WorldWideScience

Sample records for biotic stress response

  1. Regulation of abiotic and biotic stress responses by plant hormones

    DEFF Research Database (Denmark)

    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...

  2. The Role of Tomato WRKY Genes in Plant Responses to Combined Abiotic and Biotic Stresses

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    Yuling Bai

    2018-06-01

    Full Text Available In the field, plants constantly face a plethora of abiotic and biotic stresses that can impart detrimental effects on plants. In response to multiple stresses, plants can rapidly reprogram their transcriptome through a tightly regulated and highly dynamic regulatory network where WRKY transcription factors can act as activators or repressors. WRKY transcription factors have diverse biological functions in plants, but most notably are key players in plant responses to biotic and abiotic stresses. In tomato there are 83 WRKY genes identified. Here we review recent progress on functions of these tomato WRKY genes and their homologs in other plant species, such as Arabidopsis and rice, with a special focus on their involvement in responses to abiotic and biotic stresses. In particular, we highlight WRKY genes that play a role in plant responses to a combination of abiotic and biotic stresses.

  3. Identification of Arabidopsis candidate genes in response to biotic and abiotic stresses using comparative microarrays.

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    Arjun Sham

    Full Text Available Plants have evolved with intricate mechanisms to cope with multiple environmental stresses. To adapt with biotic and abiotic stresses, plant responses involve changes at the cellular and molecular levels. The current study was designed to investigate the effects of combinations of different environmental stresses on the transcriptome level of Arabidopsis genome using public microarray databases. We investigated the role of cyclopentenones in mediating plant responses to environmental stress through TGA (TGACG motif-binding factor transcription factor, independently from jasmonic acid. Candidate genes were identified by comparing plants inoculated with Botrytis cinerea or treated with heat, salt or osmotic stress with non-inoculated or non-treated tissues. About 2.5% heat-, 19% salinity- and 41% osmotic stress-induced genes were commonly upregulated by B. cinerea-treatment; and 7.6%, 19% and 48% of genes were commonly downregulated by B. cinerea-treatment, respectively. Our results indicate that plant responses to biotic and abiotic stresses are mediated by several common regulatory genes. Comparisons between transcriptome data from Arabidopsis stressed-plants support our hypothesis that some molecular and biological processes involved in biotic and abiotic stress response are conserved. Thirteen of the common regulated genes to abiotic and biotic stresses were studied in detail to determine their role in plant resistance to B. cinerea. Moreover, a T-DNA insertion mutant of the Responsive to Dehydration gene (rd20, encoding for a member of the caleosin (lipid surface protein family, showed an enhanced sensitivity to B. cinerea infection and drought. Overall, the overlapping of plant responses to abiotic and biotic stresses, coupled with the sensitivity of the rd20 mutant, may provide new interesting programs for increased plant resistance to multiple environmental stresses, and ultimately increases its chances to survive. Future research

  4. Cytokinin Cross-talking During Biotic and Abiotic Stress Responses

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    Jose Antonio O'Brien

    2013-11-01

    Full Text Available As sessile organisms, plants have to be able to adapt to a continuously changing environment. Plants that perceive some of these changes as stress signals activate signaling pathways to modulate their development and to enable them to survive. The complex responses to environmental cues are to a large extent mediated by plant hormones that together orchestrate the final plant response. The phytohormone cytokinin is involved in many plant developmental processes. Recently, it has been established that cytokinin plays an important role in stress responses, but does not act alone. Indeed, the hormonal control of plant development and stress adaptation is the outcome of a complex network of multiple synergistic and antagonistic interactions between various hormones. Here, we review the recent findings on the cytokinin function as part of this hormonal network. We focus on the importance of the crosstalk between cytokinin and other hormones, such as abscisic acid, jasmonate, salicylic acid, ethylene, and auxin in the modulation of plant development and stress adaptation. Finally, the impact of the current research in the biotechnological industry will be discussed.

  5. Pivoting from Arabidopsis to wheat to understand how agricultural plants integrate responses to biotic stress

    Science.gov (United States)

    Here we argue for a research initiative on gene-for-gene (g-f-g) interactions between wheat and its parasites. One aim is to begin a conversation between the disparate communities of plant pathology and entomology. Another is to understand how responses to biotic stress are integrated in an import...

