil salinity than the other two poplars.Furthermore, P. euphratica maintained relatively higher ABA and CaM concentrations under conditions of high salinity. The higher capacity to synthesize stress signals, namely ABA and CaM, in P. euphratica and the contribution of this to the salt resistance of P. euphratica are discussed.

  10. Lipidomic profiling of Saccharomyces cerevisiae and Zygosaccharomyces bailii reveals critical changes in lipid composition in response to acetic acid stress.

    Lina Lindberg

    Full Text Available When using microorganisms as cell factories in the production of bio-based fuels or chemicals from lignocellulosic hydrolysate, inhibitory concentrations of acetic acid, released from the biomass, reduce the production rate. The undissociated form of acetic acid enters the cell by passive diffusion across the lipid bilayer, mediating toxic effects inside the cell. In order to elucidate a possible link between lipid composition and acetic acid stress, the present study presents detailed lipidomic profiling of the major lipid species found in the plasma membrane, including glycerophospholipids, sphingolipids and sterols, in Saccharomyces cerevisiae (CEN.PK 113_7D and Zygosaccharomyces bailii (CBS7555 cultured with acetic acid. Detailed physiological characterization of the response of the two yeasts to acetic acid has also been performed in aerobic batch cultivations using bioreactors. Physiological characterization revealed, as expected, that Z. bailii is more tolerant to acetic acid than S. cerevisiae. Z. bailii grew at acetic acid concentrations above 24 g L(-1, while limited growth of S. cerevisiae was observed after 11 h when cultured with only 12 g L(-1 acetic acid. Detailed lipidomic profiling using electrospray ionization, multiple-reaction-monitoring mass spectrometry (ESI-MRM-MS showed remarkable changes in the glycerophospholipid composition of Z. bailii, including an increase in saturated glycerophospholipids and considerable increases in complex sphingolipids in both S. cerevisiae (IPC 6.2×, MIPC 9.1×, M(IP2C 2.2× and Z. bailii (IPC 4.9×, MIPC 2.7×, M(IP2C 2.7×, when cultured with acetic acid. In addition, the basal level of complex sphingolipids was significantly higher in Z. bailii than in S. cerevisiae, further emphasizing the proposed link between lipid saturation, high sphingolipid levels and acetic acid tolerance. The results also suggest that acetic acid tolerance is associated with the ability of a given strain to

  11. Response of peroxidase and catalase to acid rain stress during seed germination of rice, wheat, and rape

    Lihong WANG; Xiaohua HUANG; Qing ZHOU

    2008-01-01

    Seed germination of plants with various acid-resistance display different responses to acid rain. To understand the reason why such differences occur, the effects of simulated acid rain (pH 2.5-5.0) on the activities of peroxidase (ROD) and catalase (CAT) during seed ger-mination of rice (O. sativa),-wheat (T. aestivum), and rape (B. chinensis var. oleifera) were investigated. Results indi-cated that the maximum change in activities of CAT and POD by acid rain treatment with different acidity and time in relation to the referent treatment without acid rain, was in the order: rice (28.8%, 31.7%)wheat (4.0)>rape (5.0). Moreover, the change in activity of POD was higher than that of CAT, which showed that POD was more sensitive to acid rain stress than CAT. The difference in the ability of POD and CAT in removing free radicals was one reason why the germina-tion indexes of these three species behaved differently.

  12. Acidic pH shock induces the expressions of a wide range of stress-response genes

    Hong Soon-Kwang

    2008-12-01

    Full Text Available Abstract Background Environmental signals usually enhance secondary metabolite production in Streptomycetes by initiating complex signal transduction system. It is known that different sigma factors respond to different types of stresses, respectively in Streptomyces strains, which have a number of unique signal transduction mechanisms depending on the types of environmental shock. In this study, we wanted to know how a pH shock would affect the expression of various sigma factors and shock-related proteins in S. coelicolor A3(2. Results According to the results of transcriptional and proteomic analyses, the major number of sigma factor genes were upregulated by an acidic pH shock. Well-studied sigma factor genes of sigH (heat shock, sigR (oxidative stress, sigB (osmotic shock, and hrdD that play a major role in the secondary metabolism, were all strongly upregulated by the pH shock. A number of heat shock proteins including the DnaK family and chaperones such as GroEL2 were also observed to be upregulated by the pH shock, while their repressor of hspR was strongly downregulated. Oxidative stress-related proteins such as thioredoxin, catalase, superoxide dismutase, peroxidase, and osmotic shock-related protein such as vesicle synthases were also upregulated in overall. Conclusion From these observations, an acidic pH shock was considered to be one of the strongest stresses to influence a wide range of sigma factors and shock-related proteins including general stress response proteins. The upregulation of the sigma factors and shock proteins already found to be related to actinorhodin biosynthesis was considered to have contributed to enhanced actinorhodin productivity by mediating the pH shock signal to regulators or biosynthesis genes for actinorhodin production.

  13. Rapid Phosphatidic Acid Accumulation in Response to Low Temperature Stress in Arabidopsis is Generated through Diacylglycerol Kinase

    Steven A. Arisz

    2013-01-01

    Full Text Available Phosphatidic acid (PtdOH is emerging as an important signalling lipid in abiotic stress responses in plants. The effect of cold stress was monitored using 32P-labelled seedlings and leaf discs of Arabidopsis thaliana. Low, non-freezing temperatures were found to trigger a very rapid 32P-PtdOH increase, peaking within 2 and 5 min, respectively. In principle, PtdOH can be generated through three different pathways, i.e. i via de novo phospholipid biosynthesis (through acylation of lyso-PtdOH, ii via phospholipase D hydrolysis of structural phospholipids or iii via phosphorylation of diacylglycerol (DAG by DAG kinase (DGK. Using a differential 32P-labelling protocol and a PLD-transphosphatidylation assay, evidence is provided that the rapid 32P-PtdOH response was primarily generated through DGK. A simultaneous decrease in the levels of 32P-PtdInsP, correlating in time, temperature dependency and magnitude with the increase in 32P-PtdOH, suggested that a PtdInsP-hydrolyzing PLC generated the DAG in this reaction. Testing T-DNA insertion lines available for the seven DGK genes, revealed no clear changes in 32P-PtdOH responses, suggesting functional redundancy. Similarly, known cold-stress mutants were analyzed to investigate whether the PtdOH response acted downstream of the respective gene products. The hos1, los1 and fry1 mutants were found to exhibit normal PtdOH responses. Slight changes were found for ice1, snow1, and the overexpression line Super-ICE1, however, this was not cold-specific and likely due to pleiotropic effects. A tentative model illustrating direct cold effects on phospholipid metabolism is presented.

  14. Polyphenolic responses of grapevine berries to light, temperature, oxidative stress, abscisic acid and jasmonic acid show specific developmental-dependent degrees of metabolic resilience to perturbation.

    Degu, Asfaw; Ayenew, Biruk; Cramer, Grant R; Fait, Aaron

    2016-12-01

    Grape-berries are exposed to a plethora of abiotic and biotic stimuli during their development. The developmental and temporal regulation of grape berry polyphenol metabolism in response to various cues was investigated using LC-QTOF-MS based metabolite profiling. High light (2500μmolm(-2)s(-1)), high temperature (40°C), jasmonic acid (200μM), menadione (120μM) and abscisic acid (3.026mM) treatments were applied to detached berries. Greater magnitudes of metabolite fluctuations characterize the pre-veraison berries than the veraison stage in response to the treatments. Furthermore, a tighter co-response of metabolic processes was shown at veraison, likely supporting the resilience to change in response to stress. High temperature and ABA treatments led to greater magnitudes of change during the course of the experiment. The present study demonstrates the occurrence of differential patterns of metabolic responses specific to individual cues and berry developmental stage, which in the field are commonly associated and thus hardly discernable. PMID:27374601

  15. Population Heterogeneity of Lactobacillus plantarum WCFS1 Microcolonies in Response to and Recovery from Acid Stress

    Ingham, C.J.; Beerthuyzen, M.; Vlieg, J.E.T.V.H.

    2008-01-01

    Within an isogenic microbial population in a homogenous environment, individual bacteria can still exhibit differences in phenotype. Phenotypic heterogeneity can facilitate the survival of subpopulations under stress. As the gram-positive bacterium Lactobacillus plantarum grows, it acidifies the gro

  16. Response of Halomonas campisalis to saline stress: changes in growth kinetics, compatible solute production and membrane phospholipid fatty acid composition.

    Aston, John E; Peyton, Brent M

    2007-09-01

    The haloalkaliphile Halomonas campisalis, isolated near Soap Lake, Washington, was grown under both aerobic and denitrifying conditions from 0 to 260 g L(-1) NaCl, with optimal growth occurring at 20 and 30 g L(-1) NaCl, respectively. Halomonas campisalis was observed to produce high concentrations of compatible solutes, most notably ectoine (up to 500 mM within the cytoplasm), but hydroxyectoine and glycine betaine were also detected. The types and amounts of compatible solutes produced depended on salinity and specific growth rate, as well as on the terminal electron acceptor available (O(2) or NO(3) (-)). A decrease in ectoine production was observed with NO(3) (-) as compared with O(2) as the terminal electron acceptor. In addition, changes in the phospholipid fatty acid composition were measured with changing salinity. An increase in trans fatty acids was observed in the absence of salinity, and may be a response to membrane instability. Cyclic fatty acids were also observed to increase, both in the absence of salinity, and at very high salinities, indicating cell stress at these conditions. PMID:17651393

  17. The Juvenile Phase of Maize Sees Upregulation of Stress-Response Genes and Is Extended by Exogenous Jasmonic Acid.

    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. PMID:27307257

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

    Li, Baohai

    2012-10-12

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

  19. Monitoring Plant Hormones During Stress Responses

    Engelberth, Marie J.; Engelberth, Jurgen

    2009-01-01

    Plant hormones and related signaling compounds play an important role in the regulation of plant responses to various environmental stimuli and stresses. Among the most severe stresses are insect herbivory, pathogen infection, and drought stress. For each of these stresses a specific set of hormones and/or combinations thereof are known to fine-tune the responses, thereby ensuring the plant's survival. The major hormones involved in the regulation of these responses are jasmonic acid (JA), sa...

  20. Interleukin-6 deficiency reduces the brain inflammatory response and increases oxidative stress and neurodegeneration after kainic acid-induced seizures

    Penkowa, M; Molinero, A; Carrasco, J;

    2001-01-01

    and were killed six days later. Morphological damage to the hippocampal field CA1-CA3 was seen after kainic acid treatment. Reactive astrogliosis and microgliosis were prominent in kainic acid-injected normal mice hippocampus, and clear signs of increased oxidative stress were evident. Thus...... was caused by kainic acid, as revealed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling and interleukin-1beta converting enzyme/Caspase-1 stainings. In kainic acid-injected interleukin-6 null mice, reactive astrogliosis and microgliosis were reduced, while...... morphological hippocampal damage, oxidative stress and apoptotic neuronal death were increased. Since metallothionein-I+II levels were lower, and those of inducible nitric oxide synthase higher, these concomitant changes are likely to contribute to the observed increased oxidative stress and neuronal death...

  1. Plant Responses to Water Stress as Affected by Abscisic Acid and Benzyladenine

    Pospíšilová, Jana; Haisel, Daniel; Schnablová, Renáta; Synková, Helena; Baťková, Petra

    Montreal : International Society of Photosynthesis , 2005 - (Van der Est, A.; Bruce, D.), s. 593-595 R&D Projects: GA ČR GA522/02/1099 Institutional research plan: CEZ:AV0Z50380511 Keywords : abscisic acid * benzyladenine * chlorophyl content Subject RIV: ED - Physiology

  2. A consolidated analysis of the physiologic and molecular responses induced under acid stress in the legume-symbiont model-soil bacterium Sinorhizobium meliloti.

    Draghi, W O; Del Papa, M F; Hellweg, C; Watt, S A; Watt, T F; Barsch, A; Lozano, M J; Lagares, A; Salas, M E; López, J L; Albicoro, F J; Nilsson, J F; Torres Tejerizo, G A; Luna, M F; Pistorio, M; Boiardi, J L; Pühler, A; Weidner, S; Niehaus, K; Lagares, A

    2016-01-01

    Abiotic stresses in general and extracellular acidity in particular disturb and limit nitrogen-fixing symbioses between rhizobia and their host legumes. Except for valuable molecular-biological studies on different rhizobia, no consolidated models have been formulated to describe the central physiologic changes that occur in acid-stressed bacteria. We present here an integrated analysis entailing the main cultural, metabolic, and molecular responses of the model bacterium Sinorhizobium meliloti growing under controlled acid stress in a chemostat. A stepwise extracellular acidification of the culture medium had indicated that S. meliloti stopped growing at ca. pH 6.0-6.1. Under such stress the rhizobia increased the O2 consumption per cell by more than 5-fold. This phenotype, together with an increase in the transcripts for several membrane cytochromes, entails a higher aerobic-respiration rate in the acid-stressed rhizobia. Multivariate analysis of global metabolome data served to unequivocally correlate specific-metabolite profiles with the extracellular pH, showing that at low pH the pentose-phosphate pathway exhibited increases in several transcripts, enzymes, and metabolites. Further analyses should be focused on the time course of the observed changes, its associated intracellular signaling, and on the comparison with the changes that operate during the sub lethal acid-adaptive response (ATR) in rhizobia. PMID:27404346

  3. Contrastive response of Brassica napus L. to exogenous salicylic acid, selenium and silicon supplementation under water stress

    Habibi Ghader

    2015-01-01

    The present research was designed to determine the effects of exogenous salicylic acid (SA), selenium (Se) and silicon (Si) on the resistance of canola (Brassica napus L. cv Okapi) seedlings to salt stress. Foliar application of SA (0.1 mM) in canola plants under drought stress for 25 days exhibited a significantly positive effect on shoot dry mass and raised the levels of total chlorophyll as well as boosting the activity of superoxide dismutase (SOD) and ...

  4. Physiological responses of Brassica napus to fulvic acid under water stress: Chlorophyll a fluorescence and antioxidant enzyme activity

    Ramin Lotfi

    2015-10-01

    Full Text Available The ameliorative effect of fulvic acid (0, 300, and 600 mg L− 1 on photosystem II and antioxidant enzyme activity of the rapeseed (Brassica napus L. plant under water stress (60, 100, and 140 mm evaporation from class A pan was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid (FA improved the maximum quantum efficiency of PSII (Fv/Fm and performance index (PI of plants under both well-watered and limited-water conditions. The time span from Fo to Fm and the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species (ROS is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

  5. Physiological responses of Brassica napus to fulvic acid under water stress: Chlorophyll a fluorescence and antioxidant enzyme activity

    Ramin; Lotfi; Mohammad; Pessarakli; Puriya; Gharavi-Kouchebagh; Hossein; Khoshvaghti

    2015-01-01

    The ameliorative effect of fulvic acid(0, 300, and 600 mg L-1) on photosystem II and antioxidant enzyme activity of the rapeseed(Brassica napus L.) plant under water stress(60, 100, and 140 mm evaporation from class A pan) was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid(FA) improved the maximum quantum efficiency of PSII(Fv/Fm)and performance index(PI) of plants under both well-watered and limited-water conditions. The time span from Foto Fmand the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species(ROS) is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

  6. Physiological responses of Brassica napus to fulvic acid under water stress:Chlorophyll a fluorescence and antioxidant enzyme activity

    Ramin Lotfi; Mohammad Pessarakli; Puriya Gharavi-Kouchebagh; Hossein Khoshvaghti

    2015-01-01

    The ameliorative effect of fulvic acid (0, 300, and 600 mg L−1) on photosystem II and antioxidant enzyme activity of the rapeseed (Brassica napus L.) plant under water stress (60, 100, and 140 mm evaporation from class A pan) was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid (FA) improved the maximum quantum efficiency of PSII (Fv/Fm) and performance index (PI) of plants under both well-watered and limited-water conditions. The time span from Fo to Fm and the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species (ROS) is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

  7. Effects of supplemental ascorbic acid on humeral immune response in broilers reared under heat-stress condition

    Vahel J. A. Amedy,

    2011-07-01

    Full Text Available An experiment was conducted to evaluate the efficacy of supplemental ascorbic acid (Vitamin C on the haemagglutination inhibition (HI and enzyme linked immune sorbent assay (ELISA antibody titer of the commercial broiler chicks vaccinated against Newcastle disease (ND virus, reared under heat stress condition. A total of 420, one day-old broiler chicks were randomly divided into 4 groups and kept under elevated summer temperature and treated with four levels of added ascorbic acid i.e., 0 (control group, 200, 400, 600 mg/kg in diets for 28 days, from 21 to 49 days of experimental period. HI antibody titer and ELISA antibody titer against ND virus were significantly (P<0.05 higher at 600 mg/kg Vitamin C in the diet than the others treatments. Apparently, adding ascorbic acid at 600 mg/kg in the diet could improve humoral immunity in broilers reared under heat stress.

  8. Auxin response under osmotic stress.

    Naser, Victoria; Shani, Eilon

    2016-08-01

    The phytohormone auxin (indole-3-acetic acid, IAA) is a small organic molecule that coordinates many of the key processes in plant development and adaptive growth. Plants regulate the auxin response pathways at multiple levels including biosynthesis, metabolism, transport and perception. One of the most striking aspects of plant plasticity is the modulation of development in response to changing growth environments. In this review, we explore recent findings correlating auxin response-dependent growth and development with osmotic stresses. Studies of water deficit, dehydration, salt, and other osmotic stresses point towards direct and indirect molecular perturbations in the auxin pathway. Osmotic stress stimuli modulate auxin responses by affecting auxin biosynthesis (YUC, TAA1), transport (PIN), perception (TIR/AFB, Aux/IAA), and inactivation/conjugation (GH3, miR167, IAR3) to coordinate growth and patterning. In turn, stress-modulated auxin gradients drive physiological and developmental mechanisms such as stomata aperture, aquaporin and lateral root positioning. We conclude by arguing that auxin-mediated growth inhibition under abiotic stress conditions is one of the developmental and physiological strategies to acclimate to the changing environment. PMID:27052306

  9. The pepper late embryogenesis abundant protein CaLEA1 acts in regulating abscisic acid signaling, drought and salt stress response.

    Lim, Chae Woo; Lim, Sohee; Baek, Woonhee; Lee, Sung Chul

    2015-08-01

    As sessile organisms, plants are constantly challenged by environmental stresses, including drought and high salinity. Among the various abiotic stresses, osmotic stress is one of the most important factors for growth and significantly reduces crop productivity in agriculture. Here, we report a function of the CaLEA1 protein in the defense responses of plants to osmotic stress. Our analyses showed that the CaLEA1 gene was strongly induced in pepper leaves exposed to drought and increased salinity. Furthermore, we determined that the CaLEA1 protein has a late embryogenesis abundant (LEA)_3 homolog domain highly conserved among other known group 5 LEA proteins and is localized in the processing body. We generated CaLEA1-silenced peppers and CaLEA1-overexpressing (OX) transgenic Arabidopsis plants to evaluate their responses to dehydration and high salinity. Virus-induced gene silencing of CaLEA1 in pepper plants conferred enhanced sensitivity to drought and salt stresses, which was accompanied by high levels of lipid peroxidation in dehydrated and NaCl-treated leaves. CaLEA1-OX plants exhibited enhanced sensitivity to abscisic acid (ABA) during seed germination and in the seedling stage; furthermore, these plants were more tolerant to drought and salt stress than the wild-type plants because of enhanced stomatal closure and increased expression of stress-responsive genes. Collectively, our data suggest that CaLEA1 positively regulates drought and salinity tolerance through ABA-mediated cell signaling. PMID:25302464

  10. Functional annotation of the transcriptome of Sorghum bicolor in response to osmotic stress and abscisic acid

    Kumari Sunita; Klein Robert R; Olsen Andrew; Monaco Marcela K; Dugas Diana V; Ware Doreen; Klein Patricia E

    2011-01-01

    Abstract Background Higher plants exhibit remarkable phenotypic plasticity allowing them to adapt to an extensive range of environmental conditions. Sorghum is a cereal crop that exhibits exceptional tolerance to adverse conditions, in particular, water-limiting environments. This study utilized next generation sequencing (NGS) technology to examine the transcriptome of sorghum plants challenged with osmotic stress and exogenous abscisic acid (ABA) in order to elucidate genes and gene network...

  11. Biocide tolerance, phenotypic and molecular response of lactic acid bacteria isolated from naturally-fermented Aloreña table to different physico-chemical stresses.

    Casado Muñoz, María Del Carmen; Benomar, Nabil; Lavilla Lerma, Leyre; Knapp, Charles W; Gálvez, Antonio; Abriouel, Hikmate

    2016-12-01

    Lactic acid bacteria (LAB) isolated throughout the fermentation process of Aloreña table olives were found to be resistant at least to three antibiotics (Casado Muñoz et al., 2014); however, most were sensitive to the biocides tested in this study (with minimum inhibitory concentrations [MIC] below the epidemiological cut-off values). 2-15% of the isolates were found to be biocide resistant: Leuconostoc Pseudomesenteroides, which were resistant to hexachlorophene, and Lactobacillus pentosus to cetrimide and hexadecylpiridinium. We analyzed the effect of different physico-chemical stresses, including antimicrobials, on the phenotypic and genotypic responses of LAB, providing new insights on how they become resistant in a changing environment. Results indicated that similar phenotypic responses were obtained under three stress conditions: antimicrobials, chemicals and UV light. Susceptibility patterns to antibiotics changed: increasing MICs for ampicillin, chloramphenicol, ciprofloxacin, teicoplanin and tetracycline, and decreasing the MICs for clindamycin, erythromycin, streptomycin and trimethoprim in most strains. Statistically, cross resistance between different antibiotics was detected in all stress conditions. However, expression profiles of selected genes involved in stress/resistance response (rpsL, recA, uvrB and srtA) differed depending on the stress parameter, LAB species and strain, and the target gene. We conclude that, despite the uniform phenotypic response to stresses, the repertoire of induced and repressed genes differs. So, a search for a target to improve stress tolerance of LAB, especially those of importance as starter/protective cultures or probiotics, may depend on the individual screening of each strain, even though we could predict the antibiotic phenotypic response to all stresses. PMID:27554140

  12. The upregulation of thiamine (vitamin B1 biosynthesis in Arabidopsis thaliana seedlings under salt and osmotic stress conditions is mediated by abscisic acid at the early stages of this stress response

    Rapala-Kozik Maria

    2012-01-01

    Full Text Available Abstract Background Recent reports suggest that vitamin B1 (thiamine participates in the processes underlying plant adaptations to certain types of abiotic and biotic stress, mainly oxidative stress. Most of the genes coding for enzymes involved in thiamine biosynthesis in Arabidopsis thaliana have been identified. In our present study, we examined the expression of thiamine biosynthetic genes, of genes encoding thiamine diphosphate-dependent enzymes and the levels of thiamine compounds during the early (sensing and late (adaptation responses of Arabidopsis seedlings to oxidative, salinity and osmotic stress. The possible roles of plant hormones in the regulation of the thiamine contribution to stress responses were also explored. Results The expression of Arabidopsis genes involved in the thiamine diphosphate biosynthesis pathway, including that of THI1, THIC, TH1 and TPK, was analyzed for 48 h in seedlings subjected to NaCl or sorbitol treatment. These genes were found to be predominantly up-regulated in the early phase (2-6 h of the stress response. The changes in these gene transcript levels were further found to correlate with increases in thiamine and its diphosphate ester content in seedlings, as well as with the enhancement of gene expression for enzymes which require thiamine diphosphate as a cofactor, mainly α-ketoglutarate dehydrogenase, pyruvate dehydrogenase and transketolase. In the case of the phytohormones including the salicylic, jasmonic and abscisic acids which are known to be involved in plant stress responses, only abscisic acid was found to significantly influence the expression of thiamine biosynthetic genes, the thiamine diphosphate levels, as well as the expression of genes coding for main thiamine diphosphate-dependent enzymes. Using Arabidopsis mutant plants defective in abscisic acid production, we demonstrate that this phytohormone is important in the regulation of THI1 and THIC gene expression during salt stress

  13. The surgically induced stress response.

    Finnerty, Celeste C; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A; Herndon, David N

    2013-09-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes that induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress response, however, varies according to the severity of injury (surgical or traumatic). This spectrum of injuries and insults ranges from small lacerations to severe insults such as large poly-traumatic and burn injuries. Burn injuries provide an extreme model of trauma induced stress responses that can be used to study the long-term effects of a prolonged stress response. Although the stress response to acute trauma evolved to confer improved chances of survival following injury, in modern surgical practice the stress response can be detrimental. PMID:24009246

  14. Stress Physiology of Lactic Acid Bacteria.

    Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan

    2016-09-01

    Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. PMID:27466284

  15. Mutation of the NADH Oxidase Gene (nox) Reveals an Overlap of the Oxygen- and Acid-Mediated Stress Responses in Streptococcus mutans

    Derr, Adam M.; Faustoferri, Roberta C.; Betzenhauser, Matthew J.; Gonzalez, Kaisha; Marquis, Robert E.; Quivey, Robert G.

    2012-01-01

    NADH oxidase (Nox) is a flavin-containing enzyme used by Streptococcus mutans to reduce dissolved oxygen encountered during growth in the oral cavity. In this study, we characterized the role of the NADH oxidase in the oxidative and acid stress responses of S. mutans. A nox-defective mutant strain of S. mutans and its parental strain, the genomic type strain UA159, were exposed to various oxygen concentrations at pH values of 5 and 7 to better understand the adaptive mechanisms used by the or...

  16. The Surgically Induced Stress Response

    Finnerty, Celeste C.; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A.; Herndon, David N

    2013-01-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes which induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress respo...

  17. The Surgically Induced Stress Response

    Finnerty, Celeste C.; Mabvuure, Nigel Tapiwa; Ali, Arham; Kozar, Rosemary A.; Herndon, David N.

    2013-01-01

    The stress response to surgery, critical illness, trauma, and burns encompasses derangements of metabolic and physiological processes which induce perturbations in the inflammatory, acute phase, hormonal, and genomic responses. Hypermetabolism and hypercatabolism result, leading to muscle wasting, impaired immune function and wound healing, organ failure, and death. The surgery-induced stress response is largely similar to that triggered by traumatic injuries; the duration of the stress response, however, varies according to the severity of injury (surgical or traumatic). This spectrum of injuries and insults ranges from small lacerations to severe insults such as large poly-traumatic and burn injuries. Although the stress response to acute trauma evolved to improve chances of survival following injury, in modern surgical practice the stress response can be detrimental. PMID:24009246

  18. Nordihydroguaiaretic Acid from Creosote Bush (Larrea tridentata Mitigates 12-O-Tetradecanoylphorbol-13-Acetate-Induced Inflammatory and Oxidative Stress Responses of Tumor Promotion Cascade in Mouse Skin

    Shakilur Rahman

    2011-01-01

    Full Text Available Nordihydroguaiaretic acid (NDGA is a phenolic antioxidant found in the leaves and twigs of the evergreen desert shrub, Larrea tridentata (Sesse and Moc. ex DC Coville (creosote bush. It has a long history of traditional medicinal use by the Native Americans and Mexicans. The modulatory effects of topically applied NDGA was studied on acute inflammatory and oxidative stress responses in mouse skin induced by stage I tumor promoting agent, 12-O-tetradecanoylphorbol-13-acetate (TPA. Double TPA treatment adversely altered many of the marker responses of stage I skin tumor promotion cascade. Pretreatment of NDGA in TPA-treated mice mitigated cutaneous lipid peroxidation and inhibited production of hydrogen peroxide. NDGA treatment also restored reduced glutathione level and activities of antioxidant enzymes. Elevated activities of myeloperoxidase, xanthine oxidase and skin edema formation in TPA-treated mice were also lowered by NDGA indicating a restrained inflammatory response. Furthermore, results of histological study demonstrated inhibitory effect of NDGA on cellular inflammatory responses. This study provides a direct evidence of antioxidative and anti-inflammatory properties of NDGA against TPA-induced cutaneous inflammation and oxidative stress corroborating its chemopreventive potential against skin cancer.

  19. Responses of antioxidant enzyme and photosynthesis in rape seedling to the combined stresses of acid rain and ultraviolet-B radiation

    LIANG Chan-juan; HUANG Xiao-hua; TAO Wen-yi; ZHOU Qing

    2005-01-01

    Effects of the simulated acid rain(AR) and ultraviolet-B(UV-B, 280-320 nm) radiation with a single or two ways simultaneously (AR + UV-B) on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress(AR or UV-B) is stronger than that to dual stresses(AR +UV-B). Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation.According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability,M DA content and photosynthetic characteristics to the above-mentioned stresses was as follows: AR + UV-B > UV-B > AR.

  20. Effect of Poly(γ-glutamic acid) on the Physiological Responses and Calcium Signaling of Rape Seedlings (Brassica napus L.) under Cold Stress.

    Lei, Peng; Xu, Zongqi; Ding, Yan; Tang, Bao; Zhang, Yunxia; Li, Huashan; Feng, Xiaohai; Xu, Hong

    2015-12-01

    Cold stress adversely affects plant growth and development. Poly(γ-glutamic acid) (γ-PGA) is a potential plant growth regulator that may be an effective cryoprotectant that prevents crops from damage during cold weather. In this study, the effects of γ-PGA on the physiological responses of rape seedlings subject to cold stress were investigated using hydroponic experiments. We determined that the malondialdehyde content was decreased by 33.4% and the proline content was increased by 62.5% by γ-PGA after 144 h under cold stress. Antioxidant enzymes activities were also evidently enhanced after treatment with γ-PGA. These responses counteracted increases in the fresh weight and chlorophyll content of rape seedlings, which increased by 24.5 and 50.9%, respectively, after 144 h, which meant that growth inhibition caused by cold was mitigated by γ-PGA. Our results also showed that γ-PGA also regulated Ca(2+) concentrations in the cytoplasm and calcium-dependent protein kinases, which are associated with cold resistance. In conclusion, we suggest that the Ca(2+)/CPKs signal pathway is involved in the γ-PGA-mediated enhancement of cold resistance in rape seedlings. PMID:26585291

  1. Neuronal responses to physiological stress

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger David John

    2012-01-01

    damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses...... include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review...... the responses of neurons to various physiological stressors at the molecular and cellular level....

  2. Characterization of VuMATE1 expression in response to iron nutrition and aluminum stress reveals adaptation of rice bean (Vigna umbellata to acid soils through cis regulation

    Meiya eLiu

    2016-04-01

    Full Text Available Rice bean (Vigna umbellata VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acidic soils where Al stress imposed but Fe deficiency pressure released.

  3. Characterization of VuMATE1 Expression in Response to Iron Nutrition and Aluminum Stress Reveals Adaptation of Rice Bean (Vigna umbellata) to Acid Soils through Cis Regulation

    Liu, Meiya; Xu, Jiameng; Lou, Heqiang; Fan, Wei; Yang, Jianli; Zheng, Shaojian

    2016-01-01

    Rice bean (Vigna umbellata) VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acid soils where Al stress imposed but Fe deficiency pressure released.

  4. Neuronal responses to physiological stress

    Konstantinos eKagias

    2012-10-01

    Full Text Available Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. Physiological stress can be divided into three different aspects: environmental stress, intrinsic developmental stress and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature and redox state for example, trigger molecular events that enable an organism to adapt, survive and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, which result from an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level.

  5. An overview of stress response proteomes in Listeria monocytogenes

    Soni, K A; Nannapaneni, R; Tasara, T

    2011-01-01

    Listeria monocytogenes adapts to diverse stress conditions including cold, osmotic, heat, acid, and alkali stresses encountered during food processing and preservation which is a serious food safety threat. In this review, we have presented the major findings on this bacterium’s stress response proteomes to date along with the different approaches used for its proteomic analysis. The key proteome findings on cold, heat shock, salt, acid, alkaline and HHP stresses illustrate that the cellular ...

  6. Neuronal responses to physiological stress.

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

    2012-01-01

    Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, due to an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level. PMID:23112806

  7. Light and abiotic stresses regulate the expression of GDP-L-galactose phosphorylase and levels of ascorbic acid in two kiwifruit genotypes via light-responsive and stress-inducible cis-elements in their promoters.

    Li, Juan; Liang, Dong; Li, Mingjun; Ma, Fengwang

    2013-09-01

    Ascorbic acid (AsA) plays an essential role in plants by protecting cells against oxidative damage. GDP-L-galactose phosphorylase (GGP) is the first committed gene for AsA synthesis. Our research examined AsA levels, regulation of GGP gene expression, and how these are related to abiotic stresses in two species of Actinidia (kiwifruit). When leaves were subjected to continuous darkness or light, ABA or MeJA, heat, or a hypoxic environment, we found some correlation between the relative levels of GGP mRNA and AsA concentrations. In transformed tobacco plants, activity of the GGP promoter was induced by all of these treatments. However, the degree of inducibility in the two kiwifruit species differed among the GGP promoter deletions. We deduced that the G-box motif, a light-responsive element, may have an important function in regulating GGP transcripts under various light conditions in both A. deliciosa and A. eriantha. Other elements such as ABRE, the CGTCA motif, and HSE might also control the promoter activities of GGP in kiwifruit. Altogether, these data suggest that GGP expression in the two kiwifruit species is regulated by light or abiotic stress via the relative cis-elements in their promoters. Furthermore, GGP has a critical role in modulating AsA concentrations in kiwifruit species under abiotic stresses. PMID:23775440

  8. Drought stress responses in crops.

    Shanker, Arun K; Maheswari, M; Yadav, S K; Desai, S; Bhanu, Divya; Attal, Neha Bajaj; Venkateswarlu, B

    2014-03-01

    Among the effects of impending climate change, drought will have a profound impact on crop productivity in the future. Response to drought stress has been studied widely, and the model plant Arabidopsis has guided the studies on crop plants with genome sequence information viz., rice, wheat, maize and sorghum. Since the value of functions of genes, dynamics of pathways and interaction of networks for drought tolerance in plants can only be judged by evidence from field performance, this mini-review provides a research update focussing on the current developments on the response to drought in crop plants. Studies in Arabidopsis provide the basis for interpreting the available information in a systems biology perspective. In particular, the elucidation of the mechanism of drought stress response in crops is considered from evidence-based outputs emerging from recent omic studies in crops. PMID:24408129

  9. Abiotic stressors and stress responses

    Sulmon, Cecile; Van Baaren, Joan; Cabello-Hurtado, Francisco;

    2015-01-01

    Abstract Organisms are regularly subjected to abiotic stressors related to increasing anthropogenic activities, including chemicals and climatic changes that induce major stresses. Based on various key taxa involved in ecosystem functioning (photosynthetic microorganisms, plants, invertebrates), we...... review how organisms respond and adapt to chemical- and temperature-induced stresses from molecular to population level. Using field-realistic studies, our integrative analysis aims to compare i) how molecular and physiological mechanisms related to protection, repair and energy allocation can impact...... complexity. We provide new insights into the understanding of the impact of molecular and cellular responses on individual and population dynamics and assess the potential related effects on communities and ecosystem functioning....

  10. Cortical and subcortical gamma amino acid butyric acid deficits in anxiety and stress disorders: Clinical implications

    Goddard, Andrew W

    2016-01-01

    Anxiety and stress disorders are a major public health issue. However, their pathophysiology is still unclear. The gamma amino acid butyric acid (GABA) neurochemical system has been strongly implicated in their pathogenesis and treatment by numerous preclinical and clinical studies, the most recent of which have been highlighted and critical review in this paper. Changes in cortical GABA appear related to normal personality styles and responses to stress. While there is accumulating animal an...

  11. Effect of Vitamin E and Omega-3 Fatty Acids on Protecting Ambient PM2.5-Induced Inflammatory Response and Oxidative Stress in Vascular Endothelial Cells

    Bo, Liang; Jiang, Shuo; Xie, Yuquan; Kan, Haidong; Song, Weimin; Zhao, Jinzhuo

    2016-01-01

    Although the mechanisms linking cardiopulmonary diseases to ambient fine particles (PM2.5) are still unclear, inflammation and oxidative stress play important roles in PM2.5-induced injury. It is well known that inflammation and oxidative stress could be restricted by vitamin E (Ve) or omega-3 fatty acids (Ω-3 FA) consumption. This study investigated the effects of Ve and Ω-3 FA on PM2.5-induced inflammation and oxidative stress in vascular endothelial cells. The underlying mechanisms linking PM2.5 to vascular endothelial injury were also explored. Human umbilical vein endothelial cells (HUVECs) were treated with 50 μg/mL PM2.5 in the presence or absence of different concentrations of Ve and Ω-3 FA. The inflammatory cytokines and oxidative stress markers were determined. The results showed that Ve induced a significant decrease in PM2.5-induced inflammation and oxidative stress. Malondialdehyde (MDA) in supernatant and reactive oxygen species (ROS) in cytoplasm decreased by Ve, while the superoxide dismutase (SOD) activity elevated. The inflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) also reduced by Ve. Moreover, Ω-3 FA played the same role on decreasing the inflammation and oxidative stress. IL-6 and TNF-α expressions were significantly lower in combined Ve with Ω-3 FA than treatment with Ve or Ω-3 FA alone. The Ve and Ω-3 FA intervention might abolish the PM2.5-induced oxidative stress and inflammation in vascular endothelial cells. There might be an additive effect of these two nutrients in mediating the PM2.5-induced injury in vascular endothelial cells. The results suggested that inflammation and oxidative stress might be parts of the mechanisms linking PM2.5 to vascular endothelial injury. PMID:27007186

  12. [Response of reactive oxygen metabolism in melon chloroplasts to short-term salinity-alkalinity stress regulated by exogenous γ-aminobutyric acid].

    Xiang, Li-xia; Hu, Li-pan; Hu, Xiao-hui; Pan, Xiong-bo; Ren, Wen-qi

    2015-12-01

    The regulatory effect of exogenous γ-aminobutyric acid (GABA) on metabolism of reactive oxygen species (ROS) in melon chloroplasts under short-term salinity-alkalinity stress were investigated in melon variety 'Jinhui No. 1', which was cultured with deep flow hydroponics. The result showed that under salinity-alkalinity stress, the photosynthetic pigment content, MDA content, superoxide anion (O₂·) production rate and hydrogen peroxide (H₂O₂) content in chloroplast increased significantly, the contents of antioxidants ascorbic acid (AsA) and glutathione (GSH) increased, and the activities of H⁺-ATPase and H⁺-PPiase were inhibited obviously. With exogenous GABA application, the accumulations of O₂·, MDA and H₂O₂ induced by salinity-alkalinity stress were inhibited. Exogenous GABA alleviated the increase of photosynthetic pigment content, improved the activity of SOD, enzymes of AsA-GSH cycle, total AsA and total GSH while decreased the AsA/DHA ratio and GSH/GSSH ratio. Foliar GABA could enhance the H⁺-ATPase and H⁺-PPiase activities. Our results suggested that the exogenous GABA could accelerate the ROS metabolism in chloroplast, promote the recycle of AsA-GSH, and maintain the permeability of cell membrane to improve the ability of melon chloroplast against salinity-alkalinity stress. PMID:27112014

  13. How plants handle multiple stresses: hormonal interactions underlying responses to abiotic stress and insect herbivory.

    Nguyen, Duy; Rieu, Ivo; Mariani, Celestina; van Dam, Nicole M

    2016-08-01

    Adaptive plant responses to specific abiotic stresses or biotic agents are fine-tuned by a network of hormonal signaling cascades, including abscisic acid (ABA), ethylene, jasmonic acid (JA) and salicylic acid. Moreover, hormonal cross-talk modulates plant responses to abiotic stresses and defenses against insect herbivores when they occur simultaneously. How such interactions affect plant responses under multiple stresses, however, is less understood, even though this may frequently occur in natural environments. Here, we review our current knowledge on how hormonal signaling regulates abiotic stress responses and defenses against insects, and discuss the few recent studies that attempted to dissect hormonal interactions occurring under simultaneous abiotic stress and herbivory. Based on this we hypothesize that drought stress enhances insect resistance due to synergistic interactions between JA and ABA signaling. Responses to flooding or waterlogging involve ethylene signaling, which likely reduces plant resistance to chewing herbivores due to its negative cross-talk with JA. However, the outcome of interactions between biotic and abiotic stress signaling is often plant and/or insect species-dependent and cannot simply be predicted based on general knowledge on the involvement of signaling pathways in single stress responses. More experimental data on non-model plant and insect species are needed to reveal general patterns and better understand the molecular mechanisms allowing plants to optimize their responses in complex environments. PMID:27095445

  14. Ascorbic Acid and/or 24-Epibrassinolide Trigger Physiological and Biochemical Responses for the Salt Stress Mitigation in Potato (Solanum tuberosum L.

    Chandrama Prakash Upadhyaya

    2015-12-01

    Full Text Available In the present study, we examined the role of ascorbic acid (AsA, vitamin C and/or 24-epibrassinolide (EBL, an active BR in mitigation of salt-induced stress in potato (Solanum tuberousum L. The 10-d-old plants were exposed to 150 mM NaCl and they were subsequently treated by ASA and/or EBL. The salt stress reduced significantly the plant growth, tuber yield, total chlorophyll and increased proline content and electrolyte leakage in the leaves. Toxic effects induced by salt stress were completely overcome by the combined exogenous application of AsA and EBL. The AsA and/or EBL treatments improved the growth parameters of the salt treated plants, such as shoot length, tuber number and size, fresh and dry mass and other physiological parameters. Our data also indicated that applications of AsA and EBL up-regulated the stress regulating plant hormone such as IAA, IBA and activities of the antioxidant enzymes, such as catalase (CAT, peroxidase (POX, superoxide dismutase (SOD, ascorbate peroxidase (APX and under salt stress.

  15. Crosstalk in Plant Responses to Biotic and Abiotic Stresses

    Keceli, Mehmet Ali

    2015-01-01

    In order to protect themselves against several biotic and abiotic stresses, plants are equipped with an array of defense mechanisms. Induced defenses and stress responses play a major role in plant disease resistance and are regulated by a network of interconnected signal transduction pathways with the plant hormones ethylene (ET), jasmonic acid (JA) and salicylic acid (SA) as the crucial mediators. These specific hormone-mediated signaling cascades trigger the expression of distinct sets of ...

  16. Hyperglycemic stress response in Crustacea

    S Lorenzon

    2005-09-01

    Full Text Available Blood glucose level in crustaceans is controlled by the crustacean Hyperglycemic Hormone (cHH,released from the eyestalk neuroendocrine centres both under physiological and environmental stressconditions. Hyperglycemia is a typical response of many aquatic animals to pollutants and stress and,in crustaceans, increased circulating cHH and hyperglycemia are reported to result from exposure toseveral environmental stressors. Biogenic amines and enkephalin have been found to mediate therelease of several neurohormones from crustacean neuroendocrine tissue and a model of thecontrolling network is proposed.

  17. Oxidative stress response after laparoscopic versus conventional sigmoid resection

    Madsen, Michael Tvilling; Kücükakin, Bülent; Lykkesfeldt, Jens; Rosenberg, Jacob; Gögenur, Ismail

    2012-01-01

    Surgery is accompanied by a surgical stress response, which results in increased morbidity and mortality. Oxidative stress is a part of the surgical stress response. Minimally invasive laparoscopic surgery may result in reduced oxidative stress compared with open surgery. Nineteen patients......, 1 h, 6 h, 24 h, 48 h, and 72 h postoperatively). There were no statistical significant differences between laparoscopic and open surgery for any of the 3 oxidative stress parameters. Malondialdehyde was reduced 1 hour postoperatively (P...... scheduled for sigmoid resection were randomly allocated to open or laparoscopic sigmoid resection in a double-blind, prospective clinical trial. Three biochemical markers of oxidative stress (malondialdehyde, ascorbic acid, and dehydroascorbic acid) were measured at 6 different time points (preoperatively...

  18. Abscisic Acid and Abiotic Stress Tolerance in Crop Plants

    Sah, Saroj K.; Reddy, Kambham R.; Li, Jiaxu

    2016-01-01

    Abiotic stress is a primary threat to fulfill the demand of agricultural production to feed the world in coming decades. Plants reduce growth and development process during stress conditions, which ultimately affect the yield. In stress conditions, plants develop various stress mechanism to face the magnitude of stress challenges, although that is not enough to protect them. Therefore, many strategies have been used to produce abiotic stress tolerance crop plants, among them, abscisic acid (ABA) phytohormone engineering could be one of the methods of choice. ABA is an isoprenoid phytohormone, which regulates various physiological processes ranging from stomatal opening to protein storage and provides adaptation to many stresses like drought, salt, and cold stresses. ABA is also called an important messenger that acts as the signaling mediator for regulating the adaptive response of plants to different environmental stress conditions. In this review, we will discuss the role of ABA in response to abiotic stress at the molecular level and ABA signaling. The review also deals with the effect of ABA in respect to gene expression. PMID:27200044

  19. Effects of ionizing radiations on 1-aminocyclo-propane-1-carloxylic acid metabolism in climateric fruits. Analysis of stress response and implication in fruit ripening

    Ethylene is a plant hormone which regulates many aspects of ripening, senescence and stress response. The results show that irradiation can also be considered as a stress factor. Ethylene production enhancement which follows irradiation is the consequence of ACC synthase activation, and results from a de novo synthesis of the enzyme and in some cases from a very fast (15 mn) translation of already presents mRNAS. In cherry tomatoe fruits the onset of the ripening process occurs earlier. This modification is the consequence of two contradictory effects: - the short term activation of the ACC metabolism. - the ionization impact on genome and the consecutive impairing of transcriptional processes. These two aspects are dependent on the irradiation dose. They bring in cherry tomatoes a synchronization of the ripening process. The stress response towards ionization and CuC12 was also investigated on cell fruit suspensions. Results are dependent on the stress nature, material and physiological cell condition. They confirm the previous observed activation of ACC synthesis, which seems to be a general feature in non senescent systems

  20. Cytoplasmic pH Response to Acid Stress in Individual Cells of Escherichia coli and Bacillus subtilis Observed by Fluorescence Ratio Imaging Microscopy

    Martinez, Keith A.; Ryan D Kitko; Mershon, J. Patrick; Adcox, Haley E.; Malek, Kotiba A.; Berkmen, Melanie B.; Slonczewski, Joan L.

    2012-01-01

    The ability of Escherichia coli and Bacillus subtilis to regulate their cytoplasmic pH is well studied in cell suspensions but is poorly understood in individual adherent cells and biofilms. We observed the cytoplasmic pH of individual cells using ratiometric pHluorin. A standard curve equating the fluorescence ratio with pH was obtained by perfusion at a range of external pH 5.0 to 9.0, with uncouplers that collapse the transmembrane pH difference. Adherent cells were acid stressed by switch...

  1. Sumo and the cellular stress response

    Enserink, Jorrit M.

    2015-01-01

    The ubiquitin family member Sumo has important functions in many cellular processes including DNA repair, transcription and cell division. Numerous studies have shown that Sumo is essential for maintaining cell homeostasis when the cell encounters endogenous or environmental stress, such as osmotic stress, hypoxia, heat shock, genotoxic stress, and nutrient stress. Regulation of transcription is a key component of the Sumo stress response, and multiple mechanisms have been described by which ...

  2. Transgenerational response to stress in Arabidopsis thaliana

    Boyko, Alex; Kovalchuk, Igor

    2010-01-01

    Plants exposed to stress pass the memory of exposure to stress to the progeny. Previously, we showed that the phenomenon of transgenerational memory of stress is of epigenetic nature and depends on the function of Dicer-like (DCL) 2 and DCL3 proteins. Here, we discuss a possible role of DNA methylation and function of small RNAs in establishing and maintaining transgenerational responses to stress. Our new data report that memory of stress is passed to the progeny predominantly through the fe...

  3. All-Trans Retinoic Acid Modulates DNA Damage Response and the Expression of the VEGF-A and MKI67 Genes in ARPE-19 Cells Subjected to Oxidative Stress.

    Tokarz, Paulina; Piastowska-Ciesielska, Agnieszka Wanda; Kaarniranta, Kai; Blasiak, Janusz

    2016-01-01

    Age-related macular degeneration (AMD) is characterized by the progressive degradation of photoreceptors and retinal pigment epithelium (RPE) cells. ARPE-19 is an RPE cell line established as an in vitro model for the study of AMD pathogenesis. Oxidative stress is an AMD pathogenesis factor that induces DNA damage. Thus, the oxidative stress-mediated DNA damage response (DDR) of ARPE-19 cells can be important in AMD pathogenesis. The metabolism of retinoids-which regulates cell proliferation, differentiation, and the visual cycle in the retina-was reported to be disturbed in AMD patients. In the present work, we studied the effect of all-trans retinoic acid (ATRA, a retinoid) on DDR in ARPE-19 cells subjected to oxidative stress. We observed that ATRA increased the level of reactive oxygen species (ROS), alkali-labile sites in DNA, DNA single-strand breaks, and cell death evoked by oxidative stress. ATRA did not modulate DNA repair or the distribution of cells in cell cycle in the response of ARPE-19 cells to oxidative stress. ATRA induced autophagy in the absence of oxidative stress, but had no effect on this process in the stress. ATRA induced over-expression of proliferation marker MKI67 and neovascularization marker VEGF-A. In conclusion, ATRA increased oxidative stress in ARPE-19 cells, resulting in more lesions to their DNA and cell death. Moreover, ATRA can modulate some properties of these cells, including neovascularization, which is associated with the exudative form of AMD. Therefore, ATRA can be important in the prevention, diagnosis, and therapy of AMD. PMID:27314326

  4. Phosphate-dependent root system architecture responses to salt stress

    Kawa, Dorota

    2016-05-20

    Nutrient availability and salinity of the soil affect growth and development of plant roots. Here, we describe how phosphate availability affects root system architecture (RSA) of Arabidopsis and how phosphate levels modulate responses of the root to salt stress. Phosphate (Pi) starvation reduced main root length and increased the number of lateral roots of Arabidopsis Col-0 seedlings. In combination with salt, low Pi dampened the inhibiting effect of mild salt stress (75mM) on all measured RSA components. At higher NaCl concentrations, the Pi deprivation response prevailed over the salt stress only for lateral root elongation. The Pi deprivation response of lateral roots appeared to be oppositely affected by abscisic acid (ABA) signaling compared to the salt stress response. Natural variation in the response to the combination treatment of salt and Pi starvation within 330 Arabidopsis accessions could be grouped into four response patterns. When exposed to double stress, in general lateral roots prioritized responses to salt, while the effect on main root traits was additive. Interestingly, these patterns were not identical for all accessions studied and multiple strategies to integrate the signals from Pi deprivation and salinity were identified. By Genome Wide Association Mapping (GWAS) 13 genomic loci were identified as putative factors integrating responses to salt stress and Pi starvation. From our experiments, we conclude that Pi starvation interferes with salt responses mainly at the level of lateral roots and that large natural variation exists in the available genetic repertoire of accessions to handle the combination of stresses.

  5. Stress responses in probiotic Lactobacillus casei.

    Hosseini Nezhad, Marzieh; Hussain, Malik Altaf; Britz, Margaret Lorraine

    2015-01-01

    Survival in harsh environments is critical to both the industrial performance of lactic acid bacteria (LAB) and their competitiveness in complex microbial ecologies. Among the LAB, members of the Lactobacillus casei group have industrial applications as acid-producing starter cultures for milk fermentations and as specialty cultures for the intensification and acceleration of flavor development in certain bacterial-ripened cheese varieties. They are amongst the most common organisms in the gastrointestinal (GI) tract of humans and other animals, and have the potential to function as probiotics. Whether used in industrial or probiotic applications, environmental stresses will affect the physiological status and properties of cells, including altering their functionality and biochemistry. Understanding the mechanisms of how LAB cope with different environments is of great biotechnological importance, from both a fundamental and applied perspective: hence, interaction between these strains and their environment has gained increased interest in recent years. This paper presents an overview of the important features of stress responses in Lb. casei, and related proteomic or gene expression patterns that may improve their use as starter cultures and probiotics. PMID:24915363

  6. Agreeableness, Extraversion, Stressor and Physiological Stress Response

    Xiaoyuan Chu; Zhentao Ma; Yuan Li; Jing Han

    2015-01-01

    Based on the theoretical analysis, with first-hand data collection and using multiple regression models, this study explored the relationship between agreeableness, extraversion, stressor and stress response and figured out interactive effect of agreeableness, extraversion, and stressor on stress response. We draw on the following conclusions: (1) the interaction term of stressor (work) and agreeableness can negatively predict physiological stress response; (2) the interaction term of stresso...

  7. Docosahexaenoic acid and palmitic acid reciprocally modulate monocyte activation in part through endoplasmic reticulum stress.

    Snodgrass, Ryan G; Huang, Shurong; Namgaladze, Dmitry; Jandali, Ola; Shao, Tiffany; Sama, Spandana; Brüne, Bernhard; Hwang, Daniel H

    2016-06-01

    Palmitic acid (C16:0) and TLR2 ligand induce, but docosahexaenoic acid (DHA) inhibits monocyte activation. C16:0 and TLR2 or TLR4 ligand induce certain ER stress markers; thus, we determined whether ER stress induced by these agonists is sufficient to induce monocyte activation, and whether the ER stress is inhibited by DHA which is known to inhibit C16:0- or ligand-induced TLR activation. Monocyte activation and ER stress were assessed by TLR/inflammasome-induced IL-1β production, and phosphorylation of IRE-1 and eIF2 and expression of CHOP, respectively in THP-1 cells. TLR2 ligand Pam3CSK4 induced phosphorylation of eIF2, but not phosphorylation of IRE-1 and CHOP expression. LPS also induced phosphorylation of both IRE-1 and eIF2 but not CHOP expression suggesting that TLR2 or TLR4 ligand, or C16:0 induces different ER stress responses. C16:0-, Pam3CSK4-, or LPS-induced IL-1β production was inhibited by 4-phenylbutyric acid, an inhibitor of ER stress suggesting that IL-1β production induced by these agonists is partly mediated through ER stress. Among two ER stress-inducing molecules, thapsigargin but not tunicamycin led to the expression of pro-IL-1β and secretion of IL-1β. Thus, not all types of ER stress are sufficient to induce inflammasome-mediated IL-1β secretion in monocytes. Although both C16:0 and thapsigargin-induced IL-1β secretion was inhibited by DHA, only C16:0-mediated ER stress was responsive to DHA. These findings suggest that the anti-inflammatory effects of DHA are at least in part mediated through modulating ER homeostasis and that the propensity of ER stress can be differentially modulated by the types of dietary fat we consume. PMID:27142735

  8. Neuronal responses to physiological stress

    Konstantinos eKagias; Camilla eNehammer; Roger ePocock

    2012-01-01

    Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. Physiological stress can be divided into three different aspects: environmental stress, intrinsic developmental stress and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature and redox state for example, trigger molecular events that enable an organism to adapt, survive and reproduce...

  9. Induction of aromatic amino acids and phenylpropanoid compounds in Scrophularia striata Boiss. cell culture in response to chitosan-induced oxidative stress.

    Kamalipourazad, Maryam; Sharifi, Mohsen; Maivan, Hassan Zare; Behmanesh, Mehrdad; Chashmi, Najmeh Ahmadian

    2016-10-01

    Manipulation of cell culture media by elicitors is one of most important strategies to inducing secondary metabolism for the production of valuable metabolites. In this investigation, inducing effect of chitosan on physiological, biochemical, and molecular parameters were investigated in cell suspension cultures of Scrophularia striata Boiss. The results showed that chitosan concentration and time of elicitation are determinants of the effectiveness of the elicitor. Accumulation of aromatic amino acids (phenylalanine [Phe] and tyrosine [Tyr]), phenylpropanoid compounds (phenolic acids [PAs] and echinacoside [ECH]), hydrogen peroxide (H2O2) production, phenylalanine ammonia-lyase (PAL) activity and gene expression, and antioxidant enzymes (superoxide dismutase [SOD], peroxidase [POX], catalase [CAT]) activities were altered by changing the exposure time of elicitation. Results showed that, upon elicitation with chitosan, oxidative events were induced, antioxidant responses of S. striata cells were boosted through enhanced activity of an effective series of scavenging enzymes (SOD, CAT, and POX), and biosynthesis of non-enzymatic antioxidants (ECH and PAs [cinnamic, p-coumaric and, caffeic acids]). The increase in amino acid content and PAL activity at early days of exposure to chitosan was related with rises in phenolic compounds. These results provide evidence that chitosan by up-regulation of PAL gene differentially improves the production of phenylpropanoid compounds, which are of medical commercial value with good biotechnological prospects. PMID:27392152

  10. Plant Core Environmental Stress Response Genes Are Systemically Coordinated during Abiotic Stresses

    Kenneth W. Berendzen

    2013-04-01

    Full Text Available Studying plant stress responses is an important issue in a world threatened by global warming. Unfortunately, comparative analyses are hampered by varying experimental setups. In contrast, the AtGenExpress abiotic stress experiment displays intercomparability. Importantly, six of the nine stresses (wounding, genotoxic, oxidative, UV-B light, osmotic and salt can be examined for their capacity to generate systemic signals between the shoot and root, which might be essential to regain homeostasis in Arabidopsis thaliana. We classified the systemic responses into two groups: genes that are regulated in the non-treated tissue only are defined as type I responsive and, accordingly, genes that react in both tissues are termed type II responsive. Analysis of type I and II systemic responses suggest distinct functionalities, but also significant overlap between different stresses. Comparison with salicylic acid (SA and methyl-jasmonate (MeJA responsive genes implies that MeJA is involved in the systemic stress response. Certain genes are predominantly responding in only one of the categories, e.g., WRKY genes respond mainly non-systemically. Instead, genes of the plant core environmental stress response (PCESR, e.g., ZAT10, ZAT12, ERD9 or MES9, are part of different response types. Moreover, several PCESR genes switch between the categories in a stress-specific manner.

  11. Feeding rumen-protected gamma-aminobutyric acid enhances the immune response and antioxidant status of heat-stressed lactating dairy cows.

    Cheng, Jianbo; Zheng, Nan; Sun, Xianzhi; Li, Songli; Wang, Jiaqi; Zhang, Yangdong

    2016-08-01

    This experiment was conducted to investigate the effects of rumen-protected gamma-aminobutyric acid (GABA) on immune function and antioxidant status in heat-stressed dairy cows. Sixty Holstein dairy cows were randomly assigned to 1 of 4 treatments according to a completely randomized block design. The treatments consisted of 0 (control), 40, 80, or 120mg of GABA/kg DM from rumen-protected GABA. The trial lasted 10 weeks. The average temperature-humidity indices at 0700, 1400 and 2200h were 78.4, 80.2 and 78.7, respectively. Rectal temperatures decreased linearly at 0700, 1400, and 2200h with increasing GABA. As the GABA increased, the immunoglobulin (Ig) A and IgG contents and the proportions of CD4(+) and CD8(+) T lymphocytes increased linearly (PAOC) increased linearly (P<0.05), whereas malondialdehyde (MDA) content decreased linearly (P<0.05) with increasing GABA. These results indicate that rumen-protected GABA supplementation to heat-stressed dairy cows can improve their immune function and antioxidant activity. PMID:27503722

  12. Neuronal Responses to Physiological Stress

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

    2012-01-01

    Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition t...

  13. Stress Generation and Adolescent Depression: Contribution of Interpersonal Stress Responses

    Flynn, Megan; Rudolph, Karen D.

    2011-01-01

    This research examined the proposal that ineffective responses to common interpersonal problems disrupt youths’ relationships, which, in turn, contributes to depression during adolescence. Youth (86 girls, 81 boys; M age = 12.41, SD = 1.19) and their primary female caregivers participated in a three-wave longitudinal study. Youth completed a measure assessing interpersonal stress responses; youth and caregivers completed semi-structured interviews assessing youths’ life stress and psychopatho...

  14. The Transcriptional Heat Shock Response of Salmonella Typhimurium Shows Hysteresis and Heated Cells Show Increased Resistance to Heat and Acid Stress

    Pin, C.; Hansen, Trine; Munoz-Cuevas, M.;

    2012-01-01

    -regulated genes, implying that down-regulation was significantly less synchronized than upregulation. The hysteretic transcriptional response to heat shock was accompanied by higher resistance to inactivation at 50uC as well as cross-resistance to inactivation at pH 3; however, growth rates and lag times at 43u...... 120 up-regulated genes during the heat shock remained up-regulated 30 minutes after the temperature was set back to 25uC, while only 86 out of 293 down regulated genes remained down regulated 30 minutes after the heat shock ceased. Thus, the majority of the induced genes exhibited hysteresis, i.......e., they remained up-regulated after the environmental stress ceased. At 25uC the transcriptional regulation of genes encoding for heat shock proteins was determined by the previous environment. Gene networks constructed with up-regulated genes were significantly more modular than those of down...

  15. General Stress Responses in the Honey Bee

    Naïla Even

    2012-12-01

    Full Text Available The biological concept of stress originated in mammals, where a “General Adaptation Syndrome” describes a set of common integrated physiological responses to diverse noxious agents. Physiological mechanisms of stress in mammals have been extensively investigated through diverse behavioral and physiological studies. One of the main elements of the stress response pathway is the endocrine hypothalamo-pituitary-adrenal (HPA axis, which underlies the “fight-or-flight” response via a hormonal cascade of catecholamines and corticoid hormones. Physiological responses to stress have been studied more recently in insects: they involve biogenic amines (octopamine, dopamine, neuropeptides (allatostatin, corazonin and metabolic hormones (adipokinetic hormone, diuretic hormone. Here, we review elements of the physiological stress response that are or may be specific to honey bees, given the economical and ecological impact of this species. This review proposes a hypothetical integrated honey bee stress pathway somewhat analogous to the mammalian HPA, involving the brain and, particularly, the neurohemal organ corpora cardiaca and peripheral targets, including energy storage organs (fat body and crop. We discuss how this system can organize rapid coordinated changes in metabolic activity and arousal, in response to adverse environmental stimuli. We highlight physiological elements of the general stress responses that are specific to honey bees, and the areas in which we lack information to stimulate more research into how this fascinating and vital insect responds to stress.

  16. Induction and Degradation of Phosphatidic Acid in the Response of Plants to Stresses%磷脂酸的诱导和降解在植物逆境响应中的作用

    张洁; 樊若溪; 李唯奇

    2011-01-01

    磷脂酸(phosphatidic acid,PA)是植物中重要的脂质信号分子,被称为"脂质第二信使",参与多种逆境胁迫相关的信号传导途径.植物体内的PA可通过直接的磷脂酶D途径和间接的磷脂酶C途径产生.当植物受到胁迫刺激后,细胞内的PA含量会在几分钟内升高,在胁迫消失后经磷酸化作用形成甘油二酯焦磷酸降解,恢复到正常水平.本文结合当前国内外的研究进展,就膜脂中PA的诱导和降解在植物逆境响应中的作用进行探讨与展望.%Phosphatidic acid (PA) is an important lipid signal molecule and emerge as a lipid second messenger in plants involved in various biotic and abiotic stress conditions. Two signaling pathways are predominantly responsible for its formation. PA is directly formed via activation of phospholipase D, and indirectly via activation of a phospholipase C pathway. The level of PA increases after a wide variety of stress treatments and goes back to the normal level when the stresses disappear. The enhanced signal level of PA is rapidly attenuated through the formation of diacylglycerol pyrophosphate via phosphorylating PA. In this paper, we discussed the research progress on the function of induction and degradation of PA in the response of plants to stresses.

  17. Soybean Toxin (SBTX) Impairs Fungal Growth by Interfering with Molecular Transport, Carbohydrate/Amino Acid Metabolism and Drug/Stress Responses

    Morais, Janne K. S.; Bader, Oliver; Weig, Michael; Oliveira, Jose Tadeu A.; Arantes, Mariana R.; Gomes, Valdirene M.; Da Cunha, Maura; Oliveira, Hermogenes D.; Sousa, Daniele O. B.; Lourencao, Andre L.; Vasconcelos, Ilka M.

    2013-01-01

    Soybean toxin (SBTX) is an antifungal protein from soybeans with broad inhibitory activity against the growth and filamentation of many fungi, including human and plant pathogenic species such as Candida albicans, Candida parapsilosis, Aspergillus niger, Penicillium herquei, Cercospora sojina and Cercospora kikuchii. Understanding the mechanism by which SBTX acts on fungi and yeasts may contribute to the design of novel antifungal drugs and/or the development of transgenic plants resistant to pathogens. To this end, the polymorphic yeast C. albicans was chosen as a model organism and changes in the gene expression profile of strain SC5314 upon exposure to SBTX were examined. Genes that were differentially regulated in the presence of SBTX were involved in glucose transport and starvation-associated stress responses as well as in the control of both the induction and repression of C. albicans hyphal formation. Transmission electron microscopy showed that C. albicans cells exposed to SBTX displayed severe signs of starvation and were heavily granulated. Our data were indicative of C. albicans cell starvation despite sufficient nutrient availability in the medium; therefore, it can be speculated that SBTX blocks nutrient uptake systems. Because neither the starvation signal nor the alkaline response pathway lead to the induction of hyphae, we hypothesise that conflicting signals are transmitted to the complex regulatory network controlling morphogenesis, eventually preventing the filamentation signal from reaching a significant threshold. PMID:23894655

  18. Role of auxin-responsive genes in biotic stress responses

    Ghanashyam, Challa; Jain, Mukesh

    2009-01-01

    Although the phytohormone auxin has been implicated primarily in developmental processes, some recent studies suggest its involvement in stress/defense responses as well. Recently, we identified auxin-responsive genes and reported their comprehensive transcript profiling during various stages of development and abiotic stress responses in crop plant rice. The analysis revealed tissue-specific and overlapping expression profiles of auxin-responsive genes during various stages of reproductive d...

  19. Process Control Minitoring by Stress Response

    Hazen, Terry C.; Stahl, David A.

    2006-04-17

    Environmental contamination with a variety of pollutants hasprompted the development of effective bioremediation strategies. But howcan these processes be best monitored and controlled? One avenue underinvestigation is the development of stress response systems as tools foreffective and general process control. Although the microbial stressresponse has been the subject of intensive laboratory investigation, theenvironmental reflection of the laboratory response to specific stresseshas been little explored. However, it is only within an environmentalcontext, in which microorganisms are constantly exposed to multiplechanging environmental stresses, that there will be full understanding ofmicrobial adaptive resiliency. Knowledge of the stress response in theenvironment will facilitate the control of bioremediation and otherprocesses mediated by complex microbial communities.

  20. Stress, stress-induced cortisol responses, and eyewitness identification performance.

    Sauerland, Melanie; Raymaekers, Linsey H C; Otgaar, Henry; Memon, Amina; Waltjen, Thijs T; Nivo, Maud; Slegers, Chiel; Broers, Nick J; Smeets, Tom

    2016-07-01

    In the eyewitness identification literature, stress and arousal at the time of encoding are considered to adversely influence identification performance. This assumption is in contrast with findings from the neurobiology field of learning and memory, showing that stress and stress hormones are critically involved in forming enduring memories. This discrepancy may be related to methodological differences between the two fields of research, such as the tendency for immediate testing or the use of very short (1-2 hours) retention intervals in eyewitness research, while neurobiology studies insert at least 24 hours. Other differences refer to the extent to which stress-responsive systems (i.e., the hypothalamic-pituitary-adrenal axis) are stimulated effectively under laboratory conditions. The aim of the current study was to conduct an experiment that accounts for the contemporary state of knowledge in both fields. In all, 123 participants witnessed a live staged theft while being exposed to a laboratory stressor that reliably elicits autonomic and glucocorticoid stress responses or while performing a control task. Salivary cortisol levels were measured to control for the effectiveness of the stress induction. One week later, participants attempted to identify the thief from target-present and target-absent line-ups. According to regression and receiver operating characteristic analyses, stress did not have robust detrimental effects on identification performance. Copyright © 2016 John Wiley & Sons, Ltd. © 2016 The Authors Behavioral Sciences & the Law Published by John Wiley & Sons Ltd. PMID:27417874

  1. Quinolinic Acid: Neurotoxin or Oxidative Stress Modulator?

    Lenka Kubicova

    2013-10-01

    Full Text Available Quinolinic acid (2,3-pyridinedicarboxylic acid, QUIN is a well-known neurotoxin. Consequently, QUIN could produce reactive oxygen species (ROS. ROS are generated in reactions catalyzed by transition metals, especially iron (Fe. QUIN can form coordination complexes with iron. A combination of differential pulse voltammetry, deoxyribose degradation and Fe(II autoxidation assays was used for explorating ROS formation in redox reactions that are catalyzed by iron in QUIN-Fe complexes. Differential pulse voltammetry showed an anodic shift of the iron redox potential if iron was liganded by QUIN. In the H2O2/FeCl3/ascorbic acid variant of the deoxyribose degradation assay, the dose-response curve was U-shaped. In the FeCl3/ascorbic acid variant, QUIN unambiguously showed antioxidant effects. In the Fe(II autoxidation assay, QUIN decreased the rate of ROS production caused by Fe(II oxidation. Our study confirms that QUIN toxicity may be caused by ROS generation via the Fenton reaction. This, however, applies only for unnaturally high concentrations that were used in attempts to provide support for the neurotoxic effect. In lower concentrations, we show that by liganding iron, QUIN affects the Fe(II/Fe(III ratios that are beneficial to homeostasis. Our results support the notion that redox chemistry can contribute to explaining the hormetic dose-response effects.

  2. Stress Response and Recovery in Atlantic Salmon (Salmo salar L.) Fed Diets Low in the Marine n-3 Fatty Acids EPA and DHA

    Cai, Chan

    2014-01-01

    With the fast growth of today's aquaculture industry, the demand for aquafeeds is expanding dramatically. Finding sustainable alternative sources to fishmeal and fish oil (FO) is becoming an urgent issue; vegetable oil (VO) and plant meal are potential candidates. Replacing the fishmeal and FO with plant materials means fish eat low levels of polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); this may affect the fish growth and health such as s...

  3. Response of Desulfovibrio vulgaris to Alkaline Stress

    Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

    2007-11-30

    The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).

  4. Mycothiol peroxidase MPx protects Corynebacterium glutamicum against acid stress by scavenging ROS

    Tietao Wang

    2015-09-01

    Full Text Available Corynebacterium glutamicum mycothiol peroxidase (MPx is a novel CysGPx family peroxidase that uses both the mycoredoxin and thioredoxin reducing systems as proton donors for peroxide detoxification. In this study, we revealed that MPx is also important for cellular survival under acid stress. A Δmpx mutant exhibited significantly decreased resistance to acid stress and markedly increased accumulation of reactive oxygen species (ROS and protein carbonylation levels in vivo. Overexpression of mpx increased the resistance of C. glutamicum to acid stress by reducing ROS accumulation. Elevated expression of the mpx gene was consistently observed when the C. glutamicum wild-type strain was exposed to acid stress conditions, which in turn directly contributed to tolerance to acid stress. The acid-induced expression of mpx was mediated by the stress-responsive extracytoplasmic function-sigma (ECF-σ factor, SigH. The results unequivocally show that MPx is essential for combating acid stress by reducing intracellular ROS levels induced by acid stress in C. glutamicum, which adds a new dimension to the general physiological functions of CysGPx

  5. Prenatal Stress Enhances Responsiveness to Cocaine

    Kippin, Tod E.; Szumlinski, Karen K.; Kapasova, Zuzana; Rezner, Betsy; See, Ronald E.

    2007-01-01

    Early environmental events have profound influences on a wide range of adult behavior. In the current study, we assessed the influence of maternal stress during gestation on psychostimulant and neurochemical responsiveness to cocaine, cocaine self-administration, and reinstatement of cocaine-seeking in adult offspring. Pregnant, female Sprague–Dawley rats were subjected to either no treatment or to restraint stress three times per day for the last 7 days of gestation and cocaine-related behav...

  6. Neuroendocrine Stress Response after Burn Trauma

    Lindahl, Andreas

    2013-01-01

    Some aspects of the stress response during acute intensive care for severe burns are described and quantified by measuring hormonal and neuroendocrine patterns and relating these to organ function in the short term. This includes an assessment of whether there are markers for the severity of stress that are better than conventional descriptors of the severity of a burn in predicting failing organ function. P-CgA after a major burn injury is an independent and better predictor of organ dysfunc...

  7. Significant year-to-year variation of the response to radiation-induced stress shown by gill fatty acid metabolism in eels (Anguilla anguilla) captured from the wild

    in eels captured in Roskild Fjord in 1972 and 1975, a specifically enhanced synthesis was found from 14C-acetate of 14C-labelled mono-unsaturated fatty acids (C16:1 and C18:1) relative to saturated fatty acids (C16:0 and C18:0) in sea water 4 days after irradiation (10 Gy, 60Co). Corresponding experiments in 1976 and 1982 showed rather the opposite: irradiation resulted in more 14C-labelled saturated fatty acids relative to unsaturated fatty acids, both in fresh and sea water. The latter effect was less marked than that in 1972 and 1975, but still statistically clearly significant. (author)

  8. Phosphatidic acid, a versatile water-stress signal in roots

    Fionn eMcLoughlin

    2013-12-01

    Full Text Available Adequate water supply is of utmost importance for growth and reproduction of plants. In order to cope with water deprivation, plants have to adapt their development and metabolism to ensure survival. To maximize water use efficiency, plants use a large array of signaling mediators such as hormones, protein kinases and phosphatases, Ca2+, reactive oxygen species and low abundant phospholipids that together form complex signaling cascades. Phosphatidic acid (PA is a signaling lipid that rapidly accumulates in response to a wide array of abiotic stress stimuli. PA formation provides the cell with spatial and transient information about the external environment by acting as a protein-docking site in cellular membranes. PA reportedly binds to a number of proteins that play a role during water limiting conditions, such as drought and salinity and has been shown to play an important role in maintaining root system architecture. Members of two osmotic stress-activated protein kinase families, sucrose non-fermenting 1-related protein kinase 2 (SnRK2 and mitogen activated protein kinases (MAPKs were recently shown bind PA and are also involved in the maintenance of root system architecture and salinity stress tolerance. In addition, PA regulates several proteins involved in abscisic acid (ABA-signaling. PA-dependent recruitment of glyceraldehyde-3-phosphate dehydrogenase (GAPDH under water limiting conditions indicates a role in regulating metabolic processes. Finally, a recent study also shows the PA recruits the clathrin heavy chain and a potassium channel subunit, hinting towards additional roles in cellular trafficking and potassium homeostasis. Taken together, the rapidly increasing number of proteins reported to interact with PA implies a broad role for this versatile signaling phospholipid in mediating salt and water stress responses.

  9. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold, and heat

    Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

    2014-01-01

    Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA) is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress cond...

  10. Dysfunctional stress responses in chronic pain.

    Woda, Alain; Picard, Pascale; Dutheil, Frédéric

    2016-09-01

    Many dysfunctional and chronic pain conditions overlap. This review describes the different modes of chronic deregulation of the adaptive response to stress which may be a common factor for these conditions. Several types of dysfunction can be identified within the hypothalamo-pituitary-adrenal axis: basal hypercortisolism, hyper-reactivity, basal hypocortisolism and hypo-reactivity. Neuroactive steroid synthesis is another component of the adaptive response to stress. Dehydroepiandrosterone (DHEA) and its sulfated form DHEA-S, and progesterone and its derivatives are synthetized in cutaneous, nervous, and adipose cells. They are neuroactive factors that act locally. They may have a role in the localization of the symptoms and their levels can vary both in the central nervous system and in the periphery. Persistent changes in neuroactive steroid levels or precursors can induce localized neurodegeneration. The autonomic nervous system is another component of the stress response. Its dysfunction in chronic stress responses can be expressed by decreased basal parasympathethic activity, increased basal sympathetic activity or sympathetic hyporeactivity to a stressful stimulus. The immune and genetic systems also participate. The helper-T cells Th1 secrete pro-inflammatory cytokines such as IL-1-β, IL-2, IL-6, IL-8, IL-12, IFN-γ, and TNF-α, whereas Th2 secrete anti-inflammatory cytokines: IL-4, IL-10, IGF-10, IL-13. Chronic deregulation of the Th1/Th2 balance can occur in favor of anti- or pro-inflammatory direction, locally or systemically. Individual vulnerability to stress can be due to environmental factors but can also be genetically influenced. Genetic polymorphisms and epigenetics are the main keys to understanding the influence of genetics on the response of individuals to constraints. PMID:27262345

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

    Lin Zhou; Hui Xu; Sue Mischke; Meinhardt, Lyndel W.; Dapeng Zhang; Xujun Zhu; Xinghui Li; Wanping Fang

    2014-01-01

    Tea [Camellia sinensis (L.) O. Kuntze] is an important economic crop, and drought is the most important abiotic stress affecting yield and quality. Abscisic acid (ABA) is an important phytohormone responsible for activating drought resistance. Increased understanding of ABA effects on tea plant under drought stress is essential to develop drought-tolerant tea genotypes, along with crop management practices that can mitigate drought stress. The objective of the present investigation is evaluat...

  12. Cloning and characterization of a novel abscisic acid (aba)-induced hva22-like protein from triticum turgidum spp. dicoccoides in response to drought stress

    Doğan, Esen; Dogan, Esen

    2010-01-01

    An HVA22-like protein was found to be differentially expressed in root tissue of wild emmer wheat (Triticum turgidum ssp. dicoccoides), under prolonged drought stress conditions. In this study we were able to clone and characterize the open reading frame of HVA22-like protein from root tissue of wild emmer wheat accession number TR39477, which was previously shown to be a drought-tolerant genotype. Sequence analysis indicated that HVA22-like protein product was a membrane protein and had four...

  13. Two Lactococcus lactis thioredoxin paralogues play different roles in responses to arsenate and oxidative stress

    Efler, Petr; Kilstrup, Mogens; Johnsen, Stig;

    2015-01-01

    Thioredoxin (Trx) maintains intracellular thiol groups in a reduced state and is involved in a wide range of cellular processes, including ribonucleotide reduction, sulphur assimilation, oxidative stress responses and arsenate detoxification. The industrially important lactic acid bacterium...

  14. Polyunsaturated Branched-Chain Fatty Acid Geranylgeranoic Acid Induces Unfolded Protein Response in Human Hepatoma Cells.

    Chieko Iwao

    Full Text Available The acyclic diterpenoid acid geranylgeranoic acid (GGA has been reported to induce autophagic cell death in several human hepatoma-derived cell lines; however, the molecular mechanism for this remains unknown. In the present study, several diterpenoids were examined for ability to induce XBP1 splicing and/or lipotoxicity for human hepatoma cell lines. Here we show that three groups of diterpenoids emerged: 1 GGA, 2,3-dihydro GGA and 9-cis retinoic acid induce cell death and XBP1 splicing; 2 all-trans retinoic acid induces XBP1 splicing but little cell death; and 3 phytanic acid, phytenic acid and geranylgeraniol induce neither cell death nor XBP1 splicing. GGA-induced ER stress/ unfolded protein response (UPR and its lipotoxicity were both blocked by co-treatment with oleic acid. The blocking activity of oleic acid for GGA-induced XBP1 splicing was not attenuated by methylation of oleic acid. These findings strongly suggest that GGA at micromolar concentrations induces the so-called lipid-induced ER stress response/UPR, which is oleate-suppressive, and shows its lipotoxicity in human hepatoma cells.

  15. Influence of omega-3 fatty acid status on the way rats adapt to chronic restraint stress.

    Marie Hennebelle

    Full Text Available Omega-3 fatty acids are important for several neuronal and cognitive functions. Altered omega-3 fatty acid status has been implicated in reduced resistance to stress and mood disorders. We therefore evaluated the effects of repeated restraint stress (6 h/day for 21 days on adult rats fed omega-3 deficient, control or omega-3 enriched diets from conception. We measured body weight, plasma corticosterone and hippocampus glucocorticoid receptors and correlated these data with emotional and depression-like behaviour assessed by their open-field (OF activity, anxiety in the elevated-plus maze (EPM, the sucrose preference test and the startle response. We also determined their plasma and brain membrane lipid profiles by gas chromatography. Repeated restraint stress caused rats fed a control diet to lose weight. Their plasma corticosterone increased and they showed moderate behavioural changes, with increases only in grooming (OF test and entries into the open arms (EPM. Rats fed the omega-3 enriched diet had a lower stress-induced weight loss and plasma corticosterone peak, and reduced grooming. Rats chronically lacking omega-3 fatty acid exhibited an increased startle response, a stress-induced decrease in locomotor activity and exaggerated grooming. The brain omega-3 fatty acids increased as the dietary omega-3 fatty acids increased; diets containing preformed long-chain omega-3 fatty acid were better than diets containing the precursor alpha-linolenic acid. However, the restraint stress reduced the amounts of omega-3 incorporated. These data showed that the response to chronic restraint stress was modulated by the omega-3 fatty acid supply, a dietary deficiency was deleterious while enrichment protecting against stress.

  16. Corporate Responsibility for Systemic Occupational Stress Prevention

    R. Kasperczyk

    2014-09-01

    Full Text Available The purpose of this paper is twofold: to highlight the increased focus on corporate governance responsibility for managing employees’ psychological health, and to present an argument for a systemic approach to prevention of occupational stress. The paper commences with a brief description of the problem posed by occupational stress as a threat to organisational effectiveness. It then discusses the types of currently observed organisational responses to this issue and the extent to which they are shaped by beliefs about occupational stress. There are two fundamental approaches to dealing with work stress, one aimed at the individual and the other, at the organisation. The more comprehensive approaches have been increasingly reported to be more effective. The argument for a systemic approach to its prevention is then developed, in line with the risk management framework currently being adopted by Government jurisdictions governing Occupational Health and Safety in Australia and New Zealand. As the stress issue is now couched in health and safety terms, it is a moral and legal duty of the Board to satisfy itself that it is effectively addressed.

  17. Transcriptome Analysis of Enterococcus faecalis in Response to Alkaline Stress

    Ran eshujun

    2015-08-01

    Full Text Available E. faecalis is the most commonly isolated species from endodontic failure root canals; its persistence in treated root canals has been attributed to its ability to resist high pH stress. The goal of this study was to characterize the E. faecalis transcriptome and to identify candidate genes for response and resistance to alkaline stress using Illumina HiSeq 2000 sequencing.We found that E. faecalis could survive and form biofilms in a pH 10 environment and that alkaline stress had a great impact on the transcription of many genes in the E. faecalis genome. The transcriptome sequencing results revealed that 613 genes were differentially expressed (DEGs for E. faecalis grown in pH 10 medium; 211 genes were found to be differentially up-regulated and 402 genes differentially down-regulated. Many of the down-regulated genes found are involved in cell energy production and metabolism and carbohydrate and amino acid metabolism, and the up-regulated genes are mostly related to nucleotide transport and metabolism. The results presented here reveal that cultivation of E. faecalis in alkaline stress has a profound impact on its transcriptome. The observed regulation of genes and pathways revealed that E. faecalis reduced its carbohydrate and amino acid metabolism and increased nucleotide synthesis to adapt and grow in alkaline stress. A number of the regulated genes may be useful candidates for the development of new therapeutic approaches for the treatment of E. faecalis infections.

  18. Simultaneous determination of shikimic acid, salicylic acid and jasmonic acid in wild and transgenic Nicotiana langsdorffii plants exposed to abiotic stresses.

    Scalabrin, Elisa; Radaelli, Marta; Capodaglio, Gabriele

    2016-06-01

    The presence and relative concentration of phytohormones may be regarded as a good indicator of an organism's physiological state. The integration of the rolC gene from Agrobacterium rhizogenes and of the rat glucocorticoid receptor (gr) in Nicotiana langsdorffii Weinmann plants has shown to determine various physiological and metabolic effects. The analysis of wild and transgenic N. langsdorffii plants, exposed to different abiotic stresses (high temperature, water deficit, and high chromium concentrations) was conducted, in order to investigate the metabolic effects of the inserted genes in response to the applied stresses. The development of a new analytical procedure was necessary, in order to assure the simultaneous determination of analytes and to obtain an adequately low limit of quantification. For the first time, a sensitive HPLC-HRMS quantitative method for the simultaneous determination of salicylic acid, jasmonic acid and shikimic acid was developed and validated. The method was applied to 80 plant samples, permitting the evaluation of plant stress responses and highlighting some metabolic mechanisms. Salicylic, jasmonic and shikimic acids proved to be suitable for the comprehension of plant stress responses. Chemical and heat stresses showed to induce the highest changes in plant hormonal status, differently affecting plant response. The potential of each genetic modification toward the applied stresses was marked and particularly the resistance of the gr modified plants was evidenced. This work provides new information in the study of N. langsdorffii and transgenic organisms, which could be useful for the further application of these transgenes. PMID:26966898

  19. Arabidopsis YAK1 regulates abscisic acid response and drought resistance.

    Kim, Dongjin; Ntui, Valentine Otang; Xiong, Liming

    2016-07-01

    Abscisic acid (ABA) is an important phytohormone that controls several plant processes such as seed germination, seedling growth, and abiotic stress response. Here, we report that AtYak1 plays an important role in ABA signaling and postgermination growth in Arabidopsis. AtYak1 knockout mutant plants were hyposensitive to ABA inhibition of seed germination, cotyledon greening, seedling growth, and stomatal movement. atyak1-1 mutant plants display reduced drought stress resistance, as evidenced by water loss rate and survival rate. Molecular genetic analysis revealed that AtYak1 deficiency led to elevated expression of stomatal-related gene, MYB60, and down-regulation of several stress-responsive genes. Altogether, these results indicate that AtYak1 plays a role as a positive regulator in ABA-mediated drought response in Arabidopsis. PMID:27264339

  20. Regulated cell death and adaptive stress responses.

    Galluzzi, Lorenzo; Bravo-San Pedro, José Manuel; Kepp, Oliver; Kroemer, Guido

    2016-06-01

    Eukaryotic cells react to potentially dangerous perturbations of the intracellular or extracellular microenvironment by activating rapid (transcription-independent) mechanisms that attempt to restore homeostasis. If such perturbations persist, cells may still try to cope with stress by activating delayed and robust (transcription-dependent) adaptive systems, or they may actively engage in cellular suicide. This regulated form of cell death can manifest with various morphological, biochemical and immunological correlates, and constitutes an ultimate attempt of stressed cells to maintain organismal homeostasis. Here, we dissect the general organization of adaptive cellular responses to stress, their intimate connection with regulated cell death, and how the latter operates for the preservation of organismal homeostasis. PMID:27048813

  1. Transcriptome Analysis of High-Temperature Stress in Developing Barley Caryopses :Early Stress Responses and Effects on Storage Compound Biosynthesis

    Elke Mangelsen; Joachim Kilian; Klaus Harter; Christer Jansson; Dierk Wanke; Eva Sundberg

    2011-01-01

    High-temperature stress,like any abiotic stress,impairs the physiology and development of plants,including the stages of seed setting and ripening.We used the Aflymetrix 22K Barley1 GeneChip microarray to investigate the response of developing barley(Hordeum vulgare)seeds,termed caryopses,after 0.5,3,and 6 h of heat stress exposure;958 induced and 1122 repressed genes exhibited spatial and temporal expression patterns that provide a detailed insight into the caryopses'early heat stress responses.Down-regulation of genes related to storage compound biosynthesis and cell growth provides evidence for a rapid impairment of the caryopsis' development.Increased levels of sugars and amino acids were indicative for both production of compatible solutes and feedback-induced accumulation of substrates for storage compound biosynthesis.Metadata analysis identified embryo and endosperm as primary locations of heat stress responses,indicating a strong impact of short-term heat stress on central developmental functions of the caryopsis.A comparison with heat stress responses in Arabidopsis shoots and drought stress responses in barley caryopses identified both conserved and presumably heat-and caryopsis-specific stress-responsive genes.Summarized,our data provide an important basis for further investigation of gene functions in order to aid an improved heat tolerance and reduced losses of yield in barley as a model for cereal crops.

  2. The herbicide 2,4-dichlorophenoxyacetic acid induces the generation of free-radicals and associated oxidative stress responses in yeast

    The pro-oxidant action of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is demonstrated in this study using Saccharomyces cerevisiae as a eukaryotic experimental model. Evidence is presented for the generation of hydroxyl-radicals, in yeast cells suddenly exposed to 2,4-D, detected by in vivo electron paramagnetic resonance (EPR) spectroscopy using 5,5'-dimethyl-1-pyrroline N-oxide and 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide as spin-traps. The intensity of the EPR spectra was dependent on the concentration of herbicide tested and was consistently higher in a mutant (Δsod1) devoid of the cytosolic CuZn-superoxide dismutase. A time-course-dependent variation of the level of free-radical adducts was registered upon sudden exposure of an yeast cell population to concentrations of 2,4-D that lead to an initial period of viability loss, before resumption of inhibited growth by the viable adapted population. The variation pattern of the level of hydroxyl-radical adducts correlated with the one determined for the activity of Sod1p, cytosolic catalase Ctt1p, and the dithiol glutaredoxins Grx1p and Grx2p

  3. Physiological Responses to Thermal Stress and Exercise

    Iyota, Hiroyuki; Ohya, Akira; Yamagata, Junko; Suzuki, Takashi; Miyagawa, Toshiaki; Kawabata, Takashi

    The simple and noninvasive measuring methods of bioinstrumentation in humans is required for optimization of air conditioning and management of thermal environments, taking into consideration the individual specificity of the human body as well as the stress conditions affecting each. Changes in human blood circulation were induced with environmental factors such as heat, cold, exercise, mental stress, and so on. In this study, the physiological responses of human body to heat stress and exercise were investigated in the initial phase of the developmental research. We measured the body core and skin temperatures, skin blood flow, and pulse wave as the indices of the adaptation of the cardiovascular system. A laser Doppler skin blood flowmetry using an optical-sensor with a small portable data logger was employed for the measurement. These results reveal the heat-stress and exercise-induced circulatory responses, which are under the control of the sympathetic nerve system. Furthermore, it was suggested that the activity of the sympathetic nervous system could be evaluated from the signals of the pulse wave included in the signals derived from skin blood flow by means of heart rate variability assessments and detecting peak heights of velocity-plethysmogram.

  4. Stressed out? Associations between perceived and physiological stress responses in adolescents: The TRAILS study

    Oldehinkel, Albertine J.; Ormel, Johan; Bosch, Nienke M.; Bouma, Esther M. C.; Van Roon, Arie M.; Rosmalen, Judith G. M.; Riese, Harriette

    2011-01-01

    Studies regarding the interrelation of perceived and physiological stress indices have shown diverging results. Using a population sample of adolescents (N=715, 50.9% girls, mean age 16.11 years, SD=0.59), we tested three hypotheses: (1) perceived responses during social stress covary with concurrent physiological stress responses; (2) high pretest levels of perceived stress predict large physiological responses; and (3) large physiological responses to social stress predict low posttest perc...

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

    Wang, Zhenyu

    2011-05-01

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

  6. Lipid signalling in plant responses to abiotic stress.

    Hou, Quancan; Ufer, Guido; Bartels, Dorothea

    2016-05-01

    Lipids are one of the major components of biological membranes including the plasma membrane, which is the interface between the cell and the environment. It has become clear that membrane lipids also serve as substrates for the generation of numerous signalling lipids such as phosphatidic acid, phosphoinositides, sphingolipids, lysophospholipids, oxylipins, N-acylethanolamines, free fatty acids and others. The enzymatic production and metabolism of these signalling molecules are tightly regulated and can rapidly be activated upon abiotic stress signals. Abiotic stress like water deficit and temperature stress triggers lipid-dependent signalling cascades, which control the expression of gene clusters and activate plant adaptation processes. Signalling lipids are able to recruit protein targets transiently to the membrane and thus affect conformation and activity of intracellular proteins and metabolites. In plants, knowledge is still scarce of lipid signalling targets and their physiological consequences. This review focuses on the generation of signalling lipids and their involvement in response to abiotic stress. We describe lipid-binding proteins in the context of changing environmental conditions and compare different approaches to determine lipid-protein interactions, crucial for deciphering the signalling cascades. PMID:26510494

  7. Neural and cardiovascular responses to emotional stress in humans

    Carter, Jason R.; Durocher, John J.; Kern, Rosalie P.

    2008-01-01

    Sympathetic neural responses to mental stress are well documented but controversial, whereas sympathetic neural responses to emotional stress are unknown. The purpose of this study was to investigate neural and cardiovascular responses to emotional stress evoked by negative pictures and reexamine the relationship between muscle sympathetic nerve activity (MSNA) and perceived stress. Mean arterial pressure (MAP), heart rate (HR), MSNA, and perceived stress levels were recorded in 18 men during...

  8. Adaptive Acid Tolerance Response of Streptococcus sobrinus

    Nascimento, Marcelle M.; Lemos, José A. C.; Abranches, Jacqueline; Gonçalves, Reginaldo B.; Burne, Robert A.

    2004-01-01

    Streptococcus mutans and Streptococcus sobrinus are the bacteria most commonly associated with human dental caries. A major virulence attribute of these and other cariogenic bacteria is acid tolerance. The acid tolerance mechanisms of S. mutans have begun to be investigated in detail, including the adaptive acid tolerance response (ATR), but this is not the case for S. sobrinus. An analysis of the ATR of two S. sobrinus strains was conducted with cells grown to steady state in continuous chem...

  9. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold and heat

    Kazuo eNakashima

    2014-05-01

    Full Text Available Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress conditions, and the ABA-responsive element (ABRE is the major cis-element for ABA-responsive gene expression. Transcription factors (TFs are master regulators of gene expression. ABRE-binding protein (AREB and ABRE-binding factor (ABF TFs control gene expression in an ABA-dependent manner. SNF1-related protein kinases 2, group A 2C-type protein phosphatases, and ABA receptors were shown to control the ABA signaling pathway. ABA-independent signaling pathways such as dehydration-responsive element-binding protein (DREB TFs and NAC TFs are also involved in stress responses including drought, heat and cold. Recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress responses. The important roles of these transcription factors in crosstalk among abiotic stress responses will be discussed. Control of ABA or stress signaling factor expression can improve tolerance to environmental stresses. Recent studies using crops have shown that stress-specific overexpression of TFs improves drought tolerance and grain yield compared with controls in the field.

  10. Immune responses to stress after stress management training in patients with rheumatoid arthritis

    de Brouwer, Sabine JM; van Middendorp, Henriët; Kraaimaat, Floris W.; Radstake, Timothy RDJ; Joosten, Irma; Donders, A Rogier T; Eijsbouts, Agnes; Koulil, Saskia Spillekom-van; van Riel, Piet LCM; Evers, Andrea WM

    2013-01-01

    Introduction Psychological stress may alter immune function by activating physiological stress pathways. Building on our previous study, in which we report that stress management training led to an altered self-reported and cortisol response to psychological stress in patients with rheumatoid arthritis (RA), we explored the effects of this stress management intervention on the immune response to a psychological stress task in patients with RA. Methods In this study, 74 patients with RA, who w...

  11. Chronic intermittent psychological stress promotes macrophage reverse cholesterol transport by impairing bile acid absorption in mice.

    Silvennoinen, Reija; Quesada, Helena; Kareinen, Ilona; Julve, Josep; Kaipiainen, Leena; Gylling, Helena; Blanco-Vaca, Francisco; Escola-Gil, Joan Carles; Kovanen, Petri T; Lee-Rueckert, Miriam

    2015-05-11

    Psychological stress is a risk factor for atherosclerosis, yet the pathophysiological mechanisms involved remain elusive. The transfer of cholesterol from macrophage foam cells to liver and feces (the macrophage-specific reverse cholesterol transport, m-RCT) is an important antiatherogenic pathway. Because exposure of mice to physical restraint, a model of psychological stress, increases serum levels of corticosterone, and as bile acid homeostasis is disrupted in glucocorticoid-treated animals, we investigated if chronic intermittent restraint stress would modify m-RCT by altering the enterohepatic circulation of bile acids. C57Bl/6J mice exposed to intermittent stress for 5 days exhibited increased transit through the large intestine and enhanced fecal bile acid excretion. Of the transcription factors and transporters that regulate bile acid homeostasis, the mRNA expression levels of the hepatic farnesoid X receptor (FXR), the bile salt export pump (BSEP), and the intestinal fibroblast growth factor 15 (FGF15) were reduced, whereas those of the ileal apical sodium-dependent bile acid transporter (ASBT), responsible for active bile acid absorption, remained unchanged. Neither did the hepatic expression of cholesterol 7α-hydroxylase (CYP7A1), the key enzyme regulating bile acid synthesis, change in the stressed mice. Evaluation of the functionality of the m-RCT pathway revealed increased fecal excretion of bile acids that had been synthesized from macrophage-derived cholesterol. Overall, our study reveals that chronic intermittent stress in mice accelerates m-RCT specifically by increasing fecal excretion of bile acids. This novel mechanism of m-RCT induction could have antiatherogenic potential under conditions of chronic stress. PMID:25969465

  12. The early stress responses in fish larvae.

    Pederzoli, Aurora; Mola, Lucrezia

    2016-05-01

    During the life cycle of fish the larval stages are the most interesting and variable. Teleost larvae undergo a daily increase in adaptability and many organs differentiate and become active. These processes are concerted and require an early neuro-immune-endocrine integration. In larvae communication among the nervous, endocrine and immune systems utilizes several known signal molecule families which could be different from those of the adult fish. The immune-neuroendocrine system was studied in several fish species, among which in particular the sea bass (Dicentrarchus labrax), that is a species of great commercial interest, very important in aquaculture and thus highly studied. Indeed the immune system of this species is the best known among marine teleosts. In this review the data on main signal molecules of stress carried out on larvae of fish are considered and discussed. For sea bass active roles in the early immunological responses of some well-known molecules involved in the stress, such as ACTH, nitric oxide, CRF, HSP-70 and cortisol have been proposed. These molecules and/or their receptors are biologically active mainly in the gut before complete differentiation of gut-associated lymphoid tissue (GALT), probably acting in an autocrine/paracrine way. An intriguing idea emerges from all results of these researches; the molecules involved in stress responses, expressed in the adult cells of the hypothalamic-pituitary axis, during the larval life of fish are present in several other localizations, where they perform probably the same role. It may be hypothesized that the functions performed by hypothalamic-pituitary system are particularly important for the survival of the larva and therefore they comprises several other localizations of body. Indeed the larval stages of fish are very crucial phases that include many physiological changes and several possible stress both internal and environmental. PMID:26968620

  13. Cannibalism stress response in Bacillus subtilis.

    Höfler, Carolin; Heckmann, Judith; Fritsch, Anne; Popp, Philipp; Gebhard, Susanne; Fritz, Georg; Mascher, Thorsten

    2016-01-01

    When faced with carbon source limitation, the Gram-positive soil organism Bacillus subtilis initiates a survival strategy called sporulation, which leads to the formation of highly resistant endospores that allow B. subtilis to survive even long periods of starvation. In order to avoid commitment to this energy-demanding and irreversible process, B. subtilis employs another strategy called 'cannibalism' to delay sporulation as long as possible. Cannibalism involves the production and secretion of two cannibalism toxins, sporulation delaying protein (SDP) and sporulation killing factor (SKF), which are able to lyse sensitive siblings. The lysed cells are thought to then provide nutrients for the cannibals to slow down or even prevent them from entering sporulation. In this study, we uncovered the role of the cell envelope stress response (CESR), especially the Bce-like antimicrobial peptide detoxification modules, in the cannibalism stress response during the stationary phase. SDP and SKF specifically induce Bce-like systems and some extracytoplasmic function σ factors in stationary-phase cultures, but only the latter provide some degree of protection. A full Bce response is only triggered by mature toxins, and not by toxin precursors. Our study provides insights into the close relationship between stationary-phase survival and the CESR of B. subtilis. PMID:26364265

  14. [Metabolic response to trauma and stress].

    Omerbegović, Meldijana; Durić, Amira; Muratović, Nusreta; Mulalić, Lejla; Hamzanija, Emina

    2003-01-01

    Trauma, surgery, burns and infection are accompanied with catabolic response which is characterized by enhanced protelysis, enhanced excretion of nitrogen, neoglucogenesis and resistance of peripheral tissues to insulin. This catabolic response is mediated through neural pathways and neuroendocrine axis. The purpose of this response is restoration of adequate perfusion and oxygenation and releasing of energy and substrates for the tissues, organs and systems which functions are essential for the survival. Metabolic response to injury and severe infection leads to decomposition of skeletal muscle proteins to amino acids, intensive liver gluconcogenesis from lactate, glycerol and alanin with enhanced oxidation of aminoacids. These substrates are necessary for synthesis of various mediators of protein or lipid nature, which are important for the defense and tissue regeneration. The changes result in negative balance of nitrogen, loss of body weight, and lower plasma concentration of all aminoacids. Patients who were unable to develop this hypercatabolic response have poor prognosis, and the patients with hypercatabolic response rapidly lose their body cell mass and without metabolic and nutritive support have more complications and higher mortality. Although neoglucogenesis, proteolysis and lipolysis are resistant to exogenous nutrients, metabolic support in critical illness improves the chances for survival until the healing of the disease. Casual therapy in such conditions is elimination of "stressors" which maintain abnormal endocrine and metabolic response. Adequate oxygenation, hemostasis, infection control and control of extracellular compartment expansion and low flows, are essential for the efficacy of nutritive support and that is the only way to convalescence and wound healing. PMID:15017867

  15. Acid stress adaptation protects saccharomyces cerevisiae from acetic acid-induced programme cell death

    Giannattasio, Sergio; Guaragnella, Nicoletta; Côrte-Real, Manuela; Passarella, Salvatore; Marra, Ersilia

    2005-01-01

    In this work evidence is presented that acid stress adaptation protects Saccharomyces cerevisiae from acetic acid-mediated programmed cell death. Exponential-phase yeast cells, non-adapted or adapted to acid stress by 30 min incubation in rich medium set at pH 3.0 with HCl, have been exposed to increasing concentrations of acetic acid and time course changes of cell viability have been assessed. Adapted cells, in contrast to non-adapted cells, when exposed to 80 mM acetic acid for 200 min ...

  16. Tomato NAC transcription factor SlSRN1 positively regulates defense response against biotic stress but negatively regulates abiotic stress response.

    Bo Liu

    Full Text Available Biotic and abiotic stresses are major unfavorable factors that affect crop productivity worldwide. NAC proteins comprise a large family of transcription factors that play important roles in plant growth and development as well as in responses to biotic and abiotic stresses. In a virus-induced gene silencing-based screening to identify genes that are involved in defense response against Botrytis cinerea, we identified a tomato NAC gene SlSRN1 (Solanum lycopersicum Stress-related NAC1. SlSRN1 is a plasma membrane-localized protein with transactivation activity in yeast. Expression of SlSRN1 was significantly induced by infection with B. cinerea or Pseudomonas syringae pv. tomato (Pst DC3000, leading to 6-8 folds higher than that in the mock-inoculated plants. Expression of SlSRN1 was also induced by salicylic acid, jasmonic acid and 1-amino cyclopropane-1-carboxylic acid and by drought stress. Silencing of SlSRN1 resulted in increased severity of diseases caused by B. cinerea and Pst DC3000. However, silencing of SlSRN1 resulted in increased tolerance against oxidative and drought stresses. Furthermore, silencing of SlSRN1 accelerated accumulation of reactive oxygen species but attenuated expression of defense genes after infection by B. cinerea. Our results demonstrate that SlSRN1 is a positive regulator of defense response against B. cinerea and Pst DC3000 but is a negative regulator for oxidative and drought stress response in tomato.

  17. Avaliação de genótipos de aveia branca sob estresse de ácidos orgânicos Responses of white oat genotypes to stresses of organic acids

    Mauricio Marini Kopp

    2009-01-01

    Full Text Available A ocorrência de condições anaeróbias nos solos hidromórficos, associada com a presença de matéria orgânica favorece o desenvolvimento de microrganismos anaeróbios que produzem substâncias fitotóxicas, principalmente ácidos orgânicos de cadeia curta. O objetivo do trabalho foi avaliar a resposta de 20 genótipos de aveia (Avena sativa L. aos ácidos acético, propiônico e butírico. O trabalho foi executado em sistema de hidroponia com três doses (0; 3 e 6 mM da mistura dos três ácidos na relação 6:3:1 respectivamente. O delineamento utilizado foi em blocos casualizados com três repetições em esquema fatorial. As variáveis mensuradas foram: comprimento de raízes (CR e parte aérea (CPA, número de raízes (NR e matéria seca de raízes (MSR e parte aérea (MSPA. Foram procedidas análise de variância e ajustes de regressão. Os efeitos de interação entre doses x genótipos para as variáveis CR e MSR revelaram significância e as regressões estabelecidas para estas variáveis, revelaram dois genótipos com estabilidade de crescimento radicular (OR-3 e FAPA-5 e três com estabilidade de acúmulo de matéria seca (OR-3, UFRGS-17 e UPF-15 frente ao estresse por ácidos orgânicos. A caracterização destes genótipos à ação fitotóxica dos ácidos orgânicos é importante fonte de recursos aos programas de melhoramento genético que visem obter genótipos com elevada capacidade produtiva, em solos de várzea do Sul do Brasil sob plantio direto ou cultivo mínimo.The association of anaerobic conditions with high organic matter content in hydromorphic soils favors the development of anaerobic microorganisms that produce phytotoxic substances, especially short chain organic acids. The objective of this investigation was to evaluate the response of 20 oat (Avena sativa L. genotypes to the exposure of acetic, propionic and butyric acids in hydroponic system. Three doses (0; 3 and 6 mM of a mixture of the three acids at a 6

  18. Ascorbate and dehydroascorbic acid as reliable biomarkers of oxidative stress

    Lykkesfeldt, Jens

    2007-01-01

    Lack of post-sampling stability of ascorbate and dehydroascorbic acid and failure to block their in vivo equilibrium have lowered their value as biomarkers of oxidative stress and limited the ability to further investigate their possible role in disease prevention. In the present paper, the...... analytical reproducibility was tested by repeated analysis of plasma aliquots from one individual over four years. The plasma was subjected to acidic deproteinization with an equal volume of 10% meta-phosphoric acid containing 2 mM EDTA and analyzed for ascorbate and dehydroascorbic acid by high-performance...

  19. Job stress factors, stress response, and social support in association with insomnia of Japanese male workers.

    Nishitani, Naoko; Sakakibara, Hisataka

    2010-01-01

    The aim of the present study was to examine the relation of insomnia with job stress factors, stress response, and social support. A self-completed questionnaire survey was conducted in 212 male Japanese workers at a synthetic fiber plant. With regard to insomnia, subjects were asked the first 5 of the 8 questions on the Athens Insomnia Scale (AIS). Job stress factors, stress response and social support were assessed using the Job Stress Questionnaire. Multiple regression analyses showed that psychological job stress factors of poor appropriateness of work and high qualitative workload were associated with insomnia. The psychological stress response of depression and physical stress responses were also related with insomnia. Depression was also related to appropriateness of work. The present results showed that insomnia was closely related with the psychological job stress factor of appropriateness of work and the psychological response of depression. These mutual relationships between insomnia and poor mental health need be investigated further. PMID:20424348

  20. Hydration state controls stress responsiveness and social behavior

    Krause, Eric G.; de Kloet, Annette D.; Flak, Jonathan N.; Smeltzer, Michael D.; Solomon, Matia B.; Evanson, Nathan K.; Woods, Stephen C; Sakai, Randall R.; Herman, James P.

    2011-01-01

    Life stress frequently occurs within the context of homeostatic challenge, requiring integration of physiological and psychological need into appropriate hormonal, cardiovascular and behavioral responses. To test neural mechanisms underlying stress integration within the context of homeostatic adversity, we evaluated the impact of a pronounced physiological (hypernatremia) challenge on hypothalamic-pituitary-adrenal (HPA), cardiovascular and behavioral responses to an acute psychogenic stress...

  1. What is stress?: dose-response effects in commonly used in vitro stress assays

    Claeys, Hannes; Van Landeghem, Sofie; Dubois, Marieke; Maleux, Katrien; Inzé, Dirk

    2014-01-01

    In vitro stress assays are commonly used to study the responses of plants to abiotic stress and to assess stress tolerance. A literature review reveals that most studies use very high stress levels and measure criteria such as germination, plant survival, or the development of visual symptoms such as bleaching. However, we show that these parameters are indicators of very severe stress, and such studies thus only provide incomplete information about stress sensitivity in Arabidopsis (Arabidop...

  2. Psychophysiological responses to stress after stress management training in patients with rheumatoid arthritis.

    de Brouwer, Sabine J. M.; Kraaimaat, Floris W.; Sweep, Fred C. G. J.; Donders, Rogier T.; Agnes Eijsbouts; Saskia van Koulil; van Riel, Piet L C M; Evers, Andrea W. M.

    2011-01-01

    BACKGROUND: Stress management interventions may prove useful in preventing the detrimental effects of stress on health. This study assessed the effects of a stress management intervention on the psychophysiological response to stress in patients with rheumatoid arthritis (RA). METHODS: Seventy-four patients with RA, who were randomly assigned to either a control group or a group that received short-term stress management training, performed a standardized psychosocial stress task (Trier Socia...

  3. Physiological and molecular responses to drought in Petunia: the importance of stress severity

    Kim, Jongyun; Malladi, Anish; van Iersel, Marc W.

    2012-01-01

    Plant responses to drought stress vary depending on the severity of stress and the stage of drought progression. To improve the understanding of such responses, the leaf physiology, abscisic acid (ABA) concentration, and expression of genes associated with ABA metabolism and signalling were investigated in Petunia × hybrida. Plants were exposed to different specific substrate water contents (θ = 0.10, 0.20, 0.30, or 0.40 m3·m–3) to induce varying levels of drought stress. Plant responses were...

  4. Understanding the responses of rice to environmental stress using proteomics.

    Singh, Raksha; Jwa, Nam-Soo

    2013-11-01

    Diverse abiotic and biotic stresses have marked effects on plant growth and productivity. To combat such stresses, plants have evolved complex but not well understood responses. Common effects upon perception of environmental stress are differential expression of the plant proteome and the synthesis of novel regulatory proteins for protection from and acclimation to stress conditions. Plants respond differently in terms of activation of stress-responsive signaling pathways depending upon the type and nature of the stresses to which they are exposed. Progress in proteomics and systems biology approaches has made it possible to identify the novel proteins and their interactions that function in abiotic stress responses. This will enable elucidation of the functions of individual proteins and their roles in signaling networks. Proteomic analysis of the responses to various stress conditions is performed most commonly using 2D gel electrophoresis and high-throughput identification by LC-MS/MS. Because of recent developments in proteomics techniques, numerous proteomics studies of rice under abiotic stress conditions have been performed. In this review, proteomics studies addressing rice responses to the major environmental stresses--including cold, heat, drought, salt, heavy metals, minerals, UV radiation, and ozone--are discussed. Unique or common protein responses to these stress conditions are summarized and interpreted according to their possible physiological responses in each stress. Additionally, proteomics studies on various plant systems under various abiotic stress conditions are compared to provide deeper understanding of specific and common proteome responses in rice and other plant systems, which will further contribute to the identification of abiotic stress tolerance factor at protein level. Functional analysis of stress-responsive proteins will provide new research objectives with the aim of achieving stable crop productivity in the face of the

  5. Stress Granule-Defective Mutants Deregulate Stress Responsive Transcripts

    Yang, Xiaoxue; Shen, Yi; Garre, Elena; Hao, Xinxin; Krumlinde, Daniel; Cvijović, Marija; Arens, Christina; Nyström, Thomas; Liu, Beidong; Sunnerhagen, Per

    2014-01-01

    To reduce expression of gene products not required under stress conditions, eukaryotic cells form large and complex cytoplasmic aggregates of RNA and proteins (stress granules; SGs), where transcripts are kept translationally inert. The overall composition of SGs, as well as their assembly requirements and regulation through stress-activated signaling pathways remain largely unknown. We have performed a genome-wide screen of S. cerevisiae gene deletion mutants for defects in SG formation upon...

  6. Salicylic acid alleviates cold-induced photosynthesis inhibition and oxidative stress in Jasminum sambac

    CAI, HAN; He, Mengying; Ma, Kun; HUANG, YONGGAO; Wang, Yun

    2015-01-01

    Salicylic acid (SA) is a signal molecule that mediates many biotic and abiotic stress-induced physiological responses in plants. In the current study the protective effects of SA on cold stress-caused oxidative damage and photosynthesis inhibition in jasmine plants (Jasminum sambac) were examined. Jasmine seedlings were pretreated with 100 µM SA for 3 days and then subjected to cold stress (4 °C) for 15 days. The amounts of superoxide radicals (O_2^{-}) and hydrogen peroxide (H_{2}O_{2}) sign...

  7. Laboratory stress corrosion cracking studies with sulfur acids and chlorides

    Baylor, V.B.

    1985-10-01

    Stress corrosion cracking (SCC) caused by polythionic acid and/or chlorides has occurred in coal liquefaction pilot plants. This problem is also common in refineries and has been extensively researched. This study examines: (1) the relationship of the ASTM standard ferric sulfate-sulfuric acid test for determining sensitization to resistance to polythionic SCC; (2) the cracking resistance of higher-alloy. Fe-Ni-Cr materials and common austenitic stainless steels (SS); and (3) the effect of chloride concentrations up to 1% in polythionic acid solutions on cracking behavior. The ferric sulfatesulfuric acid test can be used as an acceptance test for materials resistant to polythionic acid SCC. More highly alloyed materials were more resistant to sensitization than most austenitic SS and were virtually unattacked in polythionic acid solutions containing up to 1% chloride. Chloride increased the corrosion rate and caused localized pitting but it did not significantly affect the number of failures or the failure mode.

  8. Biological Stress Response Terminology: Integrating the Concepts of Adaptive Response and Preconditioning Stress Within a Hormetic Dose-Response Framework

    Many biological subdisciplines that regularly assess dose-response relationships have identified an evolutionarily conserved process in which a low dose of a stressful stimulus activates an adaptive response that increases the resistance of the cell or organism to a moderate to severe level of stres...

  9. Epigenetic regulation of stress responses in plants

    Chinnusamy, Viswanathan; Zhu, Jian-Kang

    2009-01-01

    Gene expression driven by developmental and stress cues often depends on nucleosome histone post-translational modifications and sometimes on DNA methylation. A number of studies have shown that these DNA and histone modifications play a key role in gene expression and plant development under stress. Most of these stress-induced modifications are reset to the basal level once the stress is relieved, while some of the modifications may be stable, that is, may be carried forward as ‘stress memo...

  10. Laboratory stress corrosion cracking studies in polythionic acid

    Baylor, V.B.; Newsome, J.F.

    1984-08-01

    Stress corrosion cracking caused by polythionic acid and/or chlorides is a problem in coal liquefaction pilot plants. This problem is also common in refineries and has been the subject of extensive research. This study examines (1) the relationship of the ASTM standard ferric sulfate-sulfuric acid test for determining sensitization to resistance to polythionic stress corrosion cracking, (2) the cracking resistance of higher-alloy Fe-Ni-Cr materials in addition to the common austenitic stainless steels, and (3) the effect of chloride concentrations up to 1% in polythionic acid solutions on cracking behavior. We found that the ferric sulfate-sulfuric acid test can be used as an acceptance test for materials resistant to polythionic acid stress corrosion cracking because of its severity. The more highly alloyed materials were more resistant to sensitization than most of the austenitic stainless steels and were virtually unattacked in polythionic acid solutions containing up to 1% chloride. Chloride increased the corrosion rate and caused localized pitting, but it did not affect significantly the number of failures or the failure mode.

  11. Biotechnological Approaches to Study Plant Responses to Stress

    Pérez-Clemente, Rosa M; Vicente Vives; Zandalinas, Sara I.; López-Climent, María F.; Valeria Muñoz; Aurelio Gómez-Cadenas

    2013-01-01

    Multiple biotic and abiotic environmental stress factors affect negatively various aspects of plant growth, development, and crop productivity. Plants, as sessile organisms, have developed, in the course of their evolution, efficient strategies of response to avoid, tolerate, or adapt to different types of stress situations. The diverse stress factors that plants have to face often activate similar cell signaling pathways and cellular responses, such as the production of stress proteins, upre...

  12. Protective effects of gallic acid against spinal cord injury-induced oxidative stress.

    Yang, Yong Hong; Wang, Zao; Zheng, Jie; Wang, Ran

    2015-08-01

    The present study aimed to investigate the role of gallic acid in oxidative stress induced during spinal cord injury (SCI). In order to measure oxidative stress, the levels of lipid peroxide, protein carbonyl, reactive oxygen species and nitrates/nitrites were determined. In addition, the antioxidant status during SCI injury and the protective role of gallic acid were investigated by determining glutathione levels as well as the activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase. Adenosine triphophatase (ATPase) enzyme activities were determined to evaluate the role of gallic acid in SCI-induced deregulation of the activity of enzymes involved in ion homeostasis. The levels of inflammatory markers such as nuclear factor (NF)-κB and cycloxygenase (COX)-2 were determined by western blot analysis. Treatment with gallic acid was observed to significantly mitigate SCI-induced oxidative stress and the inflammatory response by reducing the oxidative stress, decreasing the expression of NF-κB and COX-2 as well as increasing the antioxidant status of cells. In addition, gallic acid modulated the activity of ATPase enzymes. Thus the present study indicated that gallic acid may have a role as a potent antioxidant and anti-inflammatory agent against SCI. PMID:25955644

  13. Overexpression of a cytosolic abiotic stress responsive universal stress protein (SbUSP mitigates salt and osmotic stress in transgenic tobacco plants

    Pushpika eUdawat

    2016-04-01

    Full Text Available The Universal Stress Protein (USP is a ubiquitous protein and plays an indispensable role in plant abiotic stress tolerance. The genome of Salicornia brachiata contains two homologues of intron less SbUSP gene which encodes for salt and osmotic responsive universal stress protein. In vivo localization reveals that SbUSP is a membrane bound cytosolic protein. The role of the gene was functionally validated by developing transgenic tobacco and compared with control (wild type and vector control plants under different abiotic stress condition. Transgenic lines (T1 exhibited higher chlorophyll, relative water, proline, total sugar, reducing sugar, free amino acids, polyphenol contents, osmotic potential, membrane stability and lower electrolyte leakage and lipid peroxidation (malondialdehyde content under stress treatments than control (WT and VC plants. Lower accumulation of H2O2 and O2- radicals was also detected in transgenic lines compared to control plants under stress conditions. Present study confers that overexpression of the SbUSP gene enhances plant growth, alleviates ROS buildup, maintains ion homeostasis and improves the physiological status of the plant under salt and osmotic stresses. Principal component analysis (PCA exhibited a statistical distinction of plant response to salinity stress, and a significant response was observed for transgenic lines under stress, which provides stress endurance to the plant. A possible signaling role is proposed that some downstream genes may get activated by abiotic stress responsive cytosolic SbUSP, which leads to the protection of cell from oxidative damages. The study unveils that ectopic expression of the gene mitigates salt or osmotic stress by scavenging ROS and modulating the physiological process of the plant.