  6. Transcriptomic responses to biotic stresses in Malus x domestica: a meta-analysis study

    OpenAIRE

    Balan, Bipin; Marra, Francesco Paolo; Caruso, Tiziano; Martinelli, Federico

    2018-01-01

    RNA-Seq analysis is a strong tool to gain insight into the molecular responses to biotic stresses in plants. The objective of this work is to identify specific and common molecular responses between different transcriptomic data related to fungi, virus and bacteria attacks in Malus x domestica. We analyzed seven transcriptomic datasets in Malus x domestica divided in responses to fungal pathogens, virus (Apple Stem Grooving Virus) and bacteria (Erwinia amylovora). Data were dissected using an...

  7. Transcriptomic responses to biotic stresses in Malus x domestica: a meta-analysis study.

    Science.gov (United States)

    Balan, Bipin; Marra, Francesco Paolo; Caruso, Tiziano; Martinelli, Federico

    2018-01-31

    RNA-Seq analysis is a strong tool to gain insight into the molecular responses to biotic stresses in plants. The objective of this work is to identify specific and common molecular responses between different transcriptomic data related to fungi, virus and bacteria attacks in Malus x domestica. We analyzed seven transcriptomic datasets in Malus x domestica divided in responses to fungal pathogens, virus (Apple Stem Grooving Virus) and bacteria (Erwinia amylovora). Data were dissected using an integrated approach of pathway- and gene- set enrichment analysis, Mapman visualization tool, gene ontology analysis and inferred protein-protein interaction network. Our meta-analysis revealed that the bacterial infection enhanced specifically genes involved in sugar alcohol metabolism. Brassinosteroids were upregulated by fungal pathogens while ethylene was highly affected by Erwinia amylovora. Gibberellins and jasmonates were strongly repressed by fungal and viral infections. The protein-protein interaction network highlighted the role of WRKYs in responses to the studied pathogens. In summary, our meta-analysis provides a better understanding of the Malus X domestica transcriptome responses to different biotic stress conditions; we anticipate that these insights will assist in the development of genetic resistance and acute therapeutic strategies. This work would be an example for next meta-analysis works aiming at identifying specific common molecular features linked with biotic stress responses in other specialty crops.

  8. Auxin Response Factors (ARFs are potential mediators of auxin action in tomato response to biotic and abiotic stress (Solanum lycopersicum.

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    Sarah Bouzroud

    Full Text Available Survival biomass production and crop yield are heavily constrained by a wide range of environmental stresses. Several phytohormones among which abscisic acid (ABA, ethylene and salicylic acid (SA are known to mediate plant responses to these stresses. By contrast, the role of the plant hormone auxin in stress responses remains so far poorly studied. Auxin controls many aspects of plant growth and development, and Auxin Response Factors play a key role in the transcriptional activation or repression of auxin-responsive genes through direct binding to their promoters. As a mean to gain more insight on auxin involvement in a set of biotic and abiotic stress responses in tomato, the present study uncovers the expression pattern of SlARF genes in tomato plants subjected to biotic and abiotic stresses. In silico mining of the RNAseq data available through the public TomExpress web platform, identified several SlARFs as responsive to various pathogen infections induced by bacteria and viruses. Accordingly, sequence analysis revealed that 5' regulatory regions of these SlARFs are enriched in biotic and abiotic stress-responsive cis-elements. Moreover, quantitative qPCR expression analysis revealed that many SlARFs were differentially expressed in tomato leaves and roots under salt, drought and flooding stress conditions. Further pointing to the putative role of SlARFs in stress responses, quantitative qPCR expression studies identified some miRNA precursors as potentially involved in the regulation of their SlARF target genes in roots exposed to salt and drought stresses. These data suggest an active regulation of SlARFs at the post-transcriptional level under stress conditions. Based on the substantial change in the transcript accumulation of several SlARF genes, the data presented in this work strongly support the involvement of auxin in stress responses thus enabling to identify a set of candidate SlARFs as potential mediators of biotic and abiotic