  14. Biological stress response terminology: Integrating the concepts of adaptive response and preconditioning stress within a hormetic dose-response framework

    Many biological subdisciplines that regularly assess dose-response relationships have identified an evolutionarily conserved process in which a low dose of a stressful stimulus activates an adaptive response that increases the resistance of the cell or organism to a moderate to severe level of stress. Due to a lack of frequent interaction among scientists in these many areas, there has emerged a broad range of terms that describe such dose-response relationships. This situation has become problematic because the different terms describe a family of similar biological responses (e.g., adaptive response, preconditioning, hormesis), adversely affecting interdisciplinary communication, and possibly even obscuring generalizable features and central biological concepts. With support from scientists in a broad range of disciplines, this article offers a set of recommendations we believe can achieve greater conceptual harmony in dose-response terminology, as well as better understanding and communication across the broad spectrum of biological disciplines

  15. The cytochrome c oxidase biogenesis factor AtCOX17 modulates stress responses in Arabidopsis.

    Garcia, Lucila; Welchen, Elina; Gey, Uta; Arce, Agustín L; Steinebrunner, Iris; Gonzalez, Daniel H

    2016-03-01

    COX17 is a soluble protein from the mitochondrial intermembrane space that participates in the transfer of copper for cytochrome c oxidase (COX) assembly in eukaryotic organisms. In this work, we studied the function of both Arabidopsis thaliana AtCOX17 genes using plants with altered expression levels of these genes. Silencing of AtCOX17-1 in a cox17-2 knockout background generates plants with smaller rosettes and decreased expression of genes involved in the response of plants to different stress conditions, including several genes that are induced by mitochondrial dysfunctions. Silencing of either of the AtCOX17 genes does not affect plant development or COX activity but causes a decrease in the response of genes to salt stress. In addition, these plants contain higher reactive oxygen and lipid peroxidation levels after irrigation with high NaCl concentrations and are less sensitive to abscisic acid. In agreement with a role of AtCOX17 in stress and abscisic acid responses, both AtCOX17 genes are induced by several stress conditions, abscisic acid and mutation of the transcription factor ABI4. The results indicate that AtCOX17 is required for optimal expression of a group of stress-responsive genes, probably as a component of signalling pathways that link stress conditions to gene expression responses. PMID:26436309

  16. Regulation of oxidative stress response by CosR, an essential response regulator in Campylobacter jejuni.

    Sunyoung Hwang

    Full Text Available CosR (Campylobacter oxidative stress regulator; Cj0355c is an OmpR-type response regulator essential for the viability of Campylobacter jejuni, a leading foodborne pathogen causing human gastroenteritis worldwide. Despite importance, the function of CosR remains completely unknown mainly because of cell death caused by its knockout mutation. To overcome this technical limitation, in this study, antisense technology was used to investigate the regulatory function of CosR by modulating the level of CosR expression. Two-dimensional gel electrophoresis (2DGE was performed to identify the CosR regulon either by suppressing CosR expression with antisense peptide nucleic acid (PNA or by overexpressing CosR in C. jejuni. According to the results of 2DGE, CosR regulated 32 proteins involved in various cellular processes. Notably, CosR negatively regulated a few key proteins of the oxidative stress response of C. jejuni, such as SodB, Dps, Rrc and LuxS, whereas CosR positively controlled AhpC. Electrophoretic mobility shift assay showed that CosR directly bound to the promoter region of the oxidative stress genes. DNase I footprinting assays identified 21-bp CosR binding sequences in the sodB and ahpC promoters, suggesting CosR specifically recognizes and binds to the regulated genes. Interestingly, the level of CosR protein was significantly reduced by paraquat (a superoxide generator but not by hydrogen peroxide. Consistent with the overall negative regulation of oxidative stress defense proteins by CosR, the CosR knockdown by antisense rendered C. jejuni more resistant to oxidative stress compared to the wild type. Overall, this study reveals the important role played by the essential response regulator CosR in the oxidative stress defense of C. jejuni.

  17. Neurovascular responses to mental stress in prehypertensive humans

    Schwartz, Christopher E.; Durocher, John J.; Carter, Jason R.

    2010-01-01

    Neurovascular responses to mental stress have been linked to several cardiovascular diseases, including hypertension. Mean arterial pressure (MAP), muscle sympathetic nerve activity (MSNA), and forearm vascular responses to mental stress are well documented in normotensive (NT) subjects, but responses in prehypertensive (PHT) subjects remain unclear. We tested the hypothesis that PHT would elicit a more dramatic increase of MAP during mental stress via augmented MSNA and blunted forearm vascu...

  18. Plasma transcortin influences endocrine and behavioral stress responses in mice

    Richard, Elodie M.; Helbling, Jean-Christophe; Tridon, Claudine; Desmedt, Aline; Minni, Amandine; Cador, Martine; Pourtau, Line; Konsman, Jan Peter; Mormède, Pierre; Moisan, Marie-Pierre

    2010-01-01

    Glucocorticoids are released after hypothalamus-pituitary-adrenal axis stimulation by stress and act both in the periphery and in the brain to bring about adaptive responses that are essential for life. Dysregulation of the stress response can precipitate psychiatric diseases, in particular depression. Recent genetic studies have suggested that the glucocorticoid carrier transcortin, also called corticosteroid-binding globulin (CBG), may have an important role in stress response. We have inve...

  19. A central role of abscisic acid in stress-regulated carbohydrate metabolism.

    Stefan Kempa

    Full Text Available BACKGROUND: Abiotic stresses adversely affect plant growth and development. The hormone abscisic acid (ABA plays a central role in the response and adaptation to environmental constraints. However, apart from the well established role of ABA in regulating gene expression programmes, little is known about its function in plant stress metabolism. PRINCIPAL FINDINGS: Using an integrative multiparallel approach of metabolome and transcriptome analyses, we studied the dynamic response of the model glyophyte Arabidopsis thaliana to ABA and high salt conditions. Our work shows that salt stress induces complex re-adjustment of carbohydrate metabolism and that ABA triggers the initial steps of carbon mobilisation. SIGNIFICANCE: These findings open new perspectives on how high salinity and ABA impact on central carbohydrate metabolism and highlight the power of iterative combinatorial approaches of non-targeted and hypothesis-driven experiments in stress biology.

  20. Molecular and physiological responses of sunflower (helianthus annuus l.) to pgpr and sa under salt stress

    This paper presents the efficacy of PGPR (Azospirillum and Pseudomonas) and its modulation by salicylic acid. Two hybrids of sunflower (Hysun and Parsun) were inoculated with Azospirillum spp. and Pseudomonas spp. prior to sowing. Salt stress (20 dSm-1) was applied 28 d after sowing followed by foliar spray of salicylic acid (100 micro M) after 4 h of salt treatment. Azospirillum and Pseudomonas inoculation alone and in combination with salicylic acid alleviated the effects of salt stress on both the sunflower hybrids. The salt tolerance in these treatments was mediated by an increase in relative water content, carotenoids, proline, ABA, induction of new polypeptide bands and yield of sunflower hybrids. In response to salt stress four new polypeptide bands were synthesized in both Hysun, whereas, a group of six polypeptide bands were observed in Parsun. Application of salicylic acid alone and in combination with Azospirillum found to induce four new polypeptide bands in Hysun and Parsun. It is inferred that synthesis of new proteins in response to the combined application of salicylic acid and Azospirillum under salt stress, may play an important role as stress proteins in tolerance of sunflower hybrids to salt stress. (author)

  1. Decrypting the H-NS-dependent regulatory cascade of acid stress resistance in Escherichia coli

    Soutourina Olga

    2010-10-01

    Full Text Available Abstract Background H-NS regulates the acid stress resistance. The present study aimed to characterize the H-NS-dependent cascade governing the acid stress resistance pathways and to define the interplay between the different regulators. Results We combined mutational, phenotypic and gene expression analyses, to unravel the regulatory hierarchy in acid resistance involving H-NS, RcsB-P/GadE complex, HdfR, CadC, AdiY regulators, and DNA-binding assays to separate direct effects from indirect ones. RcsB-P/GadE regulatory complex, the general direct regulator of glutamate-, arginine- and lysine-dependent acid resistance pathways plays a central role in the regulatory cascade. However, H-NS also directly controls specific regulators of these pathways (e.g. cadC and genes involved in general stress resistance (hdeAB, hdeD, dps, adiY. Finally, we found that in addition to H-NS and RcsB, a third regulator, HdfR, inversely controls glutamate-dependent acid resistance pathway and motility. Conclusions H-NS lies near the top of the hierarchy orchestrating acid response centred on RcsB-P/GadE regulatory complex, the general direct regulator of glutamate-, arginine- and lysine-dependent acid resistance pathways.

  2. Detection of Acid Rain Stress Effect on Plant Using Hyperspectral Data in Three Gorges Region,China

    SONG Xiaodong; JIANG Hong; YU Shuquan; ZHOU Guomo

    2008-01-01

    This paper aims to use hyperspectral data to detect the spectral change caused by acid stress to a native forest type in the Three Gorges region of China.For this purpose,a ground-based hyperspectral experiment was conducted at the Three Gorges region to detect acid deposition that caused Masson pine (Pinus massoniana) forest degradation.Continuum removal method was used to isolate wavebands more responsive to stress in wavelengths 450-750nm.The differences in chlorophyll concentrations and needle thickness caused by acidic stress are found to be explicable to the different spectral reflectance patterns in the visible and near-infrared wavelengths.Two new chlorotic indices were utilized to explain the stress-caused leaf chiorosis.The comparison of simulated vegetation indices and principal component analysis (PCA) results suggests that it would be possible to monitor acid rain stress effect on forest ecosystem from some wider spectral regions.

  3. Response of plants to water stress

    Osakabe, Yuriko; Osakabe, Keishi; Shinozaki, Kazuo; Tran, Lam-Son P.

    2014-01-01

    Water stress adversely impacts many aspects of the physiology of plants, especially photosynthetic capacity. If the stress is prolonged, plant growth, and productivity are severely diminished. Plants have evolved complex physiological and biochemical adaptations to adjust and adapt to a variety of environmental stresses. The molecular and physiological mechanisms associated with water-stress tolerance and water-use efficiency have been extensively studied. The systems that regulate plant adap...

  4. Overexpression of a Cytosolic Abiotic Stress Responsive Universal Stress Protein (SbUSP) Mitigates Salt and Osmotic Stress in Transgenic Tobacco Plants.

    Udawat, Pushpika; Jha, Rajesh K; Sinha, Dinkar; Mishra, Avinash; Jha, Bhavanath

    2016-01-01

    The universal stress protein (USP) is a ubiquitous protein and plays an indispensable role in plant abiotic stress tolerance. The genome of Salicornia brachiata contains two homologs of intron less SbUSP gene which encodes for salt and osmotic responsive USP. In vivo localization reveals that SbUSP is a membrane bound cytosolic protein. The role of the gene was functionally validated by developing transgenic tobacco and compared with control [wild-type (WT) and vector control (VC)] plants under different abiotic stress condition. Transgenic lines (T1) exhibited higher chlorophyll, relative water, proline, total sugar, reducing sugar, free amino acids, polyphenol contents, osmotic potential, membrane stability, and lower electrolyte leakage and lipid peroxidation (malondialdehyde content) under stress treatments than control (WT and VC) plants. Lower accumulation of H2O2 and [Formula: see text] radicals was also detected in transgenic lines compared to control plants under stress conditions. Present study confers that overexpression of the SbUSP gene enhances plant growth, alleviates ROS buildup, maintains ion homeostasis and improves the physiological status of the plant under salt and osmotic stresses. Principal component analysis exhibited a statistical distinction of plant response to salinity stress, and a significant response was observed for transgenic lines under stress, which provides stress endurance to the plant. A possible signaling role is proposed that some downstream genes may get activated by abiotic stress responsive cytosolic SbUSP, which leads to the protection of cell from oxidative damages. The study unveils that ectopic expression of the gene mitigates salt or osmotic stress by scavenging ROS and modulating the physiological process of the plant. PMID:27148338

  5. Origins of asymmetric stress-strain response in phase transformations

    Sehitoglu, H.; Gall, K. [Univ. of Illinois, Urbana, IL (United States)

    1997-12-31

    It has been determined that the transformation stress-strain behavior of CuZnAl and NiTi shape memory alloys is dependent on the applied stress state. The uniaxial compressive stress necessary to macroscopically trigger the transformation is approximately 34% (CuZnAl) and 26% (NiTi) larger than the required uniaxial tensile stress. For three dimensional stress states, the response of either alloy system is dependent on the directions of the dominant principal stresses along with the hydrostatic stress component of the stress state. The stress state effects are dominated by the favored growth and nucleation of more martensite plates in tension versus compression. The effect of different hydrostatic pressure levels between stress states on martensite plates volume change is considered small.

  6. Maternal Influences on Youth Responses to Peer Stress

    Abaied, Jamie L.; Rudolph, Karen D.

    2011-01-01

    Understanding how youths develop particular styles of responding to stress is critical for promoting effective coping. This research examined the prospective, interactive contribution of maternal socialization of coping and peer stress to youth responses to peer stress. A sample of 144 early adolescents (mean age = 12.44 years, SD = 1.22) and…

  7. The Stress Response Regulator AflSkn7 Influences Morphological Development, Stress Response, and Pathogenicity in the Fungus Aspergillus flavus

    Zhang, Feng; Xu, Gaopo; Geng, Longpo; Lu, Xiaoyan; Yang, Kunlong; Yuan, Jun; Nie, Xinyi; Zhuang, Zhenhong; Wang, Shihua

    2016-01-01

    This study focused on AflSkn7, which is a stress response regulator in the aflatoxin-producing Aspergillus flavus. The ΔAflSkn7 mutants exhibited partially defective conidial formation and a complete inability to generate sclerotia, indicating AflSkn7 affects A. flavus asexual and sexual development. The mutants tolerated osmotic stress but were partially susceptible to the effects of cell wall stress. Additionally, the ΔAflSkn7 mutants were especially sensitive to oxidative stress. These observations confirmed that AflSkn7 influences oxidative stress responses rather than osmotic stress responses. Additionally, AflSkn7 was observed to increase aflatoxin biosynthesis and seed infection rates. These results indicate AflSkn7 affects A. flavus morphological development, stress response, aflatoxin production, and pathogenicity. The results of this study may facilitate the development of new methods to manage A. flavus infections. PMID:27399770

  8. Computations of uncertainty mediate acute stress responses in humans.

    de Berker, Archy O; Rutledge, Robb B; Mathys, Christoph; Marshall, Louise; Cross, Gemma F; Dolan, Raymond J; Bestmann, Sven

    2016-01-01

    The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function. PMID:27020312

  9. Relation between stress-precipitated seizures and the stress response in childhood epilepsy.

    van Campen, Jolien S; Jansen, Floor E; Pet, Milou A; Otte, Willem M; Hillegers, Manon H J; Joels, Marian; Braun, Kees P J

    2015-08-01

    The majority of patients with epilepsy report that seizures are sometimes triggered or provoked. Stress is the most frequently self-reported seizure-precipitant. The mechanisms underlying stress-sensitivity of seizures are currently unresolved. We hypothesized that stress-sensitivity of seizures relates to alteration of the stress response, which could affect neuronal excitability and hence trigger seizures. To study this, children with epilepsy between 6 and 17 years of age and healthy controls, with similar age, sex and intelligence, were exposed to a standardized acute psychosocial stressor (the Trier Social Stress Test for Children), during which salivary cortisol and sympathetic parameters were measured. Beforehand, the relation between stress and seizures in children with epilepsy was assessed by (i) a retrospective questionnaire; and (ii) a prospective 6-week diary on stress and seizure occurrence. Sixty-four children with epilepsy and 40 control subjects were included in the study. Of all children with epilepsy, 49% reported that seizures were precipitated by acute stress. Diary analysis showed a positive association between acute stress and seizures in 62% of children who experienced at least one seizure during the diary period. The acute social stress test was completed by 56 children with epilepsy and 37 control subjects. Children with sensitivity of seizures for acute stress, either determined by the questionnaire or by the prospective diary, showed a blunted cortisol response to stress compared with patients without acute stress-precipitated seizures and healthy controls (questionnaire-based F = 2.74, P = 0.018; diary-based F = 4.40, P = 0.007). No baseline differences in cortisol were observed, nor differences in sympathetic stress response. The relation between acute stress-sensitivity of seizures and the cortisol response to stress remained significant in multivariable analysis (β = -0.30, P = 0.03). Other variables associated with the acute stress

  10. Psychophysiological responses to stress after stress management training in patients with rheumatoid arthritis.

    Sabine J M de Brouwer

    Full Text Available BACKGROUND: Stress management interventions may prove useful in preventing the detrimental effects of stress on health. This study assessed the effects of a stress management intervention on the psychophysiological response to stress in patients with rheumatoid arthritis (RA. METHODS: Seventy-four patients with RA, who were randomly assigned to either a control group or a group that received short-term stress management training, performed a standardized psychosocial stress task (Trier Social Stress Test; TSST 1 week after the stress management training and at a 9-week follow-up. Psychological and physical functioning, and the acute psychophysiological response to the stress test were assessed. RESULTS: Patients in the intervention group showed significantly lower psychological distress levels of anxiety after the training than did the controls. While there were no between-group differences in stress-induced tension levels, and autonomic (α-amylase or endocrine (cortisol responses to the stress test 1 week after the intervention, levels of stress-induced tension and cortisol were significantly lower in the intervention group at the 9-week follow-up. Overall, the response to the intervention was particularly evident in a subgroup of patients with a psychological risk profile. CONCLUSION: A relatively short stress management intervention can improve psychological functioning and influences the psychophysiological response to stress in patients with RA, particularly those psychologically at risk. These findings might help understand how stress can affect health and the role of individual differences in stress responsiveness. TRIAL REGISTRATION: TrialRegister.nl NTR1193.

  11. Proteomic studies of drought stress response in Fabaceae

    Tanja ZADRAŽNIK

    2015-11-01

    Full Text Available Drought stress is a serious threat to crop production that influences plant growth and development and subsequently causes reduced quantity and quality of the yield. Plant stress induces changes in cell metabolism, which includes differential expression of proteins. Proteomics offer a powerful approach to analyse proteins involved in drought stress response of plants. Analyses of changes in protein abundance of legumes under drought stress are very important, as legumes play an important role in human and animal diet and are often exposed to drought. The presented results of proteomic studies of selected legumes enable better understanding of molecular mechanisms of drought stress response. The study of drought stress response of plants with proteomic approach may contribute to the development of potential drought-response markers and to the development of drought-tolerant cultivars of different legume crop species.

  12. Proteomic studies of drought stress response in Fabaceae

    Zadražnik, Tanja; Jelka ŠUŠTAR-VOZLIČ

    2015-01-01

    Drought stress is a serious threat to crop production that influences plant growth and development and subsequently causes reduced quantity and quality of the yield. Plant stress induces changes in cell metabolism, which includes differential expression of proteins. Proteomics offer a powerful approach to analyse proteins involved in drought stress response of plants. Analyses of changes in protein abundance of legumes under drought stress are very important, as legumes play an important role...

  13. Stress in university students and cardiovascular response to academic stressors

    Guimarães, Teresa; Silva, Ana Patrícia; Monteiro, Iolanda; Gomes, Rui

    2014-01-01

    Introduction: University students are frequently exposed to events that can cause stress and anxiety, producing elevated cardiovascular responses. Repeated exposure to academic stress has implications to students’ success and well-being and may contribute to the development of long-term health problems. Objective: To identify stress levels and coping strategies in university students and assess the impact of stress experience in heart rate variability (HRV). Methods: 17 university students, 1...

  14. Plant hormone-mediated regulation of stress responses

    Verma, Vivek; Ravindran, Pratibha; Kumar, Prakash P.

    2016-01-01

    Background Being sessile organisms, plants are often exposed to a wide array of abiotic and biotic stresses. Abiotic stress conditions include drought, heat, cold and salinity, whereas biotic stress arises mainly from bacteria, fungi, viruses, nematodes and insects. To adapt to such adverse situations, plants have evolved well-developed mechanisms that help to perceive the stress signal and enable optimal growth response. Phytohormones play critical roles in helping the plants to adapt to adv...

  15. Hormonal modulation of the heat shock response: insights from fish with divergent cortisol stress responses

    LeBlanc, Sacha; Höglund, Erik; Gilmour, Kathleen M.;

    2012-01-01

    Acute temperature stress in animals results in increases in heat shock proteins (HSPs) and stress hormones. There is evidence that stress hormones influence the magnitude of the heat shock response; however, their role is equivocal. To determine whether and how stress hormones may affect the heat...... shock response, we capitalized on two lines of rainbow trout specifically bred for their high (HR) and low (LR) cortisol response to stress. We predicted that LR fish, with a low cortisol but high catecholamine response to stress, would induce higher levels of HSPs after acute heat stress than HR trout....... We found that HR fish have significantly higher increases in both catecholamines and cortisol compared with LR fish, and LR fish had no appreciable stress hormone response to heat shock. This unexpected finding prevented further interpretation of the hormonal modulation of the heat shock response but...

  16. Context and strain-dependent behavioral response to stress

    Baum Amber E; Ahmadiyeh Nasim; Andrus Brian M; Dennis Kristen; Nosek Katarzyna; Woods Leah; Redei Eva E

    2008-01-01

    Abstract Background This study posed the question whether strain differences in stress-reactivity lead to differential behavioral responses in two different tests of anxiety. Strain differences in anxiety-measures are known, but strain differences in the behavioral responses to acute prior stress are not well characterized. Methods We studied male Fisher 344 (F344) and Wistar Kyoto (WKY) rats basally and immediately after one hour restraint stress. To distinguish between the effects of novelt...

  17. Oxidative stress response in Lactobacillus plantarum WCFS1: a functional genomics approach

    Serrano, L. M.

    2008-01-01

    Control of activity and functionality of microbial starter and probiotic cultures under industrial fermentation conditions is essential in order to provide a tasty, appealing, healthy, and safe product. Oxidative stress is one of the harsh conditions that fermentative microbes have managed to endure during their use in industrial fermentation processes. A widely-used lactic acid bacterium in food fermentations is Lactobacillus plantarum. Hence, understanding oxidative stress response in this ...

  18. Lignification response for rolled leaves of Ctenanthe setosa under long-term drought stress

    TERZİ, Rabiye; GÜLER, Neslihan SARUHAN; ÇALIŞKAN, Nihal KUTLU; KADIOĞLU, Asım

    2013-01-01

    Leaf rolling is a dehydration avoidance mechanism for plants under drought stress. To understand how it affects the lignification process in response to long-term drought stress in Ctenanthe setosa plants that have the leaf-rolling mechanism, the enzymes in lignification were studied in unrolled leaves as a control and at 2 different leaf rolling indices at days 35 and 47 of the drought period. The results indicated that the activities of phenylalanine ammonia lyase, indole-3-acetic acid oxid...

  19. Brain Endoplasmic Reticulum Stress Mechanistically Distinguishes the Saline-Intake and Hypertensive Response to DOCA-Salt

    Jo, Fusakazu; Jo, Hiromi; Hilzendeger, Aline M.; Thompson, Anthony P.; Cassell, Martin D.; Rutkowski, D. Thomas; Davisson, Robin L.; Grobe, Justin L.; Sigmund, Curt D.

    2015-01-01

    Endoplasmic reticulum stress has become an important mechanism in hypertension. We examined the role of endoplasmic reticulum stress in mediating the increased saline intake and hypertensive effects in response to DOCA-salt. Intracerebroventricular delivery of the endoplasmic reticulum stress-reducing chemical chaperone Tauroursodeoxycholic acid did not affect the magnitude of hypertension, but markedly decreased saline intake in response to DOCA-salt. Increased saline intake returned after T...

  20. Stress corrosion cracking of zirconium in nitric acid

    The susceptibility of zirconium and its common alloys to stress corrosion cracking (SCC) in nitric acid was investigated by slow strain-rate and constant deflection techniques. Cracking occurred at 250C over a wide range of acid concentrations and electrochemical potentials. The crack velocity increased slightly with increasing temperature. The failure mode was transgranular and the morphology was similar to SCC failures of zirconium alloys in other environments. The fracture was very orientation-dependent suggesting that it occurs on a single crystallographic plane in the material. The results of the study are not consistent with a hydrogen mechanism for cracking

  1. Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions

    The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 μM uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 μM uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress. - Highlights

  2. Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions

    Vanhoudt, Nathalie, E-mail: nvanhoud@sckcen.be [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Cuypers, Ann [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Horemans, Nele [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Remans, Tony; Opdenakker, Kelly; Smeets, Karen [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Bello, Daniel Martinez [Hasselt University, Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Agoralaan Building D, 3590 Diepenbeek (Belgium); Havaux, Michel [Commissariat a l' Energie Atomique (CEA)/Cadarache, Direction des Sciences du Vivant, Departement d' Ecophysiologie Vegetale et de Microbiologie, Laboratoire d' Ecophysiologie de la Photosynthese, 13108 Saint-Paul-lez-Durance (France); Wannijn, Jean; Van Hees, May [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Vangronsveld, Jaco [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Vandenhove, Hildegarde [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

    2011-06-15

    The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 {mu}M uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 {mu}M uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress

  3. [Cardioprotective properties of new glutamic acid derivative under stress conditions].

    Perfilova, V N; Sadikova, N V; Berestovitskaia, V M; Vasil'eva, O S

    2014-01-01

    The effect of new glutamic acid derivative on the cardiac ino- and chronotropic functions has been studied in experiments on rats exposed to 24-hour immobilization-and-pain stress. It is established that glutamic acid derivative RGPU-238 (glufimet) at a dose of 28.7 mg/kg increases the increment of myocardial contractility and relaxation rates and left ventricular pressure in stress-tested animals by 13 1,1, 72.4, and 118.6%, respectively, as compared to the control group during the test for adrenoreactivity. Compound RGPU-238 increases the increment of the maximum intensity of myocardium functioning by 196.5 % at 30 sec of isometric workload as compared to the control group. The cardioprotective effect of compound RGPU-238 is 1.5 - 2 times higher than that of the reference drug phenibut. PMID:25365864

  4. Stearic acid protects primary cultured cortical neurons against oxidative stress

    Ze-jian WANG; Cui-ling LIANG; Guang-mei LI; Cai-yi YU; Ming YIN

    2007-01-01

    Aim: To observe the effects of stearic acid against oxidative stress in primary cultured cortical neurons. Methods: Cortical neurons were exposed to glutamate,hydrogen peroxide (H202), or NaN3 insult in the presence or absence of stearic acid. Cell viability of cortical neurons was determined by MTT assay and LDH release. Endogenous antioxidant enzymes activity[superoxide dismutases (SOD),glutathione peroxidase (GSH-Px), and catalase (CAT)] and lipid peroxidation in cultured cortical neurons were evaluated using commercial kits. {3-[1(p-chloro-benzyl)-5-(isopropyl)-3-t-butylthiondol-2-yl]-2,2-dimethylpropanoic acid, Na}[MK886; 5 pmol/L; a noncompetitive inhibitor of proliferator-activated receptor(PPAR)α], bisphenol A diglycidyl ether (BADGE; 100 μmol/L; an antagonist of PPARγ), and cycloheximide (CHX; 30 μmol/L, an inhibitor of protein synthesis)were tested for their effects on the neuroprotection afforded by stearic acid.Western blotting was used to determine the PPARγ protein level in cortical neurons.Results: Stearic acid dose-dependently protected cortical neurons against glutamate or H202 injury and increased glutamate uptake in cultured neurons.This protection was concomitant to the inhibition of lipid peroxidation and to the promotion activity of Cu/Zn SOD and CAT in cultured cortical neurons. Its neuroprotective effects were completely blocked by BADGE and CHX. After incubation with H2O2 for 24 h, the expression of the PPARγ protein decreased significantly (P<0.05), and the inhibitory effect of H2O2 on the expression of PPARγ can be attenuated by stearic acid. Conclusion: Stearic acid can protect cortical neurons against oxidative stress by boosting the internal antioxidant enzymes.Its neuroprotective effect may be mainly mediated by the activation of PPARγ and new protein synthesis in cortical neurons.

  5. Stress Response and Perinatal Reprogramming: Unraveling (Mal)adaptive Strategies.

    Musazzi, Laura; Marrocco, Jordan

    2016-01-01

    Environmental stressors induce coping strategies in the majority of individuals. The stress response, involving the activation of the hypothalamic-pituitary-adrenocortical axis and the consequent release of corticosteroid hormones, is indeed aimed at promoting metabolic, functional, and behavioral adaptations. However, behavioral stress is also associated with fast and long-lasting neurochemical, structural, and behavioral changes, leading to long-term remodeling of glutamate transmission, and increased susceptibility to neuropsychiatric disorders. Of note, early-life events, both in utero and during the early postnatal life, trigger reprogramming of the stress response, which is often associated with loss of stress resilience and ensuing neurobehavioral (mal)adaptations. Indeed, adverse experiences in early life are known to induce long-term stress-related neuropsychiatric disorders in vulnerable individuals. Here, we discuss recent findings about stress remodeling of excitatory neurotransmission and brain morphology in animal models of behavioral stress. These changes are likely driven by epigenetic factors that lie at the core of the stress-response reprogramming in individuals with a history of perinatal stress. We propose that reprogramming mechanisms may underlie the reorganization of excitatory neurotransmission in the short- and long-term response to stressful stimuli. PMID:27057367

  6. Molecular Mechanism of Rice in Response to Salt Stress

    E Zhi-guo; ZHANG Li-jing; WANG Lei

    2011-01-01

    Rice is moderately sensitive to salinity,and the response to salt stress is a complex process,including the perception and transduction of salt stress signal,the activation of specific transcriptional factors and the expression of downstream stress-responsive genes.The functions of Na+ transporters which are involved in the maintenance and reconstruction of the ion homeostasis,transcriptional regulators and osmotic regulation genes were reviewed.Salt tolerance of plants are enhanced by Na+ vacuolar compartmentation or efflux or high levels of osmoprotectants accumulation in cytoplasm.%Rice is moderately sensitive to salinity,and the response to salt stress is a complex process,including the perception and transduction of salt stress signal,the activation of specific transcriptional factors and the expression of downstream stress-respon

  7. Sex differences in synaptic plasticity in stress-responsive brain regions following chronic variable stress

    Carvalho-Netto, Eduardo F.; Myers, Brent; Jones, Kenneth; Solomon, Matia B.; Herman, James P.

    2011-01-01

    Increased stress responsiveness is implicated in the etiology of mood and anxiety disorders, including depression and post-traumatic stress disorder. Additionally, stress-related affective disorders have a higher incidence in women than men. Chronic stress in rodents produces numerous neuromorphological changes in a variety of limbic brain regions. Here, we examined the sex-dependent differences in presynaptic innervation of the paraventricular nucleus of the hypothalamus (PVN), prefrontal co...

  8. Oxidative Stress in Dog with Heart Failure: The Role of Dietary Fatty Acids and Antioxidants

    Emmanuelle Sagols

    2011-01-01

    Full Text Available In dogs with heart failure, cell oxygenation and cellular metabolism do not work properly, leading to the production of a large amount of free radicals. In the organism, these free radicals are responsible of major cellular damages: this is oxidative stress. However, a suitable food intake plays an important role in limiting this phenomenon: on the one hand, the presence of essential fatty acids in the composition of membranes decreases sensitivity of cells to free radicals and constitutes a first protection against the oxidative stress; on the other hand, coenzyme Q10, vitamin E, and polyphenols are antioxidant molecules which can help cells to neutralize these free radicals.

  9. Oxidative Stress in Dog with Heart Failure: The Role of Dietary Fatty Acids and Antioxidants

    Emmanuelle Sagols; Nathalie Priymenko

    2011-01-01

    In dogs with heart failure, cell oxygenation and cellular metabolism do not work properly, leading to the production of a large amount of free radicals. In the organism, these free radicals are responsible of major cellular damages: this is oxidative stress. However, a suitable food intake plays an important role in limiting this phenomenon: on the one hand, the presence of essential fatty acids in the composition of membranes decreases sensitivity of cells to free radicals and constitutes a ...

  10. Molecular mechanisms of the plant heat stress response

    Qu, Ai-Li; Ding, Yan-Fei; Jiang, Qiong [China Jiliang University, Xueyuan Road 258, Hangzhou 310018 (China); Zhu, Cheng, E-mail: pzhch@cjlu.edu.cn [China Jiliang University, Xueyuan Road 258, Hangzhou 310018 (China)

    2013-03-08

    Highlights: ► This review elaborates the response networks of heat stress in plants. ► It elaborates proteins responding to heat stress in special physiological period. ► The proteins and pathways have formed a basic network of the heat stress response. ► Achievements of the various technologies are also combined. -- Abstract: High temperature has become a global concern, which seriously affects the growth and production of plants, particularly crops. Thus, the molecular mechanism of the heat stress response and breeding of heat-tolerant plants is necessary to protect food production and ensure crop safety. This review elaborates on the response networks of heat stress in plants, including the Hsf and Hsp response pathways, the response of ROS and the network of the hormones. In addition, the production of heat stress response elements during particular physiological periods of the plant is described. We also discuss the existing problems and future prospects concerning the molecular mechanisms of the heat stress response in plants.

  11. Accumulation of Flavonols over Hydroxycinnamic Acids Favors Oxidative Damage Protection under Abiotic Stress

    Martinez, Vicente; Mestre, Teresa C.; Rubio, Francisco; Girones-Vilaplana, Amadeo; Moreno, Diego A.; Mittler, Ron; Rivero, Rosa M.

    2016-01-01

    Efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Although multiple pathways, enzymes, and antioxidants are present in plants, their exact roles during different stress responses remain unclear. Here, we report on the characterization of the different antioxidant mechanisms of tomato plants subjected to heat stress, salinity stress, or a combination of both stresses. All the treatments applied induced an increase of oxidative stress, with the salinity treatment being the most aggressive, resulting in plants with the lowest biomass, and the highest levels of H2O2 accumulation, lipid peroxidation, and protein oxidation. However, the results obtained from the transcript expression study and enzymatic activities related to the ascorbate-glutathione pathway did not fully explain the differences in the oxidative damage observed between salinity and the combination of salinity and heat. An exhaustive metabolomics study revealed the differential accumulation of phenolic compounds depending on the type of abiotic stress applied. An analysis at gene and enzyme levels of the phenylpropanoid metabolism concluded that under conditions where flavonols accumulated to a greater degree as compared to hydroxycinnamic acids, the oxidative damage was lower, highlighting the importance of flavonols as powerful antioxidants, and their role in abiotic stress tolerance. PMID:27379130

  12. Role of shame and body esteem in cortisol stress responses.

    Lupis, Sarah B; Sabik, Natalie J; Wolf, Jutta M

    2016-04-01

    Studies assessing the role of shame in HPA axis reactivity report mixed findings. Discrepancies may be due to methodological difficulties and inter-individual differences in the propensity to experience shame in a stressful situation. Hence, the current study combined self-report of shame and facial coding of shame expressions and assessed the role of body esteem as a moderator of the shame-stress link. For this, 44 healthy students (24F, age 20.5 ± 2.1 years) were exposed to an acute psychosocial stress paradigm (Trier Social Stress Test: TSST). Salivary cortisol levels were measured throughout the protocol. Trait shame was measured before the stress test, and state shame immediately afterwards. Video recordings of the TSST were coded to determine emotion expressions. State shame was neither associated with cortisol stress responses nor with body esteem (self-report: all ps ≥ .24; expression: all ps ≥ .31). In contrast, higher trait shame was associated with both negative body esteem (p = .049) and stronger cortisol stress responses (p = .013). Lastly, having lower body esteem predicted stronger cortisol stress responses (p = .022); however, it did not significantly moderate the association between shame indices and cortisol stress responses (all ps ≥ .94). These findings suggest that body esteem and trait shame independently contribute to strength of cortisol stress responses. Thus, in addition to trait shame, body esteem emerged as an important predictor of cortisol stress responses and as such, a potential contributor to stress-related negative health outcomes. PMID:26577952

  13. Involvement of Histone Modifications in Plant Abiotic Stress Responses

    Lianyu Yuan; Xuncheng Liu; Ming Luo; Songguang Yang; Keqiang Wu

    2013-01-01

    As sessile organisms, plants encounter various environmental stimuli including abiotic stresses during their lifecycle. To survive under adverse conditions, plants have evolved intricate mechanisms to perceive external signals and respond accordingly. Responses to various stresses largely depend on the plant capacity to modulate the transcriptome rapidly and specifically. A number of studies have shown that the molecular mechanisms driving the responses of plants to environmental stresses often depend on nucleosome histone post-translational modifications including histone acetylation, methylation, ubiquitination, and phosphorylation. The combined effects of these modifications play an essential role in the regulation of stress responsive gene expression. In this review, we highlight our current understanding of the epigenetic mechanisms of histone modifications and their roles in plant abiotic stress response.

  14. Nitric Oxide Signaling in Plant Responses to Abiotic Stresses

    Weihua Qiao; LiuMin Fan

    2008-01-01

    Nitric oxide (NO) plays important roles in diverse physiological processes In plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.

  15. Spatial characterization of acid rain stress in Canadian Shield Lakes

    Tanis, F. J.; Marshall, E. M.

    1989-01-01

    The lake acidification in Northern Ontario was investigated using LANDSAT TM to sense lake volume reflectance and also to provide important vegetation and terrain characteristics. The purpose of this project was to determine the ability of LANDSAT to assess water quality characteristics associated with lake acidification. Results demonstrate that a remote sensor can discriminate lake clarity based upon reflection. The basic hypothesis is that seasonal and multi-year changes in lake optical transparency are indicative of sensitivity to acidic deposition. In many acid-sensitive lakes optical transparency is controlled by the amount of dissolved organic carbon present. Seasonal changes in the optical transparency of lakes can potentially provide an indication of the stress due to acid deposition and loading.

  16. AMPK-independent inhibition of human macrophage ER stress response by AICAR.

    Boß, Marcel; Newbatt, Yvette; Gupta, Sahil; Collins, Ian; Brüne, Bernhard; Namgaladze, Dmitry

    2016-01-01

    Obesity-associated insulin resistance is driven by inflammatory processes in response to metabolic overload. Obesity-associated inflammation can be recapitulated in cell culture by exposing macrophages to saturated fatty acids (SFA), and endoplasmic reticulum (ER) stress responses essentially contribute to pro-inflammatory signalling. AMP-activated protein kinase (AMPK) is a central metabolic regulator with established anti-inflammatory actions. Whether pharmacological AMPK activation suppresses SFA-induced inflammation in a human system is unclear. In a setting of hypoxia-potentiated inflammation induced by SFA palmitate, we found that the AMP-mimetic AMPK activator 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) potently suppressed upregulation of ER stress marker mRNAs and pro-inflammatory cytokines. Furthermore, AICAR inhibited macrophage ER stress responses triggered by ER-stressors thapsigargin or tunicamycin. Surprisingly, AICAR acted independent of AMPK or AICAR conversion to 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranosyl monophosphate (ZMP) while requiring intracellular uptake via the equilibrative nucleoside transporter (ENT) ENT1 or the concentrative nucleoside transporter (CNT) CNT3. AICAR did not affect the initiation of the ER stress response, but inhibited the expression of major ER stress transcriptional effectors. Furthermore, AICAR inhibited autophosphorylation of the ER stress sensor inositol-requiring enzyme 1α (IRE1α), while activating its endoribonuclease activity in vitro. Our results suggest that AMPK-independent inhibition of ER stress responses contributes to anti-inflammatory and anti-diabetic effects of AICAR. PMID:27562249

  17. Extracytoplasmic Stress Responses Induced by Antimicrobial Cationic Polyethylenimines

    Lander, Blaine A.; Checchi, Kyle D.; Koplin, Stephen A.; Smith, Virginia F.; Domanski, Tammy L.; Isaac, Daniel D.; Lin, Shirley

    2012-01-01

    The ability of an antimicrobial, cationic polyethylenimine (PEI+) to induce the three known extracytoplasmic stress responses of Escherichia coli was quantified. Exposure of E. coli to PEI+ in solution revealed specific, concentration-dependent induction of the Cpx extracytoplasmic cellular stress response, ~2.0-2.5 fold at 320 μg/mL after 1.5 hours without significant induction of the σE or Bae stress responses. In comparison, exposure of E. coli to a non-antimicrobial polymer, polyethylene ...

  18. Stress Generation and Adolescent Depression: Contribution of Interpersonal Stress Responses

    Flynn, Megan; Rudolph, Karen D.

    2011-01-01

    This research examined the proposal that ineffective responses to common interpersonal problems disrupt youths' relationships, which, in turn, contributes to depression during adolescence. Youth (86 girls, 81 boys; M age = 12.41, SD = 1.19) and their primary female caregivers participated in a three-wave longitudinal study. Youth completed a…

  19. Stress Response and Translation Control in Rotavirus Infection

    López, Susana; Oceguera, Alfonso; Sandoval-Jaime, Carlos

    2016-01-01

    The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle. PMID:27338442

  20. Stress Response and Translation Control in Rotavirus Infection

    Susana López

    2016-06-01

    Full Text Available The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle.

  1. Stress Response and Translation Control in Rotavirus Infection.

    López, Susana; Oceguera, Alfonso; Sandoval-Jaime, Carlos

    2016-01-01

    The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle. PMID:27338442

  2. A Mycobacterium avium subsp. paratuberculosis Predicted Serine Protease Is Associated with Acid Stress and Intraphagosomal Survival.

    Kugadas, Abirami; Lamont, Elise A; Bannantine, John P; Shoyama, Fernanda M; Brenner, Evan; Janagama, Harish K; Sreevatsan, Srinand

    2016-01-01

    The ability to maintain intra-cellular pH is crucial for bacteria and other microbes to survive in diverse environments, particularly those that undergo fluctuations in pH. Mechanisms of acid resistance remain poorly understood in mycobacteria. Although, studies investigating acid stress in M. tuberculosis are gaining traction, few center on Mycobacterium avium subsp. paratuberculosis (MAP), the etiological agent of chronic enteritis in ruminants. We identified a MAP acid stress response network involved in macrophage infection. The central node of this network was MAP0403, a predicted serine protease that shared an 86% amino acid identity with MarP in M. tuberculosis. Previous studies confirmed MarP as a serine protease integral to maintaining intra-bacterial pH and survival in acid in vitro and in vivo. We show that MAP0403 is upregulated in infected macrophages and MAC-T cells that coincided with phagosome acidification. Treatment of mammalian cells with bafilomcyin A1, a potent inhibitor of phagosomal vATPases, diminished MAP0403 transcription. MAP0403 expression was also noted in acidic medium. A surrogate host, M. smegmatis mc(2) 155, was designed to express MAP0403 and when exposed to either macrophages or in vitro acid stress had increased bacterial cell viability, which corresponds to maintenance of intra-bacterial pH in acidic (pH = 5) conditions, compared to the parent strain. These data suggest that MAP0403 may be the equivalent of MarP in MAP. Future studies confirming MAP0403 as a serine protease and exploring its structure and possible substrates are warranted. PMID:27597934

  3. Regulation of dopamine system responsivity and its adaptive and pathological response to stress

    Belujon, Pauline; Grace, Anthony A.

    2015-01-01

    Although, historically, the norepinephrine system has attracted the majority of attention in the study of the stress response, the dopamine system has also been consistently implicated. It has long been established that stress plays a crucial role in the pathogenesis of psychiatric disorders. However, the neurobiological mechanisms that mediate the stress response and its effect in psychiatric diseases are not well understood. The dopamine system can play distinct roles in stress and psychiat...

  4. Antioxidant responses of wheat plants under stress

    Andréia Caverzan

    2016-03-01

    Full Text Available Abstract Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L., which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS, which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of ROS is sustained by enzymatic and nonenzymatic antioxidants. In the present review, we offer a brief summary of antioxidant defense and hydrogen peroxide (H2O2 signaling in wheat plants. Wheat plants increase antioxidant defense mechanisms under abiotic stresses, such as drought, cold, heat, salinity and UV-B radiation, to alleviate oxidative damage. Moreover, H2O2 signaling is an important factor contributing to stress tolerance in cereals.

  5. Antioxidant responses of wheat plants under stress.

    Caverzan, Andréia; Casassola, Alice; Brammer, Sandra Patussi

    2016-03-01

    Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L.), which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS), which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of ROS is sustained by enzymatic and nonenzymatic antioxidants. In the present review, we offer a brief summary of antioxidant defense and hydrogen peroxide (H2O2) signaling in wheat plants. Wheat plants increase antioxidant defense mechanisms under abiotic stresses, such as drought, cold, heat, salinity and UV-B radiation, to alleviate oxidative damage. Moreover, H2O2 signaling is an important factor contributing to stress tolerance in cereals. PMID:27007891

  6. Effects of regional analgesia on stress responses to pediatric surgery.

    Wolf, Andrew R

    2012-01-01

    Invasive surgery induces a combination of local response to tissue injury and generalized activation of systemic metabolic and hormonal pathways via afferent nerve pathways and the central nervous system. The local inflammatory responses and the parallel neurohumoral responses are not isolated but linked through complex signaling networks, some of which remain poorly understood. The magnitude of the response is broadly related to the site of injury (greater in regions with visceral pain afferents such as abdomen and thorax) and the extent of the trauma. The changes include alterations in metabolic, hormonal, inflammatory, and immune systems that can be collectively termed the stress response. Integral to the stress responses are the effects of nociceptive afferent stimuli on systemic and pulmonary vascular resistance, heart rate, and blood pressure, which are a combination of efferent autonomic response and catecholamine release via the adrenal medulla. Therefore, pain responses, cardiovascular responses, and stress responses need to be considered as different aspects of a combined bodily reaction to surgery and trauma. It is important at the outset to understand that not all components of the stress response are suppressed together and that this is important when discussing different analgesic modalities (i.e. opioids vs regional anesthesia). For example, in terms of the use of fentanyl in the infant, the dose required to provide analgesia (1-5 mcg·kg(-1)) is less than that required for hemodynamic stability in response to stimuli (5-10 mcg·kg(-1)) (1) and that this in turn is less than that required to suppress most aspects of the stress response (25-50 mcg·kg(-1)) (2). In contrast to this considerable dose dependency, central local anesthetic blocks allow blockade of the afferent and efferent sympathetic pathways at relatively low doses resulting in profound suppression of hemodynamic and stress responses to surgery. PMID:21999144

  7. Modulation of immune responses in stress by Yoga

    Arora Sarika; Bhattacharjee Jayashree

    2008-01-01

    Stress is a constant factor in today′s fastpaced life that can jeopardize our health if left unchecked. It is only in the last half century that the role of stress in every ailment from the common cold to AIDS has been emphasized, and the mechanisms involved in this process have been studied. Stress influences the immune response presumably through the activation of the hypothalamic-pituitary adrenal axis, hypothalamic pituitary-gonadal axis, and the sympathetic-adrenal-medullary syste...

  8. Protein phosphorylation in response to stress in Clostridium acetobutylicum.

    Balodimos, I A; Rapaport, E; Kashket, E R

    1990-01-01

    The possible involvement of protein phosphorylation in the clostridial stress response was investigated by radioactively labeling growing cells of Clostridium acetobutylicum with 32Pi or cell extracts with [gamma-32P]ATP. Several phosphoproteins were identified; these were not affected by the growth stage of the culture. Although the extent of protein phosphorylation was increased by heat stress, the phosphoproteins did not correspond to known stress proteins seen in one-dimensional sodium do...

  9. Sympathetic neural responses to mental stress during acute simulated microgravity

    Durocher, John J.; Schwartz, Christopher E.; Carter, Jason R.

    2009-01-01

    Neural and cardiovascular responses to mental stress and acute 6° head-down tilt (HDT) were examined separately and combined. We hypothesized sympathoexcitation during mental stress, sympathoinhibition during HDT, and an additive neural interaction during combined mental stress and HDT. Muscle sympathetic nerve activity (MSNA), mean arterial pressure (MAP), and heart rate (HR) were recorded in 16 healthy subjects (8 men, 8 women) in the supine position during three randomized trials: 1) menta...

  10. Boolean modeling and fault diagnosis in oxidative stress response

    Sridharan Sriram; Layek Ritwik; Datta Aniruddha; Venkatraj Jijayanagaram

    2012-01-01

    Abstract Background Oxidative stress is a consequence of normal and abnormal cellular metabolism and is linked to the development of human diseases. The effective functioning of the pathway responding to oxidative stress protects the cellular DNA against oxidative damage; conversely the failure of the oxidative stress response mechanism can induce aberrant cellular behavior leading to diseases such as neurodegenerative disorders and cancer. Thus, understanding the normal signaling present in ...

  11. Acute Stress Reduces Reward Responsiveness: Implications for Depression

    Bogdan, Ryan; Pizzagalli, Diego

    2006-01-01

    Background: Stress, one of the strongest risk factors for depression, has been linked to "anbedonic" behavior and dysfunctional reward-related neural circuitry in preclinical models. Methods: To test if acute stress reduces reward responsiveness (i.e., the ability to modulate behavior as a function of past reward), a signal-detection task coupled with a differential reinforcement schedule was utilized. Eighty female participants completed the task under both a stress condition, either threat-...

  12. The Teenage Brain: The Stress Response and the Adolescent Brain

    Romeo, Russell D.

    2013-01-01

    Adolescence is a time of many psychosocial and physiological changes. One such change is how an individual responds to stressors. Specifically, adolescence is marked by significant shifts in hypothalamic-pituitary-adrenal (HPA) axis reactivity, resulting in heightened stress-induced hormonal responses. It is presently unclear what mediates these changes in stress reactivity and what impacts they may have on an adolescent individual. However, stress-sensitive limbic and corti...

  13. Production of Polyamines Is Enhanced by Endogenous Abscisic Acid in Maize Seedlings Subjected to Salt Stress

    Jun LIU; Ming-Yi JIANG; Yi-Feng ZHOU; You-Liang LIU

    2005-01-01

    It is known that salt stress and exogenously applied abscisic acid (ABA) can enhance the polyamine content in plants and that salt stress itself can lead to an increase in endogenous ABA production.In the present study, the relationships between salt-induced ABA and polyamine accumulation were investigated using ABA-deficient mutant (vp5/vp5) maize (Zea mays L.) seedlings and ABA and polyamine :biosynthesis inhibitors. The results show that reduced endogenous ABA levels, as a result of either the mutation or by using a chemical inhibitor (sodium tungstate), also reduced the accumulation of polyamines in salt-stressed leaves of maize seedlings. The polyamine synthesis inhibitors D-arginine and αdifluoromethylornithine also reduced the polyamine content of the leaves of maize seedling under salt stress. Both ABA and polyamine enhanced the dry weight accumulation of salt-stressed seedlings and also increased the activities of the two dominant tonoplast membrane enzymes, H+-ATPase and H+-PPase, when plants were under salt stress. The results suggest that salt stress induces an increase in endogenous ABA levels, which then enhances polyamine synthesis. Such responses may increase a plant's tolerance to salt.

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

    Wang, Zhen-Yu

    2014-11-21

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

  15. Shared and unique responses of plants to multiple individual stresses and stress combinations: physiological and molecular mechanisms

    Pandey, Prachi; Ramegowda, Venkategowda; Senthil-Kumar, Muthappa

    2015-01-01

    In field conditions, plants are often simultaneously exposed to multiple biotic and abiotic stresses resulting in substantial yield loss. Plants have evolved various physiological and molecular adaptations to protect themselves under stress combinations. Emerging evidences suggest that plant responses to a combination of stresses are unique from individual stress responses. In addition, plants exhibit shared responses which are common to individual stresses and stress combination. In this rev...

  16. Personality, Stressful Life Events, and Treatment Response in Major Depression

    Bulmash, Eric; Harkness, Kate L.; Stewart, Jeremy G.; Bagby, R. Michael

    2009-01-01

    The current study examined whether the personality traits of self-criticism or dependency moderated the effect of stressful life events on treatment response. Depressed outpatients (N = 113) were randomized to 16 weeks of cognitive-behavioral therapy, interpersonal psychotherapy, or antidepressant medication (ADM). Stressful life events were…

  17. Are karrikins involved in plant abiotic stress responses?

    Li, Weiqiang; Tran, Lam-Son Phan

    2015-09-01

    Recent reports have shown that strigolactones play a positive role in plant responses to drought and salt stress through MAX2 (More Axillary Growth 2). Increasing evidence suggests that MAX2 is also involved in karrikin signaling, raising the question whether karrikins play any role in plant adaptation to abiotic stresses. PMID:26255855

  18. Traumatic Experience in Infancy: How Responses to Stress Affect Development

    Witten, Molly Romer

    2010-01-01

    Responses to traumatic stress during the earliest years of life can change quickly and can be difficult to identify because of the young child's rapid rate of development. The symptoms of traumatic stress will depend on the child's developmental level and individual coping styles, as well as the quality and nature of the child's most important…

  19. Differentiating anticipatory from reactive cortisol responses to psychosocial stress

    Engert, V.; Efanov, S.I.; Duchesne, A.; Vogel, S.; Corbo, V.; Pruessner, J.C.

    2013-01-01

    Most psychosocial stress studies assess the overall cortisol response without further identifying the temporal dynamics within hormone levels. It has been shown, however, that the amplitude of anticipatory cortisol stress levels has a unique predictive value for psychological health. So far, no "bes

  20. Quorum Sensing Enhances the Stress Response in Vibrio cholerae▿

    Joelsson, Adam; Kan, Biao; Jun ZHU

    2007-01-01

    Vibrio cholerae lives in aquatic environments and causes cholera. Here, we show that quorum sensing enhances V. cholerae viability under certain stress conditions by upregulating the expression of RpoS, and this regulation acts through HapR, suggesting that a quorum-sensing-enhanced stress response plays a role in V. cholerae environmental survival.

  1. Oxidative stress response pathways: Fission yeast as archetype

    Papadakis, Manos A.; Workman, Christopher

    2015-01-01

    Schizosaccharomyces pombe is a popular model eukaryotic organism to study diverse aspects of mammalian biology, including responses to cellular stress triggered by redox imbalances within its compartments. The review considers the current knowledge on the signaling pathways that govern the...

  2. [The effect of stressor experiences and optimism upon stress responses].

    Tonan, K; Sonoda, A

    1994-10-01

    The present studies investigated whether or not optimism/pessimism is a cognitive mediator of future depression for people who have experienced many negative life events. Subjects were administered optimism scales, stress response scales at Time 1. They then completed the stressor scale and stress response scales at Time 2, about six weeks later. The results showed the interaction of stressor experiences and optimistic diathesis: Subjects who have higher stressor experiences and higher stable and global explanatory style for negative events showed higher depressive responses. Other indices of optimistic diathesis--Life Orientation, Cognitive Style, and Internality dimension of Attributional Style--did not produce this interaction effect. Moreover, this interaction did not appear in the psychological stress response other than depression. These results were consistent with diathesis-stress model of depression. PMID:7861687

  3. STIFDB2: An Updated Version of Plant Stress-Responsive TranscrIption Factor DataBase with Additional Stress Signals, Stress-Responsive Transcription Factor Binding Sites and Stress-Responsive Genes in Arabidopsis and Rice

    Naika, Mahantesha; Shameer, Khader; Mathew, Oommen K; Gowda, Ramanjini; Sowdhamini, Ramanathan

    2013-01-01

    Understanding the principles of abiotic and biotic stress responses, tolerance and adaptation remains important in plant physiology research to develop better varieties of crop plants. Better understanding of plant stress response mechanisms and application of knowledge derived from integrated experimental and bioinformatics approaches are gaining importance. Earlier, we showed that compiling a database of stress-responsive transcription factors and their corresponding target binding sites in...

  4. Selection for intrinsic endurance modifies endocrine stress responsiveness

    Waters, R Parrish; Renner, Kenneth J.; Summers, Cliff H.; Watt, Michael L; Forster, Gina L.; Koch, Lauren G.; Britton, Steven L.; Swallow, John G.

    2010-01-01

    Physical exercise dampens an individual’s stress response and decreases symptoms of anxiety and depression disorders. While the extrinsic relationship of exercise and psychological state are established, their intrinsic relationship is unresolved. We investigated the potential intrinsic relationship of exercise with stress responsiveness using NIH rats bidirectionally selected for intrinsic endurance capacity. Selection resulted in two populations, one with high intrinsic endurance (high capa...

  5. Context and strain-dependent behavioral response to stress

    Baum Amber E

    2008-06-01

    Full Text Available Abstract Background This study posed the question whether strain differences in stress-reactivity lead to differential behavioral responses in two different tests of anxiety. Strain differences in anxiety-measures are known, but strain differences in the behavioral responses to acute prior stress are not well characterized. Methods We studied male Fisher 344 (F344 and Wistar Kyoto (WKY rats basally and immediately after one hour restraint stress. To distinguish between the effects of novelty and prior stress, we also investigated behavior after repeated exposure to the test chamber. Two behavioral tests were explored; the elevated plus maze (EPM and the open field (OFT, both of which are thought to measure activity, exploration and anxiety-like behaviors. Additionally, rearing, a voluntary behavior, and grooming, a relatively automatic, stress-responsive stereotyped behavior were measured in both tests. Results Prior exposure to the test environment increased anxiety-related measures regardless of prior stress, reflecting context-dependent learning process in both tests and strains. Activity decreased in response to repeated testing in both tests and both strains, but prior stress decreased activity only in the OFT which was reversed by repeated testing. Prior stress decreased anxiety-related measures in the EPM, only in F344s, while in the OFT, stress led to increased freezing mainly in WKYs. Conclusion Data suggest that differences in stressfulness of these tests predict the behavior of the two strains of animals according to their stress-reactivity and coping style, but that repeated testing can overcome some of these differences.

  6. Low-stress and high-stress singing have contrasting effects on glucocorticoid response

    Daisy eFancourt

    2015-09-01

    Full Text Available Performing music in public is widely recognised as a potentially stress-inducing activity. However, despite the interest in music performance as an acute psychosocial stressor, there has been relatively little research on the effects of public performance on the endocrine system. This study examined the impact of singing in a low-stress performance situation and a high-stress live concert on levels of glucocorticoids (cortisol and cortisone in 15 professional singers. The results showed a significant decrease in both cortisol and cortisone across the low-stress condition, suggesting that singing in itself is a stress-reducing (and possibly health-promoting activity, but significant increases across the high-stress condition. This is the first study to demonstrate that singing affects glucocorticoid responses and that these responses are modulated by the conditions of performance.

  7. Low-stress and high-stress singing have contrasting effects on glucocorticoid response.

    Fancourt, Daisy; Aufegger, Lisa; Williamon, Aaron

    2015-01-01

    Performing music in public is widely recognized as a potentially stress-inducing activity. However, despite the interest in music performance as an acute psychosocial stressor, there has been relatively little research on the effects of public performance on the endocrine system. This study examined the impact of singing in a low-stress performance situation and a high-stress live concert on levels of glucocorticoids (cortisol and cortisone) in 15 professional singers. The results showed a significant decrease in both cortisol and cortisone across the low-stress condition, suggesting that singing in itself is a stress-reducing (and possibly health-promoting) activity, but significant increases across the high-stress condition. This is the first study to demonstrate that singing affects cortisol as well as cortisone responses and that these responses are modulated by the conditions of performance. PMID:26388794

  8. Roles of Hsp70s in Stress Responses of Microorganisms, Plants, and Animals

    Anmin Yu

    2015-01-01

    Full Text Available Hsp70s (heat shock protein 70s are a class of molecular chaperones that are highly conserved and ubiquitous in organisms ranging from microorganisms to plants and humans. Most research on Hsp70s has focused on the mechanisms of their functions as molecular chaperones, but recently, studies on stress responses are coming to the forefront. Hsp70s play key roles in cellular development and protecting living organisms from environmental stresses such as heat, drought, salinity, acidity, and cold. Moreover, functions of human Hsp70s are related to diseases including neurological disorders, cancer, and virus infection. In this review, we provide an overview of the specific roles of Hsp70s in response to stress, particularly abiotic stress, in all living organisms.

  9. When does stress help or harm? The effects of stress controllability and subjective stress response on Stroop performance.

    Roselinde Kaiser Henderson

    2012-06-01

    Full Text Available The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing to clinical therapy. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low responses can lead to impaired performance. The present studies tested the hypothesis that 1 learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that 2 this improvement emerges specifically for people who report moderate (subjective responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n=109. People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n=90, we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress

  10. Antioxidant responses of wheat plants under stress

    Andréia Caverzan; Alice Casassola; Sandra Patussi Brammer

    2016-01-01

    Abstract Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L.), which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS), which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of RO...

  11. The role of the HvNAC6 transcription factor in response to biotic and abiotic stress in barley

    Chen, Yan-Jun

    -mediated transformation methods could be used to study stress responses at the whole-plant level. The abscisic acid (ABA) and salicylic acid (SA) levels were measured during Bgh infection to investigate the involvement of these hormones and TF in the basal resistance. HvNAC6 RNAi plants were also subjected to dehydration...

  12. Recent Molecular Advances on Downstream Plant Responses to Abiotic Stress

    Cláudia Regina Batista de Souza

    2012-07-01

    Full Text Available Abiotic stresses such as extremes of temperature and pH, high salinity and drought, comprise some of the major factors causing extensive losses to crop production worldwide. Understanding how plants respond and adapt at cellular and molecular levels to continuous environmental changes is a pre-requisite for the generation of resistant or tolerant plants to abiotic stresses. In this review we aimed to present the recent advances on mechanisms of downstream plant responses to abiotic stresses and the use of stress-related genes in the development of genetically engineered crops.

  13. The response of Paracoccus sp. SKG to acetonitrile-induced oxidative stress.

    Kirankumar, B; Guruprasad, B Kulkarni; Santoshkumar, M; Anand, S Nayak; Karegoudar, T B

    2013-11-01

    Organic solvents enhance intracellular oxidative stress and induce various physiological responses in bacteria. The study shows the morphological changes in Paracoccus sp. SKG when exposed to higher concentrations of acetonitrile, which alter the composition of the membrane fatty acid that accompanies the increase in K(+) efflux. This enhances the oxidative stress with greater activities of catalase and super oxide dismutase (SOD). The increased oxidative stress results in the generation of free radicals, which was confirmed by electron paramagnetic resonance (EPR) studies. The free radical scavenging activities were measured by ABTS and DPPH to understand the non-enzymatic defensive system during oxidative stress. The studies demonstrate the increase in free radicals in association with enzymatic and non-enzymatic defense systems under solvent stress. PMID:24092001

  14. Stress-buffering effects of psychosocial resources on physiological and psychological stress response in pregnant women

    Nierop, Ada; Wirtz, Petra H; Bratsikas, Aliki; Zimmermann, Roland; Ehlert, Ulrike

    2008-01-01

    Sixty healthy pregnant women (aged 21-35 years), including 30 pregnant women at the beginning of second trimester and 30 women at the beginning of third trimester underwent a psychosocial stress test. Physiological (salivary free cortisol levels, salivary alpha-amylase levels) and psychological (perceived stress, mood, anxiety) responses to standardized psychosocial stress have been brought in association with psychosocial resources (self-efficacy and daily uplifts). Predictions revealed that...

  15. Arbuscular mycorrhizal fungal responses to abiotic stresses: A review.

    Lenoir, Ingrid; Fontaine, Joël; Lounès-Hadj Sahraoui, Anissa

    2016-03-01

    The majority of plants live in close collaboration with a diversity of soil organisms among which arbuscular mycorrhizal fungi (AMF) play an essential role. Mycorrhizal symbioses contribute to plant growth and plant protection against various environmental stresses. Whereas the resistance mechanisms induced in mycorrhizal plants after exposure to abiotic stresses, such as drought, salinity and pollution, are well documented, the knowledge about the stress tolerance mechanisms implemented by the AMF themselves is limited. This review provides an overview of the impacts of various abiotic stresses (pollution, salinity, drought, extreme temperatures, CO2, calcareous, acidity) on biodiversity, abundance and development of AMF and examines the morphological, biochemical and molecular mechanisms implemented by AMF to survive in the presence of these stresses. PMID:26803396

  16. Transcriptome Sequencing in Response to Salicylic Acid in Salvia miltiorrhiza.

    Zhang, Xiaoru; Dong, Juane; Liu, Hailong; Wang, Jiao; Qi, Yuexin; Liang, Zongsuo

    2016-01-01

    Salvia miltiorrhiza is a traditional Chinese herbal medicine, whose quality and yield are often affected by diseases and environmental stresses during its growing season. Salicylic acid (SA) plays a significant role in plants responding to biotic and abiotic stresses, but the involved regulatory factors and their signaling mechanisms are largely unknown. In order to identify the genes involved in SA signaling, the RNA sequencing (RNA-seq) strategy was employed to evaluate the transcriptional profiles in S. miltiorrhiza cell cultures. A total of 50,778 unigenes were assembled, in which 5,316 unigenes were differentially expressed among 0-, 2-, and 8-h SA induction. The up-regulated genes were mainly involved in stimulus response and multi-organism process. A core set of candidate novel genes coding SA signaling component proteins was identified. Many transcription factors (e.g., WRKY, bHLH and GRAS) and genes involved in hormone signal transduction were differentially expressed in response to SA induction. Detailed analysis revealed that genes associated with defense signaling, such as antioxidant system genes, cytochrome P450s and ATP-binding cassette transporters, were significantly overexpressed, which can be used as genetic tools to investigate disease resistance. Our transcriptome analysis will help understand SA signaling and its mechanism of defense systems in S. miltiorrhiza. PMID:26808150

  17. Sex differences in the stress response in SD rats.

    Lu, Jing; Wu, Xue-Yan; Zhu, Qiong-Bin; Li, Jia; Shi, Li-Gen; Wu, Juan-Li; Zhang, Qi-Jun; Huang, Man-Li; Bao, Ai-Min

    2015-05-01

    Sex differences play an important role in depression, the basis of which is an excessive stress response. We aimed at revealing the neurobiological sex differences in the same study in acute- and chronically-stressed rats. Female Sprague-Dawley (SD) rats were randomly divided into 6 groups: chronic unpredictable mild stress (CUMS), acute foot shock (FS) and controls, animals in all 3 groups were sacrificed in proestrus or diestrus. Male SD rats were randomly divided into 3 groups: CUMS, FS and controls. Comparisons were made of behavioral changes in CUMS and control rats, plasma levels of corticosterone (CORT), testosterone (T) and estradiol (E2), and of the hypothalamic mRNA-expression of stress-related molecules, i.e. estrogen receptor α and β, androgen receptor, aromatase, mineralocorticoid receptor, glucocorticoid receptor, corticotropin-releasing hormone, arginine vasopressin and oxytocin. CUMS resulted in disordered estrus cycles, more behavioral and hypothalamic stress-related molecules changes and a stronger CORT response in female rats compared with male rats. Female rats also showed decreased E2 and T levels after FS and CUMS, while male FS rats showed increased E2 and male CUMS rats showed decreased T levels. Stress affects the behavioral, endocrine and the molecular response of the stress systems in the hypothalamus of SD rats in a clear sexual dimorphic way, which has parallels in human data on stress and depression. PMID:25687843

  18. Modulation of immune responses in stress by Yoga

    Arora Sarika

    2008-01-01

    Full Text Available Stress is a constant factor in today′s fastpaced life that can jeopardize our health if left unchecked. It is only in the last half century that the role of stress in every ailment from the common cold to AIDS has been emphasized, and the mechanisms involved in this process have been studied. Stress influences the immune response presumably through the activation of the hypothalamic-pituitary adrenal axis, hypothalamic pituitary-gonadal axis, and the sympathetic-adrenal-medullary system. Various neurotransmitters, neuropeptides, hormones, and cytokines mediate these complex bidirectional interactions between the central nervous system (CNS and the immune system. The effects of stress on the immune responses result in alterations in the number of immune cells and cytokine dysregulation. Various stress management strategies such as meditation, yoga, hypnosis, and muscle relaxation have been shown to reduce the psychological and physiological effects of stress in cancers and HIV infection. This review aims to discuss the effect of stress on the immune system and examine how relaxation techniques such as Yoga and meditation could regulate the cytokine levels and hence, the immune responses during stress.

  19. Genes Acting on Transcriptional Control during Abiotic Stress Responses

    Glacy Jaqueline da Silva

    2014-01-01

    Full Text Available Abiotic stresses are the major cause of yield loss in crops around the world. Greater genetic gains are possible by combining the classical genetic improvement with advanced molecular biology techniques. The understanding of mechanisms triggered by plants to meet conditions of stress is of fundamental importance for the elucidation of these processes. Current genetically modified crops help to mitigate the effects of these stresses, increasing genetic gains in order to supply the agricultural market and the demand for better quality food throughout the world. To obtain safe genetic modified organisms for planting and consumption, a thorough grasp of the routes and genes that act in response to these stresses is necessary. This work was developed in order to collect important information about essential TF gene families for transcriptional control under abiotic stress responses.

  20. Arabidopsis Non-Coding RNA Regulation in Abiotic Stress Responses

    Akihiro Matsui

    2013-11-01

    Full Text Available Plant growth and productivity are largely affected by environmental stresses. Therefore, plants have evolved unique adaptation mechanisms to abiotic stresses through fine-tuned adjustment of gene expression and metabolism. Recent advanced technologies, such as genome-wide transcriptome analysis, have revealed that a vast amount of non-coding RNAs (ncRNAs apart from the well-known housekeeping ncRNAs such as rRNAs, tRNAs, small nuclear RNAs (snRNAs and small nucleolar RNAs (snoRNAs are expressed under abiotic stress conditions. These various types of ncRNAs are involved in chromatin regulation, modulation of RNA stability and translational repression during abiotic stress response. In this review, we summarize recent progress that has been made on ncRNA research in plant abiotic stress response.

  1. Stressed out? Associations between perceived and physiological stress responses in adolescents : The TRAILS study

    Oldehinkel, Albertine J.; Ormel, Johan; Bosch, Nienke M.; Bouma, Esther M. C.; Van Roon, Arie M.; Rosmalen, Judith G. M.; Riese, Harriette

    2011-01-01

    Studies regarding the interrelation of perceived and physiological stress indices have shown diverging results. Using a population sample of adolescents (N=715, 50.9% girls, mean age 16.11 years, SD=0.59), we tested three hypotheses: (1) perceived responses during social stress covary with concurren

  2. Crop and medicinal plants proteomics in response to salt stress

    Keyvan eAghaei

    2013-01-01

    Full Text Available Increasing of world population marks a serious need to create new crop cultivars and medicinal plants with high growth and production at any environmental situations. Among the environmental unfavorable conditions, salinity is the most widespread in the world. Crop production and growth severely decreases under salt stress; however, some crop cultivars show significant tolerance against the negative effects of salinity. Among salt stress responses of crops, proteomic responses play a pivotal role in their ability to cope with it and have become the main center of notification. Many physiological responses are detectable in terms of protein increase and decrease even before physiological responses take place. Thus proteomic approach makes a short cut in the way of inferring how crops response to salt stress. Nowadays many salt-responsive proteins such as heat shock proteins, pathogen related proteins, protein kinases, ascorbate peroxidase, osmotin, ornithine decarboxylase and some transcription factors, have been detected in some major crops which are thought to give them the ability of withstanding against salt stress. Proteomic analysis of medicinal plants also revealed that alkaloid biosynthesis related proteins such as tryptophan synthase, codeinone reductase, strictosidine synthase and 12-oxophytodienoate reductase might have major role in production of secondary metabolites. In this review we are comparing some different or similar proteomic responses of several crops and medicinal plants to salt stress and discuss about the future prospects.

  3. Crop and medicinal plants proteomics in response to salt stress.

    Aghaei, Keyvan; Komatsu, Setsuko

    2013-01-01

    Increasing of world population marks a serious need to create new crop cultivars and medicinal plants with high growth and production at any environmental situations. Among the environmental unfavorable conditions, salinity is the most widespread in the world. Crop production and growth severely decreases under salt stress; however, some crop cultivars show significant tolerance against the negative effects of salinity. Among salt stress responses of crops, proteomic responses play a pivotal role in their ability to cope with it and have become the main center of notification. Many physiological responses are detectable in terms of protein increase and decrease even before physiological responses take place. Thus proteomic approach makes a short cut in the way of inferring how crops response to salt stress. Nowadays many salt-responsive proteins such as heat shock proteins, pathogen-related proteins, protein kinases, ascorbate peroxidase, osmotin, ornithine decarboxylase, and some transcription factors, have been detected in some major crops which are thought to give them the ability of withstanding against salt stress. Proteomic analysis of medicinal plants also revealed that alkaloid biosynthesis related proteins such as tryptophan synthase, codeinone reductase, strictosidine synthase, and 12-oxophytodienoate reductase might have major role in production of secondary metabolites. In this review we are comparing some different or similar proteomic responses of several crops and medicinal plants to salt stress and discuss about the future prospects. PMID:23386857

  4. Plant Responses to Simultaneous Biotic and Abiotic Stress: Molecular Mechanisms

    Ines Ben Rejeb

    2014-10-01

    Full Text Available Plants are constantly confronted to both abiotic and biotic stresses that seriously reduce their productivity. Plant responses to these stresses are complex and involve numerous physiological, molecular, and cellular adaptations. Recent evidence shows that a combination of abiotic and biotic stress can have a positive effect on plant performance by reducing the susceptibility to biotic stress. Such an interaction between both types of stress points to a crosstalk between their respective signaling pathways. This crosstalk may be synergistic and/or antagonistic and include among others the involvement of phytohormones, transcription factors, kinase cascades, and reactive oxygen species (ROS. In certain cases, such crosstalk can lead to a cross-tolerance and enhancement of a plant’s resistance against pathogens. This review aims at giving an insight into cross-tolerance between abiotic and biotic stress, focusing on the molecular level and regulatory pathways.

  5. Metabolic changes in Citrus leaf volatiles in response to environmental stress.

    Asai, Tomonori; Matsukawa, Tetsuya; Kajiyama, Shin'ichiro

    2016-02-01

    Citrus plants are well known as a rich source of VOCs, and several have important roles in defense responses. However, how VOCs are regulated in response to environmental stress is not yet well understood. In this study, we investigated dynamic changes of VOCs present in leaves of seven Citrus species (Citrus sinensis, C. limon, C. paradisi, C. unshiu, C. kinokuni, C. grandis, and C. hassaku) in response to mechanical wounding, jasmonic acid (JA), and salicylic acid (SA) as determined by gas chromatography/mass spectrometric analysis followed by multivariate analysis (principal component analysis, PCA, and orthogonal partial least squares-discriminant analysis, OPLS-DA). PCA and OPLS-DA suggested that changes in VOC profiles against stress stimuli were much diverse among Citrus species. OPLS-DA showed that C6 volatiles, such as hexanal and trans-2-hexenal, were induced in response to JA and SA stimuli in C. sinensis and C. grandis, while the other VOCs were decreased under all tested stress conditions. α-Farnesene was induced in all species except C. hassaku after wounding or JA treatment. In addition, α-farnesene was also induced in response to SA stimuli in C. unshiu and C. kinokuni. Therefore these volatiles can be candidates of the common stress biomarkers in Citrus. Our results will give a new insight into defense mechanisms in Citrus species. PMID:26188419

  6. Effects of oxidative stress on fatty acid- and one-carbon-metabolism in psychiatric and cardiovascular disease comorbidity

    Assies, J.; Mocking, R J T; Lok, A; Ruhé, H.G.; Pouwer, F.; Schene, A. H.

    2014-01-01

    Objective Cardiovascular disease (CVD) is the leading cause of death in severe psychiatric disorders (depression, schizophrenia). Here, we provide evidence of how the effects of oxidative stress on fatty acid (FA) and one-carbon (1-C) cycle metabolism, which may initially represent adaptive responses, might underlie comorbidity between CVD and psychiatric disorders. Method We conducted a literature search and integrated data in a narrative review. Results Oxidative stress, mainly generated in...

  7. The surgical stress response: should it be prevented?

    Kehlet, H

    1991-01-01

    suppress the detrimental components of the stress response so as to improve postoperative outcome. Of the various techniques to reduce the surgical stress response, afferent neural blockade with regional anesthesia to relieve pain is the most effective, although not optimal. Data from numerous controlled......Postoperative complications such as myocardial infarction, pulmonary infection, thromboembolism and fatigue are probably related to increased demands, hypermetabolism, catabolism and other physiologic changes included in the global "surgical stress response." Strategies have been developed to...... clinical trials have demonstrated a reduction in various aspects of postoperative morbidity by such a nociceptive blockade. Although a causal relationship has still to be demonstrated, these findings strongly argue the concept of "stress-free anesthesia and surgery" as an important instrument in improving...

  8. Plant transcriptomics and responses to environmental stress: an overview

    Sameen Ruqia Imadi; Alvina Gul Kazi; Mohammad Abass Ahanger; Salih Gucel; Parvaiz Ahmad

    2015-09-01

    Different stresses include nutrient deficiency, pathogen attack, exposure to toxic chemicals etc. Transcriptomic studies have been mainly applied to only a few plant species including the model plant, Arabidopsis thaliana. These studies have provided valuable insights into the genetic networks of plant stress responses. Transcriptomics applied to cash crops including barley, rice, sugarcane, wheat and maize have further helped in understanding physiological and molecular responses in terms of genome sequence, gene regulation, gene differentiation, posttranscriptional modifications and gene splicing. On the other hand, comparative transcriptomics has provided more information about plant’s response to diverse stresses. Thus, transcriptomics, together with other biotechnological approaches helps in development of stress tolerance in crops against the climate change.

  9. Chloroplast Retrograde Regulation of Heat Stress Responses in Plants.

    Sun, Ai-Zhen; Guo, Fang-Qing

    2016-01-01

    It is well known that intracellular signaling from chloroplast to nucleus plays a vital role in stress responses to survive environmental perturbations. The chloroplasts were proposed as sensors to heat stress since components of the photosynthetic apparatus housed in the chloroplast are the major targets of thermal damage in plants. Thus, communicating subcellular perturbations to the nucleus is critical during exposure to extreme environmental conditions such as heat stress. By coordinating expression of stress specific nuclear genes essential for adaptive responses to hostile environment, plants optimize different cell functions and activate acclimation responses through retrograde signaling pathways. The efficient communication between plastids and the nucleus is highly required for such diverse metabolic and biosynthetic functions during adaptation processes to environmental stresses. In recent years, several putative retrograde signals released from plastids that regulate nuclear genes have been identified and signaling pathways have been proposed. In this review, we provide an update on retrograde signals derived from tetrapyrroles, carotenoids, reactive oxygen species (ROS) and organellar gene expression (OGE) in the context of heat stress responses and address their roles in retrograde regulation of heat-responsive gene expression, systemic acquired acclimation, and cellular coordination in plants. PMID:27066042

  10. Bacillus cereus cell response upon exposure to acid environment: towards the identification of potential biomarkers

    Noémie eDESRIAC

    2013-10-01

    Full Text Available Microorganisms are able to adapt to different environments and evolve rapidly, allowing them to cope with their new environments. Such adaptive response and associated protections towards other lethal stresses, is a crucial survival strategy for a wide spectrum of microorganisms, including food spoilage bacteria, pathogens and organisms used in functional food applications. The growing demand for minimal processed food yields to an increasing use of combination of hurdles or mild preservation factors in the food industry. A commonly used hurdle is low pH which allows the decrease in bacterial growth rate but also the inactivation of pathogens or spoilage microorganisms. Bacillus cereus is a well-known food-borne pathogen leading to economical and safety issues in food industry. Because survival mechanisms implemented will allow bacteria to cope with environmental changes, it is important to provide understanding of B. cereus stress response. Thus this review deals with the adaptive traits of B. cereus cells facing to acid stress conditions. The acid stress response of B. cereus could be divided into four groups (i general stress response (ii pH homeostasis, (iii metabolic modifications and alkali production and (iv secondary oxidative stress response. This current knowledge may be useful to understand how B. cereus cells may cope to acid environment such as encountered in food products and thus to find some molecular biomarkers of the bacterial behaviour. These biomarkers could be furthermore used to develop new microbial behaviour prediction tools which can provide insights into underlying molecular physiological states which govern the behaviour of microorganisms and thus opening the avenue toward the detection of stress adaptive behaviour at an early stage and the control of stress-induced resistance throughout the food chain.

  11. Bacillus cereus cell response upon exposure to acid environment: toward the identification of potential biomarkers.

    Desriac, Noémie; Broussolle, Véronique; Postollec, Florence; Mathot, Anne-Gabrielle; Sohier, Danièle; Coroller, Louis; Leguerinel, Ivan

    2013-01-01

    Microorganisms are able to adapt to different environments and evolve rapidly, allowing them to cope with their new environments. Such adaptive response and associated protections toward other lethal stresses, is a crucial survival strategy for a wide spectrum of microorganisms, including food spoilage bacteria, pathogens, and organisms used in functional food applications. The growing demand for minimal processed food yields to an increasing use of combination of hurdles or mild preservation factors in the food industry. A commonly used hurdle is low pH which allows the decrease in bacterial growth rate but also the inactivation of pathogens or spoilage microorganisms. Bacillus cereus is a well-known food-borne pathogen leading to economical and safety issues in food industry. Because survival mechanisms implemented will allow bacteria to cope with environmental changes, it is important to provide understanding of B. cereus stress response. Thus this review deals with the adaptive traits of B. cereus cells facing to acid stress conditions. The acid stress response of B. cereus could be divided into four groups (i) general stress response (ii) pH homeostasis, (iii) metabolic modifications and alkali production and (iv) secondary oxidative stress response. This current knowledge may be useful to understand how B. cereus cells may cope to acid environment such as encountered in food products and thus to find some molecular biomarkers of the bacterial behavior. These biomarkers could be furthermore used to develop new microbial behavior prediction tools which can provide insights into underlying molecular physiological states which govern the behavior of microorganisms and thus opening the avenue toward the detection of stress adaptive behavior at an early stage and the control of stress-induced resistance throughout the food chain. PMID:24106490

  12. Molecular and biochemical responses of Volvox carteri to oxidative stress

    Lingappa, U.; Rankin-Gee, E. K.; Lera, M.; Bebour, B.; Marcu, O.

    2014-03-01

    Understanding the intracellular response to environmental stresses is a key aspect to understanding the limits of habitability for life as we know it. A wide range of relevant stressors, from heat shock to radiation, result in the intracellular production of reactive oxygen species (ROS). ROS are used physiologically as signaling molecules to cause changes in gene expression and metabolism. However, ROS, including superoxide (O2-) and peroxides, are also highly reactive molecules that cause oxidative damage to proteins, lipids and DNA. Here we studied stress response in the multicellular, eukaryotic green alga Volvox carteri, after exposure to heat shock conditions. We show that the ROS response to heat stress is paralleled by changes in photosynthetic metabolism, antioxidant enzyme activity and gene expression, and fluctuations in the elemental composition of cells. Metabolism, as measured by pulse amplitude modulated (PAM) fluorometry over two hours of heat stress, showed a linear decrease in the photosynthetic efficiency of Volvox. ROS quantification uncovered an increase in ROS in the culture medium, paralleled by a decrease in ROS within the Volvox colonies, suggesting an export mechanism is utilized to mitigate stress. Enzyme kinetics indicated an increase in superoxide dismutase (SOD) activity over the heat stress timecourse. Using X-ray fluorescence (XRF) at the Stanford Synchrotron Radiation Lightsource, we show that these changes coincide with cell-specific import/export and intracellular redistribution of transition elements and halides, suggesting that the cellular metallome is also engaged in mediating oxidative stress in Volvox.

  13. Fresh green tea and gallic acid ameliorate oxidative stress in kainic acid-induced status epilepticus.

    Huang, Hsiao-Ling; Lin, Chih-Cheng; Jeng, Kee-Ching G; Yao, Pei-Wun; Chuang, Lu-Te; Kuo, Su-Ling; Hou, Chien-Wei

    2012-03-01

    Green tea is one of the most-consumed beverages due to its taste and antioxidative polyphenols. However, the protective effects of green tea and its constituent, gallic acid (GA), against kainic acid (KA)-induced seizure have not been studied. We investigated the effect of fresh green tea leaf (GTL) and GA on KA-induced neuronal injury in vivo and in vitro. The results showed that GTL and GA reduced the maximal seizure classes, predominant behavioral seizure patterns, and lipid peroxidation in male FVB mice with status epilepticus (SE). GTL extract and GA provided effective protection against KA-stressed PC12 cells in a dose-dependent manner. In the protective mechanism study, GTL and GA decreased Ca(2+) release, ROS, and lipid peroxidation from KA-stressed PC12 cells. Western blot results revealed that mitogen-activated protein kinases (MAPKs), RhoA, and COX-2 expression were increased in PC12 cells under KA stress, and expression of COX-2 and p38 MAPK, but not RhoA, was significantly reduced by GTL and GA. Furthermore, GTL and GA were able to reduce PGE(2) production from KA-stressed PC12 cells. Taken together, the results showed that GTL and GA provided neuroprotective effects against excitotoxins and may have a clinical application in epilepsy. PMID:22324774

  14. Oxidative stress impairs the heat stress response and delays unfolded protein recovery.

    Masaaki Adachi

    Full Text Available BACKGROUND: Environmental changes, air pollution and ozone depletion are increasing oxidative stress, and global warming threatens health by heat stress. We now face a high risk of simultaneous exposure to heat and oxidative stress. However, there have been few studies investigating their combined adverse effects on cell viability. PRINCIPAL FINDINGS: Pretreatment of hydrogen peroxide (H(2O(2 specifically and highly sensitized cells to heat stress, and enhanced loss of mitochondrial membrane potential. H(2O(2 exposure impaired the HSP40/HSP70 induction as heat shock response (HSR and the unfolded protein recovery, and enhanced eIF2alpha phosphorylation and/or XBP1 splicing, land marks of ER stress. These H(2O(2-mediated effects mimicked enhanced heat sensitivity in HSF1 knockdown or knockout cells. Importantly, thermal preconditioning blocked H(2O(2-mediated inhibitory effects on refolding activity and rescued HSF1 +/+ MEFs, but neither blocked the effects nor rescued HSF1 -/- MEFs. These data strongly suggest that inhibition of HSR and refolding activity is crucial for H(2O(2-mediated enhanced heat sensitivity. CONCLUSIONS: H(2O(2 blocks HSR and refolding activity under heat stress, thereby leading to insufficient quality control and enhancing ER stress. These uncontrolled stress responses may enhance cell death. Our data thus highlight oxidative stress as a crucial factor affecting heat tolerance.

  15. Keratins Are Altered in Intestinal Disease-Related Stress Responses.

    Helenius, Terhi O; Antman, Cecilia A; Asghar, Muhammad Nadeem; Nyström, Joel H; Toivola, Diana M

    2016-01-01

    Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery. PMID:27626448

  16. Effects of d-amphetamine upon psychosocial stress responses.

    Childs, Emma; Bershad, Anya K; de Wit, Harriet

    2016-07-01

    Psychostimulant drugs alter the salience of stimuli in both laboratory animals and humans. In animals, stimulants increase rates of responding to conditioned incentive stimuli, and in humans, amphetamine increases positive ratings of emotional images. However, the effects of stimulants on real-life emotional events have not been studied in humans. In this study, we examined the effect of d-amphetamine on responses to acute psychosocial stress using a public speaking task. Healthy volunteers (N=56) participated in two experimental sessions, one with a psychosocial stressor (the Trier Social Stress Test) and one with a non-stressful control task. They were randomly assigned to receive d-amphetamine (5 mg n=18, 10 mg n=20) or placebo (n=18) on both sessions under double blind conditions. Salivary cortisol, subjective mood, and vital signs were measured at regular intervals during the session. Subjects also provided cognitive appraisals of the tasks before and after their performances. Amphetamine produced its expected mood and physiological effects, and the Trier Social Stress Test produced its expected effects on cortisol and mood. Although neither dose of amphetamine altered cardiovascular or hormonal responses to stress, amphetamine (10 mg) increased participants' pre-task appraisals of how challenging the task would be, and it increased post-task ratings of self-efficacy. Paradoxically, it also increased ratings of how stressful the task was, and prolonged aversive emotional responses. These findings suggest that amphetamine differentially affects stress response components: it may increase participants' appraisals of self-efficacy without dampening the direct emotional or physiological responses to the stress. PMID:27235381

  17. Metabolomics to Detect Response of Lettuce (Lactuca sativa) to Cu(OH)2 Nanopesticides: Oxidative Stress Response and Detoxification Mechanisms.

    Zhao, Lijuan; Ortiz, Cruz; Adeleye, Adeyemi S; Hu, Qirui; Zhou, Hongjun; Huang, Yuxiong; Keller, Arturo A

    2016-09-01

    There has been an increasing influx of nanopesticides into agriculture in recent years. Understanding the interaction between nanopesticides and edible plants is crucial in evaluating the potential impact of nanotechnology on the environment and agriculture. Here we exposed lettuce plants to Cu(OH)2 nanopesticides (1050-2100 mg/L) through foliar spray for one month. Inductively coupled plasma-mass spectrometry (ICP-MS) results indicate that 97-99% (1353-2501 mg/kg) of copper was sequestered in the leaves and only a small percentage (1-3%) (17.5-56.9 mg/kg) was translocated to root tissues through phloem loading. Gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS) based metabolomics combined with partial least squares-discriminant analysis (PLS-DA) multivariate analysis revealed that Cu(OH)2 nanopesticides altered metabolite levels of lettuce leaves. Tricarboxylic (TCA) cycle and a number of amino acid-related biological pathways were disturbed. Some antioxidant levels (cis-caffeic acid, chlorogenic acid, 3,4-dihydroxycinnamic acid, dehydroascorbic acid) were significantly decreased compared to the control, indicating that oxidative stress and a defense response occurred. Nicotianamine, a copper chelator, increased by 12-27 fold compared to the control, which may represent a detoxification mechanism. The up-regulation of polyamines (spermidine and putrescine) and potassium may mitigate oxidative stress and enhance tolerance. The data presented here provide a molecular-scale perspective on the response of plants to copper nanopesticides. PMID:27483188

  18. Responses of marine plankton to pollutant stress

    Hjorth, M.

    The thesis analyses effects of pollutants on natural plankton communities on the basis of three independent mesocosm experiments and a series of laboratory experiments performed in Denmark and Greenland. The work focus on integrating functional and structural measures of community responses to...

  19. Individual differences in cortisol stress response predict increases in voice pitch during exam stress.

    Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr

    2016-09-01

    Despite a long history of empirical research, the potential vocal markers of stress remain unclear. Previous studies examining speech under stress most consistently report an increase in voice pitch (the acoustic correlate of fundamental frequency, F0), however numerous studies have failed to replicate this finding. In the present study we tested the prediction that these inconsistencies are tied to variation in the severity of the stress response, wherein voice changes may be observed predominantly among individuals who show a cortisol stress response (i.e., an increase in free cortisol levels) above a critical threshold. Voice recordings and saliva samples were collected from university psychology students at baseline and again immediately prior to an oral examination. Voice recordings included both read and spontaneous speech, from which we measured mean, minimum, maximum, and the standard deviation in F0. We observed an increase in mean and minimum F0 under stress in both read and spontaneous speech, whereas maximum F0 and its standard deviation showed no systematic changes under stress. Our results confirmed that free cortisol levels increased by an average of 74% (ranging from 0 to 270%) under stress. Critically, increases in cortisol concentrations significantly predicted increases in mean F0 under stress for both speech types, but did not predict variation in F0 at baseline. On average, stress-induced increases in voice pitch occurred only when free cortisol levels more than doubled their baseline concentrations. Our results suggest that researchers examining speech under stress should control for individual differences in the magnitude of the stress response. PMID:27188981

  20. Abscisic acid regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin.

    Rowe, James H; Topping, Jennifer F; Liu, Junli; Lindsey, Keith

    2016-07-01

    Understanding the mechanisms regulating root development under drought conditions is an important question for plant biology and world agriculture. We examine the effect of osmotic stress on abscisic acid (ABA), cytokinin and ethylene responses and how they mediate auxin transport, distribution and root growth through effects on PIN proteins. We integrate experimental data to construct hormonal crosstalk networks to formulate a systems view of root growth regulation by multiple hormones. Experimental analysis shows: that ABA-dependent and ABA-independent stress responses increase under osmotic stress, but cytokinin responses are only slightly reduced; inhibition of root growth under osmotic stress does not require ethylene signalling, but auxin can rescue root growth and meristem size; osmotic stress modulates auxin transporter levels and localization, reducing root auxin concentrations; PIN1 levels are reduced under stress in an ABA-dependent manner, overriding ethylene effects; and the interplay among ABA, ethylene, cytokinin and auxin is tissue-specific, as evidenced by differential responses of PIN1 and PIN2 to osmotic stress. Combining experimental analysis with network construction reveals that ABA regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin. PMID:26889752

  1. Transcriptomic response to stress in marine bivalves

    Q Li

    2013-10-01

    Full Text Available Marine bivalves have a set of unique capabilities to adapt to the complicated conditions owing to their habitats, living habits and feeding ways. Meanwhile, marine bivalves can be the biosensors to monitor the quality of the intertidal zones or other habitats. It is interesting for every biologist to find out the mechanisms by which organisms adapt to environmental challenges and the factors limiting their adaptive capacities. The development of biotechnology over the past few decades has provided biologists with a vast repertoire of biosensors that allow testing mRNA expression in response to environmental factors. This minireview is focused on the transcriptomic responses to abiotic and biotic stressors in bivalves and the relative methods to provide new perspectives as well as improve applications for bivalve biomonitoring studies.

  2. Physiological roles of plastid terminal oxidase in plant stress responses

    Xin Sun; Tao Wen

    2011-12-01

    The plastid terminal oxidase (PTOX) is a plastoquinol oxidase localized in the plastids of plants. It is able to transfer electrons from plastoquinone (PQ) to molecular oxygen with the formation of water. Recent studies have suggested that PTOX is beneficial for plants under environmental stresses, since it is involved in the synthesis of photoprotective carotenoids and chlororespiration, which could potentially protect the chloroplast electron transport chain (ETC) from over-reduction. The absence of PTOX in plants usually results in photo-bleached variegated leaves and impaired adaptation to environment alteration. Although PTOX level and activity has been found to increase under a wide range of stress conditions, the functions of plant PTOX in stress responses are still disputed now. In this paper, the possible physiological roles of PTOX in plant stress responses are discussed based on the recent progress.

  3. Dynamic modeling of cellular response to DNA damage based on p53 stress response networks

    Jinpeng Qi; Yongsheng Ding; Shihuang Shao

    2009-01-01

    Under acute perturbations from the outside, cells can trigger self-defensive mechanisms to fight against genome stress. To investigate the cellular response to continuous ion radiation (IR), a dynamic model for p53 stress response networks at the cellular level is proposed. The model can successfully be used to simulate the dynamic processes of double-strand breaks (DSBs) generation and their repair, switch-like ataxia telangiectasia mutated (ATM) activation, oscillations occurring in the p53-MDM2 feedback loop, as well as toxins elimination triggered by p53 stress response networks. Especially, the model can predict the plausible outcomes of cellular response under different IR dose regimes.

  4. Protein phosphorylation in response to stress in Clostridium acetobutylicum

    The possible involvement of protein phosphorylation in the clostridial stress response was investigated by radioactively labeling growing cells of Clostridium acetobutylicum with 32Pi or cell extracts with [γ-32P]ATP. Several phosphoproteins were identified; these were not affected by the growth stage of the culture. Although the extent of protein phosphorylation was increased by heat stress, the phosphoproteins did not correspond to known stress proteins seen in one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified clostridial DnaK, a stress protein, acted as a kinase catalyzing the phosphorylation of a 50-kilodalton protein. The phosphorylation of this protein was enhanced in extracts prepared from heat-stressed cells. Diadenosine-5',5 double-prime '-P1,P4-tetraphosphate had no influence on protein phosphorylation

  5. Identification of Drought-Responsive Universal Stress Proteins in Viridiplantae

    Isokpehi, Raphael D.; Simmons, Shaneka S.; Cohly, Hari H. P.; Ekunwe, Stephen I.N.; Begonia, Gregorio B.; Ayensu, Wellington K.

    2011-01-01

    Genes encoding proteins that contain the universal stress protein (USP) domain are known to provide bacteria, archaea, fungi, protozoa, and plants with the ability to respond to a plethora of environmental stresses. Specifically in plants, drought tolerance is a desirable phenotype. However, limited focused and organized functional genomic datasets exist on drought-responsive plant USP genes to facilitate their characterization. The overall objective of the investigation was to identify diver...

  6. Historical Temperature Variability Affects Coral Response to Heat Stress

    Jessica Carilli; Donner, Simon D.; Hartmann, Aaron C.

    2012-01-01

    Coral bleaching is the breakdown of symbiosis between coral animal hosts and their dinoflagellate algae symbionts in response to environmental stress. On large spatial scales, heat stress is the most common factor causing bleaching, which is predicted to increase in frequency and severity as the climate warms. There is evidence that the temperature threshold at which bleaching occurs varies with local environmental conditions and background climate conditions. We investigated the influence of...

  7. Empathy and stress related neural responses in maternal decision making

    Ho, S. Shaun; Konrath, Sara; Brown, Stephanie; Swain, James E.

    2014-01-01

    Mothers need to make caregiving decisions to meet the needs of children, which may or may not result in positive child feedback. Variations in caregivers' emotional reactivity to unpleasant child-feedback may be partially explained by their dispositional empathy levels. Furthermore, empathic response to the child's unpleasant feedback likely helps mothers to regulate their own stress. We investigated the relationship between maternal dispositional empathy, stress reactivity, and neural correl...

  8. Empathy and Stress Related Neural Responses in Maternal Decision Making

    SaraKonrath; StephanieBrown; JamesESwain

    2014-01-01

    Mothers need to make caregiving decisions to meet the needs of children, which may or may not result in positive child feedback. Variations in caregivers’ emotional reactivity to unpleasant child-feedback may be partially explained by their dispositional empathy levels. Furthermore, empathic response to the child’s unpleasant feedback likely helps mothers to regulate their own stress. We investigated the relationship between maternal dispositional empathy, stress reactivity, and neural corre...

  9. Erythropoietin Action in Stress Response, Tissue Maintenance and Metabolism

    Yuanyuan Zhang; Li Wang; Soumyadeep Dey; Mawadda Alnaeeli; Sukanya Suresh; Heather Rogers; Ruifeng Teng; Constance Tom Noguchi

    2014-01-01

    Erythropoietin (EPO) regulation of red blood cell production and its induction at reduced oxygen tension provides for the important erythropoietic response to ischemic stress. The cloning and production of recombinant human EPO has led to its clinical use in patients with anemia for two and half decades and has facilitated studies of EPO action. Reports of animal and cell models of ischemic stress in vitro and injury suggest potential EPO benefit beyond red blood cell production including vas...

  10. Forearm vascular responses to mental stress in healthy older adults

    Heffernan, Matthew J.; Patel, Hardikkumar M.; Muller, Matthew D.

    2013-01-01

    Abstract Forearm vascular conductance (FVC) increases in response to mental stress (verbal mental arithmetic) in young people. However, the effect of healthy aging and mental stress on FVC is unknown. In this study, we tested the hypothesis that FVC and cutaneous vascular conductance (CVC) would be attenuated in older adults compared to young adults. In 13 young (27 ± 1 year) and 11 older (62 ± 1 year) subjects, we quantified heart rate (HR), mean arterial pressure (MAP), FVC (Doppler ultraso...

  11. Activation of Endoplasmic Reticulum Stress Response Following Trauma-Hemorrhage

    Jian, Bixi; Hsieh, Chi-Hsun; Chen, Jianguo; Choudhry, Mashkoor; Bland, Kirby; Chaudry, Irshad; Raju, Raghavan

    2008-01-01

    Hemorrhagic trauma leads to organ dysfunction, sepsis and death. There is abnormal production of proinflammatory cytokines by Kupffer cells, tissue hypoxia and liver injury following trauma-hemorrhage. The physiological conditions consequent to trauma-hemorrhage are consistent with factors necessary to initiate endoplasmic reticulum (ER) stress and unfolded protein response. However, the contribution of ER stress to apoptosis and liver injury after trauma-hemorrhage is not known. In the prese...

  12. Stress, Roles and Responsibilities of Single Mothers in Malaysia

    Mohd Hashim Intan Hashimah; Azmawati Azman Azwan; Endut Noraida

    2015-01-01

    Life as a single mother is often associated with great demands and many challenges. This study examines how a group of single mothers in Malaysia views sources of stress and challenges in their lives. It also investigates perceived roles and responsibilities of single mothers. Three hundred single mothers from all over Malaysia were interviewed in this study. Single mothers reported relatively low level of stress that was mostly related to financial (insufficient pay) and day-to-day living. T...

  13. Stress response and mode of ventilation in preterm infants

    Quinn, M.; de Boer, R C; Ansari, N.; Baumer, J

    1998-01-01

    AIM—To assess the change in stress response in preterm babies changed from patient triggered ventilation (PTV) to conventional mandatory ventilation (CMV) and vice versa; to determine outcome in relation to stress hormone concentrations.
METHODS—A randomised controlled study was conducted in two district general hospital neonatal intensive care units. Thirty babies, treated initially with CMV, were randomly assigned to remain on CMV or to change to PTV. A second group of 29 ...

  14. Mutation as a Stress Response and the Regulation of Evolvability

    Galhardo, Rodrigo S.; Hastings, P. J.; Rosenberg, Susan M.

    2007-01-01

    Our concept of a stable genome is evolving to one in which genomes are plastic and responsive to environmental changes. Growing evidence shows that a variety of environmental stresses induce genomic instability in bacteria, yeast, and human cancer cells, generating occasional fitter mutants and potentially accelerating adaptive evolution. The emerging molecular mechanisms of stress-induced mutagenesis vary but share telling common components that underscore two common themes. The first is the...

  15. Motor/autonomic stress responses in a competitive piano performance.

    Yoshie, Michiko; Kudo, Kazutoshi; Ohtsuki, Tatsuyuki

    2009-07-01

    The present study examined the effects of psychological stress on performance quality, autonomic responses, and upper extremity muscle activity in skilled pianists through comparisons between stressful (competition) and nonstressful (rehearsal) conditions. We observed increased levels of subjective anxiety, autonomic arousal, and electromyographic activity in the competition condition, which could contribute to the impairment of performance quality. The results provide important practical implications for enhancing performance quality as well as preventing playing-related musculoskeletal disorders in musicians. PMID:19673810

  16. Exposure to stressful environments - Strategy of adaptive responses

    Farhi, Leon E.

    1991-01-01

    Stresses such as hypoxia, water lack, and heat exposure can produce strains in more than a single organ system, in turn stimulating the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups: (1) conditions that affect the supply of essential molecules, (2) stresses that prevent the body from regulating properly the output of waste products such as CO2 and heat, and (3) environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of microenvironment, is often favored by the animal.

  17. The behavioural effects of predator-induced stress responses in the cricket (Gryllus texensis): the upside of the stress response.

    Adamo, Shelley A; Kovalko, Ilya; Mosher, Brianna

    2013-12-15

    Predator-induced stress responses are thought to reduce an animal's risk of being eaten. Therefore, these stress responses should enhance anti-predator behaviour. We found that individual insects (the cricket Gryllus texensis) show reliable behavioural responses (i.e. behavioural types) in a plus-shaped maze. An individual's behaviour in the plus maze remained consistent for at least 1/2 of its adult life. However, after exposure to a model predator, both male and female crickets showed a reduced period of immobility and an increased amount of time spent under shelter compared with controls. These changes could be mimicked by injections of the insect stress neurohormone octopamine. These behavioural changes probably aid crickets in evading predators. Exposure to a model predator increased the ability of crickets to escape a live predator (a bearded dragon, Pogona vitticeps). An injection of octopamine had the same effect, showing that stress hormones can reduce predation. Using crickets to study the fitness consequences of predator-induced stress responses will help integrate ecological and biomedical concepts of 'stress'. PMID:24307711

  18. Transcriptomic responses to heat stress and bleaching in the elkhorn coral Acropora palmata

    DeSalvo, MK

    2010-03-08

    The emergence of genomic tools for reef-building corals and symbiotic anemones comes at a time when alarming losses in coral cover are being observed worldwide. These tools hold great promise in elucidating novel and unforeseen cellular processes underlying the successful mutualism between corals and their dinoflagellate endosymbionts Symbiodinium spp. Since thermal stress triggers a breakdown in the symbiosis (coral bleaching), measuring the transcriptomic response to thermal stress-induced bleaching offers an extraordinary view of cellular processes that are specific to coral–algal symbioses. In the present study, we utilized a cDNA microarray containing 2059 genes of the threatened Caribbean elkhorn coral Acropora palmata to identify genes that are differentially expressed upon thermal stress. Fragments from replicate colonies were exposed to elevated temperature for 2 d, and samples were frozen for microarray analysis after 24 and 48 h. Totals of 204 and 104 genes were differentially expressed in samples that were collected 1 and 2 d after thermal stress, respectively. Analysis of the differentially expressed genes indicates a cellular stress response in A. palmata involving (1) growth arrest, (2) chaperone activity, (3) nucleic acid stabilization and repair, and (4) removal of damaged macromolecules. Other differentially expressed processes include sensory perception, metabolite transfer between host and endosymbiont, nitric oxide signaling, and modifications to the actin cytoskeleton and extracellular matrix. The results are compared with those from a previous coral microarray study of thermal stress in Montastraea faveolata, and point to an overall evolutionary conserved bleaching response in scleractinian corals.

  19. Neonatal handling alters maternal emotional response to stress.

    Reis, Adolfo R; Jacobs, Silvana; Menegotto, Pâmela R; Silveira, Patrícia P; Lucion, Aldo B

    2016-07-01

    Neonatal handling is an experimental procedure used to analyze the effects of environmental interventions during early postpartum days (PPD). Long-lasting effects of repeated stress exposure in the neonatal period on the maternal side are poorly studied in this model. The aim of this study was to verify if handling the pups induces enduring effects on damśstress responses, increasing their risk for depression. Dams were divided into two groups (NH-Non-handled and H-Handled) based on the handling procedure (pups were handled for 1 min/per day from PPD1-PPD10) and then subdivided into four groups (NH, NH + S, H, and H + S) based on the exposure or not to restraint stress after weaning (1 hr/per day for 7 days, PPD22-PPD28). We analyzed damśbehavior in the forced swimming test (FST PPD29-PPD30), plasma basal corticosterone and BDNF levels, as well as adrenal weight (PPD31). The results show that handling alters the stress response of dams to acute and chronic stress, as evidenced by dams of the H group having increased immobility in the first day of FST (p handling may induce a long-lasting effect on maternal stress response; these changes in the damśemotional reactivity increase their susceptibility for the development of psychiatric disorders such as depression. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 614-622, 2016. PMID:27020142

  20. Stress responses in alfalfa (Medicago sativa L.)

    The isoflavonoid conjugates medicarpin-3-O-glucoside-6 double-prime-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6 double-prime-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with [14C]phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, [14C]phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of 14C-labeled, elicited cells with L-α-aminooxy-β-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures

  1. Stress responses in alfalfa (Medicago sativa L. )

    Kessmann, H.; Edwards, R.; Dixon, R.A. (Samuel Roberts Noble Foundation, Ardmore, OK (USA)); Geno, P.W. (Oklahoma State Univ., Stillwater (USA))

    1990-09-01

    The isoflavonoid conjugates medicarpin-3-O-glucoside-6{double prime}-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6{double prime}-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with ({sup 14}C)phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, ({sup 14}C)phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of {sup 14}C-labeled, elicited cells with L-{alpha}-aminooxy-{beta}-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures.

  2. Pharmacological modification of the perioperative stress response in noncardiac surgery.

    Priebe, Hans-Joachim

    2016-06-01

    The perioperative period is associated with alterations in the neuroendocrine, metabolic, and immune systems, referred to as "stress response." The resultant increased sympathetic activity and elevated serum concentrations of catecholamines may adversely affect the cardiovascular system, resulting in cardiovascular instability (hypertension, tachycardia, and arrhythmia), morbidity (myocardial ischemia, myocardial infarction, and stroke), and mortality (cardiac death and fatal stroke), particularly in patients at an elevated cardiovascular risk and with reduced cardiovascular reserve. Various strategies have been used to ameliorate the adverse perioperative cardiovascular sequelae of the perioperative stress response. Effective pharmacologic blunting of the stress response plays a crucial role in perioperative cardiac risk reduction strategies. In this context, the role of beta-adrenoceptor blockers, alpha2-adrenoceptor agonists, and statins has been extensively examined. This chapter evaluates the available evidence with respect to treatment efficacy of these commonly prescribed drugs in patients undergoing noncardiac surgery. PMID:27396805

  3. Lipid Biosynthesis Coordinates a Mitochondrial-to-Cytosolic Stress Response.

    Kim, Hyun-Eui; Grant, Ana Rodrigues; Simic, Milos S; Kohnz, Rebecca A; Nomura, Daniel K; Durieux, Jenni; Riera, Celine E; Sanchez, Melissa; Kapernick, Erik; Wolff, Suzanne; Dillin, Andrew

    2016-09-01

    Defects in mitochondrial metabolism have been increasingly linked with age-onset protein-misfolding diseases such as Alzheimer's, Parkinson's, and Huntington's. In response to protein-folding stress, compartment-specific unfolded protein responses (UPRs) within the ER, mitochondria, and cytosol work in parallel to ensure cellular protein homeostasis. While perturbation of individual compartments can make other compartments more susceptible to protein stress, the cellular conditions that trigger cross-communication between the individual UPRs remain poorly understood. We have uncovered a conserved, robust mechanism linking mitochondrial protein homeostasis and the cytosolic folding environment through changes in lipid homeostasis. Metabolic restructuring caused by mitochondrial stress or small-molecule activators trigger changes in gene expression coordinated uniquely by both the mitochondrial and cytosolic UPRs, protecting the cell from disease-associated proteins. Our data suggest an intricate and unique system of communication between UPRs in response to metabolic changes that could unveil new targets for diseases of protein misfolding. PMID:27610574

  4. Fusaric acid induces mitochondrial stress in human hepatocellular carcinoma (HepG2) cells.

    Sheik Abdul, Naeem; Nagiah, Savania; Chuturgoon, Anil A

    2016-09-01

    Fusarium spp are common contaminants of maize and produce many mycotoxins, including the fusariotoxin fusaric acid (FA). FA is a niacin related compound, chelator of divalent cations, and mediates toxicity via oxidative stress and possible mitochondrial dysregulation. Sirtuin 3 (SIRT3) is a stress response deacetylase that maintains proper mitochondrial function. We investigated the effect of FA on SIRT3 and oxidative and mitochondrial stress pathways in the hepatocellular carcinoma (HepG2) cell line. We determined FA toxicity (24 h incubation; IC50 = 104 μg/ml) on mitochondrial output, cellular and mitochondrial stress responses, mitochondrial biogenesis and markers of cell death using spectrophotometry, luminometry, qPCR and western blots. FA caused a dose dependent decrease in metabolic activity along with significant depletion of intracellular ATP. FA induced a significant increase in lipid peroxidation, despite up-regulation of the antioxidant transcription factor, Nrf2. FA significantly decreased expression of SIRT3 mRNA with a concomitant decrease in protein expression. Lon protease was also significantly down-regulated. FA induced aberrant mitochondrial biogenesis as evidenced by significantly decreased protein expressions of: PGC-1α, p-CREB, NRF1 and HSP70. Finally, FA activated apoptosis as noted by the significantly increased activity of caspases 3/7 and also induced cellular necrosis. This study provides insight into the molecular mechanisms of FA (a neglected mycotoxin) induced hepatotoxicity. PMID:27390038

  5. Stress for invasion success? Temperature stress of preceding generations modifies the response to insecticide stress in an invasive pest insect.

    Piiroinen, Saija; Lyytinen, Anne; Lindström, Leena

    2013-02-01

    Adaptation to stressful environments is one important factor influencing species invasion success. Tolerance to one stress may be complicated by exposure to other stressors experienced by the preceding generations. We studied whether parental temperature stress affects tolerance to insecticide in the invasive Colorado potato beetle Leptinotarsa decemlineata. Field-collected pyrethroid-resistant beetles were reared under either stressful (17°C) or favourable (23°C) insecticide-free environments for three generations. Then, larvae were exposed to pyrethroid insecticides in common garden conditions (23°C). Beetles were in general tolerant to stress. The parental temperature stress alone affected beetles positively (increased adult weight) but it impaired their tolerance to insecticide exposure. In contrast, offspring from the favourable temperature regime showed compensatory weight gain in response to insecticide exposure. Our study emphasizes the potential of cross-generational effects modifying species stress tolerance. When resistant pest populations invade benign environments, a re-application of insecticides may enhance their performance via hormetic effects. In turn, opposite effects may arise if parental generations have been exposed to temperature stress. Thus, the outcome of management practices of invasive pest species is difficult to predict unless we also incorporate knowledge of the evolutionary and recent (preceding generations) stress history of the given populations into pest management. PMID:23467574

  6. Proteomic analysis of the response to NaCl stress of Lactobacillus bulgaricus.

    Li, Chun; Li, Pei-Zhao; Sun, Jin-Wei; Huo, Gui-Cheng; Liu, Li-Bo

    2014-11-01

    Lactobacillus bulgaricus is commonly used in dairy products as a starter culture. Its viability during freeze-drying is of commercial interest. Here a significant (p viability improvement in L. bulgaricus, protein synthesis was analyzed by 2D difference gel electrophoresis. Nine protein spots were significantly altered by NaCl and were subsequently identified by peptide mass fingerprinting. The functions of the proteins included stress-related protein synthesis, amino acid biosynthesis, nucleotide biosynthesis, sugar metabolism, transport systems, and vitamin biosynthesis. These findings provide a considerable background regarding the NaCl stress response of L. bulgaricus. PMID:25048227

  7. Repeated neonatal handling with maternal separation permanently alters hippocampal GABAA receptors and behavioral stress responses

    Hsu, Fu-Chun; Zhang, Guo-Jun; Raol, Yogendra Sinh H.; Valentino, Rita J.; Coulter, Douglas A.; Brooks-Kayal, Amy R.

    2003-01-01

    Increasing evidence suggests that postnatal events, such as handling or maternal separation, can produce long-term changes in brain function. These are often expressed as changes in the profile of endocrine or behavioral responses to stress. Changes in γ-aminobutyric acid type A receptors (GABARs), which mediate the majority of fast synaptic inhibition in adult brain, have been proposed as one potential mediator of these behavioral effects. In the current article, we use a combination of sing...

  8. A 2-Cys peroxiredoxin in response to oxidative stress in the pine wood nematode, Bursaphelenchus xylophilus

    Zhen Li; Qingwen Zhang; Xuguo Zhou

    2016-01-01

    The pine wood nematode, Bursaphelenchus xylophilus, is the causal agent of pine wilt disease that has devastated pine forests in Asia. Parasitic nematodes are known to have evolved antioxidant stress responses that defend against host plant defenses. In this study, the infestation of whitebark pine, Pinus bungean, with B. xylophilus led to a significant increase in plant hydrogen peroxide (H2O2) and salicylic acid levels. Correspondingly, the expression of an antioxidative enzyme, 2-Cysteine ...

  9. Cellular Response to Substrate Rigidity Is Governed by Either Stress or Strain

    Yip, Ai Kia; Iwasaki, Katsuhiko; Ursekar, Chaitanya; Machiyama, Hiroaki; Saxena, Mayur; Chen, Huiling; Harada, Ichiro; Chiam, Keng-Hwee; Sawada, Yasuhiro

    2013-01-01

    Cells sense the rigidity of their substrate; however, little is known about the physical variables that determine their response to this rigidity. Here, we report traction stress measurements carried out using fibroblasts on polyacrylamide gels with Young’s moduli ranging from 6 to 110 kPa. We prepared the substrates by employing a modified method that involves N-acryloyl-6-aminocaproic acid (ACA). ACA allows for covalent binding between proteins and elastomers and thus introduces a more stab...

  10. Functional characterization of an E3 ubiquitin ligase involved in plant response to abiotic stress

    Guerra, Davide

    2010-01-01

    Protein ubiquitination is a post-translational modification that targets protein substrates for 26S proteasome-mediated degradation. It is based on the covalent attachment of the 76-amino acid eukaryotic molecule, ubiquitin, to substrate proteins. Protein ubiquitination plays a key role in a wide variety of cellular processes such as hormone signaling, DNA repair, biotic and abiotic stress response, cell cycle regulation. Ubiquitin conjugation is a multistep reaction, sequentially involvin...

  11. Molecular ecological responses of dinoflagellate, Karenia mikimotoi to environmental nitrate stress

    Highlights: ► Karenia mikimotoi which is the representative of marine dinoflagellate was studied. ► This algal proteomics was investigated integrated with ecophysiological characteristics. ► The first exploration of its proteomic responses to environmental nitrate stress. ► Some interesting homolog proteins were discovered concerning proliferation and toxin. ► The proteomic mechanisms related to nitrate stress were hypothesized. - Abstract: Karenia mikimotoi is one of the most important harmful algal species in the Chinese coastal waters, and which produce hemolytic toxins and ichthyotoxins, resulting in devastating economic losses. Previous studies demonstrated that the increase of nitrate concentration could promote the growth and reproduction of K. mikimotoi. However, the intrinsic mechanisms regarding the effects of nitrate on the K. mikimotoi photosynthesis, nucleic acid replication and differential protein expression remain to be elucidated. Our study demonstrated that nitrate stress inhibited growth of K. mikimotoi (p < 0.01). Algal chlorophyll fluorescence intensity varied slightly while algal cell cycle succession was significantly retarded by nitrate stress (p < 0.05). Sixteen proteins were detected only in nitrate-limited cultures which related to nitrate transport, signal transduction, amino acid metabolism, DNA repair and hemolysin manufacture. Eleven proteins were detected only in nitrate-replete sample and were related to photorespiration, reproduction and growth, assistance of protein modification, cytoskeleton stability and signal transduction. Based on analysis of differential proteomic functional annotations, we hypothesized a proteomic response mechanism of K. mikimotoi to environmental nitrate stress.

  12. Changes in Liver Proteome Expression of Senegalese Sole (Solea senegalensis) in Response to Repeated Handling Stress

    Cordeiro, O. D.; Silva, Tomé Santos; Alves, R. N.;

    2012-01-01

    , cathepsin B, disulfide-isomerase A3 precursor, cell-division cycle 48, and five distinct heat shock proteins), amino acid metabolism, urea cycle and methylation/folate pathways (methionine adenosyltransferase I α, phenylalanine hydroxylase, mitochondrial agmatinase, serine hydroxymethyltransferase, 3......The Senegalese sole, a high-value flatfish, is a good candidate for aquaculture production. Nevertheless, there are still issues regarding this species’ sensitivity to stress in captivity. We aimed to characterize the hepatic proteome expression for this species in response to repeated handling and...... identify potential molecular markers that indicate a physiological response to chronic stress. Two groups of fish were reared in duplicate for 28 days, one of them weekly exposed to handling stress (including hypoxia) for 3 min, and the other left undisturbed. Two-dimensional electrophoresis enabled the...

  13. Formaldehyde stress responses in bacterial pathogens

    Nathan Houqian Chen

    2016-03-01

    Full Text Available Formaldehyde is the simplest of all aldehydes and is highly cytotoxic. Its use and associated dangers from environmental exposure have been well documented. Detoxification systems for formaldehyde are found throughout the biological world and they are especially important in methylotrophic bacteria, which generate this compound as part of their metabolism of methanol. Formaldehyde metabolizing systems can be divided into those dependent upon pterin cofactors, sugar phosphates and those dependent upon glutathione. The more prevalent thiol-dependent formaldehyde detoxification system is found in many bacterial pathogens, almost all of which do not metabolize methane or methanol. This review describes the endogenous and exogenous sources of formaldehyde, its toxic effects and mechanisms of detoxification. The methods of formaldehyde sensing are also described with a focus on the formaldehyde responsive transcription factors HxlR, FrmR and NmlR. Finally, the physiological relevance of detoxification systems for formaldehyde in bacterial pathogens is discussed.