  9. Molecular Analysis of Rice CIPKs Involved in Both Biotic and Abiotic Stress Responses

    Institute of Scientific and Technical Information of China (English)

    CHEN Xi-feng; Gu Zhi-min; LIU Feng; MA Bo-jun; ZHANG Hong-sheng

    2011-01-01

    Plant calcineurin B-like (CBL) proteins have been proposed as important Ca2+ sensors and specifically interact with CBL-interacting protein kinases (CIPKs) in plant-specific calcium signaling.Here,we identified and isolated 15 CIPK genes in a japonica rice variety Nipponbare based on the predicted sequences of rice CIPK gene family.Gene structure analysis showed that these 15 genes were divided into intron-less and intron-rich groups,and OsCIPK3 and OsCIPK24 exhibited alternative splicing in their mature process.The phylogenetic analyses indicated that rice CIPKs shared an ancestor with Arabidopsis and poplar CIPKs.Analyses of gene expression showed that these OsCIPK genes were differentially induced by biotic stresses such as bacterial blight and abiotic stresses (heavy metal such as Hg2+,high salinity,cold and ABA).Interestingly,five OsCIPK genes,OsCIPK1,2,10,11 and 12,were transcriptionally up-regulated after bacterial blight infection whereas four OsCIPK genes,OsCIPK2,10,11 and 14,were induced by all treatments,indicating that some of OsCIPK genes are involved in multiple stress response pathways in plants.Our finding suggests that CIPKs play a key role in both biotic and abiotic stress responses.

  10. Adaptation of the MapMan ontology to biotic stress responses: application in solanaceous species

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    Stitt Mark

    2007-09-01

    Full Text Available Abstract Background The results of transcriptome microarray analysis are usually presented as a list of differentially expressed genes. As these lists can be long, it is hard to interpret the desired experimental treatment effect on the physiology of analysed tissue, e.g. via selected metabolic or other pathways. For some organisms, gene ontologies and data visualization software have been implemented to overcome this problem, whereas for others, software adaptation is yet to be done. Results We present the classification of tentative potato contigs from the potato gene index (StGI available from Dana-Farber Cancer Institute (DFCI into the MapMan ontology to enable the application of the MapMan family of tools to potato microarrays. Special attention has been focused on mapping genes that could not be annotated based on similarity to Arabidopsis genes alone, thus possibly representing genes unique for potato. 97 such genes were classified into functional BINs (i.e. functional classes after manual annotation. A new pathway, focusing on biotic stress responses, has been added and can be used for all other organisms for which mappings have been done. The BIN representation on the potato 10 k cDNA microarray, in comparison with all putative potato gene sequences, has been tested. The functionality of the prepared potato mapping was validated with experimental data on plant response to viral infection. In total 43,408 unigenes were mapped into 35 corresponding BINs. Conclusion The potato mappings can be used to visualize up-to-date, publicly available, expressed sequence tags (ESTs and other sequences from GenBank, in combination with metabolic pathways. Further expert work on potato annotations will be needed with the ongoing EST and genome sequencing of potato. The current MapMan application for potato is directly applicable for analysis of data obtained on potato 10 k cDNA microarray by TIGR (The Institute for Genomic Research but can also be used

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

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    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.

  12. Identification and expression of the WRKY transcription factors of Carica papaya in response to abiotic and biotic stresses.

    Science.gov (United States)