  14. Formaldehyde Stress Responses in Bacterial Pathogens.

    Chen, Nathan H; Djoko, Karrera Y; Veyrier, Frédéric J; McEwan, Alastair G

    2016-01-01

    Formaldehyde is the simplest of all aldehydes and is highly cytotoxic. Its use and associated dangers from environmental exposure have been well documented. Detoxification systems for formaldehyde are found throughout the biological world and they are especially important in methylotrophic bacteria, which generate this compound as part of their metabolism of methanol. Formaldehyde metabolizing systems can be divided into those dependent upon pterin cofactors, sugar phosphates and those dependent upon glutathione. The more prevalent thiol-dependent formaldehyde detoxification system is found in many bacterial pathogens, almost all of which do not metabolize methane or methanol. This review describes the endogenous and exogenous sources of formaldehyde, its toxic effects and mechanisms of detoxification. The methods of formaldehyde sensing are also described with a focus on the formaldehyde responsive transcription factors HxlR, FrmR, and NmlR. Finally, the physiological relevance of detoxification systems for formaldehyde in bacterial pathogens is discussed. PMID:26973631

  15. Fatty-acid metabolism is involved in stress-resistance mechanisms of Caenorhabditis elegans

    Horikawa, Makoto; Sakamoto, Kazuichi

    2009-01-01

    Fatty acids are the major components of the phospholipid bilayer and are involved in several functions of cell membrane. We previously reported that fatty-acid metabolism is involved in the regulation of DAF-2/insulin signal in Caenorhabditis elegans. In this study, we investigate the role of fatty-acid metabolism in stress resistance with respect to daf-16 in nematode. We found that fatty-acid metabolism regulates heat, osmotic, and oxidative-stress resistance in C. elegans. RNA interference...

  16. α-Linolenic acid prevents endoplasmic reticulum stress-mediated apoptosis of stearic acid lipotoxicity on primary rat hepatocytes

    Shi Hongyang

    2011-05-01

    Full Text Available Abstract Aims Lipid accumulation in non-adipose tissues leads to cell dysfunction and apoptosis, a phenomenon known as lipotoxicity. Unsaturated fatty acids may offset the lipotoxicity associated with saturated fatty acids. Stearic acid induced endoplasmic reticulum (ER stress and caused apoptotic and necrotic cell death in the primary rat hepatocytes. Methods Cell viability was investigated using MTT assay, and apoptosis was evaluated with Hoechst 33342 staining. Western blot analysis was used to examine the changes in the expression levels of glucose regulated protein 78 (GRP78, glucose regulated protein 94 (GRP94, and C/EBP homologous protein (CHOP. Caspase-3 activity was evaluated using a Caspase-3 substrate kit. Results We have studied the ability of α-linolenic acid to prevent endoplasmic reticulum stress-mediated apoptosis of rat hepatocytes elicited by stearic acid and thapsigargin. Incubation of primary rat hepatocytes for 16 h with stearic acid produced a significant increase in cell death. Stearic acid also increased levels of three indicators of ER stress -- GRP78, CHOP, and GRP94. α-Linolenic acid distinctly reduced cell death and levels of all three indicators of ER stress brought about by stearic acid. Thapsigargin, which induces ER stress produced similar effects to those obtained using stearic acid; its effects were partly reversed by α-linolenic acid. Conclusion These results suggest that α-linolenic acid prevents ER stress-mediated apoptosis of stearic acid lipotoxicity on primary rat hepatocytes might become a target to develop new antiapoptotic compounds in nonalcoholic fatty liver disease (NAFLD.

  17. Stress effects on mood, HPA axis, and autonomic response: comparison of three psychosocial stress paradigms.

    Grace E Giles

    Full Text Available Extensive experimental psychology research has attempted to parse the complex relationship between psychosocial stress, mood, cognitive performance, and physiological changes. To do so, it is necessary to have effective, validated methods to experimentally induce psychosocial stress. The Trier Social Stress Test (TSST is the most commonly used method of experimentally inducing psychosocial stress, but it is resource intensive. Less resource intense psychosocial stress tasks include the Socially Evaluative Cold Pressor Task (SECPT and a computerized mental arithmetic task (MAT. These tasks effectively produce a physiological and psychological stress response and have the benefits of requiring fewer experimenters and affording data collection from multiple participants simultaneously. The objective of this study was to compare the magnitude and duration of these three experimental psychosocial stress induction paradigms. On each of four separate days, participants completed either a control non-stressful task or one of the three experimental stressors: the TSST, SECPT, or MAT. We measured mood, working memory performance, salivary cortisol and alpha-amylase (AA, and heart rate. The TSST and SECPT exerted the most robust effects on mood and physiological measures. TSST effects were generally evident immediately post-stress as well as 10- and 20-minutes after stress cessation, whereas SECPT effects were generally limited to the duration of the stressor. The stress duration is a key determinant when planning a study that utilizes an experimental stressor, as researchers may be interested in collecting dependent measures prior to stress cessation. In this way, the TSST would allow the investigator a longer window to administer tasks of interest.

  18. Head-group acylation of monogalactosyldiacylglycerol is a common stress response, and the acyl-galactose acyl composition varies with the plant species and applied stress.

    Vu, Hieu Sy; Roth, Mary R; Tamura, Pamela; Samarakoon, Thilani; Shiva, Sunitha; Honey, Samuel; Lowe, Kaleb; Schmelz, Eric A; Williams, Todd D; Welti, Ruth

    2014-04-01

    Formation of galactose-acylated monogalactosyldiacylglycerols has been shown to be induced by leaf homogenization, mechanical wounding, avirulent bacterial infection and thawing after snap-freezing. Here, lipidomic analysis using mass spectrometry showed that galactose-acylated monogalactosyldiacylglycerols, formed in wheat (Triticum aestivum) and tomato (Solanum lycopersicum) leaves upon wounding, have acyl-galactose profiles that differ from those of wounded Arabidopsis thaliana, indicating that different plant species accumulate different acyl-galactose components in response to the same stress. Additionally, the composition of the acyl-galactose component of Arabidopsis acMGDG (galactose-acylated monogalactosyldiacylglycerol) depends on the stress treatment. After sub-lethal freezing treatment, acMGDG contained mainly non-oxidized fatty acids esterified to galactose, whereas mostly oxidized fatty acids accumulated on galactose after wounding or bacterial infection. Compositional data are consistent with acMGDG being formed in vivo by transacylation with fatty acids from digalactosyldiacylglycerols. Oxophytodienoic acid, an oxidized fatty acid, was more concentrated on the galactosyl ring of acylated monogalactosyldiacylglycerols than in galactolipids in general. Also, oxidized fatty acid-containing acylated monogalactosyldiacylglycerols increased cumulatively when wounded Arabidopsis leaves were wounded again. These findings suggest that, in Arabidopsis, the pool of galactose-acylated monogalactosyldiacylglycerols may serve to sequester oxidized fatty acids during stress responses. PMID:24286212

  19. ATF4 is involved in the regulation of simulated microgravity induced integrated stress response

    Li, Yingxian; Li, Qi; Wang, Xiaogang; Sun, Qiao; Wan, Yumin; Li, Yinghui; Bai, Yanqiang

    Objective: Many important metabolic and signaling pathways have been identified as being affected by microgravity, thereby altering cellular functions such as proliferation, differentiation, maturation and cell survival. It has been demonstrated that microgravity could induce all kinds of stress response such as endoplasmic reticulum stress and oxidative stress et al. ATF4 belongs to the ATF/CREB family of basic region leucine zipper transcription factors. ATF4 is induced by stress signals including anoxia/hypoxia, ER stress, amino acid deprivation and oxidative stress. ATF4 regulates the expression of genes involved in oxidative stress, amino acid synthesis, differentiation, metastasis and angiogenesis. The aim of this study was to examine the changes of ATF4 under microgravity, and to investigate the role of ATF4 in microgravity induced stress. MethodsMEF cells were cultured in clinostat to simulate microgravity. Reverse transcription polymerase chain reaction (RT-PCR) and western blotting were used to examine mRNA and protein levels of ATF4 expression under simulated microgravity in MEF cells. ROS levels were measured with the use of the fluorescent signal H2DCF-DA. GFP-XBP1 stably transfected cell lines was used to detect the extent of ER stress under microgravity by the intensity of GFP. Dual luciferase reporter assay was used to detect the activity of ATF4. Co-immunoprecipitation was performed to analyze protein interaction. Results: ATF4 protein levels in MEF cells increased under simulated microgravity. However, ATF4 mRNA levels were consistent. XBP1 splicing can be induced due to ER stress caused by simulated microgravity. At the same time, ROS levels were also increased. Increased ATF4 could promote the expression of CHOP, which is responsible for cell apoptosis. ATF4 also play an important role in cellular anti-oxidant stress. In ATF4 -/-MEF cells, the ROS levels after H2O2 treatment were obviously higher than that of wild type cells. HDAC4 was

  20. Inhibiting influence of testosterone on stress responsiveness during adolescence.

    Lürzel, Stephanie; Kaiser, Sylvia; Krüger, Christine; Sachser, Norbert

    2011-11-01

    The maturation of the hypothalamo-pituitary-adrenal (HPA) axis is a key-component of the changes that occur during adolescence. In guinea pigs, HPA responsiveness during late adolescence depends strongly on the quantity and quality of social interactions: Males that lived in a large mixed-sex colony over the course of adolescence exhibit a lower stress response than males that were kept in pairs (one male/one female). Since colony-housed males have higher testosterone (T) levels than pair-housed males, and inhibiting effects of T on HPA function are well known, we tested the hypothesis that the decrease in stress responsiveness found in colony-housed males is due to their high T concentrations. We manipulated T levels in two experiments: 1) gonadectomy/sham-gonadectomy of colony-housed males (which usually have high T levels), 2) application of T undecanoate/vehicle to pair-housed males (which usually have low T levels). As expected, gonadectomized males showed a significantly increased stress response in comparison with sham-gonadectomized males, and T-injected males had a significantly lower stress response than vehicle-injected males. Both experiments thus confirm an inhibiting effect of T on HPA responsiveness during adolescence, which can mediate the influence of social interactions. The reduction in stress responsiveness is hypothesized to have a biologically adaptive value: A sudden increase in glucocorticoid concentrations can enhance aggressive behavior. Thus, pair-housed males might be adapted to aggressively defend their female ('resource defense strategy'), whereas colony-housed males display little aggressive behavior and are capable of integrating themselves into a colony ('queuing strategy'). PMID:21983230

  1. β-aminobutyric acid mediated drought stress alleviation in maize (Zea mays L.).

    Shaw, Arun K; Bhardwaj, Pardeep K; Ghosh, Supriya; Roy, Sankhajit; Saha, Suman; Sherpa, Ang R; Saha, Samir K; Hossain, Zahed

    2016-02-01

    The present study highlights the role of β-aminobutyric acid (BABA) in alleviating drought stress effects in maize (Zea mays L.). Chemical priming was imposed by pretreating 1-week-old plants with 600 μM BABA prior to applying drought stress. Specific activities of key antioxidant enzymes and metabolites (ascorbate and glutathione) levels of ascorbate-glutathione cycle were studied to unravel the priming-induced modulation of plant defense system. Furthermore, changes in endogenous ABA and JA concentrations as well as mRNA expressions of key genes involved in their respective biosynthesis pathways were monitored in BABA-primed (BABA+) and non-primed (BABA-) leaves of drought-challenged plants to better understand the mechanistic insights into the BABA-induced hormonal regulation of plant response to water-deficit stress. Accelerated stomatal closure, high relative water content, and less membrane damage were observed in BABA-primed leaves under water-deficit condition. Elevated APX and SOD activity in non-primed leaves found to be insufficient to scavenge all H2O2 and O2 (·-) resulting in oxidative burst as evident after histochemical staining with NBT and DAB. A higher proline accumulation in non-primed leaves also does not give much protection against drought stress. Increased GR activity supported with the enhanced mRNA and protein expressions might help the BABA-primed plants to maintain a high GSH pool essential for sustaining balanced redox status to counter drought-induced oxidative stress damages. Hormonal analysis suggests that in maize, BABA-potentiated drought tolerance is primarily mediated through JA-dependent pathway by the activation of antioxidant defense systems while ABA biosynthesis pathway also plays an important role in fine-tuning of drought stress response. PMID:26416125

  2. Early life stress dampens stress responsiveness in adolescence: Evaluation of neuroendocrine reactivity and coping behavior.

    Hsiao, Young-Ming; Tsai, Tsung-Chih; Lin, Yu-Ting; Chen, Chien-Chung; Huang, Chiung-Chun; Hsu, Kuei-Sen

    2016-05-01

    Stressful experiences during early life (ELS) can affect brain development, thereby exerting a profound and long-lasting influence on mental development and psychological health. The stress inoculation hypothesis presupposes that individuals who have early experienced an attenuated form of stressors may gain immunity to its more virulent forms later in life. Increasing evidence demonstrates that ELS may promote the development of subsequent stress resistance, but the mechanisms underlying such adaptive changes are not fully understood. The present study evaluated the impact of fragmented dam-pup interactions by limiting the bedding and nesting material in the cage during postnatal days 2-9, a naturalistic animal model of chronic ELS, on the physiological and behavioral responses to different stressors in adolescent mice and characterized the possible underlying mechanisms. We found that ELS mice showed less social interaction deficits after chronic social defeat stress and acute restraint-tailshock stress-induced impaired long-term potentiation (LTP) and enhanced long-term depression (LTD) in hippocampal CA1 region compared with control mice. The effects of ELS on LTP and LTD were rescued by adrenalectomy. While ELS did not cause alterations in basal emotional behaviors, it significantly enhanced stress coping behaviors in both the tail suspension and the forced swimming tests. ELS mice exhibited a significant decrease in corticosterone response and trafficking of glucocorticoid receptors to the nucleus in response to acute restraint stress. Altogether, our data support the hypothesis that stress inoculation training, via early exposure to manageable stress, may enhance resistance to other unrelated extreme stressors in adolescence. PMID:26881834

  3. Response of Saccharomyces cerevisiae to cadmium stress

    Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia], e-mail: luamatu@uol.com.br; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Lab. de Ativacao Neutronica], e-mail: menezes@cdtn.br; Rosa, Carlos Augusto [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Microbiologia], e-mail: carlrosa@icb.ufmg

    2009-07-01

    The intensification of industrial activity has been greatly contributing with the increase of heavy metals in the environment. Among these heavy metals, cadmium becomes a serious pervasive environmental pollutant. The cadmium is a heavy metal with no biological function, very toxic and carcinogenic at low concentrations. The toxicity of cadmium and several other metals can be mainly attributed to the multiplicity of coordination complexes and clusters that they can form. Some aspects of the cellular response to cadmium were extensively investigated in the yeast Saccharomyces cerevisiae. The primary site of interaction between many toxic metals and microbial cells is the plasma membrane. Plasma-membrane permeabilisation has been reported in a variety of microorganisms following cadmium exposure, and is considered one mechanism of cadmium toxicity in the yeast. In this work, using the yeast strain S. cerevisiae W303-WT, we have investigated the relationships between Cd uptake and release of cellular metal ions (K{sup +} and Na{sup +}) using neutron activation technique. The neutron activation was an easy, rapid and suitable technique for doing these metal determinations on yeast cells; was observed the change in morphology of the strains during the process of Cd accumulation, these alterations were observed by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) during incorporation of cadmium. (author)

  4. Reactive oxygen species in response of plants to gravity stress

    Jadko, Sergiy

    2016-07-01

    Reactive oxygen species (ROS) as second messengers can induce stress response of plants. Thioredoxins (Trx) and peroxiredoxins (Prx) can function as sensors and transmitters of the ROS in stress signaling and antioxidant response. 12-14 days old tissue culture of Arabidopsis thaliana have been investigated. Hypergravity stress was induced by centrifugation at 10 and 20 g during 30 and 90 min and than intensity of spontaneous chemiluminescence (SChL/ROS content), Trx and Prx activities were determined. All experiments were repeated from 3 to 5 times and the obtained data were statistically treated. In the tissue culture under development of the stress there were an increase in intensity of SChL and Trx and Prx activities. Thus, under hypergravity stress in the plant occurred early increase in the ROS level and the ROS induced the increase in the Trx and Prx activities. Prx and Trx can also participate in the formation of stress respons as acceptors and transducers of the redox signals. Increase in the activity of these enzymes primarily aimed at increasing of the total antioxidant activity in the cells to prevent of the plant to development of oxidative degradation by ROS.

  5. Understanding Abiotic Stress Tolerance Mechanisms: Recent Studies on Stress Response in Rice

    Ji-Ping Gao; Dai-Yin Chao; Hong-Xuan Lin

    2007-01-01

    Abiotic stress is the main factor negatively affecting crop growth and productivity worldwide. The advances in physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to stresses. Rice plants are sensitive to various abiotic stresses. In this short review, we present recent progresses in adaptation of rice to salinity, water deficit and submergence. Many studies show that salt tolerance is tightly associated with the ability to maintain ion homeostasis under salinity. Na+ transporter SKC1 unloads NaMrom xylem, plasma membrane NaVHTantiporter SOS1 excludes sodium out of cytosol and tonoplast Na+/H+antiporter NHX1 sequesters Na+ into the vacuole. Silicon deposition in exodermis and endodermis of rice root reduces sodium transport through the apoplastic pathway. A number of transcription factors regulate stress-inducible gene expression that leads to initiating stress responses and establishing plant stress tolerance. Overexpression of some transcription factors, including DREB/CBF and MAC, enhances salt, drought, and cold tolerance in rice. A variant of one of ERF family genes, Sub1A-1, confers immersion tolerance to lowland rice. These findings and their exploitation will hold promise for engineering breeding to protect crop plants from certain abiotic stresses.

  6. Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

    Christen, Verena [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Capelle, Martinus [Crucell, P.O. Box 2048, NL-2301 Leiden (Netherlands); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology Zürich, Department of Environmental Systems Science, CH-8092 Zürich (Switzerland)

    2013-10-15

    Silver nanoparticles (AgNPs) find increasing applications, and therefore humans and the environment are increasingly exposed to them. However, potential toxicological implications are not sufficiently known. Here we investigate effects of AgNPs (average size 120 nm) on zebrafish in vitro and in vivo, and compare them to human hepatoma cells (Huh7). AgNPs are incorporated in zebrafish liver cells (ZFL) and Huh7, and in zebrafish embryos. In ZFL cells AgNPs lead to induction of reactive oxygen species (ROS), endoplasmatic reticulum (ER) stress response, and TNF-α. Transcriptional alterations also occur in pro-apoptotic genes p53 and Bax. The transcriptional profile differed in ZFL and Huh7 cells. In ZFL cells, the ER stress marker BiP is induced, concomitant with the ER stress marker ATF-6 and spliced XBP-1 after 6 h and 24 h exposure to 0.5 g/L and 0.05 g/L AgNPs, respectively. This indicates the induction of different pathways of the ER stress response. Moreover, AgNPs induce TNF-α. In zebrafish embryos exposed to 0.01, 0.1, 1 and 5 mg/L AgNPs hatching was affected and morphological defects occurred at high concentrations. ER stress related gene transcripts BiP and Synv are significantly up-regulated after 24 h at 0.1 and 5 mg/L AgNPs. Furthermore, transcriptional alterations occurred in the pro-apoptotic genes Noxa and p21. The ER stress response was strong in ZFL cells and occurred in zebrafish embryos as well. Our data demonstrate for the first time that AgNPs lead to induction of ER stress in zebrafish. The induction of ER stress can have several consequences including the activation of apoptotic and inflammatory pathways. - Highlights: • Effects of silver nanoparticles (120 nm AgNPs) are investigated in zebrafish. • AgNPs induce all ER stress reponses in vitro in zebrafish liver cells. • AgNPs induce weak ER stress in zebrafish embryos. • AgNPs induce oxidative stress and transcripts of pro-apoptosis genes.

  7. Erythropoietin Action in Stress Response, Tissue Maintenance and Metabolism

    Yuanyuan Zhang

    2014-06-01

    Full Text Available Erythropoietin (EPO regulation of red blood cell production and its induction at reduced oxygen tension provides for the important erythropoietic response to ischemic stress. The cloning and production of recombinant human EPO has led to its clinical use in patients with anemia for two and half decades and has facilitated studies of EPO action. Reports of animal and cell models of ischemic stress in vitro and injury suggest potential EPO benefit beyond red blood cell production including vascular endothelial response to increase nitric oxide production, which facilitates oxygen delivery to brain, heart and other non-hematopoietic tissues. This review discusses these and other reports of EPO action beyond red blood cell production, including EPO response affecting metabolism and obesity in animal models. Observations of EPO activity in cell and animal model systems, including mice with tissue specific deletion of EPO receptor (EpoR, suggest the potential for EPO response in metabolism and disease.

  8. Genome-wide identification, expression analysis of auxin-responsive GH3 family genes in maize (Zea mays L.) under abiotic stresses

    Shangguo Feng; Runqing Yue; Sun Tao Yanjun Yang; Lei Zhang; Mingfeng Xu; Huizhong Wang; Chenjia Shen

    2015-01-01

    Auxin is involved in different aspects of plant growth and development by regulating the expression of auxin-responsive family genes. As one of the three major auxin-responsive families, GH3 (Gretchen Hagen3) genes participate in auxin homeostasis by catalyzing auxin conjugation and bounding free indole-3-acetic acid (IAA) to amino acids. However, how GH3 genes function in responses to abiotic stresses and various hormones in maize is largely unknown. Here, the latest updated maize (Zea mays L.) reference genome sequence was used to characterize and analyze the ZmGH3 family genes from maize. The results showed that 13 ZmGH3 genes were mapped on five maize chromosomes (total 10 chromosomes). Highly diversified gene structures and tissue-specific expression patterns suggested the possibility of function diversification for these genes in response to environmental stresses and hormone stimuli. The expression patterns of ZmGH3 genes are responsive to several abiotic stresses (salt, drought and cadmium) and major stress-related hormones (abscisic acid, salicylic acid and jasmonic acid). Various environmental factors suppress auxin free IAA contents in maize roots suggesting that these abiotic stresses and hormones might alter GH3-mediated auxin levels. The respon-siveness of ZmGH3 genes to a wide range of abiotic stresses and stress-related hormones suggested that ZmGH3s are involved in maize tolerance to environmental stresses.

  9. REM SLEEP REBOUND AS AN ADAPTIVE RESPONSE TO STRESSFUL SITUATIONS

    Deborah eSuchecki

    2012-04-01

    Full Text Available Stress and sleep are related to each other in a bidirectional way. If on one hand poor or inadequate sleep exacerbates emotional, behavioral and stress-related responses, on the other hand acute stress induces sleep rebound, most likely as a form to cope with the adverse stimuli. Chronic stress, conversely, has been claimed to be one of the triggering factors of emotional-related sleep disorders, such as insomnia, depressive- and anxiety-disorders. These outcomes are dependent on individual psychobiological characteristics, which confer more complexity to the stress-sleep relationship. Its neurobiology has only recently begun to be explored, through animal models, which are also valuable for the development of potential therapeutic agents and preventive actions. This review seeks to present data on the effects of stress on sleep and the different approaches used to study this relationship as well as possible neurobiological underpinnings and mechanisms involved. The results of numerous studies in humans and animals indicate that increased sleep, especially the REM phase, following a stressful situation is an important adaptive behavior for recovery. However, this endogenous advantage appears to be impaired in human beings and rodent strains that exhibit high levels of anxiety and anxiety-like behavior.

  10. Response and energy dissipation of rock under stochastic stress waves

    DENG Jian; BIAN Li

    2007-01-01

    The response and energy dissipation of rock under stochastic stress waves were analyzed based on dynamic fracture criterion of brittle materials integrating with Fourier transform methods of spectral analysis When the stochastic stress waves transnut through rocks,the frequency and energy ratio of harmonic components were calculated by analytical and discrete analysis methods.The stress waves in shale, malmstone and liparite were taken as examples to illustrate the proposed analysis methods.The results show the harder the rock, the less absorption of energy,the more the useless elastic waves transmitting through rock, and the narrower the cutoff frequency to fracture rock.When the whole stress energy doubles either by doubling the duration time or byincreasing the amplitude of stress wave, ratio of the energy of elastic waves transmitting through rock to me whole stress energy (i.e.energy dissipation ratio)is decreased to 10%-15%. When doubling the duration time.the cutoff frequency to fracture rock remains constant.However, with the increase of the amplitude of stress wave. the cutoff frequency increases accordingly.

  11. Global metabolomic responses of Nitrosomonas europaea 19718 to cold stress and altered ammonia feeding patterns

    Lu, Huijie

    2015-11-05

    © 2015 Springer-Verlag Berlin Heidelberg The model ammonia-oxidizing bacterium Nitrosomonas europaea represents one of the environmentally and biotechnologically significant microorganisms. Genome-based studies over the last decade have led to many intriguing discoveries about its cellular biochemistry and physiology. However, knowledge regarding the regulation of overall metabolic routes in response to various environmental stresses is limited due to a lack of comprehensive, time-resolved metabolomic analyses. In this study, gas chromatography–mass spectrometry (GC-MS)-based metabolic profiling was performed to characterize the temporal variations of N. europaea 19718 intercellular metabolites in response to varied temperature (23 and 10 °C) and ammonia feeding patterns (shock loading and continuous feeding of 20 mg N/L). Approximately 87 metabolites were successfully identified and mapped to the existing pathways of N. europaea 19718, allowing interpretation of the influence of temperature and feeding pattern on metabolite levels. In general, varied temperature had a more profound influence on the overall metabolism than varied feeding patterns. Total extracellular metabolite concentrations (relative to internal standards and normalized to biomass weight) were lower under cold stress and shock loading conditions compared with the control (continuous feeding at 23 °C). Cold stress caused the widespread downregulation of metabolites involved in central carbon metabolism, amino acid, and lipid synthesis (e.g., malonic acid, succinic acid, putrescine, and phosphonolpyruvate). Metabolites that showed differences under varied feeding patterns were mainly involved in nucleotide acid, amino acid, and lipid metabolism (e.g., adenine, uracil, and spermidine). This study highlighted the roles of central carbon and nitrogen metabolism in countering cold stress and altered ammonia availability. In addition, transcriptomic, proteomic, and metabolomic data from three

  12. Morphological and Physiological Responses of Strawberry Plants to Water Stress

    Krzysztof Klamkowski; Waldemar Treder

    2006-01-01

    The most of previous studies have been focused on the effect of water stress on plant yielding. However, the conditions in which plants grow from the moment of planting might affect their morphology and physiological response. The aim of this study was to examine the effect of water deficiency on growth and plant physiological response of strawberry (Fragaria x ananassa Duch. cv. ‘Salut’) under greenhouse conditions. The plants were grown in plastic containers filled with peat substratum. Wat...

  13. ADRENERGIC RESPONSES TO STRESS: TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL CHANGES

    Wong, Dona L.; Tai, T. C.; Wong-Faull, David C.; Claycomb, Robert; Kvetnansky, Richard

    2008-01-01

    Stress effects on adrenergic responses in rats were examined in adrenal medulla, the primary source of circulating epinephrine (Epi). Irrespective of duration, immobilization (IMMO) increased adrenal corticosterone to the same extent. In contrast, epinephrine changed little, suggesting that Epi synthesis replenishes adrenal pools and sustains circulating levels for the heightened alertness and physiological changes required of the "flight or fight" response. IMMO also induced the epinephrine-...

  14. Isolation and expression studies of the ERD15 gene involved in drought-stressed responses.

    Shao, H H; Chen, S D; Zhang, K; Cao, Q H; Zhou, H; Ma, Q Q; He, B; Yuan, X H; Wang, Y; Chen, Y H; Yong, B

    2014-01-01

    The early response to the dehydration 15 (ERD15) gene is widely involved in the processes of signal transduction, programmed cell death, gene transcription, and stress tolerance in plants. In a previous study, the ERD15 gene was shown to be an important regulator of the abscisic acid response and salicylic acid-dependent defense pathway, acting as an important negative regulator of abscisic acid. The complete IbERD15 gene (accession No. KF723428) was isolated by reverse transcription-polymerase chain reaction. The IbERD15 gene contains an open reading frame of 504 bp, encodes a peptide of 167 amino acids, and has a molecular mass of 18.725 kDa. The transcript levels of the IbERD15 gene in a variety of tissues were examined by digital gene expression profiling. The roots of the sweet potato were treated by 3 degrees of polyethylene glycol, and the results indicate that the IbERD15 gene might play an important role in the defense response to drought stress. Moreover, the IbERD15 gene was successfully transformed into yeast cells for analysis of drought tolerance in transgenic yeast. PMID:25526205

  15. Enterovirus Control of Translation and RNA Granule Stress Responses.

    Lloyd, Richard E

    2016-01-01

    Enteroviruses such as poliovirus (PV) and coxsackievirus B3 (CVB3) have evolved several parallel strategies to regulate cellular gene expression and stress responses to ensure efficient expression of the viral genome. Enteroviruses utilize their encoded proteinases to take over the cellular translation apparatus and direct ribosomes to viral mRNAs. In addition, viral proteinases are used to control and repress the two main types of cytoplasmic RNA granules, stress granules (SGs) and processing bodies (P-bodies, PBs), which are stress-responsive dynamic structures involved in repression of gene expression. This review discusses these processes and the current understanding of the underlying mechanisms with respect to enterovirus infections. In addition, the review discusses accumulating data suggesting linkage exists between RNA granule formation and innate immune sensing and activation. PMID:27043612

  16. Stress and fear responses in the teleost pallium

    Silva, Patricia Isabel da Mota E.; Martins, C.I.M.; Khan, Uniza Wahid;

    2015-01-01

    been found in the teleost telencephalon. The dorsolateral (Dl) and dorsomedial (Dm) regions of the pallium are thought to perform hippocampus and amygdala-like functions respectively. To what degree these regions are involved in the neuroendocrine responses to stress and predator cues however remains...... largely unknown. In the present study the involvement of Dl and Dm in such responses was investigated by exposing Nile tilapia (Oreochromis niloticus) to a standardized confinement stress and to skin extract from conspecifics. Nile tilapia develops a characteristic anticipatory behaviour to hand feeding...... studies combining skin extract with other challenges are needed to reveal neuroendocrine effects associated with this predator cue. Confinement stress resulted in an elevation of cortisol and serotonin (5-hydroxytryptamine, 5-HT) metabolism in both Dl and Dm. A similar tendency was observed in fish...

  17. Exposure to Stressful Environments: Strategy of Adaptive Responses

    Farhi, Leon E.

    1991-01-01

    Any new natural environment may generate a number of stresses (such as hypoxia, water lack, and heat exposure), each of which can produce strains in more than a single organ system. Every strain may in turn stimulate the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups. The first category includes conditions that affect the supply of essential molecules, while the second is made up by those stresses that prevent the body from regulating properly the output of waste products, such as CO2 and heat. In both classes, there is a small number of responses, similar in principle, regardless of the specific situation. The third unit is created by environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of micro-environment, is often favored by the animal.

  18. Saturated fatty acids trigger TLR4-mediated inflammatory response.

    Rocha, D M; Caldas, A P; Oliveira, L L; Bressan, J; Hermsdorff, H H

    2016-01-01

    Toll-like receptors (TLR) mediate infection-induced inflammation and sterile inflammation by endogenous molecules. Among the TLR family, TLR4 is the best understood. However, while its downstream signaling pathways have been well defined, not all ligands of TLR4 are currently known. Current evidence suggests that saturated fatty acids (SFA) act as non-microbial TLR4 agonists, and trigger its inflammatory response. Thus, our present review provides a new perspective on the potential mechanism by which SFAs could modulate TLR4-induced inflammatory responses: (1) SFAs can be recognized by CD14-TLR4-MD2 complex and trigger inflammatory pathways, similar to lipopolysaccharide (LPS). (2) SFAs lead to modification of gut microbiota with an overproduction of LPS after a high-fat intake, enhancing this natural TLR4 ligand. (3) In addition, this metabolic endotoxemia leads to an oxidative stress thereby producing atherogenic lipids - oxLDL and oxidized phospholipids - which trigger CD36-TLR4-TLR6 inflammatory response. (4) Also, the high SFA consumption increases the lipemia and the mmLDL and oxLDL formation through oxidative modifications of LDL. The mmLDL, unlike oxLDL, is involved in activation of the CD14-TLR4-MD2 inflammatory pathway. Those molecules can induce TLR4 inflammatory response by MyD88-dependent and/or MyD88-independent pathways that, in turn, promotes the expression of proinflammatory transcript factors such as factor nuclear kappa B (NF-κB), which plays a crucial role in the induction of inflammatory mediators (cytokines, chemokines, or costimulatory molecules) implicated in the development and progression of many chronic diseases. PMID:26687466

  19. Mass spectrometry-based plant metabolomics: Metabolite responses to abiotic stress.

    Jorge, Tiago F; Rodrigues, João A; Caldana, Camila; Schmidt, Romy; van Dongen, Joost T; Thomas-Oates, Jane; António, Carla

    2016-09-01

    Metabolomics is one omics approach that can be used to acquire comprehensive information on the composition of a metabolite pool to provide a functional screen of the cellular state. Studies of the plant metabolome include analysis of a wide range of chemical species with diverse physical properties, from ionic inorganic compounds to biochemically derived hydrophilic carbohydrates, organic and amino acids, and a range of hydrophobic lipid-related compounds. This complexitiy brings huge challenges to the analytical technologies employed in current plant metabolomics programs, and powerful analytical tools are required for the separation and characterization of this extremely high compound diversity present in biological sample matrices. The use of mass spectrometry (MS)-based analytical platforms to profile stress-responsive metabolites that allow some plants to adapt to adverse environmental conditions is fundamental in current plant biotechnology research programs for the understanding and development of stress-tolerant plants. In this review, we describe recent applications of metabolomics and emphasize its increasing application to study plant responses to environmental (stress-) factors, including drought, salt, low oxygen caused by waterlogging or flooding of the soil, temperature, light and oxidative stress (or a combination of them). Advances in understanding the global changes occurring in plant metabolism under specific abiotic stress conditions are fundamental to enhance plant fitness and increase stress tolerance. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 35:620-649, 2016. PMID:25589422

  20. Rapid enzymatic response to UV stress in zooplankton

    Souza, M.S.; Hansson, L.-A.; Hylander, Samuel; Modenutti, B.; Balseiro, E.

    2012-01-01

    (glutathione S-transferase, GST), that regulate apoptosis cell death (Caspase-3, Casp-3), and that facilitate neurotransmissions (cholinesterase-ChE). None of these enzyme systems is alone sufficient, but they act in concert to reduce the stress level of the organism. The interplay among enzymatic responses...

  1. Oxidative stress response pathways: Fission yeast as archetype

    Papadakis, Manos A.; Workman, Christopher

    2015-01-01

    Schizosaccharomyces pombe is a popular model eukaryotic organism to study diverse aspects of mammalian biology, including responses to cellular stress triggered by redox imbalances within its compartments. The review considers the current knowledge on the signaling pathways that govern the transc...

  2. Cellular stress responses for monitoring and modulating ageing

    Demirovic, Dino; Schnebert, Sylvianne; Nizard, Carine;

    2013-01-01

    protectors and stimulators of homeodynamics, and create a kind of “gold-standard” for monitoring the efficacy of other potential antiageing and pro-survival natural and synthetic compounds. We have so far standardised an effective method for detecting all seven stress response pathways, by several...

  3. Physiological Response to Drought Stress at Different Stages in Peanut

    Drought is a major factor in reducing productivity in peanut (Arachis hypogaea L.). The objectives of this study were to: 1) investigate the response patterns of relative water content (RWC), specific leaf area (SLA), and leaf dry mater content (LDMC) to drought stress at three stages of 30 60, and ...

  4. Adaptive Patterns of Stress Responsivity: A Preliminary Investigation

    Del Giudice, Marco; Hinnant, J. Benjamin; Ellis, Bruce J.; El-Sheikh, Mona

    2012-01-01

    The adaptive calibration model (ACM) is an evolutionary-developmental theory of individual differences in stress responsivity. In this article, we tested some key predictions of the ACM in a middle childhood sample (N = 256). Measures of autonomic nervous system activity across the sympathetic and parasympathetic branches validated the 4-pattern…

  5. Effect of Dietary Conjugated Linoleic Acid Supplementation on Early Inflammatory Responses during Cutaneous Wound Healing

    Na-Young Park

    2010-01-01

    Full Text Available Inflammatory response is considered the most important period that regulates the entire healing process. Conjugated linoleic acid (CLA, a class of linoleic acid positional and geometric isomers, is well known for its antioxidant and anti-inflammatory properties. We hypothesized that dietary CLA supplementation accelerates cutaneous wound healing by regulating antioxidant and anti-inflammatory functions. To investigate wound closure rates and inflammatory responses, we used a full-thickness excisional wound model after 2-week treatments with control, 0.5%, or 1% CLA-supplemented diet. Mice fed dietary CLA supplementation had reduced levels of oxidative stress and inflammatory markers. Moreover, the wound closure rate was improved significantly in mice fed a 1% CLA-supplemented diet during early stage of wound healing (inflammatory stage. We conclude that dietary CLA supplementation enhances the early stage of cutaneous wound healing as a result of modulating oxidative stress and inflammatory responses.

  6. Secondary stress responses of zebrafish to different pH: Evaluation in a seasonal manner

    Md. Mahiuddin Zahangir

    2015-11-01

    Full Text Available Stress is one of the most critical factors in fish health. The response to stress in fish is characterized by the stimulation of the hypothalamus, which results in the activation of the neuroendocrine system and a subsequent cascade of metabolic and physiological changes. The present paper deals with the stress responses of water pH on certain biochemical indices and hematological parameters of zebrafish in a seasonal basis. Zebrafish were exposed to different pH e.g., 7.2, 5.0 and 10.0 and the secondary stress responses were observed. The result showed that exposure to pH 5.0 and 10.0 on zebrafish exerted stresses with reference to seasons. Higher values of blood glucose content observed in the month of summer than the month of winter and females showed higher values than males. Chronic effects of pH on the hematological parameters were also significant between these seasons. In conclusion, exposure to pH at sub-lethal concentrations induced biochemical and hematological alterations in zebrafish and offers a simple tool to evaluate the potential risk of polluted water (acid and base to fish.

  7. Influence of temperature on acid-stress adaptation in Listeria monocytogenes

    Several factors play critical roles in controlling the induction of acid-stress adaptation in L. monocytogenes. Our findings show that temperature plays a significant role in the induction of acid-stress adaptation in Listeria monocytogenes and two distinct patterns were observed: (I) Presence of su...

  8. Transactional Associations between Youths' Responses to Peer Stress and Depression: The Moderating Roles of Sex and Stress Exposure

    Agoston, Anna M.; Rudolph, Karen D.

    2011-01-01

    This study examined transactional associations between responses to peer stress and depression in youth. Specifically, it tested the hypotheses that (a) depression would predict fewer effortful responses and more involuntary, dysregulated responses to peer stress over time; and (b) fewer adaptive and more maladaptive responses would predict…

  9. Adipose Fatty Acid Oxidation Is Required for Thermogenesis and Potentiates Oxidative Stress-Induced Inflammation

    Jieun Lee

    2015-01-01

    Full Text Available To understand the contribution of adipose tissue fatty acid oxidation to whole-body metabolism, we generated mice with an adipose-specific knockout of carnitine palmitoyltransferase 2 (CPT2A−/−, an obligate step in mitochondrial long-chain fatty acid oxidation. CPT2A−/− mice became hypothermic after an acute cold challenge, and CPT2A−/− brown adipose tissue (BAT failed to upregulate thermogenic genes in response to agonist-induced stimulation. The adipose-specific loss of CPT2 resulted in diet-dependent changes in adiposity but did not result in changes in body weight on low- or high-fat diets. Additionally, CPT2A−/− mice had suppressed high-fat diet-induced oxidative stress and inflammation in visceral white adipose tissue (WAT; however, high-fat diet-induced glucose intolerance was not improved. These data show that fatty acid oxidation is required for cold-induced thermogenesis in BAT and high-fat diet-induced oxidative stress and inflammation in WAT.

  10. Hyaluronic Acid Inhibits Polycation Induced Cellular Responses

    lalenti, A.; Lanaro, A.; Brignola, G.; Marotta, P; Di Rosa, M.

    1994-01-01

    Positively charged macromolecules cause a variety of pathological events through their electrostatic interaction with anionic sites present on the membrane of target cells. In the present study we have investigated the effect of hyaluronic acid, a negatively charged molecule, on rat paw oedema induced by poly-L-lysine as well as on histamine release from rat mast cells and nitric oxide formation from rabbit aorta, both induced by this polycation. The results indicate that hyaluronic acid is a...

  11. Associations Between Paternal Responsiveness and Stress Responsiveness in the Biparental California Mouse, Peromyscus californicus

    Chauke, Miyetani

    2012-01-01

    The mechanistic basis of paternal behavior in mammals is poorly understood. Assuming there are parallels between the factors mediating maternal and paternal behavior, it can be expected that the onset of paternal behavior is facilitated by reductions in stress responsiveness, as occurs in females of several mammalian species. This dissertation describes studies investigating the role of stress responsiveness in the expression of paternal behavior in biparental, monogamous California mice (Per...

  12. Calcium affecting protein expression in longan under simulated acid rain stress.

    Pan, Tengfei; Li, Yongyu; Ma, Cuilan; Qiu, Dongliang

    2015-08-01

    Longan (Dimocarpus longana Lour. cv. Wulongling) of uniform one-aged seedlings grown in pots were selected to study specific proteins expressed in leaves under simulated acid rain (SiAR) stress and exogenous Ca(2+) regulation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results showed that there was a protein band specifically expressed under SiAR of pH 2.5 stress for 15 days with its molecular weight of about 23 kD. A 17 kD protein band specifically expressed after SiAR stress 5 days. Compared with pH 2.5, the pH 3.5 of SiAR made a less influence to protein expression. Two-dimensional electrophoresis (2-DE) results showed that six new specific proteins including C4 (20.2 kD pI 6.0), F (24 kD pI 6.35), B3 (22.3 kD pI 6.35), B4 (23.5 kD pI 6.5), C5 (21.8 kD pI 5.6), and C6 (20.2 kD pI 5.6) specifically expressed. C4 always expressed during SiAR stress. F expressed under the stress of pH 2.5 for 15 days and expressed in all pH SiAR stress for 20 days. The expression of proteins including B3, C5, and C6 was related to pH value and stress intensity of SiAR. The expression of B4 resulted from synergistic effects of SiAR and Ca. The expression of G1 (Mr 19.3 kD, pI 4.5), G2 (Mr 17.8 kD, pI 4.65), G3 (Mr 16.6 kD, pI 4.6), and G4 (Mr 14.7 kD, pI 4.4) enhanced under the treatment of 5 mM ethylene glycol tetraacetic acid (EGTA) and 2 mM chlorpromazine (CPZ). These proteins showed antagonistic effects and might be relative to the Ca-calmodulin (Ca-CaM) system of longan in response to SiAR stress. PMID:25893616

  13. EFFECT OF SALICYLIC ACID AND ASCORBIC ACID ON GERMINATION INDEXES AND ENZYME ACTIVITY OF SORGHUM SEEDS UNDER DROUGHT STRESS

    Tabatabaei S. A.

    2013-01-01

    Seed priming methods have been used to increase germination characteristics under stress conditions. The effects of drought stress (0, -4, -8, -12 and -16 bar) and salicylic acid 25 ppm at 15 °C for 15 h and ascorbic acid 25 ppm at 15 °C for 15 h on germination percentage, germination index, means time to germination, normal seedling percentage and enzyme activity were assessed in the laboratory for sorghum seeds (Sorghum bicolor L.). Results showed that the ...

  14. TRANSCRIPTOMIC CHANGES DRIVE PHYSIOLOGICAL RESPONSES TO PROGRESSIVE DROUGHT STRESS AND REHYDRATION IN TOMATO

    Paolo eIovieno

    2016-03-01

    Full Text Available Tomato is a major crop in the Mediterranean basin, where the cultivation in the open field is often vulnerable to drought. In order to adapt and survive to naturally occurring cycles of drought stress and recovery, plants employ a coordinated array of physiological, biochemical and molecular responses. Transcriptomic studies on tomato responses to drought and subsequent recovery are few in number. As the search for novel traits to improve the genetic tolerance to drought increases, a better understanding of these responses is required. To address this need we designed a study in which we induced two cycles of prolonged drought stress and a single recovery by rewatering in tomato. In order to dissect the complexity of plant responses to drought, we analyzed the physiological responses (stomatal conductance, CO2 assimilation and chlorophyll fluorescence, abscisic acid (ABA and proline contents. In addition to the physiological and metabolite assays, we generated transcriptomes for multiple points during the stress and recovery cycles. Cluster analysis of differentially expressed genes between the conditions has revealed potential novel components in stress response. The observed reduction in leaf gas exchanges and efficiency of the photosystem PSII was concomitant with a general down-regulation of genes belonging to the photosynthesis, light harvesting and photosystem I and II category induced by drought stress. Gene ontology (GO categories such as cell proliferation and cell cycle were also significantly enriched in the down-regulated fraction of genes upon drought stress, which may contribute to explain the observed growth reduction. Several histone variants were also repressed during drought stress, indicating that chromatin associated processes are also affected by drought. As expected, ABA accumulated after prolonged water deficit, driving the observed enrichment of stress related GOs in the up-regulated gene fractions, which included

  15. Gene Networks in Plant Ozone Stress Response and Tolerance

    Agnieszka Ludwikow; Jan Sadowski

    2008-01-01

    For many plant species ozone stress has become much more severe in the last decade. The accumulating evidence for the significant effects of ozone pollutant on crop and forest yield situate ozone as one of the most important environmental stress factors that limits plant productivity woddwide. Today, transcdptomic approaches seem to give the best coverage of genome level responses. Therefore, microarray serves as an invaluable tool for global gene expression analyses, unravelling new information about gene pathways, in-species and crose-species gene expression comparison, and for the characterization of unknown relationships between genes. In this review we summadze the recent progress in the transcdptomics of ozone to demonstrate the benefits that can be harvested from the application of integrative and systematic analytical approaches to study ozone stress response. We focused our consideration on microarray analyses identifying gene networks responsible for response and tolerance to elevated ozone concentration. From these analyses it is now possible to notice how plant ozone defense responses depend on the interplay between many complex signaling pathways and metabolite signals.

  16. Release of brain amino acids during hyposmolar stress and energy deprivation.

    Haugstad, T S; Langmoen, I A

    1996-04-01

    The release of 10 amino acids from rat hippocampal slices during exposure to hyposmotic stress or energy deprivation was measured by high-performance liquid chromatography. Exposing the slices to hyposmotic stress by lowering extracellular NaCl caused a 10-fold release of taurine (p alanine release (p isoelectric point) and hydropathy indexes. Energy deprivation increased the permissivity in the following order: acidic > neutral > basic. Among neutral amino acids, permissivity increased with increasing hydrophobicity. These results indicate that the mechanisms of amino acid release are different during cerebral ischemia and hyposmotic stress. PMID:8829565

  17. Transgenerational stress memory is not a general response in Arabidopsis.

    Ales Pecinka

    Full Text Available Adverse conditions can trigger DNA damage as well as DNA repair responses in plants. A variety of stress factors are known to stimulate homologous recombination, the most accurate repair pathway, by increasing the concentration of necessary enzymatic components and the frequency of events. This effect has been reported to last into subsequent generations not exposed to the stress. To establish a basis for a genetic analysis of this transgenerational stress memory, a broad range of treatments was tested for quantitative effects on homologous recombination in the progeny. Several Arabidopsis lines, transgenic for well-established recombination traps, were exposed to 10 different physical and chemical stress treatments, and scored for the number of somatic homologous recombination (SHR events in the treated generation as well as in the two subsequent generations that were not treated. These numbers were related to the expression level of genes involved in homologous recombination and repair. SHR was enhanced after the majority of treatments, confirming previous data and adding new effective stress types, especially interference with chromatin. Compounds that directly modify DNA stimulated SHR to values exceeding previously described induction rates, concomitant with an induction of genes involved in SHR. In spite of the significant stimulation in the stressed generations, the two subsequent non-treated generations only showed a low and stochastic increase in SHR that did not correlate with the degree of stimulation in the parental plants. Transcripts coding for SHR enzymes generally returned to pre-treatment levels in the progeny. Thus, transgenerational effects on SHR frequency are not a general response to abiotic stress in Arabidopsis and may require special conditions.

  18. CYP2J2-Derived Epoxyeicosatrienoic Acids Suppress Endoplasmic Reticulum Stress in Heart Failure

    Wang, Xingxu; Ni, Li; Yang, Lei; Duan, Quanlu; Chen, Chen; Edin, Matthew L.; Zeldin, Darryl C.; WANG, DAO WEN

    2014-01-01

    Prolonged endoplasmic reticulum (ER) stress causes apoptosis and is associated with heart failure. Whether CYP2J2 and its arachidonic acid metabolites [epoxyeicosatrienoic acids (EETs)] have a protective influence on ER stress and heart failure has not been studied. Assays of myocardial samples from patients with end-stage heart failure showed evidence of ER stress. Chronic infusion of isoproterenol (ISO) or angiotensin II (AngII) by osmotic mini-pump induced cardiac hypertrophy and heart fai...

  19. Folic acid supplementation reduces oxidative stress and hepatic toxicity in rats treated chronically with ethanol

    Lee, Soo-Jung; Kang, Myung-Hee; Min, Hyesun

    2011-01-01

    Folate deficiency and hyperhomocysteinemia are found in most patients with alcoholic liver disease. Oxidative stress is one of the most important mechanisms contributing to homocysteine (Hcy)-induced tissue injury. However it has not been examined whether exogenous administration of folic acid attenuates oxidative stress and hepatic toxicity. The aim of this study was to investigate the in vivo effect of folic acid supplementation on oxidative stress and hepatic toxicity induced by chronic et...

  20. Mechanical stress induces neuroendocrine and immune responses of sea cucumber ( Apostichopus japonicus)

    Tan, Jie; Li, Fenghui; Sun, Huiling; Gao, Fei; Yan, Jingping; Gai, Chunlei; Chen, Aihua; Wang, Qingyin

    2015-04-01

    Grading procedure in routine sea cucumber hatchery production is thought to affect juvenile sea cucumber immunological response. The present study investigated the impact of a 3-min mechanical perturbation mimicking the grading procedure on neuroendocrine and immune parameters of the sea cucumber Apostichopus japonicus. During the application of stress, concentrations of noradrenaline and dopamine in coelomic fluid increased significantly, indicating that the mechanical perturbation resulted in a transient state of stress in sea cucumbers. Coelomocytes concentration in coelomic fluid increased transiently after the beginning of stressing, and reached the maximum in 1 h. Whereas, coelomocytes phagocytosis at 3 min, superoxide anion production from 3 min to 0.5 h, acid phosphatase activity at 0.5 h, and phenoloxidase activity from 3 min to 0.5 h were all significantly down-regulated. All of the immune parameters recovered to baseline levels after the experiment was conducted for 8 h, and an immunostimulation occurred after the stress considering the phagocytosis and acid phosphatase activity. The results suggested that, as in other marine invertebrates, neuroendocrine/immune connections exist in sea cucumber A. japonicus. Mechanical stress can elicit a profound influence on sea cucumber neuroendocrine system. Neuroendocrine messengers act in turn to modulate the immunity functions. Therefore, these effects should be considered for developing better husbandry procedures.

  1. Chronic Heat Stress Induces Immune Response, Oxidative Stress Response, and Apoptosis of Finishing Pig Liver: A Proteomic Approach

    Cui, Yanjun; Hao, Yue; Li, Jielei; Bao, Weiguang; Li, Gan; Gao, Yanli; Gu, Xianhong

    2016-01-01

    Heat stress (HS) negatively affects human health, animal welfare, and livestock production. We analyzed the hepatic proteomes of finishing pigs subjected to chronic heat stress (HS), thermal neutral (TN), and restricted feed intake conditions, identifying differences between direct and indirect (via reduced feed intake) HS. Twenty-four castrated male pigs were randomly allocated to three treatments for three weeks: (1) thermal neutral (TN) (22 °C) with ad libitum feeding; (2) chronic HS (30 °C) with ad libitum feeding; and (3) TN, pair-fed to HS intake (PF). Hepatic proteome analysis was conducted using two-dimensional gel electrophoresis and mass spectrometry. Both HS and PF significantly reduced liver weight (p proteins were differentially abundant when comparing HS with TN (37), PF with TN (29), and HS with PF (16). These proteins are involved in heat shock response and immune defense, oxidative stress response, cellular apoptosis, metabolism, signal transduction, and cytoskeleton. We also observed increased abundance of proteins and enzymes associated with heat shock response and immune defense, reduced the redox state, enhanced multiple antioxidant abilities, and increased apoptosis in HS liver. Heat-load, independent of reduced feed intake, induced an innate immune response, while food restriction caused stress and cellular apoptosis. Our results provide novel insights into the effects of chronic HS on liver. PMID:27187351

  2. Molecular Responses of Groundnut (Arachis hypogea L. to Zinc Stress

    A. John De Britto

    2013-08-01

    Full Text Available Heavy metals are important environmental pollutants and their toxicity is a problem of increasing significance for ecological, evolutionary and environmental reasons. The interference of germination related proteins by heavy metals has not been well documented at the proteomic and genomic level. In the current study, molecular responses of germinating groundnut seeds were investigated under Zinc stress. The SDS-PAGE showed the preliminary changes in the polypeptides patterns under Zinc stress. Restriction digestion banding pattern of EcoRI and Hind III enzymes showed distinct banding pattern in the treated plants.

  3. Acute psychological stress induces short-term variable immune response.

    Breen, Michael S; Beliakova-Bethell, Nadejda; Mujica-Parodi, Lilianne R; Carlson, Joshua M; Ensign, Wayne Y; Woelk, Christopher H; Rana, Brinda K

    2016-03-01

    In spite of advances in understanding the cross-talk between the peripheral immune system and the brain, the molecular mechanisms underlying the rapid adaptation of the immune system to an acute psychological stressor remain largely unknown. Conventional approaches to classify molecular factors mediating these responses have targeted relatively few biological measurements or explored cross-sectional study designs, and therefore have restricted characterization of stress-immune interactions. This exploratory study analyzed transcriptional profiles and flow cytometric data of peripheral blood leukocytes with physiological (endocrine, autonomic) measurements collected throughout the sequence of events leading up to, during, and after short-term exposure to physical danger in humans. Immediate immunomodulation to acute psychological stress was defined as a short-term selective up-regulation of natural killer (NK) cell-associated cytotoxic and IL-12 mediated signaling genes that correlated with increased cortisol, catecholamines and NK cells into the periphery. In parallel, we observed down-regulation of innate immune toll-like receptor genes and genes of the MyD88-dependent signaling pathway. Correcting gene expression for an influx of NK cells revealed a molecular signature specific to the adrenal cortex. Subsequently, focusing analyses on discrete groups of coordinately expressed genes (modules) throughout the time-series revealed immune stress responses in modules associated to immune/defense response, response to wounding, cytokine production, TCR signaling and NK cell cytotoxicity which differed between males and females. These results offer a spring-board for future research towards improved treatment of stress-related disease including the impact of stress on cardiovascular and autoimmune disorders, and identifies an immune mechanism by which vulnerabilities to these diseases may be gender-specific. PMID:26476140

  4. Mongolian Almond (Prunus mongolica Maxim): The Morpho-Physiological, Biochemical and Transcriptomic Response to Drought Stress.

    Wang, Jǖgang; Zheng, Rong; Bai, Shulan; Gao, Xiaomin; Liu, Min; Yan, Wei

    2015-01-01

    Prunus mongolica Maxim, which is widely established in the Gobi Desert, shows extreme tolerance to drought. However, there is a lack of available transcriptomic resources for this species related to its response to water deficiency. To investigate the mechanisms that allow P. mongolica to maintain growth in extremely arid environments, the response of P. mongolica seedlings to drought stress was analyzed using morphological, physiological, biochemical and high-throughput sequencing approaches. We generated 28,713,735 and 26,650,133 raw reads from no-stress control and drought-stressed P. mongolica seedlings, respectively. In total, we obtained 67,352 transcripts with an average length of 874.44 bp. Compared with the no-stress control, 3,365 transcripts were differentially expressed in the drought-stressed seedlings, including 55.75% (1,876 transcripts) up-regulated and 44.25% (1,489 transcripts) down-regulated transcripts. The photosynthesis response showed a decreasing tendency under drought stress, but the changes in the levels of hormones (auxins, cytokinins and abscisic acid) resulted in the closing of stomata and decreased cell enlargement and division; these changes were effective for promoting P. mongolica survival in Gobi Desert. Next, we analyzed the aquaporin and superoxide dismutase gene families due to their importance in plant resistance to drought stress. We found that all of the plasma membrane intrinsic protein transcripts were down-regulated in the drought-stressed treatment, whereas drought did not affect the expression of nodulin intrinsic protein or small basic intrinsic protein transcripts in P. mongolica seedlings. In addition, activation of iron superoxide dismutase transcription and enhanced transcription of manganese superoxide dismutase were observed in P. mongolica to promote tolerance of drought stress. This study identified drought response genes in P. mongolica seedlings. Our results provide a significant contribution to the

  5. Mongolian Almond (Prunus mongolica Maxim: The Morpho-Physiological, Biochemical and Transcriptomic Response to Drought Stress.

    Jǖgang Wang

    Full Text Available Prunus mongolica Maxim, which is widely established in the Gobi Desert, shows extreme tolerance to drought. However, there is a lack of available transcriptomic resources for this species related to its response to water deficiency. To investigate the mechanisms that allow P. mongolica to maintain growth in extremely arid environments, the response of P. mongolica seedlings to drought stress was analyzed using morphological, physiological, biochemical and high-throughput sequencing approaches. We generated 28,713,735 and 26,650,133 raw reads from no-stress control and drought-stressed P. mongolica seedlings, respectively. In total, we obtained 67,352 transcripts with an average length of 874.44 bp. Compared with the no-stress control, 3,365 transcripts were differentially expressed in the drought-stressed seedlings, including 55.75% (1,876 transcripts up-regulated and 44.25% (1,489 transcripts down-regulated transcripts. The photosynthesis response showed a decreasing tendency under drought stress, but the changes in the levels of hormones (auxins, cytokinins and abscisic acid resulted in the closing of stomata and decreased cell enlargement and division; these changes were effective for promoting P. mongolica survival in Gobi Desert. Next, we analyzed the aquaporin and superoxide dismutase gene families due to their importance in plant resistance to drought stress. We found that all of the plasma membrane intrinsic protein transcripts were down-regulated in the drought-stressed treatment, whereas drought did not affect the expression of nodulin intrinsic protein or small basic intrinsic protein transcripts in P. mongolica seedlings. In addition, activation of iron superoxide dismutase transcription and enhanced transcription of manganese superoxide dismutase were observed in P. mongolica to promote tolerance of drought stress. This study identified drought response genes in P. mongolica seedlings. Our results provide a significant contribution

  6. Protective Effects of Ferulic Acid against Heat Stress-Induced Intestinal Epithelial Barrier Dysfunction In Vitro and In Vivo.

    Shasha He

    Full Text Available Heat stress is important in the pathogenesis of intestinal epithelial barrier dysfunction. Ferulic acid (FA, a phenolic acid widely found in fruits and vegetables, can scavenge free radicals and activate cell stress responses. This study is aimed at investigating protective effects of FA on heat stress-induced dysfunction of the intestinal epithelial barrier in vitro and in vivo. Intestinal epithelial (IEC-6 cells were pretreated with FA for 4 h and then exposed to heat stress. Heat stress caused decreased transepithelial electrical resistance (TER and increased permeability to 4-kDa fluorescein isothiocyanate (FITC-dextran (FD4. Both effects were inhibited by FA in a dose-dependent manner. FA significantly attenuated the decrease in occludin, ZO-1 and E-cadherin expression observed with heat stress. The distortion and redistribution of occludin, ZO-1 and E-cadherin proteins were also effectively prevented by FA pretreatment. Moreover, heat stress diminished electron-dense material detected in tight junctions (TJs, an effect also alleviated by FA in a dose-dependent manner. In an in vivo heat stress model, FA (50 mg/kg was administered to male Sprague-Dawley rats for 7 consecutive days prior to exposure to heat stress. FA pretreatment significantly attenuated the effects of heat stress on the small intestine, including the increased FD4 permeability, disrupted tight junctions and microvilli structure, and reduced occludin, ZO-1 and E-cadherin expression. Taken together, our results demonstrate that FA pretreatment is potentially protective against heat stress-induced intestinal epithelial barrier dysfunction.

  7. Elevated oxidative stress and sensorimotor deficits but normal cognition in mice that cannot synthesize ascorbic acid

    Harrison, Fiona E.; Yu, S Sarah; Van Den Bossche, Kristen L; Li, Liying; May, James M.; McDonald, Michael P.

    2008-01-01

    Oxidative stress is implicated in the cognitive deterioration associated with normal aging as well as neurodegenerative disorders such as Alzheimer’s and Parkinson's diseases. We investigated the effect of ascorbic acid (vitamin C) on oxidative stress, cognition and motor abilities in mice null for gulono-γ-lactone oxidase (Gulo). Gulo−/− mice are unable to synthesize ascorbic acid and depend on dietary ascorbic acid for survival. Gulo−/− mice were given supplements that provided them either ...

  8. Acid Stress-Mediated Metabolic Shift in Lactobacillus sanfranciscensis LSCE1 ▿

    Serrazanetti, Diana I.; Ndagijimana, Maurice; Sado-Kamdem, Sylvain L.; Corsetti, Aldo; Vogel, Rudi F.; Ehrmann, Matthias; Guerzoni, M. Elisabetta

    2011-01-01

    Lactobacillus sanfranciscensis LSCE1 was selected as a target organism originating from recurrently refreshed sourdough to study the metabolic rerouting associated with the acid stress exposure during sourdough fermentation. In particular, the acid stress induced a metabolic shift toward overproduction of 3-methylbutanoic and 2-methylbutanoic acids accompanied by reduced sugar consumption and primary carbohydrate metabolite production. The fate of labeled leucine, the role of different nutrie...

  9. Proteomic response of wheat embryos to fosthiazate stress in a protected vegetable soil

    Chunyan Yin; Ying Teng; Yongming Luo; Peter Christie

    2012-01-01

    A proteomic analysis of wheat defense response induced by the widely used organophosphorus nematicide fosthiazate is reported.Seed germination and two-dimensional gel electrophoresis (2-DE) experiments were performed using a Chinese wheat cultivar,Zhenmai No.5.Root and shoot elongation decreased but thiobarbituric acid reactive substances (TBARS) content in embryos increased with increasing pesticide concentration.More than 1000 protein spots were reproducibly detected in each silver-stained gel.Thirty-seven protein spots with at least 2-fold changes were identified using MALDI-TOF MS/MS analysis.Of these,24 spots were up-regulated and 13 were down-regulated.Proteins identified included some well-known classical stress responsive proteins under abiotic or biotic stresses as well as some unusual responsive proteins.Ten responsive proteins were reported for the first time at the proteomic level,including fatty acyl CoA reductase,dihydrodipicolinate synthase,DEAD-box ATPase-RNA-helicase,fimbriata-like protein,waxy B1,rust resistance kinase Lrl0,putative In2.1 protein,retinoblastoma-related protein 1,pollen allergen-like protein and S-adenosyl-Lmethionine:phosphoethanolamine N-methyltransferase.The proteins identified were involved in several processes such as metabolism,defense/detoxification,cell structure/cell growth,signal transduction/transcription,photosynthesis and energy.Seven candidate proteins were further analyzed at the mRNA level by RT-PCR to compare transcript and protein accumulation patterns,revealing that not all the genes were correlated well with the protein level.Identification of these responsive proteins may provide new insight into the molecular basis of the fosthiazate-stress response in the early developmental stages of plants and may be useful in stress monitoring or stress-tolerant crop breeding for environmentally friendly agricultural production.

  10. Interactions between polyamines and abiotic stress pathway responses unraveled by transcriptome analysis of polyamine overproducers.

    Marco, Francisco; Alcázar, Rubén; Tiburcio, Antonio F; Carrasco, Pedro

    2011-11-01

    Plant development and productivity are negatively regulated by adverse environmental conditions. The identification of stress-regulatory genes, networks, and signaling molecules should allow the development of novel strategies to obtain tolerant plants. Polyamines (PAs) are polycationic compounds with a recognized role in plant growth and development, as well as in abiotic and biotic stress responses. During the last years, knowledge on PA functions has been achieved using genetically modified plants with altered PA levels. In this review, we combine the information obtained from global transcriptome analyses in transgenic Arabidopsis plants with altered putrescine or spermine levels. Comparison of common and specific gene networks affected by elevation of endogenous PAs, support the view that these compounds actively participate in stress signaling through intricate crosstalks with abscisic acid (ABA), Ca(2+) signaling and other hormonal pathways in plant defense and development. PMID:22011340

  11. ABA biosynthesis defective mutants reduce some free amino acids accumulation under drought stress in tomato leaves in comparison with Arabidopsis plants tissues

    Adnan Ali Al.Asbahi

    2012-05-01

    Full Text Available The ability of plants to tolerate drought conditions is crucial for plant survival and crop production worldwide. The present data confirm previous findings reported existence of a strong relation between abscisic acid (ABA content and amino acid accumulation as response water stress which is one of the most important defense mechanism activated during water stress in many plant species. Therefore, free amino acids were measured to determine any changes in the metabolite pool in relation to ABA content. The ABA defective mutants of Arabidopsis plants were subjected to leaf dehydration for Arabidopsis on Whatman 3 mm filter paper at room temperature while, tomato mutant plants were subjected to drought stresses for tomato plants by withholding water. To understand the signal transduction mechanisms underlying osmotic stress-regulating gene induction and activation of osmoprotectant free amino acid synthesizing genes, we carried out a genetic screen to isolate Arabidopsis mutants defective in ABA biosynthesis under drought stress conditions. The present results revealed an accumulation of specific free amino acid in water stressed tissues in which majority of free amino acids are increased especially those playing an osmoprotectant role such as proline and glycine. Drought stress related Amino acids contents are significantly reduced in the mutants under water stress condition while they are increased significantly in the wild types plants. The exhibited higher accumulation of other amino acids under stressed condition in the mutant plants suggest that, their expressions are regulated in an ABA independent pathways. In addition, free amino acids content changes during water stress condition suggest their contribution in drought toleration as common compatible osmolytes.

  12. Ethylene response factor Sl-ERF.B.3 is responsive to abiotic stresses and mediates salt and cold stress response regulation in tomato.

    Klay, Imen; Pirrello, Julien; Riahi, Leila; Bernadac, Anne; Cherif, Ameur; Bouzayen, Mondher; Bouzid, Sadok

    2014-01-01

    Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3) gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor) family. Our results of real-time RT-PCR showed that Sl-ERF.B.3 is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role of Sl-ERF.B.3 in plant response to separate salinity and cold, a comparative study between wild type and two Sl-ERF.B.3 antisense transgenic tomato lines was achieved. Compared with wild type, Sl-ERF.B.3 antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisense Sl-ERF.B.3 in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest that Sl-ERF.B.3 gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity. PMID:25215313

  13. Ethylene Response Factor Sl-ERF.B.3 Is Responsive to Abiotic Stresses and Mediates Salt and Cold Stress Response Regulation in Tomato

    Imen Klay

    2014-01-01

    Full Text Available Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3 gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor family. Our results of real-time RT-PCR showed that Sl-ERF.B.3 is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role of Sl-ERF.B.3 in plant response to separate salinity and cold, a comparative study between wild type and two Sl-ERF.B.3 antisense transgenic tomato lines was achieved. Compared with wild type, Sl-ERF.B.3 antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisense Sl-ERF.B.3 in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest that Sl-ERF.B.3 gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity.

  14. Transcriptome Analysis of Spartina pectinata in Response to Freezing Stress.

    Nah, Gyoungju; Lee, Moonsub; Kim, Do-Soon; Rayburn, A Lane; Voigt, Thomas; Lee, D K

    2016-01-01

    Prairie cordgrass (Spartina pectinata), a perennial C4 grass native to the North American prairie, has several distinctive characteristics that potentially make it a model crop for production in stressful environments. However, little is known about the transcriptome dynamics of prairie cordgrass despite its unique freezing stress tolerance. Therefore, the purpose of this work was to explore the transcriptome dynamics of prairie cordgrass in response to freezing stress at -5°C for 5 min and 30 min. We used a RNA-sequencing method to assemble the S. pectinata leaf transcriptome and performed gene-expression profiling of the transcripts under freezing treatment. Six differentially expressed gene (DEG) groups were categorized from the profiling. In addition, two major consecutive orders of gene expression were observed in response to freezing; the first being the acute up-regulation of genes involved in plasma membrane modification, calcium-mediated signaling, proteasome-related proteins, and transcription regulators (e.g., MYB and WRKY). The follow-up and second response was of genes involved in encoding the putative anti-freezing protein and the previously known DNA and cell-damage-repair proteins. Moreover, we identified the genes involved in epigenetic regulation and circadian-clock expression. Our results indicate that freezing response in S. pectinata reflects dynamic changes in rapid-time duration, as well as in metabolic, transcriptional, post-translational, and epigenetic regulation. PMID:27032112

  15. Physical and psychological stress have similar effects on gastric acid and pepsin secretions in rat

    Ehsan Salimi

    2011-05-01

    Full Text Available Stress is one of the most important health and social problems. Previous studies have demonstrated stress influence on the clinical course of a number of gastrointestinal diseases, but its physical and psychological effects on gastric acid and pepsin secretions are largely unknown. 48 male wistar rats weighing 200-250 gr were used in this study. Animals were divided into 6 groups (n=8; Control, Physical stress, Psychological stress, L-NAME+ Physical stress and L-NAME+ Psychological stress groups. In this study, electrical shock generated in a communication box was used as physical shock and the emotional stress was as psychological stress.Gastric juice was collected by washout technique. Acid output was also measured by digital titrator. Gastric pepsin and nitric oxide (NO metabolites were quantified using Anson and Griess micro assay methods respectively.Basal and stimulated gastric acid and pepsin in physical and psychological stress groups were significantly more than others. NO metabolites level of gastric tissue in physical and psychological stress groups (286.9 ± 5.8, 287.7 ± 5.7 μmol/gr weight wet tissue, respectively were significantly more than other groups. But no significant differences among basal and stimulated gastric acid, pepsin and NO metabolites level were seen in physical and psychological stress groups.

  16. EFFECT OF DEXMEDETOMIDINE ON STRESS RESPONSE TO ENDOTRACHEAL INTUBATION

    Sathee Devi

    2015-03-01

    Full Text Available Laryngoscopy as well as tracheal intubation cause changes in the hemodynamics of the patients. A similar set of hemodynamic events have been noticed by various studies during tracheal extubation also. These responses may produce myocardial ischemia or infarction in susceptible patients. Various agents like lignocaine, e smolol, sodium nitropruside, nitroglycerine etc . have been proved to be effective in attenuating these response. Dexmedetomidine, an alpha 2 agonist have been successfully used for attenuating the sympathetic response during endotracheal extubation. We conducted an observational study to examine the rol e of dexmedetomidine on hemodynamic response during endotracheal intubation. A bolus dose of Dexmedetomidine 0.7 - 1 mcg /kg over 10mts prior to endotracheal intubation provided hemodynamic stability than inj. lignocaine hydrochloride ( G old standard .This c an prove beneficial for patients where the stress response to intubation is highly undesirable.

  17. Deciphering hepatocellular responses to metabolic and oncogenic stress

    Kathrina L. Marcelo

    2015-08-01

    Full Text Available Each cell type responds uniquely to stress and fractionally contributes to global and tissue-specific stress responses. Hepatocytes, liver macrophages (MΦ, and sinusoidal endothelial cells (SEC play functionally important and interdependent roles in adaptive processes such as obesity and tumor growth. Although these cell types demonstrate significant phenotypic and functional heterogeneity, their distinctions enabling disease-specific responses remain understudied. We developed a strategy for the simultaneous isolation and quantification of these liver cell types based on antigenic cell surface marker expression. To demonstrate the utility and applicability of this technique, we quantified liver cell-specific responses to high-fat diet (HFD or diethylnitrosamine (DEN, a liver-specific carcinogen, and found that while there was only a marginal increase in hepatocyte number, MΦ and SEC populations were quantitatively increased. Global gene expression profiling of hepatocytes, MΦ and SEC identified characteristic gene signatures that define each cell type in their distinct physiological or pathological states. Integration of hepatic gene signatures with available human obesity and liver cancer microarray data provides further insight into the cell-specific responses to metabolic or oncogenic stress. Our data reveal unique gene expression patterns that serve as molecular “fingerprints” for the cell-centric responses to pathologic stimuli in the distinct microenvironment of the liver. The technical advance highlighted in this study provides an essential resource for assessing hepatic cell-specific contributions to metabolic and oncogenic stress, information that could unveil previously unappreciated molecular mechanisms for the cellular crosstalk that underlies the continuum from metabolic disruption to obesity and ultimately hepatic cancer.

  18. The plant response:stress in the daily environment

    FERGUSON Ian B.

    2004-01-01

    @@STRESS IS NORMAL Like animals, plants have evolved to survive in almost every climatic and environmental niche available. They have, however, evolved more sophisticated and varied methods to enable them to survive environmental changes in light, temperature, atmosphere composition, water and nutrients and salinity. This, in part, is necessary because of the sessile nature of plants; they do not have the ability to move to more favourable environments. Stress conditions that plants encounter are not always as rare or unusual as we might at first think. The most common environmental variables, necessary for growth, can impose significant stresses on the plant. But should we think of these as unusual and extreme or just part of the normal diurnal responses experienced by the plant?

  19. Endoplasmic Reticulum Stress Sensing in the Unfolded Protein Response

    Gardner, Brooke M.; Pincus, David; Gotthardt, Katja; Gallagher, Ciara M.; Walter, Peter

    2013-01-01

    Secretory and transmembrane proteins enter the endoplasmic reticulum (ER) as unfolded proteins and exit as either folded proteins in transit to their target organelles or as misfolded proteins targeted for degradation. The unfolded protein response (UPR) maintains the protein-folding homeostasis within the ER, ensuring that the protein-folding capacity of the ER meets the load of client proteins. Activation of the UPR depends on three ER stress sensor proteins, Ire1, PERK, and ATF6. Although the consequences of activation are well understood, how these sensors detect ER stress remains unclear. Recent evidence suggests that yeast Ire1 directly binds to unfolded proteins, which induces its oligomerization and activation. BiP dissociation from Ire1 regulates this oligomeric equilibrium, ultimately modulating Ire1’s sensitivity and duration of activation. The mechanistic principles of ER stress sensing are the focus of this review. PMID:23388626

  20. Quorum sensing regulates the osmotic stress response in Vibrio harveyi.

    van Kessel, Julia C; Rutherford, Steven T; Cong, Jian-Ping; Quinodoz, Sofia; Healy, James; Bassler, Bonnie L

    2015-01-01

    Bacteria use a chemical communication process called quorum sensing to monitor cell density and to alter behavior in response to fluctuations in population numbers. Previous studies with Vibrio harveyi have shown that LuxR, the master quorum-sensing regulator, activates and represses >600 genes. These include six genes that encode homologs of the Escherichia coli Bet and ProU systems for synthesis and transport, respectively, of glycine betaine, an osmoprotectant used during osmotic stress. Here we show that LuxR activates expression of the glycine betaine operon betIBA-proXWV, which enhances growth recovery under osmotic stress conditions. BetI, an autorepressor of the V. harveyi betIBA-proXWV operon, activates the expression of genes encoding regulatory small RNAs that control quorum-sensing transitions. Connecting quorum-sensing and glycine betaine pathways presumably enables V. harveyi to tune its execution of collective behaviors to its tolerance to stress. PMID:25313392

  1. Transcriptional Analysis of Normal Human Fibroblast Responses to Microgravity Stress

    Yongqing Liu; Eugenia Wang

    2008-01-01

    To understand the molecular mechanism (s) of how spaceflight affects cellular signaling pathways, quiescent normal human WI-38 fibroblasts were flown on the STS-93 space shuttle mission. Subsequently, RNA samples from the space flown and ground-control cells were used to construct two cDNA libraries, which were then processed for suppression subtractive hybridization (SSH) to identify spaceflight-specific gene expression. The SSH data show that key genes related to oxidative stress, DNA repair, and fatty acid oxidation are activated by spaceflight, suggesting the induction of cellular oxidative stress. This is further substantiated by the up-regulation of neuregulin 1 and the calcium-binding protein calmodulin 2. Another obvious stress sign is that spaceflight evokes the Ras/mitogen-activated protein kinase and phosphatidylinositol-3 kinase signaling pathways, along with up-regulating several G1-phase cell cycle traverse genes. Other genes showing up regulation of expression are involved in protein synthesis and pro-apoptosis, as well as pro-survival. Interactome analysis of functionally related genes shows that c-Myc is the "hub" for those genes showing significant changes. Hence, our results suggest that microgravity travel may impact changes in gene expression mostly associated with cellular stress signaling, directing cells to either apoptotic death or premature senescence.

  2. Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

    Alessandra da Silva Dantas

    2015-02-01

    Full Text Available Candida albicans is a major fungal pathogen of humans, causing approximately 400,000 life-threatening systemic infections world-wide each year in severely immunocompromised patients. An important fungicidal mechanism employed by innate immune cells involves the generation of toxic reactive oxygen species (ROS, such as superoxide and hydrogen peroxide. Consequently, there is much interest in the strategies employed by C. albicans to evade the oxidative killing by macrophages and neutrophils. Our understanding of how C. albicans senses and responds to ROS has significantly increased in recent years. Key findings include the observations that hydrogen peroxide triggers the filamentation of this polymorphic fungus and that a superoxide dismutase enzyme with a novel mode of action is expressed at the cell surface of C. albicans. Furthermore, recent studies have indicated that combinations of the chemical stresses generated by phagocytes can actively prevent C. albicans oxidative stress responses through a mechanism termed the stress pathway interference. In this review, we present an up-date of our current understanding of the role and regulation of oxidative stress responses in this important human fungal pathogen.

  3. Low dose radiation induced adaptive response upon salt stress and vacuum stress: a possible mechanism for the effect of saddle-like dose response curve

    To explore mechanism for the effect of saddle-like dose-response curve, the relationship of irradiation-vacuum stress, and irradiation-salt stress, was investigated with rice seeds irradiated to 60-560 Gy by 60Co γ-rays. The dose-response curve was simulated based on seedling height data, which showed obedient to linear-quadratic model. During germination,the irradiated rice seeds were stressed by 10-3 Pa vacuum, or by NaCl in different concentrations. After that, the dose-response curve manifested a saddle-like shape. The results indicate that while low dose irradiation could retard seedling growth synergistically with vacuum stress and salt stress, it could also induce adaptive response upon vacuum stress and salt stress. Low dose irradiation induced adaptive response upon environmental adverse factors could contribute to the mechanism for the effect of saddle-like dose-response curve. (authors)

  4. Proteomic Study for Responses to Cadmium Stress in Rice Seedlings

    GE Cai-lin; WANG Ze-gang; WAN Ding-zhen; DING Yan; WANG Yu-long; SHANG Qi; LUO Shi-shi

    2009-01-01

    A proteomic approach including two-dimensional electrophoresis and mass spectrometric (MALDI-TOF MS) analyses was used to investigate the responses to cadmium (Cd) stress in seedlings of rice (Oryza sativa L.) varieties Shanyou 63 and Aizaizhan. Cd stress significantly inhibited root and shoot growth, and affected the global proteome in rice roots and leaves, which induced or upregulated the expression of corresponding proteins in rice roots and leaves when rice seedlings were exposed to 0.1 or 1.0 mmol/L Cd. The Cd-induced proteins are involved in chelation and compartmentation of Cd, elimination of active oxygen free radicals, detoxification of toxic substances, degradation of denatured proteins or inactivated enzymes, regulation of physiologic metabolism and induction of pathogenesis-related proteins. Comparing the Cd-induced proteins between the two varieties, the β-glucosidase and pathogenesis-related protein family 10 proteins were more drastically induced by Cd stress in roots and leaves of Aizaizhan, and the UDP-glucose protein transglucosylase and translational elongation factor Tu were induced by 0.1 mmol/L Cd stress in roots of Shanyou 63. This may be one of the important mechanisms for higher tolerance to Cd stress in Shanyou 63 than in Aizaizhan.

  5. Microbial modulation of behavior and stress responses in zebrafish larvae.

    Davis, Daniel J; Bryda, Elizabeth C; Gillespie, Catherine H; Ericsson, Aaron C

    2016-09-15

    The influence of the microbiota on behavior and stress responses is poorly understood. Zebrafish larvae have unique characteristics that are advantageous for neuroimmune research, however, they are currently underutilized for such studies. Here, we used germ-free zebrafish to determine the effects of the microbiota on behavior and stress testing. The absence of a microbiota dramatically altered locomotor and anxiety-related behavior. Additionally, characteristic responses to an acute stressor were also obliterated in larvae lacking exposure to microbes. Lastly, treatment with the probiotic Lactobacillus plantarum was sufficient to attenuate anxiety-related behavior in conventionally-raised zebrafish larvae. These results underscore the importance of the microbiota in communicating to the CNS via the microbiome-gut-brain axis and set a foundation for using zebrafish larvae for neuroimmune research. PMID:27217102

  6. Behaviour and stress responses in horses with gastric ulceration

    Malmkvist, Jens; Poulsen, Janne Møller; Luthersson, Nanna;

    2012-01-01

    Only little is known about behaviour and stress responses in horses with gastric ulceration, despite the high prevalence of this condition. Our objectives in the present study was to (i) describe the severity of gastric ulceration in horses, housed under relatively standardised conditions, and (ii......) to investigate whether horses with severe glandular gastric ulceration have increased baseline and response concentration of stress hormones and behave differently than control horses. We investigated stomachs of 96 horses at one stud, and compared an ulcer group (n = 30; with severe lesions in the glandular.......2% and non-glandular lesions in 40.6% of the horses. The amount of starch in the feed (P = 0.006) and paternal stallion (P = 0.031) influenced ulceration in the non-glandular region only; it should be noted that our study does not allow for separating hereditary from environmental influences, as offspring...

  7. System-level understanding of the potential acid-tolerance components of Acidithiobacillus thiooxidans ZJJN-3 under extreme acid stress.

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2015-09-01

    In previous study, two extremely acidophilic strains Acidithiobacillus thiooxidans ZJJN-3 (collection site: bioleaching leachate) and ZJJN-5 (collection site: bioleaching wastewater) were isolated from a typical industrial bio-heap in China. Here, we unraveled the potential acid-tolerance components of ZJJN-3 by comparing the physiological differences with ZJJN-5 under different acid stresses. The parameters used for comparison included intracellular pH (pHin), capsule morphology, fatty acid composition of cell membrane, transcription of key molecular chaperones, H(+)-ATPase activities and NAD(+)/NADH ratio. It was indicated that the acid-tolerance of A. thiooxidans ZJJN-3 was systematically regulated. Capsule first thickened and then shed off along with increased acid stress. Cell membrane maintained the intracellular stability by up-regulating the proportion of unsaturated fatty acid and cyclopropane fatty acids. Meanwhile, the transcription of key repair molecular chaperones (GrpE-DnaK-DnaJ) was up-regulated by 2.2-3.5 folds for ensuring the proper folding of peptide. Moreover, low pHin promoted ZJJN-3 to biosynthesize more H(+)-ATPase for pumping H(+) out of cells. Furthermore, the NAD(+)/NADH ratio increased due to the decreased H(+) concentration. Based on the above physiological analysis, the potential acid-tolerance components of A. thiooxidans ZJJN-3 were first proposed and it would be useful for better understanding how these extremophiles responded to the high acid stress. PMID:26264736

  8. Genome-scale cold stress response regulatory networks in ten Arabidopsis thaliana ecotypes

    Barah, Pankaj; Jayavelu, Naresh Doni; Rasmussen, Simon;

    2013-01-01

    available from Arabidopsis thaliana 1001 genome project, we further investigated sequence polymorphisms in the core cold stress regulon genes. Significant numbers of non-synonymous amino acid changes were observed in the coding region of the CBF regulon genes. Considering the limited knowledge about......BACKGROUND: Low temperature leads to major crop losses every year. Although several studies have been conducted focusing on diversity of cold tolerance level in multiple phenotypically divergent Arabidopsis thaliana (A. thaliana) ecotypes, genome-scale molecular understanding is still lacking....... RESULTS: In this study, we report genome-scale transcript response diversity of 10 A. thaliana ecotypes originating from different geographical locations to non-freezing cold stress (10°C). To analyze the transcriptional response diversity, we initially compared transcriptome changes in all 10 ecotypes...

  9. RpoS differentially affects the general stress response and biofilm formation in the endophytic Serratia plymuthica G3.

    Liu, Xiaoguang; Wu, Yan; Chen, Yuanyuan; Xu, Fang; Halliday, Nigel; Gao, Kexiang; Chan, Kok Gan; Cámara, Miguel

    2016-04-01

    The σ(S) subunit RpoS of RNA polymerase functions as a master regulator of the general stress response in Escherichia coli and related bacteria. RpoS has been reported to modulate biocontrol properties in the rhizobacterium Serratia plymuthica IC1270. However, the role of RpoS in the stress response and biofilm formation in S. plymuthica remains largely unknown. Here we studied the role of RpoS from an endophytic S. plymuthica G3 in regulating these phenotypes. Mutational analysis demonstrated that RpoS positively regulates the global stress response to acid or alkaline stresses, oxidative stress, hyperosmolarity, heat shock and carbon starvation, in addition to proteolytic and chitinolytic activities. Interestingly, rpoS mutations resulted in significantly enhanced swimming motility, biofilm formation and production of the plant auxin indole-3-acetic acid (IAA), which may contribute to competitive colonization and environmental fitness for survival. These findings provide further insight into the strain-specific role of RpoS in the endophytic strain G3 of S. plymuthica, where it confers resistance to general stresses encountered within the plant environment. The heterogeneous functionality of RpoS in rhizosphere and endophytic S. plymuthica populations may provide a selective advantage for better adaptation to various physiological and environmental stresses. PMID:26671319

  10. Depressive Symptoms Enhance Stress-induced Inflammatory Responses

    Fagundes, Christopher P.; Glaser, Ronald; Hwang, Beom Seuk; Malarkey, William B.; Kiecolt-Glaser, Janice K.

    2012-01-01

    Depression is a risk factor for morbidity and mortality, and immune dysregulation may be partially responsible for this link. Proinflammatory cytokines such as interleukin 6 (IL-6) are reliable predictors of quality of life, morbidity, and many causes of mortality. The current study evaluated relationships between depressive symptoms, as assessed by the CES-D, and stress-induced inflammation. The participants, 138 healthy adults, were evaluated at rest, and after a standardized laboratory spe...

  11. Epigenetic responses to drought stress in rice (Oryza sativa L.)

    Gayacharan; Joel, A. John

    2013-01-01

    Cytosine methylation polymorphism plays a key role in gene regulation, mainly in expression of genes in crop plants. The differential expression of cytosine methylation over drought stress response was analyzed in rice using drought susceptible but agronomically superior lines IR 20 and CO 43, and drought tolerant genotypes PL and PMK 3 and their F1 hybrids. The parents and hybrids were subjected to two moisture regimes viz., one under drought condition and another under control condition. Th...

  12. Caenorhabditis elegans stress related gene responses to selected pesticides

    Antoniou-Kourounioti, Melissa

    2010-01-01

    Pesticides are used widely and more than 2 million tons are released in the environment annually (data for 2000-2001, Kiely 2004). Details of their toxicity towards non-target organisms, are not complete for many of these pesticides and serious environmental issues have previously arisen as a result (e.g. effects of DDT on reproduction of wild birds). Unfavourable conditions, including the presence of toxicants, can induce the stress response pathways through which an organism attempts t...

  13. Nitrosative and oxidative stress responses in fungal pathogenicity

    Brown, Alistair JP; Haynes, Ken; Quinn, Janet

    2009-01-01

    Fungal pathogenicity has arisen in polyphyletic manner during evolution, yielding fungal pathogens with diverse infection strategies and with differing degrees of evolutionary adaptation to their human host. Not surprisingly, these fungal pathogens display differing degrees of resistance to the reactive oxygen and nitrogen species used by human cells to counteract infection. Furthermore, whilst evolutionarily conserved regulators, such as Hog1, are central to such stress responses in many fun...

  14. Predicting Performance Under Stressful Conditions Using Galvanic Skin Response

    Mundell, Carter; Vielma, Juan Pablo; Zaman, Tauhid

    2016-01-01

    The rapid growth of the availability of wearable biosensors has created the opportunity for using biological signals to measure worker performance. An important question is how to use such signals to not just measure, but actually predict worker performance on a task under stressful and potentially high risk conditions. Here we show that the biological signal known as galvanic skin response (GSR) allows such a prediction. We conduct an experiment where subjects answer arithmetic questions und...

  15. Identification of Novel Stress-responsive Transcription Factor Genes in Rice by cDNA Array Analysis

    Cong-Qing Wu; Hong-Hong Hu; Ya Zeng; Da-Cheng Liang; Ka-Bin Xie; Jian-Wei Zhang; Zhao-Hui Chu; Li-Zhong Xiong

    2006-01-01

    Numerous studies have shown that array of transcription factors has a role in regulating plant responses to environmental stresses. Only a small portion of them however, have been identified or characterized.More than 2 300 putative transcription factors were predicted in the rice genome and more than half of them were supported by expressed sequences. With an attempt to identify novel transcription factors involved in the stress responses, a cDNA array containing 753 putative rice transcription factors was generated to analyze the transcript profiles of these genes under drought and salinity stresses and abscisic acid treatment at seedling stage of rice. About 80% of these transcription factors showed detectable levels of transcript in seedling leaves. A total of 18 up-regulated transcription factors and 29 down-regulated transcription factors were detected with the folds of changes from 2.0 to 20.5 in at least one stress treatment.Most of these stress-responsive genes have not been reported and the expression patterns for five genes under stress conditions were further analyzed by RNA gel blot analysis. These novel stress-responsive transcription factors provide new opportunities to study the regulation of gene expression in plants under stress conditions.

  16. Genome-wide expression analysis offers new insights into the origin and evolution of Physcomitrella patens stress response

    Khraiwesh, Basel

    2015-11-30

    Changes in the environment, such as those caused by climate change, can exert stress on plant growth, diversity and ultimately global food security. Thus, focused efforts to fully understand plant response to stress are urgently needed in order to develop strategies to cope with the effects of climate change. Because Physcomitrella patens holds a key evolutionary position bridging the gap between green algae and higher plants, and because it exhibits a well-developed stress tolerance, it is an excellent model for such exploration. Here, we have used Physcomitrella patens to study genome-wide responses to abiotic stress through transcriptomic analysis by a high-throughput sequencing platform. We report a comprehensive analysis of transcriptome dynamics, defining profiles of elicited gene regulation responses to abiotic stress-associated hormone Abscisic Acid (ABA), cold, drought, and salt treatments. We identified more than 20,000 genes expressed under each aforementioned stress treatments, of which 9,668 display differential expression in response to stress. The comparison of Physcomitrella patens stress regulated genes with unicellular algae, vascular and flowering plants revealed genomic delineation concomitant with the evolutionary movement to land, including a general gene family complexity and loss of genes associated with different functional groups.

  17. Epidermal stem cells response to radiative genotoxic stress

    Human skin is the first organ exposed to various environmental stresses, which requires the development by skin stem cells of specific mechanisms to protect themselves and to ensure tissue homeostasis. As stem cells are responsible for the maintenance of epidermis during individual lifetime, the preservation of genomic integrity in these cells is essential. My PhD aimed at exploring the mechanisms set up by epidermal stem cells in order to protect themselves from two genotoxic stresses, ionizing radiation (Gamma Rays) and ultraviolet radiation (UVB). To begin my PhD, I have taken part of the demonstration of protective mechanisms used by keratinocyte stem cells after ionizing radiation. It has been shown that these cells are able to rapidly repair most types of radiation-induced DNA damage. Furthermore, we demonstrated that this repair is activated by the fibroblast growth factor 2 (FGF2). In order to know if this protective mechanism is also operating in cutaneous carcinoma stem cells, we investigated the response to gamma Rays of carcinoma stem cells isolated from a human carcinoma cell line. As in normal keratinocyte stem cells, we demonstrated that cancer stem cells could rapidly repair radio-induced DNA damage. Furthermore, fibroblast growth factor 2 also mediates this repair, notably thanks to its nuclear isoforms. The second project of my PhD was to study human epidermal stem cells and progenitors responses to UVB radiation. Once cytometry and irradiation conditions were set up, the toxicity of UVB radiation has been evaluate in the primary cell model. We then characterized UVB photons effects on cell viability, proliferation and repair of DNA damage. This study allowed us to bring out that responses of stem cells and their progeny to UVB are different, notably at the level of part of their repair activity of DNA damage. Moreover, progenitors and stem cells transcriptomic responses after UVB irradiation have been study in order to analyze the global

  18. Hormetic Responses of Lonicera Japonica Thunb. To Cadmium Stress

    Liu, Zhouli; Chen, Wei; He, Xingyuan; Jia, Lian; Yu, Shuai; Zhao, Mingzhu

    2015-01-01

    The hormetic responses of Lonicera japonica Thunb. to cadmium (Cd) stress were investigated in a hydroponic experiment. The present results showed that root length and total biomass dry weight increased in comparison with the control at low concentrations Cd. The height of the plant exposed to 2.5 and 5 mg L-1 Cd increased significantly by 11.9% and 12.8% relative to the control, and with the increase of Cd concentrations in the medium, plant height began to decrease. The responses of photosy...

  19. Longevity and the stress response in Drosophila

    Vermeulen, Corneel J.; Loeschcke, Volker

    2007-01-01

    substances. Do these same changes in patterns of expression have the ability to mitigate ageing and prolong lifespan? It appears that parts of this response indeed are also associated with extended longevity, whereas some elements are not, due to their high cost or long-term deleterious consequences. Here we...... briefly review the state of the art of research on ageing and longevity in the model organism Drosophila, with focus on the role of the general stress response. We will conclude by contemplating some of the implications of the findings in this research and will suggest several directions for future...

  20. A rice stress-responsive NAC gene enhances tolerance of transgenic wheat to drought and salt stresses.

    Saad, Abu Sefyan I; Li, Xu; Li, He-Ping; Huang, Tao; Gao, Chun-Sheng; Guo, Mao-Wei; Cheng, Wei; Zhao, Guang-Yao; Liao, Yu-Cai

    2013-04-01

    Drought and salinity are the primary factors limiting wheat production worldwide. It has been shown that a rice stress-responsive transcription factor encoded by the rice NAC1 gene (SNAC1) plays an important role in drought stress tolerance. Therefore, we introduced the SNAC1 gene under the control of a maize ubiquitin promoter into an elite Chinese wheat variety Yangmai12. Plants expressing SNAC1 displayed significantly enhanced tolerance to drought and salinity in multiple generations, and contained higher levels of water and chlorophyll in their leaves, as compared to wild type. In addition, the fresh and dry weights of the roots of these plants were also increased, and the plants had increased sensitivities to abscisic acid (ABA), which inhibited root and shoot growth. Furthermore, quantitative real-time polymerase chain reactions revealed that the expressions of genes involved in abiotic stress/ABA signaling, such as wheat 1-phosphatidylinositol-3-phosphate-5-kinase, sucrose phosphate synthase, type 2C protein phosphatases and regulatory components of ABA receptor, were effectively regulated by the alien SNAC1 gene. These results indicated high and functional expression of the rice SNAC1 gene in wheat. And our study provided a promising approach to improve the tolerances of wheat cultivars to drought and salinity through genetic engineering. PMID:23415326

  1. Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses

    Su Zhen

    2011-07-01

    Full Text Available Abstract Background Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation. Results A microarray experiment was conducted using root samples collected 6, 24, and 48 h after application of 180 mM NaCl. Analysis of 11 statistically significant expression profiles revealed different behaviors between primary and secondary metabolism pathways in response to external stress. Secondary metabolism that helps to maintain osmotic balance was induced. One of the highly induced transcription factor genes was successfully cloned, and was named MtCBF4. Phylogenetic analysis revealed that MtCBF4, which belongs to the AP2-EREBP transcription factor family, is a novel member of the CBF transcription factor in M. truncatula. MtCBF4 is shown to be a nuclear-localized protein. Expression of MtCBF4 in M. truncatula was induced by most of the abiotic stresses, including salt, drought, cold, and abscisic acid, suggesting crosstalk between these abiotic stresses. Transgenic Arabidopsis over-expressing MtCBF4 enhanced tolerance to drought and salt stress, and activated expression of downstream genes that contain DRE elements. Over-expression of MtCBF4 in M. truncatula also enhanced salt tolerance and induced expression level of corresponding downstream genes. Conclusion Comprehensive transcriptomic analysis revealed complex mechanisms exist in plants in response to salt stress. The novel transcription factor gene MtCBF4 identified here played an important role in response to abiotic stresses, indicating that it might be a good candidate gene for genetic improvement to produce stress-tolerant plants.

  2. Decreased response to social defeat stress in μ-opioid-receptor knockout mice

    Komatsu, Hiroshi; Ohara, Arihisa; Sasaki, Kazumasu; Abe, Hiromi; Hattori, Hisaki; Hall, F Scott; Uhl, George R.; Sora, Ichiro

    2011-01-01

    Substantial evidence exists that opioid systems are involved in stress response and that changes in opioid systems in response to stressors affect both reward and analgesia. Reportedly, mice suffering chronic social defeat stress subsequently show aversion to social contact with unfamiliar mice. To further examine the role of opioid systems in stress response, the behavioral and neurochemical effects of chronic social defeat stress (psychosocial stress) were evaluated in μ-opioid-receptor kno...

  3. A robust and reliable non-invasive test for stress responsivity in mice

    Zimprich, Annemarie; Garrett, Lillian; Deussing, Jan M.; Carsten T. Wotjak; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabě; Wurst, Wolfgang; Hölter, Sabine M.

    2014-01-01

    Stress and an altered stress response have been associated with many multifactorial diseases, such as psychiatric disorders or neurodegenerative diseases. As currently mouse mutants for each single gene are generated and phenotyped in a large-scale manner, it seems advisable also to test these mutants for alterations in their stress responses. Here we present the determinants of a robust and reliable non-invasive test for stress-responsivity in mice. Stress is applied through restraining the ...

  4. Fatty acids and oxidative stress in psychiatric disorders

    Tonello Lucio; Cocchi Massimo; Tsaluchidu Sofia; Puri Basant K

    2008-01-01

    Abstract Background The aim of this study was to determine whether there is published evidence for increased oxidative stress in neuropsychiatric disorders. Methods A PubMed search was carried out using the MeSH search term 'oxidative stress' in conjunction with each of the DSM-IV-TR diagnostic categories of the American Psychiatric Association in order to identify potential studies. Results There was published evidence of increased oxidative stress in the following DSM-IV-TR diagnostic categ...

  5. Proteome analysis of alfalfa roots in response to water deifcit stress

    Rahman Md Atikur; Kim Yong-Goo; AlamIftekhar; LIU Gong-she; Lee Hyoshin; Lee Jeung Joo; Lee Byung-Hyun

    2016-01-01

    To evaluate the response of alfalfa to water deifcit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, folowed by 3 days re-watering. Water deifcit increased H2O2content, lipid peroxidation, DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, and the free proline level in alfalfa roots. Root proteins were extracted and separated by two-dimentional polyacrylamide gel electrophoresis (2-DE). A total of 49 WD-responsive proteins were identiifed in alfalfa roots; 25 proteins were reproducibly found to be up-regulated and 24 were down-regulated. Two proteins, namely cytosolic ascorbate peroxidase (APx2) and putative F-box protein were newly detected on 2-DE maps of WD-treated plants. We identiifed several proteins including agamous-like 65, albumin b-32, inward rectifying potassium channel, and auxin-independent growth promoter. The identiifed proteins are involved in a variety of celular functions including calcium signaling, abacisic acid (ABA) biosynthesis, reactive oxygen species (ROS) regulation, transcription/ translation, antioxidant/detoxiifcation/stress defense, energy metabolism, signal transduction, and storage. These results indicate the potential candidates were responsible for adaptive response in alfalfa roots.

  6. Stresses in sulfuric acid anodized coatings on aluminum

    Alwitt, R. S.; Xu, J.; Mcclung, R. C.

    1993-01-01

    Stresses in porous anodic alumina coatings have been measured for specimens stabilized in air at different temperatures and humidities. In ambient atmosphere the stress is tensile after anodic oxidation and is compressive after sealing. Exposure to dry atmosphere causes the stress to change to strongly tensile, up to 110 MPa. The stress increase is proportional to the loss of water from the coating. These changes are reversible with changes in humidity. Similar reversible effects occur upon moderate temperature changes. The biaxial modulus of the coating is about 100 GPa.

  7. Severe Injury Is Associated With Insulin Resistance, Endoplasmic Reticulum Stress Response, and Unfolded Protein Response

    Jeschke, Marc G.; Finnerty, Celeste C.; Herndon, David N.; Song, Juquan; Boehning, Darren; Tompkins, Ronald G.; Baker, Henry V.; Gauglitz, Gerd G.

    2012-01-01

    Objective We determined whether postburn hyperglycemia and insulin resistance are associated with endoplasmic reticulum (ER) stress/unfolded protein response (UPR) activation leading to impaired insulin receptor signaling. Background Inflammation and cellular stress, hallmarks of severely burned and critically ill patients, have been causally linked to insulin resistance in type 2 diabetes via induction of ER stress and the UPR. Methods Twenty severely burned pediatric patients were compared with 36 nonburned children. Clinical markers, protein, and GeneChip analysis were used to identify transcriptional changes in ER stress and UPR and insulin resistance–related signaling cascades in peripheral blood leukocytes, fat, and muscle at admission and up to 466 days postburn. Results Burn-induced inflammatory and stress responses are accompanied by profound insulin resistance and hyperglycemia. Genomic and protein analysis revealed that burn injury was associated with alterations in the signaling pathways that affect insulin resistance, ER/sarcoplasmic reticulum stress, inflammation, and cell growth/apoptosis up to 466 days postburn. Conclusion Burn-induced insulin resistance is associated with persistent ER/sarcoplasmic reticulum stress/UPR and subsequent suppressed insulin receptor signaling over a prolonged period of time. PMID:22241293

  8. CHEMICAL FLUX IN AN ACID-STRESSED STREAM

    The acidity of rain and snow falling on widely separated areas of the world has been increasing during the past 30 yr (refs 1-3). Acid rainfall consists of a dilute solution of sulphuric and nitric acids due to the oxidation and hydrolysis of airborne sulphur and nitrogen and fre...

  9. Stress -induced biosynthesis of dicaffeoylquinic acids in globe artichoke

    Moglia, A.; Lanteri, S.; Comino, C.; Acquadro, A.; Vos, de C.H.; Beekwilder, M.J.

    2008-01-01

    Leaf extracts from globe artichoke (Cynara cardunculus L. var. scolymus) have been widely used in medicine as hepatoprotectant and choleretic agents. Globe artichoke leaves represent a natural source of phenolic acids with dicaffeoylquinic acids, such as cynarin (1,3-dicaffeoylquinic acid), along wi

  10. Application of electrochemical optical waveguide lightmode spectroscopy for studying the effect of different stress factors on lactic acid bacteria

    Electrochemical optical waveguide lightmode spectroscopy (EC-OWLS) has been developed to combine evanescent-field optical sensing with electrochemical control of surface adsorption processes. For bioanalytical sensing, a layer of indium tin oxide (ITO) served as both a high-refractive index waveguide and a conductive electrode. In addition, an electrochemical flow-through fluid cuvette was applied, which incorporated working, reference, and counter electrodes, and was compatible with the constraints of optical sensing. The subject of our study was to monitor how the different stress factors (lactic acid, acetic acid and hydrogen peroxide) influence the survival of lactic acid bacteria. The advantage of EC-OWLS technique is that we could carry out kinetic studies on the behaviour of bacteria under stress conditions, and after exposure of lactobacilli to acid and oxidative stress we get faster results about the status of bacteria compared to the traditional quantitative methods. After optimization of the polarization potential used, calibration curve was determined and the sensor response of different rate of living and damaged cells was studied. The bacterial cells were adsorbed in native form on the surface of the sensor by ensuring polarizing potential (1 V) and were exposed to different concentration of acetic acid and hydrogen peroxide solution to 1 h, respectively and the behaviour of bacteria was monitored. Results were compared to traditional micro-assay method

  11. Reconstructing a Network of Stress-Response Regulators via Dynamic System Modeling of Gene Regulation

    Wei-Sheng Wu

    2008-01-01

    Full Text Available Unicellular organisms such as yeasts have evolved mechanisms to respond to environmental stresses by rapidly reorganizing the gene expression program. Although many stress-response genes in yeast have been discovered by DNA microarrays, the stress-response transcription factors (TFs that regulate these stress-response genes remain to be investigated. In this study, we use a dynamic system model of gene regulation to describe the mechanism of how TFs may control a gene’s expression. Then, based on the dynamic system model, we develop the Stress Regulator Identification Algorithm (SRIA to identify stress-response TFs for six kinds of stresses. We identified some general stress-response TFs that respond to various stresses and some specific stress-response TFs that respond to one specifi c stress. The biological significance of our findings is validated by the literature. We found that a small number of TFs is probably suffi cient to control a wide variety of expression patterns in yeast under different stresses. Two implications can be inferred from this observation. First, the response mechanisms to different stresses may have a bow-tie structure. Second, there may be regulatory cross-talks among different stress responses. In conclusion, this study proposes a network of stress-response regulators and the details of their actions.

  12. Perfluorooctanoic Acid Exposure Suppresses T-independent Antibody Responses

    Exposure to  3.75mg/kg of perfluoroocatnoic acid (PFOA) for 15d suppresses T-dependent antibody responses (TDAR), suggesting that T helper cells and/or B cells/plasma cells may be impacted. This study evaluated effects of PFOA exposure on the T cell-independent antibody response...

  13. Multifaceted roles of aquaporins as molecular conduits in plant responses to abiotic stresses.

    Srivastava, Ashish Kumar; Penna, Suprasanna; Nguyen, Dong Van; Tran, Lam-Son Phan

    2016-06-01

    Abiotic stress has become a challenge to food security due to occurrences of climate change and environmental degradation. Plants initiate molecular, cellular and physiological changes to respond and adapt to various types of abiotic stress. Understanding of plant response mechanisms will aid in strategies aimed at improving stress tolerance in crop plants. One of the most common and early symptoms associated with these stresses is the disturbance in plant-water homeostasis, which is regulated by a group of proteins called "aquaporins". Aquaporins constitute a small family of proteins which are classified further on the basis of their localization, such as plasma membrane intrinsic proteins, tonoplast intrinsic proteins, nodulin26-like intrinsic proteins (initially identified in symbiosomes of legumes but also found in the plasma membrane and endoplasmic reticulum), small basic intrinsic proteins localized in ER (endoplasmic reticulum) and X intrinsic proteins present in plasma membrane. Apart from water, aquaporins are also known to transport CO2, H2O2, urea, ammonia, silicic acid, arsenite and wide range of small uncharged solutes. Besides, aquaporins also function to modulate abiotic stress-induced signaling. Such kind of versatile functions has made aquaporins a suitable candidate for development of transgenic plants with increased tolerance toward different abiotic stress. Toward this endeavor, the present review describes the versatile functions of aquaporins in water uptake, nutrient balancing, long-distance signal transfer, nutrient/heavy metal acquisition and seed development. Various functional genomic studies showing the potential of specific aquaporin isoforms for enhancing plant abiotic stress tolerance are summarized and future research directions are given to design stress-tolerant crops. PMID:25430890

  14. Scolopendin 2 leads to cellular stress response in Candida albicans.

    Lee, Heejeong; Hwang, Jae-Sam; Lee, Dong Gun

    2016-07-01

    Centipedes, a kind of arthropod, have been reported to produce antimicrobial peptides as part of an innate immune response. Scolopendin 2 (AGLQFPVGRIGRLLRK) is a novel antimicrobial peptide derived from the body of the centipede Scolopendra subspinipes mutilans by using RNA sequencing. To investigate the intracellular responses induced by scolopendin 2, reactive oxygen species (ROS) and glutathione accumulation and lipid peroxidation were monitored over sublethal and lethal doses. Intracellular ROS and antioxidant molecule levels were elevated and lipids were peroxidized at sublethal concentrations. Moreover, the Ca(2+) released from the endoplasmic reticulum accumulated in the cytosol and mitochondria. These stress responses were considered to be associated with yeast apoptosis. Candida albicans cells exposed to scolopendin 2 were identified using diagnostic markers of apoptotic response. Various responses such as phosphatidylserine externalization, chromatin condensation, and nuclear fragmentation were exhibited. Scolopendin 2 disrupted the mitochondrial membrane potential and activated metacaspase, which was mediated by cytochrome c release. In conclusion, treatment of C. albicans with scolopendin 2 induced the apoptotic response at sublethal doses, which in turn led to mitochondrial dysfunction, metacaspase activation, and cell death. The cationic antimicrobial peptide scolopendin 2 from the centipede is a potential antifungal peptide, triggering the apoptotic response. PMID:27207682

  15. Mitochondrial Composition,Function and Stress Response in Plants

    Richard P.Jacoby; Lei Li; Shaobai Huang; Chun Pong Lee; A.Harvey Millar; Nicolas L.Taylor

    2012-01-01

    The primary function of mitochondria is respiration,where catabolism of substrates is coupled to ATP synthesis via oxidative phosphorylation.In plants,mitochondrial composition is relatively complex and flexible and has specific pathways to support photosynthetic processes in illuminated leaves.This review begins with outlining current models of mitochondrial composition in plant cells,with an emphasis upon the assembly of the complexes of the classical electron transport chain (ETC).Next,we focus upon the comparative analysis of mitochondrial function from different tissue types.A prominent theme in the plant mitochondrial literature involves linking mitochondrial composition to environmental stress responses,and this review then gives a detailed outline of how oxidative stress impacts upon the plant mitochondrial proteome with particular attention to the role of transition metals.This is followed by an analysis of the signaling capacity of mitochondrial reactive oxygen species,which studies the transcriptional changes of stress responsive genes as a framework to define specific signals emanating from the mitochondrion.Finally,specific mitochondrial roles during exposure to harsh environments are outlined,with attention paid to mitochondrial delivery of energy and intermediates,mitochondrial support for photosynthesis,and mitochondrial processes operating within root cells that mediate tolerance to anoxia and unfavorable soil chemistries.

  16. Mcm2 phosphorylation and the response to replicative stress

    Stead Brent E

    2012-05-01

    Full Text Available Abstract Background The replicative helicase in eukaryotic cells is comprised of minichromosome maintenance (Mcm proteins 2 through 7 (Mcm2-7 and is a key target for regulation of cell proliferation. In addition, it is regulated in response to replicative stress. One of the protein kinases that targets Mcm2-7 is the Dbf4-dependent kinase Cdc7 (DDK. In a previous study, we showed that alanine mutations of the DDK phosphorylation sites at S164 and S170 in Saccharomyces cerevisiae Mcm2 result in sensitivity to caffeine and methyl methanesulfonate (MMS leading us to suggest that DDK phosphorylation of Mcm2 is required in response to replicative stress. Results We show here that a strain with the mcm2 allele lacking DDK phosphorylation sites (mcm2AA is also sensitive to the ribonucleotide reductase inhibitor, hydroxyurea (HU and to the base analogue 5-fluorouracil (5-FU but not the radiomimetic drug, phleomycin. We screened the budding yeast non-essential deletion collection for synthetic lethal interactions with mcm2AA and isolated deletions that include genes involved in the control of genome integrity and oxidative stress. In addition, the spontaneous mutation rate, as measured by mutations in CAN1, was increased in the mcm2AA strain compared to wild type, whereas with a phosphomimetic allele (mcm2EE the mutation rate was decreased. These results led to the idea that the mcm2AA strain is unable to respond properly to DNA damage. We examined this by screening the deletion collection for suppressors of the caffeine sensitivity of mcm2AA. Deletions that decrease spontaneous DNA damage, increase homologous recombination or slow replication forks were isolated. Many of the suppressors of caffeine sensitivity suppressed other phenotypes of mcm2AA including sensitivity to genotoxic drugs, the increased frequency of cells with RPA foci and the increased mutation rate. Conclusions Together these observations point to a role for DDK-mediated phosphorylation

  17. Investigating the drought-stress response of hybrid poplar genotypes by metabolite profiling.

    Barchet, Genoa L H; Dauwe, Rebecca; Guy, Robert D; Schroeder, William R; Soolanayakanahally, Raju Y; Campbell, Malcolm M; Mansfield, Shawn D

    2014-11-01

    Drought stress is perhaps the most commonly encountered abiotic stress plants experience in the natural environment, and it is one of the most important factors limiting plant productivity. Here, we employed untargeted metabolite profiling to examine four drought-stressed hybrid poplar (Populus spp.) genotypes for their metabolite content, using gas chromatography coupled to mass spectrometry. The primary objective of these analyses was to characterize the metabolite profile of poplar trees to assess relative drought resistance and to investigate the underlying biochemical mechanisms employed by the genotypes to combat drought. Metabolite profiling identified key metabolites that increased or decreased in relative abundance upon exposure to drought stress. Overall, amino acids, the antioxidant phenolic compounds catechin and kaempferol, as well as the osmolytes raffinose and galactinol exhibited increased abundance under drought stress, whereas metabolites involved in photorespiration, redox regulation and carbon fixation showed decreased abundance under drought stress. One clone in particular, Okanese, displayed unique responses to the imposed drought conditions. This clone was found to have higher leaf water potential, but lower growth rate relative to the other clones tested. Okanese also had lower accumulation of osmolytes such as raffinose, galactinol and proline, but higher overall levels of antioxidants such as catechin and dehydroascorbic acid. As such, it was proposed that osmotic adjustment as a mechanism for drought avoidance in this clone is not as well developed in comparison with the other clones investigated in this study, and that a possible alternative mechanism for the enhanced drought avoidance displayed by Okanese may be due to differential allocation of resources or better retention of water. PMID:24178982

  18. Plant natriuretic peptides are apoplastic and paracrine stress response molecules

    Wang, Yuhua

    2011-04-07

    Higher plants contain biologically active proteins that are recognized by antibodies against human atrial natriuretic peptide (ANP). We identified and isolated two Arabidopsis thaliana immunoreactive plant natriuretic peptide (PNP)-encoding genes, AtPNP-A and AtPNP-B, which are distantly related members of the expansin superfamily and have a role in the regulation of homeostasis in abiotic and biotic stresses, and have shown that AtPNP-A modulates the effects of ABA on stomata. Arabidopsis PNP (PNP-A) is mainly expressed in leaf mesophyll cells, and in protoplast assays we demonstrate that it is secreted using AtPNP-A:green fluorescent protein (GFP) reporter constructs and flow cytometry. Transient reporter assays provide evidence that AtPNP-A expression is enhanced by heat, osmotica and salt, and that AtPNP-A itself can enhance its own expression, thereby generating a response signature diagnostic for paracrine action and potentially also autocrine effects. Expression of native AtPNP-A is enhanced by osmotica and transiently by salt. Although AtPNP-A expression is induced by salt and osmotica, ABA does not significantly modulate AtPNP-A levels nor does recombinant AtPNP-A affect reporter expression of the ABA-responsive RD29A gene. Together, these results provide experimental evidence that AtPNP-A is stress responsive, secreted into the apoplastic space and can enhance its own expression. Furthermore, our findings support the idea that AtPNP-A, together with ABA, is an important component in complex plant stress responses and that, much like in animals, peptide signaling molecules can create diverse and modular signals essential for growth, development and defense under rapidly changing environmental conditions. © 2011 The Author.

  19. Adventitious rooting in cuttings of croton and hibiscus in response to indolbutyric acid and humic acid

    Lílian Estrela Borges Baldotto; Marihus Altoé Baldotto; Raíssa Rezende Soares; Herminia Emilia Prieto Martinez; Vitor Hugo Alvarez Venegas

    2012-01-01

    Adventitious rooting of ornamental plants can be accelerated by the application of growth regulators, such as auxin. Humic acids, organic matter in soil and organic compounds also have a biostimulant effect. This work evaluated the rooting in cuttings of croton (Codianeum variegatum L. Rumph) and hibiscus (Hibiscus rosa-sinensis L) in response to the application of different concentrations of indolbutyric acid (IBA) and humic acid (HA). The experiment was carried out in a greenhouse. Apical s...

  20. Effect of Salicylic Acid and Ascorbic Acid on Germination Indexes and Enzyme Activity of Sorghum Seeds under Drought Stress

    Tabatabaei S. A.

    2013-11-01

    Full Text Available Seed priming methods have been used to increase germination characteristics under stress conditions. The effects of drought stress (0, -4, -8, -12 and -16 bar and salicylic acid 25 ppm at 15 °C for 15 h and ascorbic acid 25 ppm at 15 °C for 15 h on germination percentage, germination index, means time to germination, normal seedling percentage and enzyme activity were assessed in the laboratory for sorghum seeds (Sorghum bicolor L.. Results showed that the highest germination percentage (83.33%, normal seedling percentage (69.67%, germination index (25.29 and the minimum means time to germination (2.87 were attained from priming with salicylic acid in control conditions. Therefore, seed priming significantly (p≤ 0.01 increased germination characteristics as compared to the unprimed under drought stress. Also, priming increased catalase and ascorbate peroxidase as compared to the unprimed seeds.

  1. Molecular mechanism of dehydrin in response to environmental stress in plant

    ZHANG Yuxiu; WANG Zi; XU Jin

    2007-01-01

    Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilic a-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration,and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

  2. Cellular response to substrate rigidity is governed by either stress or strain.

    Yip, Ai Kia; Iwasaki, Katsuhiko; Ursekar, Chaitanya; Machiyama, Hiroaki; Saxena, Mayur; Chen, Huiling; Harada, Ichiro; Chiam, Keng-Hwee; Sawada, Yasuhiro

    2013-01-01

    Cells sense the rigidity of their substrate; however, little is known about the physical variables that determine their response to this rigidity. Here, we report traction stress measurements carried out using fibroblasts on polyacrylamide gels with Young's moduli ranging from 6 to 110 kPa. We prepared the substrates by employing a modified method that involves N-acryloyl-6-aminocaproic acid (ACA). ACA allows for covalent binding between proteins and elastomers and thus introduces a more stable immobilization of collagen onto the substrate when compared to the conventional method of using sulfo-succinimidyl-6-(4-azido-2-nitrophenyl-amino) hexanoate (sulfo-SANPAH). Cells remove extracellular matrix proteins off the surface of gels coated using sulfo-SANPAH, which corresponds to lower values of traction stress and substrate deformation compared to gels coated using ACA. On soft ACA gels (Young's modulus 20 kPa), traction stress plateaus at a limiting value and the substrate deformation decreases with increasing substrate rigidity. Sustained substrate strain on soft substrates and sustained traction stress on stiff substrates suggest these may be factors governing cellular responses to substrate rigidity. PMID:23332055

  3. A tension stress loading unit designed for characterizing indentation response of single crystal silicon under tension stress

    Huang, Hu; Zhao, Hongwei; Shi, Chengli; Hu, Xiaoli; Cui, Tao; Tian, Ye

    2013-09-01

    In this paper, a tension stress loading unit is designed to provide tension stress for brittle materials by combining the piezo actuator and the flexible hinge. The structure of the tension stress loading unit is analyzed and discussed via the theoretical method and finite element simulations. Effects of holding time, the installed specimen and hysteresis of the piezo actuator on output performances of the tension stress loading unit are studied in detail. An experiment system is established by combing the indentation testing unit and the developed tension stress loading unit to characterize indentation response of single crystal silicon under tension stress. Experiment results indicate that tension stress leads to increasing of indentation displacement for the same inden-tation load of single crystal silicon. This paper provides a new tool for studying indentation response of brittle materials under tension stress.

  4. Adrenal cortical response to stress at Three Mile Island

    The present study examined the relationship between biochemical, psychologic, and behavioral components of chronic stress associated with living near the damaged nuclear power plant at Three Mile Island (TMI). Relative to control subjects, TMI subjects had higher levels of urinary cortisol, which correlated significantly with urinary catecholamines, self-report of physical and mental symptoms, and decrements in task performance. Further, it was found that males had higher urinary cortisol levels than females at TMI, while at the control sites, levels of cortisol were comparable between males and females. Finally, no significant relationship between coping style and urinary cortisol was detected. Levels of stress response among TMI are residents, though significantly greater than control subjects, were within normal ranges and thus should be considered subclinical in intensity. Their persistence over 17 months, however, suggests some cause for concern

  5. Sch9 regulates intracellular protein ubiquitination by controlling stress responses

    Beibei Qie

    2015-08-01

    Full Text Available Protein ubiquitination and the subsequent degradation are important means by which aberrant proteins are removed from cells, a key requirement for long-term survival. In this study, we found that the overall level of ubiquitinated proteins dramatically decreased as yeast cell grew from log to stationary phase. Deletion of SCH9, a gene encoding a key protein kinase for longevity control, decreased the level of ubiquitinated proteins in log phase and this effect could be reversed by restoring Sch9 function. We demonstrate here that the decrease of ubiquitinated proteins in sch9Δ cells in log phase is not caused by changes in ubiquitin expression, proteasome activity, or autophagy, but by enhanced expression of stress response factors and a decreased level of oxidative stress. Our results revealed for the first time how Sch9 regulates the level of ubiquitinated proteins and provides new insight into how Sch9 controls longevity.

  6. Microtubules self-repair in response to mechanical stress

    Schaedel, Laura; John, Karin; Gaillard, Jérémie; Nachury, Maxence V.; Blanchoin, Laurent; Théry, Manuel

    2015-11-01

    Microtubules--which define the shape of axons, cilia and flagella, and provide tracks for intracellular transport--can be highly bent by intracellular forces, and microtubule structure and stiffness are thought to be affected by physical constraints. Yet how microtubules tolerate the vast forces exerted on them remains unknown. Here, by using a microfluidic device, we show that microtubule stiffness decreases incrementally with each cycle of bending and release. Similar to other cases of material fatigue, the concentration of mechanical stresses on pre-existing defects in the microtubule lattice is responsible for the generation of more extensive damage, which further decreases microtubule stiffness. Strikingly, damaged microtubules were able to incorporate new tubulin dimers into their lattice and recover their initial stiffness. Our findings demonstrate that microtubules are ductile materials with self-healing properties, that their dynamics does not exclusively occur at their ends, and that their lattice plasticity enables the microtubules' adaptation to mechanical stresses.

  7. The behavioral and endocrinological development of stress response in dogs.

    Nagasawa, Miho; Shibata, Yoh; Yonezawa, Akiko; Morita, Tomoko; Kanai, Masanori; Mogi, Kazutaka; Kikusui, Takefumi

    2014-05-01

    Endocrinological stress response has been shown to be absent in a specific period of the early life of rodents; this is named the stress-hyporesponsive period (SHRP). The SHRP is a significant period for the appropriate development of infants. In this study, the presence of SHRP in dogs was identified by conducting a 5-min separation test in 142 Labrador retriever puppies in their early socialization period and measuring the changes in urinary cortisol levels. An increase in cortisol after separation was found after 5 weeks of age, suggesting that the SHRP persists until 4 weeks of age in dogs. The distress vocalization during separation changed and the lactating behavior decreased rapidly around 5 weeks of age, suggesting that the endocrinological and emotional aspects of development change at approximately 5 weeks of age and maternal inhibition of cortisol might occur in dogs as well as rodents. PMID:24019027

  8. Metabolic and Phenotypic Responses of Greenhouse-Grown Maize Hybrids to Experimentally Controlled Drought Stress

    Sandra Witt; Luis Galici; Jan Lisec; Jill Cairns; Axel Tiessen; Jose Luis Araus; Natalia Palacios-Rojas; Alisdair R.Fernie

    2012-01-01

    Adaptation to abiotic stresses like drought is an important acquirement of agriculturally relevant crops like maize.Development of enhanced drought tolerance in crops grown in climatic zones where drought is a very dominant stress factor therefore plays an essential role in plant breeding.Previous studies demonstrated that corn yield potential and enhanced stress tolerance are associated traits.In this study,we analyzed six different maize hybrids for their ability to deal with drought stress in a greenhouse experiment.We were able to combine data from morphophysiological parameters measured under well-watered conditions and under water restriction with metabolic data from different organs.These different organs possessed distinct metabolite compositions,with the leaf blade displaying the most considerable metabolome changes following water deficiency.Whilst we could show a general increase in metabolite levels under drought stress,including changes in amino acids,sugars,sugar alcohols,and intermediates of the TCA cycle,these changes were not differential between maize hybrids that had previously been designated based on field trial data as either drought-tolerant or susceptible.The fact that data described here resulted from a greenhouse experiment with rather different growth conditions compared to natural ones in the field may explain why tolerance groups could not be confirmed in this study.We were,however,able to highlight several metabolites that displayed conserved responses to drought as well as metabolites whose levels correlated well with certain physiological traits.

  9. Arabidopsis decuple mutant reveals the importance of SnRK2 kinases in osmotic stress responses in vivo

    Fujii, Hiroaki

    2011-01-10

    Osmotic stress associated with drought or salinity is a major factor that limits plant productivity. Protein kinases in the SNF1-related protein kinase 2 (SnRK2) family are activated by osmotic stress, suggesting that the kinases are involved in osmotic stress signaling. However, due to functional redundancy, their contribution to osmotic stress responses remained unclear. In this report, we constructed an Arabidopsis line carrying mutations in all 10 members of the SnRK2 family. The decuple mutant snrk2.1/2/3/4/5/6/7/8/9/10 grew poorly under hyperosmotic stress conditions but was similar to the wild type in culture media in the absence of osmotic stress. The mutant was also defective in gene regulation and the accumulation of abscisic acid (ABA), proline, and inositol 1,4,5-trisphosphate under osmotic stress. In addition, analysis of mutants defective in the ABA-activated SnRK2s (snrk2.2/3/6) and mutants defective in the rest of the SnRK2s (snrk2.1/4/5/7/8/9/10) revealed that SnRK2s are a merging point of ABA-dependent and -independent pathways for osmotic stress responses. These results demonstrate critical functions of the SnRK2s in mediating osmotic stress signaling and tolerance.

  10. Global Expressions Landscape of NAC Transcription Factor Family and Their Responses to Abiotic Stresses in Citrullus lanatus

    Lv, Xiaolong; Lan, Shanrong; Guy, Kateta Malangisha; Yang, Jinghua; Zhang, Mingfang; Hu, Zhongyuan

    2016-01-01

    Watermelon (Citrullus lanatus) is one xerophyte that has relative higher tolerance to drought and salt stresses as well as more sensitivity to cold stress, compared with most model plants. These characteristics facilitate it a potential model crop for researches on salt, drought or cold tolerance. In this study, a genome-wide comprehensive analysis of the ClNAC transcription factor (TF) family was carried out for the first time, to investigate their transcriptional profiles and potential functions in response to these abiotic stresses. The expression profiling analysis reveals that several NAC TFs are highly responsive to abiotic stresses and development, for instance, subfamily IV NACs may play roles in maintaining water status under drought or salt conditions, as well as water and metabolites conduction and translocation toward fruit. In contrast, rapid and negative responses of most of the ClNACs to low-temperature adversity may be related to the sensitivity to cold stress. Crosstalks among these abiotic stresses and hormone (abscisic acid and jasmonic acid) pathways were also discussed based on the expression of ClNAC genes. Our results will provide useful insights for the functional mining of NAC family in watermelon, as well as into the mechanisms underlying abiotic tolerance in other cash crops. PMID:27491393

  11. Genomic counter-stress changes induced by the relaxation response.

    Jeffery A Dusek

    Full Text Available BACKGROUND: Mind-body practices that elicit the relaxation response (RR have been used worldwide for millennia to prevent and treat disease. The RR is characterized by decreased oxygen consumption, increased exhaled nitric oxide, and reduced psychological distress. It is believed to be the counterpart of the stress response that exhibits a distinct pattern of physiology and transcriptional profile. We hypothesized that RR elicitation results in characteristic gene expression changes that can be used to measure physiological responses elicited by the RR in an unbiased fashion. METHODS/PRINCIPAL FINDINGS: We assessed whole blood transcriptional profiles in 19 healthy, long-term practitioners of daily RR practice (group M, 19 healthy controls (group N(1, and 20 N(1 individuals who completed 8 weeks of RR training (group N(2. 2209 genes were differentially expressed in group M relative to group N(1 (p<0.05 and 1561 genes in group N(2 compared to group N(1 (p<0.05. Importantly, 433 (p<10(-10 of 2209 and 1561 differentially expressed genes were shared among long-term (M and short-term practitioners (N(2. Gene ontology and gene set enrichment analyses revealed significant alterations in cellular metabolism, oxidative phosphorylation, generation of reactive oxygen species and response to oxidative stress in long-term and short-term practitioners of daily RR practice that may counteract cellular damage related to chronic psychological stress. A significant number of genes and pathways were confirmed in an independent validation set containing 5 N(1 controls, 5 N(2 short-term and 6 M long-term practitioners. CONCLUSIONS/SIGNIFICANCE: This study provides the first compelling evidence that the RR elicits specific gene expression changes in short-term and long-term practitioners. Our results suggest consistent and constitutive changes in gene expression resulting from RR may relate to long term physiological effects. Our study may stimulate new

  12. Neonatal stress tempers vulnerability of acute stress response in adult socially isolated rats

    Mariangela Serra

    2014-06-01

    Full Text Available Adverse experiences occurred in early life and especially during childhood and adolescence can have negative impact on behavior later in life and the quality of maternal care is considered a critical moment that can considerably influence the development and the stress responsiveness in offspring. This review will assess how the association between neonatal and adolescence stressful experiences such as maternal separation and social isolation, at weaning, may influence the stress responsiveness and brain plasticity in adult rats. Three hours of separation from the pups (3-14 postnatal days significantly increased frequencies of maternal arched-back nursing and licking-grooming by dams across the first 14 days postpartum and induced a long-lasting increase in their blood levels of corticosterone. Maternal separation, which per sedid not modified brain and plasma allopregnanolone and corticosterone levels in adult rats, significantly reduced social isolation-induced decrease of the levels of these hormones. Moreover, the enhancement of corticosterone and allopregnanolone levels induced by foot shock stress in socially isolated animals that were exposed to maternal separation was markedly reduced respect to that observed in socially isolated animals. Our results suggest that in rats a daily brief separation from the mother during the first weeks of life, which per se did not substantially alter adult function and reactivity of hypothalamic-pituitary-adrenal (HPA axis, elicited a significant protection versus the subsequent long-term stressful experience such that induced by social isolation from weaning. Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in NeonatologyGuest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou

  13. Transactional Associations Between Youths’ Responses to Peer Stress and Depression: The Moderating Roles of Sex and Stress Exposure

    Agoston, Anna Monica; Rudolph, Karen D.

    2011-01-01

    This study examined transactional associations between responses to peer stress and depression in youth. Specifically, it tested the hypotheses that (a) depression would predict fewer effortful responses and more involuntary, dysregulated responses to peer stress over time; and (b) fewer adaptive and more maladaptive responses would predict subsequent depression. Youth (M age = 12.41; SD = 1.19; 86 girls, 81 boys) and their maternal caregivers completed semi-structured interviews and question...

  14. Salicylic acid induced physiological and biochemical changes in wheat under drought stress conditions

    Experiment for finding the effect of pre-soaking of wheat seeds varieties, viz Wafaq-2001 and Punjab-96, in salicylic acid (SA) solution on the drought tolerance of wheat, revealed increase in the total biomass and grain yield per plant as well as in spikes per plant, 100 seed weight, proline, total soluble sugars, membrane stability index (MSI), superoxide dismutase (SOD) and ascorbate peroxidase (APOX) activity in both the tested varieties. The yield increase in drought tolerant variety Wafaq-2001 was more as compared to drought sensitive Punjab-96. Results signify the role of SA in regulating the drought response of wheat and that SA could be seed primed and used as a potential growth regulator under drought stress conditions. (author)

  15. Photosynthetic and growth responses of Schima superba seedlings to sulfuric and nitric acid depositions.

    Yao, Fang-Fang; Ding, Hui-Ming; Feng, Li-Li; Chen, Jing-Jing; Yang, Song-Yu; Wang, Xi-Hua

    2016-05-01

    A continuing rise in acid deposition can cause forest degradation. In China, acid deposition has converted gradually from sulfuric acid deposition (SAD) to nitric acid deposition (NAD). However, the differing responses of photosynthesis and growth to depositions of sulfuric vs. nitric acid have not been well studied. In this study, 1-year-old seedlings of Schima superba, a dominant species in subtropical forests, were treated with two types of acid deposition SO4 (2-)/NO3 (-) ratios (8:1 and 0.7:1) with two applications (foliar spraying and soil drenching) at two pH levels (pH 3.5 and pH 2.5) over a period of 18 months. The results showed that the intensity, acid deposition type, and spraying method had significant effects on the physiological characteristics and growth performance of seedlings. Acid deposition at pH 2.5 via foliar application reduced photosynthesis and growth of S. superba, especially in the first year. Unlike SAD, NAD with high acidity potentially alleviated the negative effects of acidity on physiological properties and growth, probably due to a fertilization effect that improved foliar nitrogen and chlorophyll contents. Our results suggest that trees were damaged mainly by direct acid stress in the short term, whereas in the long term, soil acidification was also likely to be a major risk to forest ecosystems. Our data suggest that the shift in acid deposition type may complicate the ongoing challenge of anthropogenic acid deposition to ecosystem stability. PMID:26797956

  16. Quantification of Abscisic Acid, Cytokinin, and Auxin Content in Salt-Stressed Plant Tissues

    Dobrev, P.; Vaňková, R. (Radomíra)

    2012-01-01

    Plant hormones cytokinins, auxin (indole-3-acetic acid), and abscisic acid are central to regulation of plant growth and defence to abiotic stresses such as salinity. Quantification of the hormone levels and determination of their ratios can reveal different plant strategies to cope with the stress, e.g., suppression of growth or mobilization of plant metabolism. This chapter describes a procedure enabling such quantification. Due to the high variability of these hormones in plant tissues, it...

  17. Low ascorbic acid and increased oxidative stress in gulo−/− mice during development

    Harrison, Fiona E.; Meredith, M. Elizabeth; Dawes, Sean M.; Saskowski, Jeanette L.; May, James M.

    2010-01-01

    Vitamin C (ascorbic acid, AA) depletion during pre-natal and post-natal development can lead to oxidative stress in the developing brains and other organs. Such damage may lead to irreversible effects on later brain function. We studied the relationship between AA deficiency and oxidative stress during development in gulonolactone oxidase (gulo) knockout mice that are unable to synthesize their own ascorbic acid. Heterozygous gulo(+/−) mice can synthesize AA and typically have similar tissue ...

  18. Mycothiol peroxidase MPx protects Corynebacterium glutamicum against acid stress by scavenging ROS

    Tietao Wang; Fen Gao; Yiwen Kang; Chao Zhao; Muhang Li; Xihui Shen; Tao Su; Meiru Si

    2015-01-01

    Corynebacterium glutamicum mycothiol peroxidase (MPx) is a novel CysGPx family peroxidase that uses both the mycoredoxin and thioredoxin reducing systems as proton donors for peroxide detoxification. In this study, we revealed that MPx is also important for cellular survival under acid stress. A Δmpx mutant exhibited significantly decreased resistance to acid stress and markedly increased accumulation of reactive oxygen species (ROS) and protein carbonylation levels in vivo. Overexpression of...

  19. The effects of dietary long-chain essential fatty acids on growth and stress tolerance in pikeperch larvae (Sander lucioperca L.)

    Lund, Ivar; Steenfeldt, Svend Jørgen

    2011-01-01

    The nutritional requirements of pikeperch larvae have been sparsely examined. Dietary polyunsaturated fatty acids, arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may affect growth and physiological stress response in marine fish larvae, but these mechanisms have...... than in the remaining treatments while tissue cortisol contents in these fish seemed lower. The findings of a lower stress response in larvae fed POO may be related to the lower tissue content in these larvae of essential fatty acids especially DHA but also EPA and ARA....... not received as much attention in freshwater fish. Pikeperch larvae were reared on Artemia from day 3 until 21 days posthatch. Artemia were enriched with six formulated emulsions, with inclusion of either fish oil, pure olive oil (POO) or olive oil supplemented with various combinations of ARA, EPA...

  20. Conditioned stress prevents cue-primed cocaine reinstatement only in stress-responsive rats.

    Hadad, Natalie A; Wu, Lizhen; Hiller, Helmut; Krause, Eric G; Schwendt, Marek; Knackstedt, Lori A

    2016-07-01

    Neurobiological mechanisms underlying comorbid posttraumatic stress disorder (PTSD) and cocaine use disorder (CUD) are unknown. We aimed to develop an animal model of PTSD + CUD to examine the neurobiology underlying cocaine-seeking in the presence of PTSD comorbidity. Rats were exposed to cat urine once for 10-minutes and tested for anxiety-like behaviors one week later. Subsequently, rats underwent long-access (LgA) cocaine self-administration and extinction training. Rats were re-exposed to the trauma context and then immediately tested for cue-primed reinstatement of cocaine-seeking. Plasma and brains were collected afterwards for corticosterone assays and real-time qPCR analysis. Urine-exposed (UE; n = 23) and controls not exposed to urine (Ctrl; n = 11) did not differ in elevated plus maze behavior, but UE rats displayed significantly reduced habituation of the acoustic startle response (ASR) relative to Ctrl rats. A median split of ASR habituation scores was used to classify stress-responsive rats. UE rats (n = 10) self-administered more cocaine on Day 1 of LgA than control rats (Ctrl + Coc; n = 8). Re-exposure to the trauma context prevented cocaine reinstatement only in stress-responsive rats. Ctrl + Coc rats had lower plasma corticosterone concentrations than Ctrls, and decreased gene expression of corticotropin releasing hormone (CRH) and Glcci1 in the hippocampus. Rats that self-administered cocaine displayed greater CRH expression in the amygdala that was independent of urine exposure. While we did not find that cat urine exposure induced a PTSD-like phenotype in our rats, the present study underscores the need to separate stressed rats into cohorts based on anxiety-like behavior in order to study individual vulnerability to PTSD + CUD. PMID:27181613

  1. Sense of responsibility in health workers source of job stress

    Nedić Olesja

    2002-01-01

    Full Text Available Job stress is a great problem in developed countries of the world, but in Yugoslavia, it is increased due to additional reasons associated with economic crisis in the society. Health services and health workers are in particulary difficult conditions. The aim of this paper was to examine sources and causes of job stress in health workers. Material and methods The research was undertaken among health workers treated at Health Centre "Hospital" in Novi Sad. The study group included health workers - doctors nurses and laboratory workers, and the control group included the rest of non-medical staff. Adapted Siegrist questionnaire was used. Three factors were examined: extrinsic efforts (disturbances at work, sense of great job responsibility and the need for overtime work; intrinsic efforts (major criticism, thinking about the job from the early morning, getting nervous because of minor problems, discontentment because of unsolved problems at work, relaxation at home and so on, and low reward (respect from the superiors and colleagues, support and security at workplace. Answers were scored indicating intensity (high, moderate, low, not at alt. Statistic analysis included testing the level of significance in health workers in relation to non-medical staff (t test and Fisher's exact test. Results Applying the scoring system it has been established that health workers are exposed to greater job stress, great sense of very high job responsibility and frequent overtime work (p<0,001 than the control group. In regard to answers from the second group - intrinsic effort and low reward, there was no statistical significance between the study and control group. Generally high level of risk factors was established, especially presence of one or more risk factors. Discussion Job stress increases absenteeism, reduces work productivity, causes higher expenses of medical treatment, rehabilitation and staff retraining. It is of great importance to identify factors

  2. Oxidative and nitrosative stress in trichloroethene-mediated autoimmune response

    Reactive oxygen and nitrogen species (RONS) are implicated in the pathogenesis of several autoimmune diseases. Also, increased lipid peroxidation and protein nitration are reported in systemic autoimmune diseases. Lipid peroxidation-derived aldehydes (LPDAs) such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are highly reactive and bind proteins covalently, but their potential to elicit an autoimmune response and contribution to disease pathogenesis remain unclear. Similarly, nitration of protein could also contribute to disease pathogenesis. To assess the status of lipid peroxidation and/or RONS, autoimmune-prone female MRL+/+ mice (5-week old) were treated with trichloroethene (TCE), an environmental contaminant known to induce autoimmune response, for 48 weeks (0.5 mg/ml via drinking water), and formation of antibodies to LPDA-protein adducts was followed in the sera of control and TCE-treated mice. TCE treatment led to greater formation of both anti-MDA- and -HNE-protein adduct antibodies and higher serum iNOS and nitrotyrosine levels. The increase in TCE-induced oxidative stress was associated with increases in anti-nuclear-, anti-ssDNA- and anti-dsDNA-antibodies. These findings suggest that TCE exposure not only leads to oxidative/nitrosative stress, but is also associated with induction/exacerbation of autoimmune response in MRL+/+ mice. Further interventional studies are needed to establish a causal role of RONS in TCE-mediated autoimmunity

  3. The 6-phosphogluconate Dehydrogenase Genes Are Responsive to Abiotic Stresses in Rice

    Fu-Yun Hou; Ji Huang; Shan-Lin Yu; Hong-Sheng Zhang

    2007-01-01

    Glucose-6-phosphate dehydrogenase (G6PDH, E.C. 1.1.1.49) and 6-phosphogluconate dehydrogenase (6PGDH, EC 1.1.1.44) are both key enzymes of the pentose phosphate pathway (PPP). The OsG6PDH1 and Os6PGDH1 genes encoding cytosolic G6PDH and cytosolic 6PGDH were isoiated from rice (Oryza satlva L.). We have shown that Os6PGDH1 gene was up-regulated by salt stress. Here we reported the isolation and characterization of Os6PGDH2 from rice, which encode the plastidic counterpart of 6PGDH. Genomic organization analysis indicated that OsG6PDH1 and OsG6PDH2 genes contain multiple introns, whereas two Os6PGDH1 and Os6PGDH2 genes have no introns in their translated regions. In a step towards understanding the functions of the pentose phosphate pathway in plants in response to various abiotic stresses, the expressions of four genes in the rice seedlings treated by drought, cold, high salinity and abscisic acid (ABA) were investigated. The results show that OsG6PDH1 and OsG6PDH2 are not markedly regulated by the abiotic stresses detected. However, the transcript levels of both Os6PGDH1 and Os6PGDH2 are up-regulated in rice seedlings under drought, cold, high salinity and ABA treatments. Meanwhile,the enzyme activities of G6PDH and 6PGDH in the rice seedlings treated by various ablotlc stresses were investigated.Like the mRNA expression patterns, G6PDH activity remains constant but the 6PGDH increases steadily during the treatments. Taken together, we suggest that the pentose phosphate pathway may play an important role in rice responses to abiotlc stresses and the second key enzyme of PPP, 6PGDH, may function as a regulator controlling the efficiency of the pathway under abiotic stresses.

  4. Calcium-Dependent Protein Kinase CPK21 Functions in Abiotic Stress Response in Arabidopsis thaliana

    Sandra Franz; Britta Ehlert; Anja Liese; Joachim Kurth; Anne-Claire Cazalé; Tina Romeis

    2011-01-01

    Calcium-dependent protein kinases(CDPKs)comprise a family of plant serine/threonine protein kinases in which the calcium sensing domain and the kinase effector domain are combined within one molecule.So far,a biological function in abiotic stress signaling has only been reported for few CDPK isoforms,whereas the underlying biochemical mechanism for these CDPKs is still mainly unknown.Here,we show that CPK21 from Arabidopsis thaliana is biochemically activated in vivo in response to hyperosmotic stress.Loss-of-function seedlings of cpk21 are more tolerant to hyperosmotic stress and mutant plants show increased stress responses with respect to marker gene expression and metabolite accumulation.In transgenic Arabidopsis complementation lines in the cpk21 mutant background,in which either CPK21 wildtype,or a full-length enzyme variant carrying an amino-acid substitution were stably expressed,stress responsitivity was restored by CPK21 but not with the kinase inactive variant.The biochemical characterization of in planta synthesized and purified CPK21 protein revealed that within the calcium-binding domain,N-terminal EF1- and EF2-motifs compared to C-terminal EF3- and EF4-motifs differ in their contribution to calcium-regulated kinase activity,suggesting a crucial role for the N-terminal EF-hand pair.Our data provide evidence for CPK21 contributing in abiotic stress signaling and suggest that the N-terminal EF-hand pair is a calcium-sensing determinant controlling specificity of CPK21 function.

  5. Exploring the Response of Plants Grown under Uranium Stress

    Uranium is a natural element which is mainly redistributed in the environment due to human activity, including accidents and spillages. Plants may be useful in cleaning up after incidents, although little is yet known about the relationship between uranium speciation and plant response. We analyzed the impact of different uranium (U) treatments on three plant species namely sunflower, oilseed rape and wheat. Using inductively coupled plasma mass spectrometry elemental analysis, together with a panel of imaging techniques including scanning electron microscopy coupled with energy dispersive spectroscopy, transmission electron microscopy and particle-induced X-ray emission spectroscopy, we have recently shown how chemical speciation greatly influences the accumulation and distribution of U in plants. Uranyl (UO22+ free ion) is the predominant mobile form in soil surface at low pH in absence of ligands. With the aim to characterize the early plant response to U exposure, complete Arabidopsis transcriptome microarray experiments were conducted on plants exposed to 50 μM uranyl nitrate for 2, 6 and 30 h and highlighted a set of 111 genes with modified expression at these three time points. Quantitative real-time RT-PCR experiments confirmed and completed CATMA micro-arrays results allowing the characterization of biological processes perturbed by U. Functional categorization of deregulated genes emphasizes oxidative stress, cell wall biosynthesis and hormone biosynthesis and signaling. We showed that U stress is perceived by plant cells like a phosphate starvation stress since several phosphate deprivation marker genes were deregulated by U and also highlighted perturbation of iron homeostasis by U. Hypotheses are presented to explain how U perturbs the iron uptake and signaling response. These results give preliminary insights into the pathways affected by uranyl uptake, which will be of interest for engineering plants to help clean areas contaminated with U. (authors)

  6. Exploring the Response of Plants Grown under Uranium Stress

    Doustaly, Fany; Berthet, Serge; Bourguignon, Jacques [CEA, iRTSV, Laboratoire de Physiologie Cellulaire Vegetale, UMR 5168 CEA-CNRS-INRA-Univ. Grenoble Alpes (France); Combes, Florence; Vandenbrouck, Yves [CEA, iRTSV, Laboratoire de Biologie a Grande Echelle, EDyP, CEA-Grenoble (France); Carriere, Marie [CEA, INAC, LAN, UMR E3 CEA-Universite Joseph Fourier, Grenoble (France); Vavasseur, Alain [CEA, IBEB, LBDP, Saint Paul lez Durance, CEA Cadarache (France)

    2014-07-01

    Uranium is a natural element which is mainly redistributed in the environment due to human activity, including accidents and spillages. Plants may be useful in cleaning up after incidents, although little is yet known about the relationship between uranium speciation and plant response. We analyzed the impact of different uranium (U) treatments on three plant species namely sunflower, oilseed rape and wheat. Using inductively coupled plasma mass spectrometry elemental analysis, together with a panel of imaging techniques including scanning electron microscopy coupled with energy dispersive spectroscopy, transmission electron microscopy and particle-induced X-ray emission spectroscopy, we have recently shown how chemical speciation greatly influences the accumulation and distribution of U in plants. Uranyl (UO{sub 2}{sup 2+} free ion) is the predominant mobile form in soil surface at low pH in absence of ligands. With the aim to characterize the early plant response to U exposure, complete Arabidopsis transcriptome microarray experiments were conducted on plants exposed to 50 μM uranyl nitrate for 2, 6 and 30 h and highlighted a set of 111 genes with modified expression at these three time points. Quantitative real-time RT-PCR experiments confirmed and completed CATMA micro-arrays results allowing the characterization of biological processes perturbed by U. Functional categorization of deregulated genes emphasizes oxidative stress, cell wall biosynthesis and hormone biosynthesis and signaling. We showed that U stress is perceived by plant cells like a phosphate starvation stress since several phosphate deprivation marker genes were deregulated by U and also highlighted perturbation of iron homeostasis by U. Hypotheses are presented to explain how U perturbs the iron uptake and signaling response. These results give preliminary insights into the pathways affected by uranyl uptake, which will be of interest for engineering plants to help clean areas contaminated with

  7. Morphogenetic responses ofPopulus alba L. under salt stress

    Mejda Abassi; Khaled Mguis; Zoubeir Béjaoui; Ali Albouchi

    2014-01-01

    The morphogenetic responses to salt stress of TunisianPopu-lus alba clones were studied in order to promote their plantation in dam-aged saline areas. One year-old plants of threeP. alba clones (MA-104, MA-195 and OG) were subjected to progressive salt stress by irrigation during two consecutive years. The plants were grown in a nursery, inside plastic receptacles containing sandy soil and were irrigated with tap water (control) or 3-6 g/l NaCl solution. During this study, leaf epinasty, elongation rate, vigor, internode length, plant architecture, and number of buds were evaluated. Test clone response was highly dependent on the applied treatment and degree of accommodation.The most pronounced alterations were induced under 6g/l of NaCl treatment including leaf epinasty, leaf elongation rate delay, vigor decrease, internode length shortening, and morphogenetic modifications. These responses were less noticeable in the MA-104 clone with respect to the two other clones. The salt effect induced a delay in the leaf elongation rate on the MA-195 and OG clones leading to an early leaf maturity. The vigour and internode length of the MA-104 clone was less affected than the other clones. The OG clone was the most salt-sensitive thus, it developed shorter branches and more buds number than MA-195 and MA-104. The effect of long-term salt stress was to induce early flowering of theP. alba clones which suggests that mechanism of salt accommodation could be devel-oped.

  8. The characteristics of expansins in wheat coleoptiles and their responses to water stress.

    Gao, Qiang; Guo, Qi-Fang; Xing, Shi-Chao; Zhao, Mei-Rong; Li, Feng; Wang, Wei

    2007-10-01

    As the key regulators of cell wall extension during plant growth, expansins play an important role in regulating the development and response of plants to adverse environment. The characteristics of expansins in wheat coleoptiles and their responses to water stress were studied. Expansin proteins were extracted from wheat coleoptiles by the methods of Hepes or SDS. The activities of expansins were measured with an improved extensometer and the amount of expansins was measured by immunoblot analysis with the expansin antibody. The results showed that in coleoptiles, the extension of native cell walls depended on acidic pH, and the expansins were found to be located at cell walls by location analysis. Expansins from wheat coleoptiles could induce cell wall extension both of cucumber hypocotyls and coleoptiles, and vice versa, albeit with differences noted in extension activity. The changes in activity and abundance of expansins in wheat coleoptiles in response to water stress suggest that expansins may play a significant role in the tolerance of wheat plants to water stress. PMID:17960043

  9. Individual differences in cortisol responses to a laboratory speech task and their relationship to responses to stressful daily events

    van Eck, M; Nicolson, N.A; Berkhof, J.; Sulon, J

    1996-01-01

    A Stress Inducing Speech Task was used to investigate the contribution of perceived stress, individual traits, and current mood states to individual differences in salivary cortisol responses. Additionally, we examined the correspondence between laboratory baseline cortisol levels and overall levels

  10. Metabolic Response of Pakchoi Leaves to Amino Acid Nitrogen

    WANG Xiao-li; YU Wen-juan; ZHOU Qian; HAN Rui-feng; HUANG Dan-feng

    2014-01-01

    Different nitrogen (N) forms may cause changes in the metabolic profiles of plants. However, few studies have been conducted on the effects of amino acid-N on plant metabolic proifles. The main objective of this study was to identify primary metabolites associated with amino acid-N (Gly, Gln and Ala) through metabolic proifle analysis using gas chromatography-mass spectrometry (GC-MS). Plants of pakchoi (Brassica campestris L. ssp. chinensis L.), Huawang and Wuyueman cultivars, were grown with different nitrogen forms (i.e., Gly, Gln, Ala, NO3--N, and N starvation) applied under sterile hydroponic conditions. The fresh weight and plant N accumulation of Huawang were greater than those of Wuyueman, which indicates that the former exhibited better N-use efficiency than the latter. The physiological performances of the applied N forms were generally in the order of NO3--N>Gln>Gly>Ala. The metabolic analysis of leaf polar extracts revealed 30 amino acid N-responsive metabolites in the two pakchoi cultivars, mainly consisting of sugars, amino acids, and organic acids. Changes in the carbon metabolism of pakchoi leaves under amino acid treatments occurred via the accumulation of fructose, glucose, xylose, and arabinose. Disruption of amino acid metabolism resulted in accumulation of endogenous Gly in Gly treatment, Pro in Ala treatment, and Asn in three amino acid (Gly, Gln and Ala) treatments. By contrast, the levels of endogenous Gln and Leu decreased. However, this reduction varied among cultivars and amino acid types. Amino acid-N supply also affected the citric acid cycle, namely, the second stage of respiration, where leaves in Gly, Gln and Ala treatments contained low levels of malic, citric and succinic acids compared with leaves in NO3--N treatments. No signiifcant difference in the metabolic responses was observed between the two cultivars which differed in their capability to use N. The response of primary metabolites in pakchoi leaves to amino acid-N supply

  11. Mitochondrial and Chloroplast Stress Responses Are Modulated in Distinct Touch and Chemical Inhibition Phases1[OPEN

    Ivanova, Aneta; Millar, A. Harvey; Whelan, James

    2016-01-01

    Previous studies have identified a range of transcription factors that modulate retrograde regulation of mitochondrial and chloroplast functions in Arabidopsis (Arabidopsis thaliana). However, the relative importance of these regulators and whether they act downstream of separate or overlapping signaling cascades is still unclear. Here, we demonstrate that multiple stress-related signaling pathways, with distinct kinetic signatures, converge on overlapping gene sets involved in energy organelle function. The transcription factor ANAC017 is almost solely responsible for transcript induction of marker genes around 3 to 6 h after chemical inhibition of organelle function and is a key regulator of mitochondrial and specific types of chloroplast retrograde signaling. However, an independent and highly transient gene expression phase, initiated within 10 to 30 min after treatment, also targets energy organelle functions, and is related to touch and wounding responses. Metabolite analysis demonstrates that this early response is concurrent with rapid changes in tricarboxylic acid cycle intermediates and large changes in transcript abundance of genes encoding mitochondrial dicarboxylate carrier proteins. It was further demonstrated that transcription factors AtWRKY15 and AtWRKY40 have repressive regulatory roles in this touch-responsive gene expression. Together, our results show that several regulatory systems can independently affect energy organelle function in response to stress, providing different means to exert operational control. PMID:27208304

  12. κ Opioid Receptor Antagonism and Prodynorphin Gene Disruption Block Stress-Induced Behavioral Responses

    McLaughlin, Jay P.; Marton-Popovici, Monica; Chavkin, Charles

    2003-01-01

    Previous studies have demonstrated that stress may increase prodynorphin gene expression, and κ opioid agonists suppress drug reward. Therefore, we tested the hypothesis that stress-induced release of endogenous dynorphin may mediate behavioral responses to stress and oppose the rewarding effects of cocaine. C57Bl/6 mice subjected to repeated forced swim testing (FST) using a modified Porsolt procedure at 30°C showed a characteristic stress-induced immobility response and a stress-induced ana...

  13. Enhancement of Latent Inhibition by Chronic Mild Stress in Rats Submitted to Emotional Response Conditioning

    Liana Lins Melo; de Moraes Ferrari, Elenice A.; Nancy Airoldi Teixeira; Guy Sandner

    2003-01-01

    This work evaluated the influence of chronic mild stress on latent inhibition (LI) in rats, using a conditioned emotional response (CER) procedure. Rats were assigned to four groups: a non pre-exposed control group (NPC), a non pre-exposed stressed group (NPS), a preexposed control group (PC), and a pre-exposed stressed group (PS). Stressed animals were submitted to a chronic mild stress (CMS) regimen for three weeks. The off-baseline conditioned emotional response procedure had four phases: ...

  14. Cloning and Expression Analysis of OsNADPH1 Gene from Rice in Drought Stress Response

    CHEN Jing; WAN Jia; JIANG Hua; GAO Xiao-ling; WANG Ping-rong; XI Jiang; XU Zheng-jun

    2006-01-01

    An experiment was conducted to compare the mRNA expression difference in rice leaves and roots under drought stress and normal conditions using Fluorescent Differential Display (FDD) method. One positive fragment was isolated by combination of the H. A. Yellow-PAGE (contained 0.1% H. A. Yellow) separation and macroarray screening methods. Compared to Arabidopsis thaliana NADPH oxidoreductase gene, it has 96% identity. The cDNA was 1423 bp, and contained a complete open reading frame of 1048 bp encoding a protein with 345 amino acid residues. Moreover, the gene expression level was higher under drought stress than that under normal conditions. The possible role of NADPH oxidoreductase gene under drought response was also discussed.

  15. P53 family and cellular stress responses in cancer

    Johanna ePflaum

    2014-10-01

    Full Text Available p53 is an important tumor suppressor gene, which is stimulated by cellular stress like ionizing radiation, hypoxia, carcinogens and oxidative stress. Upon activation p53 leads to cell cycle arrest and promotes DNA repair or induces apoptosis via several pathways. p63 and p73 are structural homologs of p53 that can act similarly to the protein but also hold functions distinct from p53. Today more than forty different isoforms of the p53 family members are known. They result from transcription via different promoters and alternative splicing. Some isoforms have carcinogenic properties and mediate resistance to chemotherapy. Therefore, expression patterns of the p53 family genes can offer prognostic information in several malignant tumors. Furthermore, the p53 family constitutes a potential target for cancer therapy. Small molecules (e.g. Nutlins, RITA, PRIMA-1, and MIRA-1 among others have been objects of intense research interest in recent years. They restore pro-apoptotic wild-type p53 function and were shown to break chemotherapeutic resistance. Due to p53 family interactions small molecules also influence p63 and p73 activity. Thus, the members of the p53 family are key players in the cellular stress response in cancer and are expected to grow in importance as therapeutic targets.

  16. Historical temperature variability affects coral response to heat stress.

    Jessica Carilli

    Full Text Available Coral bleaching is the breakdown of symbiosis between coral animal hosts and their dinoflagellate algae symbionts in response to environmental stress. On large spatial scales, heat stress is the most common factor causing bleaching, which is predicted to increase in frequency and severity as the climate warms. There is evidence that the temperature threshold at which bleaching occurs varies with local environmental conditions and background climate conditions. We investigated the influence of past temperature variability on coral susceptibility to bleaching, using the natural gradient in peak temperature variability in the Gilbert Islands, Republic of Kiribati. The spatial pattern in skeletal growth rates and partial mortality scars found in massive Porites sp. across the central and northern islands suggests that corals subject to larger year-to-year fluctuations in maximum ocean temperature were more resistant to a 2004 warm-water event. In addition, a subsequent 2009 warm event had a disproportionately larger impact on those corals from the island with lower historical heat stress, as indicated by lower concentrations of triacylglycerol, a lipid utilized for energy, as well as thinner tissue in those corals. This study indicates that coral reefs in locations with more frequent warm events may be more resilient to future warming, and protection measures may be more effective in these regions.

  17. Increased oxidative stress and impaired antioxidant response in Lafora disease.

    Romá-Mateo, Carlos; Aguado, Carmen; García-Giménez, José Luis; Ibáñez-Cabellos, José Santiago; Seco-Cervera, Marta; Pallardó, Federico V; Knecht, Erwin; Sanz, Pascual

    2014-10-01

    Lafora Disease (LD, OMIM 254780, ORPHA501) is a fatal neurodegenerative disorder characterized by the presence of glycogen-like intracellular inclusions called Lafora bodies and caused, in the vast majority of cases, by mutations in either EPM2A or EPM2B genes, encoding respectively laforin and malin. In the last years, several reports have revealed molecular details of these two proteins and have identified several processes affected in LD, but the pathophysiology of the disease still remains largely unknown. Since autophagy impairment has been reported as a characteristic treat in both Lafora disease cell and animal models, and as there is a link between autophagy and mitochondrial performance, we sought to determine if mitochondrial function could be altered in those models. Using fibroblasts from LD patients, deficient in laforin or malin, we found mitochondrial alterations, oxidative stress and a deficiency in antioxidant enzymes involved in the detoxification of reactive oxygen species (ROS). Similar results were obtained in brain tissue samples from transgenic mice deficient in either the EPM2A or EPM2B genes. Furthermore, in a proteomic analysis of brain tissue obtained from Epm2b-/- mice, we observed an increase in a modified form of peroxirredoxin-6, an antioxidant enzyme involved in other neurological pathologies, thus corroborating an alteration of the redox condition. These data support that oxidative stress produced by an increase in ROS production and an impairment of the antioxidant enzyme response to this stress play an important role in development of LD. PMID:26461389

  18. Autophagic response to cell culture stress in pluripotent stem cells.

    Gregory, Siân; Swamy, Sushma; Hewitt, Zoe; Wood, Andrew; Weightman, Richard; Moore, Harry

    2016-05-01

    Autophagy is an important conserved cellular process, both constitutively as a recycling pathway for long lived proteins and as an upregulated stress response. Recent findings suggest a fundamental role for autophagic processes in the maintenance of pluripotent stem cell function. In human embryonic stem cells (hESCS), autophagy was investigated by transfection of LC3-GFP to visualize autophagosomes and with an antibody to LC3B protein. The presence of the primary cilium (PC) in hESCs as the site of recruitment of autophagy-related proteins was also assessed. HESCs (mShef11) in vitro displayed basal autophagy which was upregulated in response to deprivation of culture medium replacement. Significantly higher levels of autophagy were exhibited on spontaneous differentiation of hESCs in vitro. The PC was confirmed to be present in hESCs and therefore may serve to coordinate autophagy function. PMID:26385182

  19. Pseudomonas putida attunes morphophysiological, biochemical and molecular responses in Cicer arietinum L. during drought stress and recovery.

    Tiwari, Shalini; Lata, Charu; Chauhan, Puneet Singh; Nautiyal, Chandra Shekhar

    2016-02-01

    Drought is one of the most important abiotic stresses that adversely affect plant growth and yield potential. However, some drought resistant rhizosphere competent bacteria are known to improve plant health and promote growth during abiotic stresses. Present study showed the role of Pseudomonas putida MTCC5279 (RA) in ameliorating drought stress on cv. BG-362 (desi) and cv. BG-1003 (kabuli) chickpea cultivars under in vitro and green house conditions. Polyethylene glycol-induced drought stress severely affected seed germination in both cultivars which was considerably improved on RA-inoculation. Drought stress significantly affected various growth parameters, water status, membrane integrity, osmolyte accumulation, ROS scavenging ability and stress-responsive gene expressions, which were positively modulated upon application of RA in both chickpea cultivars. Quantitative real-time (qRT)-PCR analysis showed differential expression of genes involved in transcription activation (DREB1A and NAC1), stress response (LEA and DHN), ROS scavenging (CAT, APX, GST), ethylene biosynthesis (ACO and ACS), salicylic acid (PR1) and jasmonate (MYC2) signalling in both chickpea cultivars exposed to drought stress and recovery in the presence or absence of RA. The observations imply that RA confers drought tolerance in chickpea by altering various physical, physiological and biochemical parameters, as well as by modulating differential expression of at least 11 stress-responsive genes. To the best of our knowledge, this is the first report on detailed analysis of plant growth promotion and stress alleviation in one month old desi and kabuli chickpea subjected to drought stress for 0, 1, 3 and 7 days and recovery in the presence of a PGPR. PMID:26744996

  20. Melatonin is more effective than ascorbic acid and β-carotene in improvement of gastric mucosal damage induced by intensive stress

    Akinci, Aysin; Esrefoglu, Mukaddes; Cetin, Asli; Ates, Burhan

    2015-01-01

    Introduction Oxidative stress has been considered to play a primary role in the pathogenesis of stress-induced gastric damage. The aim of this study was to investigate the effects of melatonin, ascorbic acid and β-carotene on stress-induced gastric mucosal damage. Material and methods Fifty-six male Wistar albino rats were divided into control, stress, stress + standard diet, stress + saline, stress + melatonin, stress + ascorbic acid and stress + β-carotene groups. The rats from stress group...

  1. A nucleotide metabolite controls stress-responsive gene expression and plant development

    Chen, Hao

    2011-10-19

    Abiotic stress, such as drought and high salinity, activates a network of signaling cascades that lead to the expression of many stress-responsive genes in plants. The Arabidopsis FIERY1 (FRY1) protein is a negative regulator of stress and abscisic acid (ABA) signaling and exhibits both an inositol polyphosphatase and a 3?,5?-bisphosphate nucleotidase activity in vitro. The FRY1 nucleotidase degrades the sulfation byproduct 3?-phosphoadenosine-5?-phosphate (PAP), yet its in vivo functions and particularly its roles in stress gene regulation remain unclear. Here we developed a LC-MS/MS method to quantitatively measure PAP levels in plants and investigated the roles of this nucleotidase activity in stress response and plant development. It was found that PAP level was tightly controlled in plants and did not accumulate to any significant level either under normal conditions or under NaCl, LiCl, cold, or ABA treatments. In contrast, high levels of PAP were detected in multiple mutant alleles of FRY1 but not in mutants of other FRY1 family members, indicating that FRY1 is the major enzyme that hydrolyzes PAP in vivo. By genetically reducing PAP levels in fry1 mutants either through overexpression of a yeast PAP nucleotidase or by generating a triple mutant of fry1 apk1 apk2 that is defective in the biosynthesis of the PAP precursor 3?-phosphoadenosine-5?-phosphosulfate (PAPS), we demonstrated that the developmental defects and superinduction of stress-responsive genes in fry1 mutants correlate with PAP accumulation in planta. We also found that the hypersensitive stress gene regulation in fry1 requires ABH1 but not ABI1, two other negative regulators in ABA signaling pathways. Unlike in yeast, however, FRY1 overexpression in Arabidopsis could not enhance salt tolerance. Taken together, our results demonstrate that PAP is critical for stress gene regulation and plant development, yet the FRY1 nucleotidase that catabolizes PAP may not be an in vivo salt toxicity target

  2. A nucleotide metabolite controls stress-responsive gene expression and plant development.

    Hao Chen

    Full Text Available Abiotic stress, such as drought and high salinity, activates a network of signaling cascades that lead to the expression of many stress-responsive genes in plants. The Arabidopsis FIERY1 (FRY1 protein is a negative regulator of stress and abscisic acid (ABA signaling and exhibits both an inositol polyphosphatase and a 3',5'-bisphosphate nucleotidase activity in vitro. The FRY1 nucleotidase degrades the sulfation byproduct 3'-phosphoadenosine-5'-phosphate (PAP, yet its in vivo functions and particularly its roles in stress gene regulation remain unclear. Here we developed a LC-MS/MS method to quantitatively measure PAP levels in plants and investigated the roles of this nucleotidase activity in stress response and plant development. It was found that PAP level was tightly controlled in plants and did not accumulate to any significant level either under normal conditions or under NaCl, LiCl, cold, or ABA treatments. In contrast, high levels of PAP were detected in multiple mutant alleles of FRY1 but not in mutants of other FRY1 family members, indicating that FRY1 is the major enzyme that hydrolyzes PAP in vivo. By genetically reducing PAP levels in fry1 mutants either through overexpression of a yeast PAP nucleotidase or by generating a triple mutant of fry1 apk1 apk2 that is defective in the biosynthesis of the PAP precursor 3'-phosphoadenosine-5'-phosphosulfate (PAPS, we demonstrated that the developmental defects and superinduction of stress-responsive genes in fry1 mutants correlate with PAP accumulation in planta. We also found that the hypersensitive stress gene regulation in fry1 requires ABH1 but not ABI1, two other negative regulators in ABA signaling pathways. Unlike in yeast, however, FRY1 overexpression in Arabidopsis could not enhance salt tolerance. Taken together, our results demonstrate that PAP is critical for stress gene regulation and plant development, yet the FRY1 nucleotidase that catabolizes PAP may not be an in vivo salt

  3. Visualization of early stress responses in plant leaves

    Chaerle, Laury; vandeVen, Martin J.; Valcke, Roland L.; Van Der Straeten, Dominique

    2002-03-01

    Plant leaves possess microscopic valves, called stomata, that enable control of transpirational water loss. In case of water shortage, stomata close, resulting in decreased transpirational cooling. The ensuing temperature increase is readily visualized by thermography. Salicylic acid, a central compound in the defense of plants against pathogens, also closes stomata in several species. In previous work, thermography permitted to monitor an increase in temperature after infection of resistant tobacco by tobacco mosaic virus, before visual symptoms appeared. Furthermore, cell death was visualized with high contrast in both tobacco and Arabidopsis. In addition to transpiration, photosynthetic assimilation is a key physiological parameter. If the amount of light absorbed by chlorophyll exceeds the capacity of the photosynthetic chain, the surplus is dissipated as light of longer wavelength. This phenomenon is known as chlorophyll fluorescence. If a plant leaf is affected by stress, photosynthesis is impaired resulting in a bigger share of non-utilized light energy emitted as fluorescence. The potential of an automated imaging setup combining thermal and fluorescence imaging was shown by monitoring spontaneous cell death in tobacco. This represents a first step to multispectral characterization of a wide range of emerging stresses, which likely affect one or both key physiological parameters.

  4. Effect of salicylic acid on the growth photosynthesis and carbohydrate metabolism in salt stressed maize plants

    Aqueous solutions of salicylic acid as a spray to Na CI-treated corn (Zea mays L,) significantly increased the growth of shoots and roots as measured after seven days of treatment. Spraying of salicylic acid caused significant increases in the activity of both ribulose 1,5 bisphosphate carboxylase (rubisco) enzyme and photosynthetic pigments. Moreover, salicylic acid treatment induced high values of soluble carbohydrate fractions in salt stressed plants as compared with salicylic acid treated samples. These data suggest that salicylic acid might improve the growth pattern of NaCl-treated maize plants via increasing the rate of photosynthesis and carbohydrate metabolism

  5. Neuronatin is a stress-responsive protein of rod photoreceptors.

    Shinde, Vishal; Pitale, Priyamvada M; Howse, Wayne; Gorbatyuk, Oleg; Gorbatyuk, Marina

    2016-07-22

    Neuronatin (NNAT) is a small transmembrane proteolipid that is highly expressed in the embryonic developing brain and several other peripheral tissues. This study is the first to provide evidence that NNAT is detected in the adult retina of various adult rod-dominant mammals, including wild-type (WT) rodents, transgenic rodents expressing mutant S334ter, P23H, or T17M rhodopsin, non-human primates, humans, and cone-dominant tree shrews. Immunohistochemical and quantitative real time polymerase chain reaction (qRT-PCR) analyses were applied to detect NNAT. Confocal microscopy analysis revealed that NNAT immunofluorescence is restricted to the outer segments (OSs) of photoreceptors without evidence of staining in other retinal cell types across all mammalian species. Moreover, in tree shrew retinas, we found NNAT to be co-localized with rhodopsin, indicating its predominant expression in rods. The rod-derived expression of NNAT was further confirmed by qRT-PCR in isolated rod photoreceptor cells. We also used these cells to mimic cellular stress in transgenic retinas by treating them with the endoplasmic reticulum stress inducer, tunicamycin. Thus, our data revealed accumulation of NNAT around the nucleus as compared to dispersed localization of NNAT within control cells. This distribution coincided with the partial intracellular mislocalization of NNAT to the outer nuclear layer observed in transgenic retinas. In addition, stressed retinas demonstrated an increase of NNAT mRNA and protein levels. Therefore, our study demonstrated that NNAT is a novel stress-responsive protein with a potential structural and/or functional role in adult mammalian retinas. PMID:27109921

  6. Physiological responses to water stress and waterlogging in Nothofagus species.

    Sun, O J; Sweet, G B; Whitehead, D; Buchan, G D

    1995-10-01

    Gas exchange and water relations were investigated in Nothofagus solandri var. cliffortioides (Hook. f.) Poole (mountain beech) and Nothofagus menziesii (Hook. f.) Oerst (silver beech) seedlings in response to water stress and waterlogging. At soil matric potentials (Psi(soil)) above -0.005 MPa, N. solandri had significantly higher photosynthetic rates (A), and stomatal and residual conductances (g(sw) and g(rc)), and lower predawn xylem water potentials (Psi(predawn)) than N. menziesii. The relative tolerance of plants to water stress was defined in terms of critical soil matric potential (Psi(cri)) and lethal xylem water potential (Psi(lethal)). The estimated values of Psi(cri) and Psi(lethal) were -1.2 and -7 MPa, respectively, for N. solandri, and -0.7 and -4 MPa, respectively, for N. menziesii. Photosynthesis was sustained to a xylem water potential (Psi(xylem)) of -7 MPa in N. solandri compared with -4 MPa in N. menziesii. Following rewatering, both A and Psi(xylem) recovered quickly in N. solandri, whereas the two variables recovered more slowly in N. menziesii. During the development of water stress, nonstomatal inhibition significantly affected A in both N. solandri and N. menziesii. Nothofagus menziesii was more susceptible to inhibition of A by waterlogging than N. solandri. However, the tolerance of N. solandri to severe waterlogging was also limited as a result of a failure to form adventitious roots, suggesting a lack of adaptation to these conditions. The differences in tolerance to water stress and waterlogging between the two species are consistent with the distribution patterns of N. solandri and N. menziesii in New Zealand. PMID:14965996

  7. Differential response of hippocampal subregions to stress and learning.

    Darby F Hawley

    Full Text Available The hippocampus has two functionally distinct subregions-the dorsal portion, primarily associated with spatial navigation, and the ventral portion, primarily associated with anxiety. In a prior study of chronic unpredictable stress (CUS in rodents, we found that it selectively enhanced cellular plasticity in the dorsal hippocampal subregion while negatively impacting it in the ventral. In the present study, we determined whether this adaptive plasticity in the dorsal subregion would confer CUS rats an advantage in a spatial task-the radial arm water maze (RAWM. RAWM exposure is both stressful and requires spatial navigation, and therefore places demands simultaneously upon both hippocampal subregions. Therefore, we used Western blotting to investigate differential expression of plasticity-associated proteins (brain derived neurotrophic factor [BDNF], proBDNF and postsynaptic density-95 [PSD-95] in the dorsal and ventral subregions following RAWM exposure. Lastly, we used unbiased stereology to compare the effects of CUS on proliferation, survival and neuronal differentiation of cells in the dorsal and ventral hippocampal subregions. We found that CUS and exposure to the RAWM both increased corticosterone, indicating that both are stressful; nevertheless, CUS animals had significantly better long-term spatial memory. We also observed a subregion-specific pattern of protein expression following RAWM, with proBDNF increased in the dorsal and decreased in the ventral subregion, while PSD-95 was selectively upregulated in the ventral. Finally, consistent with our previous study, we found that CUS most negatively affected neurogenesis in the ventral (compared to the dorsal subregion. Taken together, our data support a dual role for the hippocampus in stressful experiences, with the more resilient dorsal portion undergoing adaptive plasticity (perhaps to facilitate escape from or neutralization of the stressor, and the ventral portion involved in

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

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

    2016-08-01

    Abiotic stress has been shown to significantly limit the growth and productivity of crops. NAC transcription factors play essential roles in response to various abiotic stresses. However, only little information regarding stress-related NAC genes is available in maize. Here, we cloned a maize NAC transcription factor ZmNAC55 and identified its function in drought stress. Transient expression and transactivation assay demonstrated that ZmNAC55 was localized in the nucleus and had transactivation activity. Expression analysis of ZmNAC55 in maize showed that this gene was induced by drought, high salinity and cold stresses and by abscisic acid (ABA). Promoter analysis demonstrated that multiple stress-related cis-acting elements exist in promoter region of ZmNAC55. Overexpression of ZmNAC55 in Arabidopsis led to hypersensitivity to ABA at the germination stage, but enhanced drought resistence compared to wild-type seedlings. Transcriptome analysis identified a number of differentially expressed genes between 35S::ZmNAC55 transgenic and wild-type plants, and many of which are involved in stress response, including twelve qRT-PCR confirmed well-known drought-responsive genes. These results highlight the important role of ZmNAC55 in positive regulates of drought resistence, and may have potential applications in transgenic breeding of drought-tolerant crops. PMID:27085597

  9. Assessing Cd-induced stress from plant spectral response

    Kancheva, Rumiana; Georgiev, Georgi

    2014-10-01

    Remote sensing plays a significant role in local, regional and global monitoring of land covers. Ecological concerns worldwide determine the importance of remote sensing applications for the assessment of soil conditions, vegetation health and identification of stress-induced changes. The extensive industrial growth and intensive agricultural land-use arise the serious ecological problem of environmental pollution associated with the increasing anthropogenic pressure on the environment. Soil contamination is a reason for degradation processes and temporary or permanent decrease of the productive capacity of land. Heavy metals are among the most dangerous pollutants because of their toxicity, persistent nature, easy up-take by plants and long biological half-life. This paper takes as its focus the study of crop species spectral response to Cd pollution. Ground-based experiments were performed, using alfalfa, spring barley and pea grown in Cd contaminated soils and in different hydroponic systems under varying concentrations of the heavy metal. Cd toxicity manifested itself by inhibition of plant growth and synthesis of photosynthetic pigments. Multispectral reflectance, absorbance and transmittance, as well as red and far red fluorescence were measured and examined for their suitability to detect differences in plant condition. Statistical analysis was performed and empirical relationships were established between Cd concentration, plant growth variables and spectral response Various spectral properties proved to be indicators of plant performance and quantitative estimators of the degree of the Cd-induced stress.

  10. Temporal evolution of the Arabidopsis oxidative stress response.

    Mahalingam, Ramamurthy; Shah, Nigam; Scrymgeour, Alexandra; Fedoroff, Nina

    2005-03-01

    We have carried out a detailed analysis of the changes in gene expression levels in Arabidopsis thaliana ecotype Columbia (Col-0) plants during and for 6 h after exposure to ozone (O3) at 350 parts per billion (ppb) for 6 h. This O3 exposure is sufficient to induce a marked transcriptional response and an oxidative burst, but not to cause substantial tissue damage in Col-0 wild-type plants and is within the range encountered in some major metropolitan areas. We have developed analytical and visualization tools to automate the identification of expression profile groups with common gene ontology (GO) annotations based on the sub-cellular localization and function of the proteins encoded by the genes, as well as to automate promoter analysis for such gene groups. We describe application of these methods to identify stress-induced genes whose transcript abundance is likely to be controlled by common regulatory mechanisms and summarized our findings in a temporal model of the stress response. PMID:15988565

  11. A Blm-Recql5 partnership in replication stress response

    Xincheng Lu; Hua Lou; Guangbin Luo

    2011-01-01

    Deficiencies in DNA damage response and repair not only can result in genome instability and cancer predisposition, but also can render the cancer cells intrinsically more vulnerable to certain types of DNA damage insults. Particularly, replication stress is both a hallmark of human cancers and a common instigator for genome instability and cell death. Here, we review our work based on the genetic knockout studies on Blm and Recql5, two members of the mammalian RecQ helicase family. These studies have uncovered a unique partnership between these two helicases in the implementation of proper mitigation strategies under different circumstances to promote DNA replication and cell survival and suppress genome instability and cancer. In particular, current studies have revealed the presence of a novel Recql5/RECQL5-dependent mechanism for suppressing replication fork collapse in response to global replication fork stalling following exposure to camptothecin (CPT), a topoisomerase I inhibitor, and a potent inhibitor of DNA replication. The unique partnership between Blm and Recql5 in coping with the challenge imposed by replication stress is discussed. In addition, given that irinotecan and topotecan, two CPT derivatives, are currently used in clinic for treating human cancer patients with very promising results, the potential implication of the new findings from these studies in anticancer treatments is also discussed.

  12. The genetic basis of variation in clean lineages of Saccharomyces cerevisiae in response to stresses encountered during bioethanol fermentations.

    Darren Greetham

    Full Text Available Saccharomyces cerevisiae is the micro-organism of choice for the conversion of monomeric sugars into bioethanol. Industrial bioethanol fermentations are intrinsically stressful environments for yeast and the adaptive protective response varies between strain backgrounds. With the aim of identifying quantitative trait loci (QTL's that regulate phenotypic variation, linkage analysis on six F1 crosses from four highly divergent clean lineages of S. cerevisiae was performed. Segregants from each cross were assessed for tolerance to a range of stresses encountered during industrial bioethanol fermentations. Tolerance levels within populations of F1 segregants to stress conditions differed and displayed transgressive variation. Linkage analysis resulted in the identification of QTL's for tolerance to weak acid and osmotic stress. We tested candidate genes within loci identified by QTL using reciprocal hemizygosity analysis to ascertain their contribution to the observed phenotypic variation; this approach validated a gene (COX20 for weak acid stress and a gene (RCK2 for osmotic stress. Hemizygous transformants with a sensitive phenotype carried a COX20 allele from a weak acid sensitive parent with an alteration in its protein coding compared with other S. cerevisiae strains. RCK2 alleles reveal peptide differences between parental strains and the importance of these changes is currently being ascertained.

  13. Empathy and Stress Related Neural Responses in Maternal Decision Making

    S. Shaun Ho

    2014-06-01

    Full Text Available Mothers need to make caregiving decisions to meet the needs of children, which may or may not result in positive child feedback. Variations in caregivers’ emotional reactivity to unpleasant child-feedback may be partially explained by their dispositional empathy levels. Furthermore, empathic response to the child’s unpleasant feedback likely helps mothers to regulate their own stress. We investigated the relationship between maternal dispositional empathy, stress reactivity, and neural correlates of child feedback to caregiving decisions. In Part 1 of the study, 33 female participants were recruited to undergo a lab-based mild stressor, the Social Evaluation Test (SET, and then in Part 2 of the study, a subset of the participants, fourteen mothers, performed a Parenting Decision Making Task (PDMT in an fMRI setting. Four dimensions of dispositional empathy based on the Interpersonal Reactivity Index were measured in all participants – Personal Distress, Empathic Concern, Perspective Taking, and Fantasy. Overall, we found that the Personal Distress and Perspective Taking were associated with greater and lesser cortisol reactivity, respectively. The four types of empathy were distinctly associated with the negative (versus positive child feedback activation in the brain. Personal Distress was associated with amygdala and hypothalamus activation, Empathic Concern with the left ventral striatum, ventrolateral prefrontal cortex (VLPFC, and supplemental motor area (SMA activation, and Fantasy with the septal area, right SMA and VLPFC activation. Interestingly, hypothalamus-septal coupling during the negative feedback condition was associated with less PDMT-related cortisol reactivity. The roles of distinct forms of dispositional empathy in neural and stress responses are discussed.

  14. Stress responsiveness predicts individual variation in mate selectivity.

    Vitousek, Maren N; Romero, L Michael

    2013-06-15

    Steroid hormones, including glucocorticoids, mediate a variety of behavioral and physiological processes. Circulating hormone concentrations vary substantially within populations, and although hormone titers predict reproductive success in several species, little is known about how individual variation in circulating hormone concentrations is linked with most reproductive behaviors in free-living organisms. Mate choice is an important and often costly component of reproduction that also varies substantially within populations. We examined whether energetically costly mate selection behavior in female Galápagos marine iguanas (Amblyrhynchus cristatus) was associated with individual variation in the concentrations of hormones previously shown to differ between reproductive and non-reproductive females during the breeding season (corticosterone and testosterone). Stress-induced corticosterone levels - which are suppressed in female marine iguanas during reproduction - were individually repeatable throughout the seven-week breeding period. Mate selectivity was strongly predicted by individual variation in stress-induced corticosterone: reproductive females that secreted less corticosterone in response to a standardized stressor assessed more displaying males. Neither baseline corticosterone nor testosterone predicted variation in mate selectivity. Scaled body mass was not significantly associated with mate selectivity, but females that began the breeding period in lower body condition showed a trend towards being less selective about potential mates. These results provide the first evidence that individual variation in the corticosterone stress response is associated with how selective females are in their choice of a mate, an important contributor to fitness in many species. Future research is needed to determine the functional basis of this association, and whether transient acute increases in circulating corticosterone directly mediate mate choice behaviors. PMID

  15. DNA damage responses and oxidative stress in dyskeratosis congenita.

    Larisa Pereboeva

    Full Text Available Dyskeratosis congenita (DC is an inherited multisystem disorder of premature aging, cancer predisposition, and bone marrow failure caused by selective exhaustion of highly proliferative cell pools. DC patients also have a poor tolerance to chemo/radiotherapy and bone marrow transplantation. Although critically shortened telomeres and defective telomere maintenance contribute to DC pathology, other mechanisms likely exist. We investigate the link between telomere dysfunction and oxidative and DNA damage response pathways and assess the effects of antioxidants. In vitro studies employed T lymphocytes from DC subjects with a hTERC mutation and age-matched controls. Cells were treated with cytotoxic agents, including Paclitaxel, Etoposide, or ionizing radiation. Apoptosis and reactive oxygen species (ROS were assessed by flow cytometry, and Western blotting was used to measure expression of DNA damage response (DDR proteins, including total p53, p53S15, and p21(WAF. N-acetyl-cysteine (NAC, an antioxidant, was used to modulate cell growth and ROS. In stimulated culture, DC lymphocytes displayed a stressed phenotype, characterized by elevated levels of ROS, DDR and apoptotic markers as well as a proliferative defect that was more pronounced after exposure to cytotoxic agents. NAC partially ameliorated the growth disadvantage of DC cells and decreased radiation-induced apoptosis and oxidative stress. These findings suggest that oxidative stress may play a role in the pathogenesis of DC and that pharmacologic intervention to correct this pro-oxidant imbalance may prove useful in the clinical setting, potentially alleviating untoward toxicities associated with current cytotoxic treatments.

  16. Endophytic Fungi Produce Gibberellins and Indoleacetic Acid and Promotes Host-Plant Growth during Stress

    In-Jung Lee

    2012-09-01

    Full Text Available We isolated and examined two endophytic fungi for their potential to secrete phytohormones viz. gibberellins (GAs and indoleacetic acid (IAA and mitigate abiotic stresses like salinity and drought. The endophytic fungi Phoma glomerata LWL2 and Penicillium sp. LWL3 significantly promoted the shoot and allied growth attributes of GAs-deficient dwarf mutant Waito-C and Dongjin-beyo rice. Analysis of the pure cultures of these endophytic fungi showed biologically active GAs (GA1, GA3, GA4 and GA7 in various quantities. The cultures of P. glomerata and Penicillium sp. also contained IAA. The culture application and endophytic-association with host-cucumber plants significantly increased the plant biomass and related growth parameters under sodium chloride and polyethylene glycol induced salinity and drought stress as compared to control plants. The endophytic symbiosis resulted in significantly higher assimilation of essential nutrients like potassium, calcium and magnesium as compared to control plants during salinity stress. Endophytic-association reduced the sodium toxicity and promoted the host-benefit ratio in cucumber plants as compared to non-inoculated control plants. The symbiotic-association mitigated stress by compromising the activities of reduced glutathione, catalase, peroxidase and polyphenol oxidase. Under stress conditions, the endophyte-infection significantly modulated stress through down-regulated abscisic acid, altered jasmonic acid, and elevated salicylic acid contents as compared to control. In conclusion, the two endophytes significantly reprogrammed the growth of host plants during stress conditions.

  17. Salicylic acid and heat acclimation pretreatment protects Laminaria japonica sporophyte (Phaeophyceae) from heat stress

    Zhou, Bin; Tang, Xuexi; Wang, You

    2010-07-01

    Possible mediatory roles of heat acclimation and salicylic acid in protecting the sporophyte of marine macroalga Laminaria japonica (Phaeophyceae) from heat stress were studied. Heat stress resulted in oxidative injury in the kelp blades. Under heat stress significant accumulation of hydrogen peroxide (H2O2) and malonaldehyde (MDA), a membrane lipid peroxidation product, and a drastic decrease in chlorophyll a content were recorded. Activity of the enzymatic antioxidant system was drastically affected by heat stress. The activity of superoxide dismutase (SOD) was significantly increased while peroxidase (POD), catalase (CAT) and glutathione peroxidase (GPX) were greatly inhibited and, simultaneously, phenylalanine ammonia-lyase was activated while polyphenol oxidase (PPO) was inhibited. Both heat acclimation pretreatment and exogenous application of salicylic acid alleviated oxidative damage in kelp blades. Blades receiving heat acclimation pretreatment and exogenous salicylic acid prior to heat stress exhibited a reduced increase in H2O2 and MDA content, and a lower reduction in chlorophyll a content. Pretreatment with heat acclimation and salicylic acid elevated activities of SOD, POD, CAT, GPX and PPO. Considering these results collectively, we speculate that the inhibition of antioxidant enzymes is a possible cause of the heat-stress-induced oxidative stress in L. japonica, and enhanced thermotolerance may be associated, at least in part, with the elevated activity of the enzymatic antioxidant system.

  18. Listeria monocytogenes Shows Temperature-Dependent and -Independent Responses to Salt Stress, Including Responses That Induce Cross-Protection against Other Stresses

    Bergholz, Teresa M.; Bowen, Barbara; Wiedmann, Martin; Boor, Kathryn J.

    2012-01-01

    The food-borne pathogen Listeria monocytogenes experiences osmotic stress in many habitats, including foods and the gastrointestinal tract of the host. During transmission, L. monocytogenes is likely to experience osmotic stress at different temperatures and may adapt to osmotic stress in a temperature-dependent manner. To understand the impact of temperature on the responses this pathogen uses to adapt to osmotic stress, we assessed genome-wide changes in the L. monocytogenes H7858 transcrip...

  19. Eicosapentaenoic Acid Enhances Heat Stress-Impaired Intestinal Epithelial Barrier Function in Caco-2 Cells

    Guizhen Xiao; Liqun Tang; Fangfang Yuan; Wei Zhu; Shaoheng Zhang; Zhifeng Liu; Yan Geng; Xiaowen Qiu; Yali Zhang; Lei Su

    2013-01-01

    OBJECTIVE: Dysfunction of the intestinal epithelial tight junction (TJ) barrier is known to have an important etiologic role in the pathophysiology of heat stroke. N-3 polyunsaturated fatty acids (PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), play a role in maintaining and protecting the TJ structure and function. This study is aimed at investigating whether n-3 PUFAs could alleviate heat stress-induced dysfunction of intestinal tight junction. METHODS: Human i...

  20. N-3 Polyunsaturated Fatty Acids (PUFAs Reverse the Impact of Early-Life Stress on the Gut Microbiota.

    Matteo M Pusceddu

    Full Text Available Early life stress is a risk factor for many psychiatric disorders ranging from depression to anxiety. Stress, especially during early life, can induce dysbiosis in the gut microbiota, the key modulators of the bidirectional signalling pathways in the gut-brain axis that underline several neurodevelopmental and psychiatric disorders. Despite their critical role in the development and function of the central nervous system, the effect of n-3 polyunsaturated fatty acids (n-3 PUFAs on the regulation of gut-microbiota in early-life stress has not been explored.Here, we show that long-term supplementation of eicosapentaenoic acid (EPA/docosahexaenoic acid (DHA (80% EPA, 20% DHA n-3 PUFAs mixture could restore the disturbed gut-microbiota composition of maternally separated (MS female rats. Sprague-Dawley female rats were subjected to an early-life stress, maternal separation procedure from postnatal days 2 to 12. Non-separated (NS and MS rats were administered saline, EPA/DHA 0.4 g/kg/day or EPA/DHA 1 g/kg/day, respectively. Analysis of the gut microbiota in adult rats revealed that EPA/DHA changes composition in the MS, and to a lesser extent the NS rats, and was associated with attenuation of the corticosterone response to acute stress.In conclusion, EPA/DHA intervention alters the gut microbiota composition of both neurodevelopmentally normal and early-life stressed animals. This study offers insights into the interaction between n-3 PUFAs and gut microbes, which may play an important role in advancing our understanding of disorders of mood and cognitive functioning, such as anxiety and depression.

  1. The ObgE/CgtA GTPase influences the stringent response to amino acid starvation in Escherichia coli

    Persky, Nicole S.; Daniel J Ferullo; Cooper, Deani L.; Moore, Hayley R.; Lovett, Susan T.

    2009-01-01

    The stringent response is important for bacterial survival under stressful conditions, such as amino acid starvation, and is characterized by the accumulation of ppGpp and pppGpp. ObgE (CgtA, YhbZ) is an essential conserved GTPase in Escherichia coli and several observations have implicated the protein in the control of the stringent response. However, consequences of the protein on specific responses to amino acid starvation have not been noted. We show that ObgE binds to ppGpp with biologic...

  2. Acute stress responses: A review and synthesis of ASD, ASR, and CSR.

    Isserlin, Leanna; Zerach, Gadi; Solomon, Zahava

    2008-10-01

    Toward the development of a unifying diagnosis for acute stress responses this article attempts to find a place for combat stress reaction (CSR) within the spectrum of other defined acute stress responses. This article critically compares the diagnostic criteria of acute stress disorder (ASD), acute stress reaction (ASR), and CSR. Prospective studies concerning the predictive value of ASD, ASR, and CSR are reviewed. Questions, recommendations, and implications for clinical practice are raised concerning the completeness of the current acute stress response diagnoses, the heterogeneity of different stressors, the scope of expected outcomes, and the importance of decline in function as an indicator of future psychological, psychiatric, and somatic distress. PMID:19123763

  3. Developmentally related responses of maize catalase genes to salicylic acid.

    L. Guan; Scandalios, J G

    1995-01-01

    The response of the maize catalase genes (Cat1, Cat2, and Cat3) to salicylic acid (SA) was examined at two distinct developmental stages: embryogenesis and germination. A unique, germination-related differential response of each maize catalase gene to various doses of SA was observed. During late embryogenesis, total catalase activity in scutella increased dramatically with 1 mM SA treatment. The accumulation of Cat2 transcript and CAT-2 isozyme protein provided the major contribution to the ...

  4. The lmo0501 gene coding for a putative transcription activator protein in Listeria monocytogenes promotes growth under cold, osmotic and acid stress conditions

    Michel, E.

    2011-01-01

    In L. monocytogenes EGDe, the lmo0501 gene locus encodes a protein similar to the mannitol transcription regulator (MltR) protein in B. subtilis and B. stearothermophilus. In this study we investigated its functional role in L. monocytogenes EGDe cells in view of growth under different stress conditions. Increased lmo0501 gene expression at mRNA level was detected in response to cold, osmotic and organic acid stress exposure. An EGDe Δlmo0501 mutant strain was diminished in gro...

  5. A step towards understanding plant responses to multiple environmental stresses: a genome-wide study.

    Sewelam, Nasser; Oshima, Yoshimi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru

    2014-09-01

    In natural habitats, especially in arid areas, plants are often simultaneously exposed to multiple abiotic stresses, such as salt, osmotic and heat stresses. However, most analyses of gene expression in stress responses examine individual stresses. In this report, we compare gene expression in individual and combined stresses. We show that combined stress treatments with salt, mannitol and heat induce a unique pattern of gene expression that is not a simple merge of the individual stress responses. Under multiple stress conditions, expression of most heat and salt stress-responsive genes increased to levels similar to or higher than those measured in single stress conditions, but osmotic stress-responsive genes increased to lower levels. Genes up-regulated to higher levels under multiple stress condition than single stress conditions include genes for heat shock proteins, heat shock regulators and late embryogenesis abundant proteins (LEAs), which protect other proteins from damage caused by stresses, suggesting their importance in multiple stress condition. Based on this analysis, we identify candidate genes for engineering crop plants tolerant to multiple stresses. PMID:24417440

  6. Phloem small RNAs, nutrient stress responses, and systemic mobility

    Kehr Julia

    2010-04-01

    Full Text Available Abstract Background Nutrient availabilities and needs have to be tightly coordinated between organs to ensure a balance between uptake and consumption for metabolism, growth, and defense reactions. Since plants often have to grow in environments with sub-optimal nutrient availability, a fine tuning is vital. To achieve this, information has to flow cell-to-cell and over long-distance via xylem and phloem. Recently, specific miRNAs emerged as a new type of regulating molecules during stress and nutrient deficiency responses, and miR399 was suggested to be a phloem-mobile long-distance signal involved in the phosphate starvation response. Results We used miRNA microarrays containing all known plant miRNAs and a set of unknown small (s RNAs earlier cloned from Brassica phloem sap 1, to comprehensively analyze the phloem response to nutrient deficiency by removing sulfate, copper or iron, respectively, from the growth medium. We show that phloem sap contains a specific set of sRNAs that is distinct from leaves and roots, and that the phloem also responds specifically to stress. Upon S and Cu deficiencies phloem sap reacts with an increase of the same miRNAs that were earlier characterized in other tissues, while no clear positive response to -Fe was observed. However, -Fe led to a reduction of Cu- and P-responsive miRNAs. We further demonstrate that under nutrient starvation miR399 and miR395 can be translocated through graft unions from wild type scions to rootstocks of the miRNA processing hen1-1 mutant. In contrast, miR171 was not transported. Translocation of miR395 led to a down-regulation of one of its targets in rootstocks, suggesting that this transport is of functional relevance, and that miR395, in addition to the well characterized miR399, could potentially act as a long-distance information transmitter. Conclusions Phloem sap contains a specific set of sRNAs, of which some specifically accumulate in response to nutrient deprivation. From

  7. The Early Endocrine Stress Response in Experimental Subarachnoid Hemorrhage.

    Christoffer Nyberg

    Full Text Available In patients with severe illness, such as aneurysmal subarachnoid hemorrhage (SAH, a physiologic stress response is triggered. This includes activation of the hypothalamic-pituitary-adrenal (HPA axis and the sympathetic nervous system. The aim of this study was to investigate the very early responses of these systems.A porcine animal model of aneurysmal SAH was used. In this model, blood is injected slowly to the basal cisterns above the anterior skull base until the cerebral perfusion pressure is 0 mm Hg. Sampling was done from blood and urine at -10, +15, +75 and +135 minutes from time of induction of SAH. Analyses of adrenocorticotropic hormone (ACTH, cortisol, aldosterone, catecholamines and chromogranin-A were performed.Plasma ACTH, serum cortisol and plasma aldosterone increased in the samples following induction of SAH, and started to decline after 75 minutes. Urine cortisol also increased after SAH. Urine catecholamines and their metabolites were found to increase after SAH. Many samples were however below detection level, not allowing for statistical analysis. Plasma chromogranin-A peaked at 15 minutes after SAH, and thereafter decreased.The endocrine stress response after aneurysmal SAH was found to start within 15 minutes in the HPA axis with early peak values of ACTH, cortisol and aldosterone. The fact that the concentrations of the HPA axis hormones decreased 135 minutes after SAH may suggest that a similar pattern exists in SAH patients, thus making it difficult to catch these early peak values. There were also indications of early activation of the sympathetic nervous system, but the small number of valid samples made interpretation difficult.

  8. Ginsenoside rb1 modulates level of monoamine neurotransmitters in mice frontal cortex and cerebellum in response to immobilization stress.

    Lee, Sang Hee; Hur, Jinyoung; Lee, Eunjoo H; Kim, Sun Yeou

    2012-09-01

    Cerebral monoamines play important roles as neurotransmitters that are associated with various stressful stimuli. Some components such as ginsenosides (triterpenoidal glycosides derived from the Ginseng Radix) may interact with monoamine systems. The aim of this study was to determine whether ginsenoside Rb1 can modulate levels of the monoamines such as dihydroxyphenylalanine (DOPA), dopamine (DA), norepinephrine (NE), epinephrine (EP), 3,4-dihydroxyphenylacetic acid (DOPAC), 5-hydorxytryptamine (5-HT), 5-hydroxindole-3-acetic acid (5-HIAA), and 5-hydroxytryptophan (5-HTP) in mice frontal cortex and cerebellum in response to immobilization stress. Mice were treated with ginsenoside Rb1 (10 mg/kg, oral) before a single 30 min immobilization stress. Acute immobilization stress resulted in elevation of monoamine levels in frontal cortex and cerebellum. Pretreatment with ginsenoside Rb1 attenuated the stress-induced changes in the levels of monoamines in each region. The present findings showed the anti-stress potential of ginsenoside Rb1 in relation to regulation effects on the cerebral monoaminergic systems. Therefore, the ginsenoside Rb1 may be a useful candidate for treating several brain symptoms related with stress. PMID:24009838

  9. Transcriptional profiling in response to terminal drought stress reveals differential responses along the wheat genome

    Ferrari Francesco

    2009-06-01

    Full Text Available Abstract Background Water stress during grain filling has a marked effect on grain yield, leading to a reduced endosperm cell number and thus sink capacity to accumulate dry matter. The bread wheat cultivar Chinese Spring (CS, a Chinese Spring terminal deletion line (CS_5AL-10 and the durum wheat cultivar Creso were subjected to transcriptional profiling after exposure to mild and severe drought stress at the grain filling stage to find evidences of differential stress responses associated to different wheat genome regions. Results The transcriptome analysis of Creso, CS and its deletion line revealed 8,552 non redundant probe sets with different expression levels, mainly due to the comparisons between the two species. The drought treatments modified the expression of 3,056 probe sets. Besides a set of genes showing a similar drought response in Creso and CS, cluster analysis revealed several drought response features that can be associated to the different genomic structure of Creso, CS and CS_5AL-10. Some drought-related genes were expressed at lower level (or not expressed in Creso (which lacks the D genome or in the CS_5AL-10 deletion line compared to CS. The chromosome location of a set of these genes was confirmed by PCR-based mapping on the D genome (or the 5AL-10 region. Many clusters were characterized by different level of expression in Creso, CS and CS_AL-10, suggesting that the different genome organization of the three genotypes may affect plant adaptation to stress. Clusters with similar expression trend were grouped and functional classified to mine the biological mean of their activation or repression. Genes involved in ABA, proline, glycine-betaine and sorbitol pathways were found up-regulated by drought stress. Furthermore, the enhanced expression of a set of transposons and retrotransposons was detected in CS_5AL-10. Conclusion Bread and durum wheat genotypes were characterized by a different physiological reaction to water

  10. Morphokinetic-related response to stress in individually cultured bovine embryos.

    Silva, T; Santos, E C; Annes, K; Soares, C A; Leite, R F; Lima, C B; Milazzotto, M P

    2016-09-15

    The kinetics of in vitro-produced (IVP) bovine embryos is related to embryo viability, metabolism, and epigenetic patterns. Therefore, we believe that embryos with different speeds of development also respond differently to stress. In the present study, we performed global metabolic analysis (matrix-assisted laser desorption ionization time of flight mass spectrometry [MALDI-TOF]) of culture media, characterized apoptotic events (Terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL] and caspase quantitation), and quantified transcript abundance of stress-related gene (real-time quantitative polymerase chain reaction [qRT-PCR]) in IVP bovine embryos with different developmental kinetics to investigate possible markers of stress response. For this purpose, embryos were considered "fast" if they presented four or more cells at 40 hours post insemination (hpi). Embryos presenting two cells at this time were classified as "slow". Evaluations were performed at 40 hpi, 112 hpi, and 186 hpi. Metabolome analysis revealed several metabolites differentially represented between groups at all time points related with energy, lipid and amino acids metabolism, and stress response. There was no difference in TUNEL positive cells between groups in any of the time points analyzed. Nevertheless, at 112 hpi, classified as a critical phase because of the genome activation, the amount of caspase 3 and 7 and total caspase were higher in slow when compared to fast group. Transcript abundance analysis of candidate genes (GRP78, HSP60, SOD1, and MORF4L2) was also different among groups. In conclusion, IVP bovine embryos of different development speeds respond differentially to the environmental stress leading to different metabolome patterns and apoptosis activation throughout the culture. PMID:27298151

  11. The litter-fall characteristics and their response to drought stress in the Masson pins forests damaged by acid rain at Chongqing, China%重庆酸雨区马尾松林凋落物特征及对干旱胁迫的响应

    王轶浩; 王彦辉; 于澎涛; 熊伟; 李振华; 郝佳; 段健

    2013-01-01

    The health condition of forests especially those already damaged in the acid rain region will be increasingly influenced by the increasing extreme drought events caused by climate change.Understanding the forest health response to multiple stresses is a new challenge.The characteristics of litter-fall can be used as an important indicator to reflect forest health condition and its response to environmental stresses.The aim of this study is to detect how drought stress affect the litter-fall characteristics of forests for a better understanding and more precise prediction of the forest health decline in the acid rain region of south China.Masson pine (Pinus massoniana) is a native and widely distributed tree species in south China, it is also one of the most important tree species used for forestation and widely damaged by acid rain.The litter-fall quantity and its components ( dead needles, green needles, twigs, debris, bark and cones, and broad leaves of other tree species) in the Masson pine forest stands were monitored at Tieshanping of Chongqing in 2010, and their responses to soil moisture was analyzed through Pearson correlation.The results showed that the monthly variation of litter-fall presented a "two-peak" pattern.The highest peak appeared in the dry-summer period of August-September with the lowest soil moisture and amounted to 2.30 t/hm2 ; the second peak appeared during the dormancy period of December and was only 0.65 t/ hm ; the amount of litter-fall in the two peak periods accounted for 49.56% of the annual total (5.96 t/hm ) in 2010.The annual dead needle was 2.89 t/hm ; it accounted for 48.42% of the annual total of litter-fall.The order of weight percentage of the litter-fall components was; needles > twigs > broad leaves > debris > bark and cones.The variation of monthly dead needle amount well presented the variation of total litter-fall amount.The monthly proportion of dead needle to total litter-fall was almost the highest in the whole year

  12. Feedbacks and tipping points in organismal response to oxidative stress.

    Klanjscek, Tin; Muller, Erik B; Nisbet, Roger M

    2016-09-01

    Biological feedbacks play a crucial role in determining effects of toxicants, radiation, and other environmental stressors on organisms. Focusing on reactive oxygen species (ROS) that are increasingly recognized as a crucial mediator of many stressor effects, we investigate how feedback strength affects the ability of organisms to control negative effects of exposure. We do this by developing a general theoretical framework for describing effects of a wide range of stressors and species. The framework accounts for positive and negative feedbacks representing cellular processes: (i) production of ROS due to metabolism and the stressor, (ii) ROS reactions with cellular compounds that cause damage, and (iii) cellular control of both ROS and damage. We suggest functional forms that capture generic properties of cellular control mechanisms constituting the feedbacks, assess stability of equilibrium states in the resulting models, and investigate tipping points at which cellular control breaks down causing unregulated increase of ROS and damage. Depending on the chosen functional forms, the models can have zero, one, or two positive steady states; except in one singular case, the steady state with lowest values of ROS and damage is locally stable. We found two types of tipping points: those induced by changes in the parameters (including the stressor intensity), and those induced by the history of exposure, i.e. ROS and damage levels. The relatively simple models effectively describe several patterns of cellular responses to stress, such as the covariation of ROS and damage, the break-down of cellular control leading to explosion of ROS and/or damage, increase in damage even when ROS is (near)-constant, and the effects of exposure history on the ability of the cell to handle additional stress. The models quantify dynamics of cellular control, and could therefore be used to estimate the metabolic costs of stress and help integrate them into models that use energetic

  13. Jasmonates: signal transduction components and their roles in environmental stress responses.

    Goossens, Jonas; Fernández-Calvo, Patricia; Schweizer, Fabian; Goossens, Alain

    2016-08-01

    Jasmonates, oxylipin-type plant hormones, are implicated in diverse aspects of plant growth development and interaction with the environment. Following diverse developmental and environmental cues, jasmonate is produced, conjugated to the amino acid isoleucine and perceived by a co-receptor complex composed of the Jasmonate ZIM-domain (JAZ) repressor proteins and an E3 ubiquitin ligase complex containing the F-box CORONATINE INSENSITIVE 1 (COI1). This event triggers the degradation of the JAZ proteins and the release of numerous transcription factors, including MYC2 and its homologues, which are otherwise bound and inhibited by the JAZ repressors. Here, we will review the role of the COI1, JAZ and MYC2 proteins in the interaction of the plant with its environment, illustrating the significance of jasmonate signalling, and of the proteins involved, for responses to both biotic stresses caused by insects and numerous microbial pathogens and abiotic stresses caused by adverse climatic conditions. It has also become evident that crosstalk with other hormone signals, as well as light and clock signals, plays an important role in the control and fine-tuning of these stress responses. Finally, we will discuss how several pathogens exploit the jasmonate perception and early signalling machinery to decoy the plants defence systems. PMID:27086135

  14. Z α-1 antitrypsin deficiency and the endoplasmic reticulum stress response

    Catherine; M; Greene; Noel; G; McElvaney

    2010-01-01

    The serine proteinase inhibitor α-1 antitrypsin(AAT) is produced principally by the liver at the rate of 2 g/d.It is secreted into the circulation and provides an antiprotease protective screen throughout the body but most importantly in the lung,where it can neutralise the activity of the serine protease neutrophil elastase.Mutations leading to def iciency in AAT are associated with liver and lung disease.The most notable is the Z AAT mutation,which encodes a misfolded variant of the AAT protein in which the glutamic acid at position 342 is replaced by a lysine.More than 95% of all individuals with AAT def iciency carry at least one Z allele.ZAAT protein is not secreted effectively and accumulates intracellularly in the endoplasmic reticulum(ER) of hepatocytes and other AAT-producing cells.This results in a loss of function associated with decreased circulating and intrapulmonary levels of AAT.However,the misfolded protein acquires a toxic gain of function that impacts on the ER.A major function of the ER is to ensure correct protein folding.ZAAT interferes with this function and promotes ER stress responses and inflammation.Here the signalling pathways activated during ER stress in response to accumulation of ZAAT are described and therapeutic strategies that can potentially relieve ER stress are discussed.

  15. Subcellular proteomic characterization of the high-temperature stress response of the cyanobacterium Spirulina platensis

    Cheevadhanarak Supapon

    2009-09-01

    Full Text Available Abstract The present study examined the changes in protein expression in Spirulina platensis upon exposure to high temperature, with the changes in expression analyzed at the subcellular level. In addition, the transcriptional expression level of some differentially expressed proteins, the expression pattern clustering, and the protein-protein interaction network were analyzed. The results obtained from differential expression analysis revealed up-regulation of proteins involved in two-component response systems, DNA damage and repair systems, molecular chaperones, known stress-related proteins, and proteins involved in other biological processes, such as capsule formation and unsaturated fatty acid biosynthesis. The clustering of all differentially expressed proteins in the three cellular compartments showed: (i the majority of the proteins in all fractions were sustained tolerance proteins, suggesting the roles of these proteins in the tolerance to high temperature stress, (ii the level of resistance proteins in the photosynthetic membrane was 2-fold higher than the level in two other fractions, correlating with the rapid inactivation of the photosynthetic system in response to high temperature. Subcellular communication among the three cellular compartments via protein-protein interactions was clearly shown by the PPI network analysis. Furthermore, this analysis also showed a connection between temperature stress and nitrogen and ammonia assimilation.

  16. Z α-1 antitrypsin deficiency and the endoplasmic reticulum stress response.

    Greene, Catherine M

    2010-10-06

    The serine proteinase inhibitor α-1 antitrypsin (AAT) is produced principally by the liver at the rate of 2 g\\/d. It is secreted into the circulation and provides an antiprotease protective screen throughout the body but most importantly in the lung, where it can neutralise the activity of the serine protease neutrophil elastase. Mutations leading to deficiency in AAT are associated with liver and lung disease. The most notable is the Z AAT mutation, which encodes a misfolded variant of the AAT protein in which the glutamic acid at position 342 is replaced by a lysine. More than 95% of all individuals with AAT deficiency carry at least one Z allele. ZAAT protein is not secreted effectively and accumulates intracellularly in the endoplasmic reticulum (ER) of hepatocytes and other AAT-producing cells. This results in a loss of function associated with decreased circulating and intrapulmonary levels of AAT. However, the misfolded protein acquires a toxic gain of function that impacts on the ER. A major function of the ER is to ensure correct protein folding. ZAAT interferes with this function and promotes ER stress responses and inflammation. Here the signalling pathways activated during ER stress in response to accumulation of ZAAT are described and therapeutic strategies that can potentially relieve ER stress are discussed.

  17. Arabidopsis non-specific phospholipase C1: Characterisation and its involvement in response to heat stress

    Zuzana eKrčková

    2015-11-01

    Full Text Available The Arabidopsis non-specific phospholipase C (NPC protein family is encoded by the genes NPC1 – NPC6. It has been shown that NPC4 and NPC5 possess phospholipase C activity; NPC3 has lysophosphatidic acid phosphatase activity. NPC3, 4 and 5 play roles in the responses to hormones and abiotic stresses. NPC1, 2 and 6 has not been studied functionally yet.We found that Arabidopsis NPC1 expressed in E. coli possesses phospholipase C activity in vitro. This protein was able to hydrolyse phosphatidylcholine to diacylglycerol. NPC1-green fluorescent protein was localized to secretory pathway compartments in Arabidopsis roots. In the knock out T-DNA insertion line NPC1 (npc1 basal thermotolerance was impaired compared with wild-type; npc1 exhibited significant decreases in survival rate and chlorophyll content at the seventh day after heat stress. Conversely, plants overexpressing NPC1 (NPC1-OE were more resistant to heat stress compared with wild-type. These findings suggest that NPC1 is involved in the plant response to heat

  18. Infants, Mothers, and Dyadic Contributions to Stability and Prediction of Social Stress Response at 6 Months

    Provenzi, Livio; Olson, Karen L.; Montirosso, Rosario; Tronick, Ed

    2016-01-01

    The study of infants' interactive style and social stress response to repeated stress exposures is of great interest for developmental and clinical psychologists. Stable maternal and dyadic behavior is critical to sustain infants' development of an adaptive social stress response, but the association between infants' interactive style and social…

  19. Integrin-like Protein Is Involved in the Osmotic Stress-induced Abscisic Acid Biosynthesis in Arabidopsis thaliana

    Bing Lü; Feng Chen; Zhong-Hua Gong; Hong Xie; Jian-Sheng Liang

    2007-01-01

    We studied the perception of plant cells to osmotic stress that leads to the accumulation of abscisic acid (ABA) in stressed Arabidopsis thaliana L. cells. A significant difference was found between protoplasts and cells in terms of their responses to osmotic stress and ABA biosynthesis, implying that cell wall and/or cell wall-plasma membrane interaction are essential in identifying osmotic stress. Western blotting and immunofluorescence localization experiments, using polyclonal antibody against human integrin β1, revealed the existence of a protein similar to the integrin protein of animals in the suspension-cultured cells located in the plasma membrane fraction.Treatment with a synthetic pentapeptide, Gly-Arg-Gly-Asp-Ser (GRGDS), which contains an RGD domain and interacts specifically with integrin protein and thus blocks the cell wall-plasma membrane interaction, significantly inhibited osmotic stress-induced ABA biosynthesis in cells, but not in protoplasts. These results demonstrate that cell wall and/or cell wall-plasma membrane interaction mediated by integrin-like proteins played important roles in osmotic stress-induced ABA biosynthesis in Arabidopsis thaliana.

  20. The effect of acid rain stress on chlorophyll, peroxidase of the conservation of rare earth elements

    Full text: Based on pot experiment, the effect of acid rain stress on chlorophyll, peroxidase of wheat, the relationship of them and the conservation of rare earth elements has been studied. The result showed: stress of acid rain resulted in decrease of chlorophyll content and a/b values, chlorophyll a/b value and chlorophyll content is positive correlation with pH value of acid rain: peroxidase activity was gradually rise with pH value decrease, which indirectly increased decomposition intensity of chlorophyll. Decreased content and a/b value of chlorophyll further speeded blade decay affected the transport and transformation of light energy and metabolism of carbohydrates. After being treated by rare earth elements content and pH value of chlorophyll and peroxidase activity could be relatively stable. Therefore, under lower acidity condition, rare earth elements can influence the effect of acid rain on chlorophyll and peroxidase activity of wheat

  1. Transcriptional and antioxidative responses to endogenous polyunsaturated fatty acid accumulation in yeast.

    Andrisic, Luka; Collinson, Emma J; Tehlivets, Oksana; Perak, Eleonora; Zarkovic, Tomislav; Dawes, Ian W; Zarkovic, Neven; Cipak Gasparovic, Ana

    2015-01-01

    Pathophysiology of polyunsaturated fatty acids (PUFAs) is associated with aberrant lipid and oxygen metabolism. In particular, under oxidative stress, PUFAs are prone to autocatalytic degradation via peroxidation, leading to formation of reactive aldehydes with numerous potentially harmful effects. However, the pathological and compensatory mechanisms induced by lipid peroxidation are very complex and not sufficiently understood. In our study, we have used yeast capable of endogenous PUFA synthesis in order to understand the effects triggered by PUFA accumulation on cellular physiology of a eukaryotic organism. The mechanisms induced by PUFA accumulation in S. cerevisiae expressing Hevea brasiliensis Δ12-fatty acid desaturase include down-regulation of components of electron transport chain in mitochondria as well as up-regulation of pentose-phosphate pathway and fatty acid β-oxidation at the transcriptional level. Interestingly, while no changes were observed at the transcriptional level, activities of two important enzymatic antioxidants, catalase and glutathione-S-transferase, were altered in response to PUFA accumulation. Increased intracellular glutathione levels further suggest an endogenous oxidative stress and activation of antioxidative defense mechanisms under conditions of PUFA accumulation. Finally, our data suggest that PUFA in cell membrane causes metabolic changes which in turn lead to adaptation to endogenous oxidative stress. PMID:25280400

  2. Effect of Salicylic Acid on the Growth and Physiological Characteristics of Maize under Stress Conditions

    Salicylic acid (SA) is a naturally occurring signaling molecule and growth regulator that enhances plant growth particularly in stress conditions. The present study was planned to evaluate the effects of different levels of SA on maize growth under drought and salt stress conditions. An experiment was conducted to test the morphological, physiological and biochemical changes in two cultivar of maize D-1184 and TG-8250. Varying levels of salicylic acid, i.e. 5mM, 10mM and 15mM were applied through foliar method. Exogenous applications of salicylic acid were done after 20 days of germination of the maize plants. Salicylic acid significantly affects root and shoot dry matter under drought and salt stress. Foliar application of SA significantly increased proline concentration (11 percentage and 12 percentage), amino acid accumulation (25 percentage and 18 percentage), relative water (17 percentage and 14 percentage) and Chlorophyll content. Overall, it can be concluded that SA at lower concentration is effective to minimize the effect of stress conditions. Maize cultivar TG-8250 showed better tolerance under drought and salt stress condition as compared to D-1184 cultivar. (author)

  3. Evolution of physiological responses to salt stress in hexaploid wheat.

    Yang, Chunwu; Zhao, Long; Zhang, Huakun; Yang, Zongze; Wang, Huan; Wen, Shanshan; Zhang, Chunyu; Rustgi, Sachin; von Wettstein, Diter; Liu, Bao

    2014-08-12

    Hexaploid bread wheat (Triticum aestivum L., genome BBAADD) is generally more salt tolerant than its tetraploid wheat progenitor (Triticum turgidum L.). However, little is known about the physiological basis of this trait or about the relative contributions of allohexaploidization and subsequent evolutionary genetic changes on the trait development. Here, we compared the salt tolerance of a synthetic allohexaploid wheat (neo-6x) with its tetraploid (T. turgidum; BBAA) and diploid (Aegilops tauschii; DD) parents, as well as a natural hexaploid bread wheat (nat-6x). We studied 92 morphophysiological traits and analyzed homeologous gene expression of a major salt-tolerance gene High-Affinity K(+) Transporter 1;5 (HKT1;5). We observed that under salt stress, neo-6x exhibited higher fitness than both of its parental genotypes due to inheritance of favorable traits like higher germination rate from the 4x parent and the stronger root Na(+) retention capacity from the 2x parent. Moreover, expression of the D-subgenome HKT1;5 homeolog, which is responsible for Na(+) removal from the xylem vessels, showed an immediate transcriptional reprogramming following allohexaploidization, i.e., from constitutive high basal expression in Ae. tauschii (2x) to salt-induced expression in neo-6x. This phenomenon was also witnessed in the nat-6x. An integrated analysis of 92 traits showed that, under salt-stress conditions, neo-6x resembled more closely the 2x than the 4x parent, suggesting that the salt stress induces enhanced expressivity of the D-subgenome homeologs in the synthetic hexaploid wheat. Collectively, the results suggest that condition-dependent functionalization of the subgenomes might have contributed to the wide-ranging adaptability of natural hexaploid wheat. PMID:25074914

  4. Differential stress reaction of human colon cells to oleic-acid-stabilized and unstabilized ultrasmall iron oxide nanoparticles

    Schütz CA

    2014-07-01

    Full Text Available Catherine A Schütz,1,* Davide Staedler,2,* Kieran Crosbie-Staunton,3 Dania Movia,4 Catherine Chapuis Bernasconi,1 Blanka Halamoda Kenzaoui,1 Adriele Prina-Mello,3,4 Lucienne Juillerat-Jeanneret11Centre Hospitalier Universitaire Vaudois (CHUV, UNIL, 2Institute of Chemical Sciences and Engineering, EPFL, CH-1015, Lausanne, Switzerland; 3School of Medicine, 4CRANN, Trinity College Dublin, Dublin, Ireland*These authors contributed equally to this workAbstract: Therapeutic engineered nanoparticles (NPs, including ultrasmall superparamagnetic iron oxide (USPIO NPs, may accumulate in the lower digestive tract following ingestion or injection. In order to evaluate the reaction of human colon cells to USPIO NPs, the effects of non-stabilized USPIO NPs (NS-USPIO NPs, oleic-acid-stabilized USPIO NPs (OA-USPIO NPs, and free oleic acid (OA were compared in human HT29 and CaCo2 colon epithelial cancer cells. First the biophysical characteristics of NS-USPIO NPs and OA-USPIO NPs in water, in cell culture medium supplemented with fetal calf serum, and in cell culture medium preconditioned by HT29 and CaCo2 cells were determined. Then, stress responses of the cells were evaluated following exposure to NS-USPIO NPs, OA-USPIO NPs, and free OA. No modification of the cytoskeletal actin network was observed. Cell response to stress, including markers of apoptosis and DNA repair, oxidative stress and degradative/autophagic stress, induction of heat shock protein, or lipid metabolism was determined in cells exposed to the two NPs. Induction of an autophagic response was observed in the two cell lines for both NPs but not free OA, while the other stress responses were cell- and NP-specific. The formation of lipid vacuoles/droplets was demonstrated in HT29 and CaCo2 cells exposed to OA-USPIO NPs but not to NS-USPIO NPs, and to a much lower level in cells exposed to equimolar concentrations of free OA. Therefore, the induction of lipid vacuoles in colon cells

  5. [Physiological responses of Gracilaria lemaneiformis to copper stress].

    Zhu, Xi-Feng; Zou, Ding-Hui; Jian, Jian-Bo; Chen, Wei-Zhou; Liu, Hui-Hui; Du, Hong

    2009-06-01

    Gracilaria lemaneiformis was exposed to 0, 25, 50, 100, 250 and 500 microg x L(-1) of Cu2+ to study its physiological responses to Cu2+ stress. When the Cu2+ concentration was > or = 50 microg x L(-1), the relative growth rate (RGR) of G. lemaneiformis decreased significantly, and the optimal quantum yield (Fv/Fm), the maximum relative electron transfer rate (rETRmax), and the relative electron transfer efficiency (alpha) exhibited the same variation trend, compared with the control. With the increase of Cu2+ concentration, the maximum net photosynthetic rate (Pmax) and light saturation point (LSP) decreased significantly, light compensation point (LCP) had a significant increase, while chlorophyll a, carotenoid, and phycobiliprotein contents decreased after an initial increase. When the Cu2+ concentration reached 500 microg x L(-1), the chlorophyll a, carotenoid, and phycobiliprotein contents decreased significantly. It was suggested that G. lemaneiformis could tolerate low concentration Cu2+ stress, but its physiological activities were inhibited markedly when exposed to > or =50 microg x L(-1) of Cu2+. PMID:19795656

  6. Sexual Dimorphism in the Response of Mercurialis annua to Stress

    Ezra M. Orlofsky

    2016-04-01

    Full Text Available The research presented stemmed from the observations that female plants of the annual dioecious Mercurialis annua outlive male plants. This led to the hypothesis that female plants of M. annua would be more tolerant to stress than male plants. This hypothesis was addressed in a comprehensive way, by comparing morphological, biochemical and metabolomics changes in female and male plants during their development and under salinity. There were practically no differences between the genders in vegetative development and physiological parameters. However, under salinity conditions, female plants produced significantly more new reproductive nodes. Gender-linked differences in peroxidase (POD and glutathione transferases (GSTs were involved in anti-oxidation, detoxification and developmental processes in M. annua. 1H NMR metabolite profiling of female and male M. annua plants showed that under salinity the activity of the TCA cycle increased. There was also an increase in betaine in both genders, which may be explainable by its osmo-compatible function under salinity. The concentration of ten metabolites changed in both genders, while ‘Female-only-response’ to salinity was detected for five metabolites. In conclusion, dimorphic responses of M. annua plant genders to stress may be attributed to female plants’ capacity to survive and complete the reproductive life cycle.

  7. 2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010

    Sarah Ades

    2011-07-23

    The 2010 Gordon Research Conference on Microbial Stress Responses provides an open and exciting forum for the exchange of scientific discoveries on the remarkable mechanisms used by microbes to survive in nearly every niche on the planet. Understanding these stress responses is critical for our ability to control microbial survival, whether in the context of biotechnology, ecology, or pathogenesis. From its inception in 1994, this conference has traditionally employed a very broad definition of stress in microbial systems. Sessions will cover the major steps of stress responses from signal sensing to transcriptional regulation to the effectors that mediate responses. A wide range of stresses will be represented. Some examples include (but are not limited to) oxidative stress, protein quality control, antibiotic-induced stress and survival, envelope stress, DNA damage, and nutritional stress. The 2010 meeting will also focus on the role of stress responses in microbial communities, applied and environmental microbiology, and microbial development. This conference brings together researchers from both the biological and physical sciences investigating stress responses in medically- and environmentally relevant microbes, as well as model organisms, using cutting-edge techniques. Computational, systems-level, and biophysical approaches to exploring stress responsive circuits will be integrated throughout the sessions alongside the more traditional molecular, physiological, and genetic approaches. The broad range of excellent speakers and topics, together with the intimate and pleasant setting at Mount Holyoke College, provide a fertile ground for the exchange of new ideas and approaches.

  8. An Efficient Chronic Unpredictable Stress Protocol to Induce Stress-Related Responses in C57BL/6 Mice

    Monteiro, Susana; Roque, Susana; de Sá-Calçada, Daniela; Sousa, Nuno; Correia-Neves, Margarida; Cerqueira, João José

    2015-01-01

    Exposure to chronic stress can have broad effects on health ranging from increased predisposition for neuropsychiatric disorders to deregulation of immune responses. The chronic unpredictable stress (CUS) protocol has been widely used to study the impact of stress exposure in several animal models and consists in the random, intermittent, and unpredictable exposure to a variety of stressors during several weeks. CUS has consistently been shown to induce behavioral and immunological alteration...

  9. A Stress-Coping Model of Mental Illness Stigma: II. Emotional Stress Responses, Coping Behavior and Outcome

    Rüsch, Nicolas; Corrigan, Patrick W.; Powell, Karina; Rajah, Anita; Olschewski, Manfred; Wilkniss, Sandra; Batia, Karen

    2009-01-01

    Stigma can be a major stressor for people with schizophrenia and other mental illnesses, leading to emotional stress reactions and cognitive coping responses. Stigma is appraised as a stressor if perceived stigma-related harm exceeds an individual’s perceived coping resources. It is unclear, however, how people with mental illness react to stigma stress and how that affects outcomes such as self-esteem, hopelessness and social performance. The cognitive appraisal of stigma stress as well as e...

  10. Molecular physiology of weak organic acid stress in Bacillus subtilis

    Brul, S.; Beilen, van, J.W.A.

    2013-01-01

    The mechanism by which weak organic acid (WOA) preservatives inhibit growth of microorganisms may differ between different WOAs and these differences are not well understood. The aim of this thesis has been to obtain a better understanding of the mode of action of these preservatives by which they inhibit the growth of spore-forming bacteria (more specifically Bacillus subtilis).

  11. Regulation of abiotic and biotic stress responses by plant hormones

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

    2016-01-01

    Plant hormones (phytohormones) are signal molecules produced within the plant, and occur in very low concentrations. In the present chapter, the current knowledge on the regulation of biotic and biotic stress responses by plant hormones is summarized with special focus on the novel insights into...... the complex hormonal crosstalk of classical growth stimulating plant hormones within the naturally occurring biotic and abiotic multistress environment of higher plants. The MAPK- and phytohormone-cascades which comprise a multitude of single molecules on different signalling levels, as well as...... interactions and cross-regulations within and between these signalling pathways allow very specific and fine-tuned modulation of plant immunity. The endoplasmic reticulum (ER)-associated protein degradation system (ERAD) is a quality control system that degrades improperly folded proteins from the secretory...

  12. Response of spermatozoa to hyposmotic stress reflects cryopreservation success

    Watson, P.F.; Curry, M.R. (Royal Veterinary College, Dept. of Veterinary Basic Sciences, London (UK)); Noiles, E.E.; Critser, J.K. (Methodist Hospital of Indiana, Inc., Indianapolis, IN (United States). Center for Reproduction); Mazur, P. (Oak Ridge National Lab., TN (United States)); Hammerstedt, R.H. (Pennsylvania State Univ., University Park, PA (United States). Dept. of Cellular and Molecular B

    1992-01-01

    Spermatozoa of several species were washed and then subjected to dilution in hyposmotic Tyrode's based solutions. The cells were stained with fluorescent viability stains, carboxyfluorescein diacetate and propidium iodide, and proportions with intact plasma membranes determined by flow cytometry or fluorescence microscopy. Fowl spermatozoa remained almost 100% intact until very low osmolality, and then ruptured. Human spermatozoa showed a similar response with only a small decrease in intact cells before the precipitous decline at low osmolality. Bull spermatozoa were more readily disrupted at higher osmolality, some 40% being damaged before the sudden decline at low osmolality. Ram and boar spermatozoa were progressively disrupted even at mild hyposmotic stress, showing approximately 50% of cells ruptured at 150 mOsm.

  13. Response of spermatozoa to hyposmotic stress reflects cryopreservation success

    Watson, P.F.; Curry, M.R. [Royal Veterinary College, Dept. of Veterinary Basic Sciences, London (UK); Noiles, E.E.; Critser, J.K. [Methodist Hospital of Indiana, Inc., Indianapolis, IN (United States). Center for Reproduction; Mazur, P. [Oak Ridge National Lab., TN (United States); Hammerstedt, R.H. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Cellular and Molecular Biochemistry

    1992-06-01

    Spermatozoa of several species were washed and then subjected to dilution in hyposmotic Tyrode`s based solutions. The cells were stained with fluorescent viability stains, carboxyfluorescein diacetate and propidium iodide, and proportions with intact plasma membranes determined by flow cytometry or fluorescence microscopy. Fowl spermatozoa remained almost 100% intact until very low osmolality, and then ruptured. Human spermatozoa showed a similar response with only a small decrease in intact cells before the precipitous decline at low osmolality. Bull spermatozoa were more readily disrupted at higher osmolality, some 40% being damaged before the sudden decline at low osmolality. Ram and boar spermatozoa were progressively disrupted even at mild hyposmotic stress, showing approximately 50% of cells ruptured at 150 mOsm.

  14. Foliar abscisic acid-to-ethylene accumulation and response regulate shoot growth sensitivity to mild drought in wheat

    Valluru, Ravi; Davies, William John; Reynolds, Matthew; Dodd, Ian Charles

    2016-01-01

    Although, plant hormones play an important role in adjusting growth in response to environmental perturbation, the relative contributions of abscisic acid (ABA) and ethylene remain elusive. Using six spring wheat genotypes differing for stress tolerance, we show that young seedlings of the drought-tolerant (DT) group maintained or increased shoot dry weight (SDW) while the drought-susceptible (DS) group decreased SDW in response to mild drought. Both the DT and DS groups increased endogenous ...

  15. Foliar abscisic acid-to-ethylene accumulation and response regulate shoot growth sensitivity to mild drought in wheat

    Ravi eValluru; William J eDavies; Matthew P eReynolds; Ian C eDodd

    2016-01-01

    Although plant hormones play an important role in adjusting growth in response to environmental perturbation, the relative contributions of abscisic acid (ABA) and ethylene remain elusive. Using six spring wheat genotypes differing for stress tolerance, we show that young seedlings of the drought-tolerant (DT) group maintained or increased shoot dry weight (SDW) while the drought-susceptible (DS) group decreased SDW in response to mild drought. Both the DT and DS groups increased endogenous A...

  16. Abscisic acid and stress signals induce Viviparous1 expression in seed and vegetative tissues of maize.

    Cao, Xueyuan; Costa, Liliana M; Biderre-Petit, Corinne; Kbhaya, Bouchab; Dey, Nrisingha; Perez, Pascual; McCarty, Donald R; Gutierrez-Marcos, Jose F; Becraft, Philip W

    2007-02-01

    Viviparous1 (Vp1) encodes a B3 domain-containing transcription factor that is a key regulator of seed maturation in maize (Zea mays). However, the mechanisms of Vp1 regulation are not well understood. To examine physiological factors that may regulate Vp1 expression, transcript levels were monitored in maturing embryos placed in culture under different conditions. Expression of Vp1 decreased after culture in hormone-free medium, but was induced by salinity or osmotic stress. Application of exogenous abscisic acid (ABA) also induced transcript levels within 1 h in a dose-dependent manner. The Vp1 promoter fused to beta-glucuronidase or green fluorescent protein reproduced the endogenous Vp1 expression patterns in transgenic maize plants and also revealed previously unknown expression domains of Vp1. The Vp1 promoter is active in the embryo and aleurone cells of developing seeds and, upon drought stress, was also found in phloem cells of vegetative tissues, including cobs, leaves, and stems. Sequence analysis of the Vp1 promoter identified a potential ABA-responsive complex, consisting of an ACGT-containing ABA response element (ABRE) and a coupling element 1-like motif. Electrophoretic mobility shift assay confirmed that the ABRE and putative coupling element 1 components specifically bound proteins in embryo nuclear protein extracts. Treatment of embryos in hormone-free Murashige and Skoog medium blocked the ABRE-protein interaction, whereas exogenous ABA or mannitol treatment restored this interaction. Our data support a model for a VP1-dependent positive feedback mechanism regulating Vp1 expression during seed maturation. PMID:17208960

  17. Oxidative stress response of Inonotus obliquus induced by hydrogen peroxide.

    Zheng, Weifa; Zhao, Yanxia; Zhang, Meimei; Wei, Zhiwen; Miao, Kangjie; Sun, Weiguo

    2009-12-01

    While the medicinal fungus Inonotus obliquus produces polyphenols as one of its main metabolites in natural habitats, it accumulates less polyphenols under laboratory conditions. In this study we found that the continuous addition of 1 mM H(2)O(2) at a rate of 1.6 ml/h into a submerged culture of the fungus enhanced its production of mycelia, melanins, flavonoids and hispidin analogs (HA). Simultaneous exposure of the fungus to both H(2)O(2) and arbutin resulted in reduced production of mycelia, glycosylated flavonoids (GF) and HA, and inhibition of melanogenesis. However, superoxide dismutases (SOD) and catalase (CAT) activity were enhanced following the addition of H(2)O(2) or H(2)O(2) plus arbutin. The maximum levels of SOD and CAT activities reached 355.2 U/mg protein and 39.8 U/mg protein respectively in H(2)O(2)-added medium, and 264 U/mg protein and 35.9 U/mg protein respectively in H(2)O(2) plus arbutin medium. Thus, detoxification of H(2)O(2) is conducted mainly by polyphenols under normal physiological conditions, and by both polyphenols and antioxidant enzymes under oxidative stress when melanogenesis is inhibited. Although enhanced HA production occurred after melanogenesis inactivation, total extracellular polyphenol levels were reduced. These findings suggest that enzymatic activities convert superoxide to H(2)O(2), and non-enzymatic mechanisms are largely responsible for detoxifying H(2)O(2). Enhanced production of melanins is the most important non-enzymatic response of this fungus against oxidative stress. PMID:19184774

  18. Saccharomyces cerevisiae Tti2 Regulates PIKK Proteins and Stress Response

    Hoffman, Kyle S.; Duennwald, Martin L.; Karagiannis, Jim; Genereaux, Julie; McCarton, Alexander S.; Brandl, Christopher J.

    2016-01-01

    The TTT complex is composed of the three essential proteins Tel2, Tti1, and Tti2. The complex is required to maintain steady state levels of phosphatidylinositol 3-kinase-related kinase (PIKK) proteins, including mTOR, ATM/Tel1, ATR/Mec1, and TRRAP/Tra1, all of which serve as regulators of critical cell signaling pathways. Due to their association with heat shock proteins, and with newly synthesized PIKK peptides, components of the TTT complex may act as cochaperones. Here, we analyze the consequences of depleting the cellular level of Tti2 in Saccharomyces cerevisiae. We show that yeast expressing low levels of Tti2 are viable under optimal growth conditions, but the cells are sensitive to a number of stress conditions that involve PIKK pathways. In agreement with this, depleting Tti2 levels decreased expression of Tra1, Mec1, and Tor1, affected their localization and inhibited the stress responses in which these molecules are involved. Tti2 expression was not increased during heat shock, implying that it does not play a general role in the heat shock response. However, steady state levels of Hsp42 increase when Tti2 is depleted, and tti2L187P has a synthetic interaction with exon 1 of the human Huntingtin gene containing a 103 residue polyQ sequence, suggesting a general role in protein quality control. We also find that overexpressing Hsp90 or its cochaperones is synthetic lethal when Tti2 is depleted, an effect possibly due to imbalanced stoichiometry of a complex required for PIKK assembly. These results indicate that Tti2 does not act as a general chaperone, but may have a specialized function in PIKK folding and/or complex assembly. PMID:27172216

  19. Pre-sowing application of ascorbic acid and salicylic acid to seed of pumpkin and seedling response to salt

    The effects of seed soaking with salicylic acid or ascorbic acid on pumpkin seedlings growth under saline (10 dS m/sup -1/) conditions were investigated. Seedlings fresh weight, protein contents, protease and nitrate reductase activities were significantly affected by 15 and 30 mg L/sup -1/ salicylic acid and 30 mg L/sup -1/ ascorbic acid priming treatments, under both normal and saline conditions. Priming reduced the severity of the salt stress, the amelioration was better due to 30 mg L/sup -1/ ascorbic acid or 30 mg L/sup -1/ salicylic acid treatments as these treatments showed best results on seedling growth, fresh and dry matter production under non-saline and saline environments. Application of seed priming with ascorbic acid and salicylic acid in pumpkin ameliorate the adverse effects of salt stress. (author)

  20. Opioid partial agonist buprenorphine dampens responses to psychosocial stress in humans

    Bershad, Anya K.; Jaffe, Jerome H.; Childs, Emma; de Wit, Harriet

    2014-01-01

    Preclinical and clinical evidence indicates that opioid drugs have stress-dampening effects. In animal models, opioid analgesics attenuate responses to isolation distress, and in humans, opioids reduce stress related to anticipation of physical pain. The stress-reducing effects of opioid drugs may contribute to their abuse potential. Despite this evidence in laboratory animals, the effects of opioids on responses to psychosocial stress have not been determined in humans. Here we examined the ...