    Pan, Lin-Jie; Jiang, Ling

    2014-03-01

    The WRKY transcription factor (TF) plays a very important role in the response of plants to various abiotic and biotic stresses. A local papaya database was built according to the GenBank expressed sequence tag database using the BioEdit software. Fifty-two coding sequences of Carica papaya WRKY TFs were predicted using the tBLASTn tool. The phylogenetic tree of the WRKY proteins was classified. The expression profiles of 13 selected C. papaya WRKY TF genes under stress induction were constructed by quantitative real-time polymerase chain reaction. The expression levels of these WRKY genes in response to 3 abiotic and 2 biotic stresses were evaluated. TF807.3 and TF72.14 are upregulated by low temperature; TF807.3, TF43.76, TF12.199 and TF12.62 are involved in the response to drought stress; TF9.35, TF18.51, TF72.14 and TF12.199 is involved in response to wound; TF12.199, TF807.3, TF21.156 and TF18.51 was induced by PRSV pathogen; TF72.14 and TF43.76 are upregulated by SA. The regulated expression levels of above eight genes normalized against housekeeping gene actin were significant at probability of 0.01 levels. These WRKY TFs could be related to corresponding stress resistance and selected as the candidate genes, especially, the two genes TF807.3 and TF12.199, which were regulated notably by four stresses respectively. This study may provide useful information and candidate genes for the development of transgenic stress tolerant papaya varieties.

  13. TaWRKY68 responses to biotic stresses are revealed by the orthologous genes from major cereals

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    Bo Ding

    2014-01-01

    Full Text Available WRKY transcription factors have been extensively characterized in the past 20 years, but in wheat, studies onWRKY genes and their function are lagging behind many other species. To explore the function of wheat WRKY genes, we identified a TaWRKY68 gene from a common wheat cultivar. It encodes a protein comprising 313 amino acids which harbors 19 conserved motifs or active sites. Gene expression patterns were determined by analyzing microarray data of TaWRKY68 in wheat and of orthologous genes from maize, rice and barley using Genevestigator. TaWRKY68 orthologs were identified and clustered using DELTA-BLAST and COBALT programs available at NCBI. The results showed that these genes, which are expressed in all tissues tested, had relatively higher levels in the roots and were up-regulated in response to biotic stresses. Bioinformatics results were confirmed by RT-PCR experiments using wheat plants infected by Agrobacterium tumefaciens and Blumeria graminis, or treated with Deoxynivalenol, a Fusarium graminearum-induced mycotoxin in wheat or barley. In summary,TaWRKY68 functions differ during plant developmental stages and might be representing a hub gene function in wheat responses to various biotic stresses. It was also found that including data from major cereal genes in the bioinformatics analysis gave more accurate and comprehensive predictions of wheat gene functions.

  14. Role of miRNAs and siRNAs in biotic and abiotic stress responses of plants

    KAUST Repository

    Khraiwesh, Basel

    2012-02-01

    Small, non-coding RNAs are a distinct class of regulatory RNAs in plants and animals that control a variety of biological processes. In plants, several classes of small RNAs with specific sizes and dedicated functions have evolved through a series of pathways. The major classes of small RNAs include microRNAs (miRNAs) and small interfering RNAs (siRNAs), which differ in their biogenesis. miRNAs control the expression of cognate target genes by binding to reverse complementary sequences, resulting in cleavage or translational inhibition of the target RNAs. siRNAs have a similar structure, function, and biogenesis as miRNAs but are derived from long double-stranded RNAs and can often direct DNA methylation at target sequences. Besides their roles in growth and development and maintenance of genome integrity, small RNAs are also important components in plant stress responses. One way in which plants respond to environmental stress is by modifying their gene expression through the activity of small RNAs. Thus, understanding how small RNAs regulate gene expression will enable researchers to explore the role of small RNAs in biotic and abiotic stress responses. This review focuses on the regulatory roles of plant small RNAs in the adaptive response to stresses. This article is part of a Special Issue entitled: Plant gene regulation in response to abiotic stress. © 2011 Elsevier B.V.

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

    Science.gov (United States)

    Creelman, R A; Mullet, J E

    1995-05-09

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

  16. Genome-Wide Identification, Characterization, and Expression Analysis of Small RNA Biogenesis Purveyors Reveal Their Role in Regulation of Biotic Stress Responses in Three Legume Crops

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    Rajeev K. Varshney

    2017-04-01

    Full Text Available Biotic stress in legume crops is one of the major threats to crop yield and productivity. Being sessile organisms, plants have evolved a myriad of mechanisms to combat different stresses imposed on them. One such mechanism, deciphered in the last decade, is small RNA (sRNA mediated defense in plants. Small RNAs (sRNAs have emerged as one of the major players in gene expression regulation in plants during developmental stages and under stress conditions. They are known to act both at transcriptional and post-transcriptional levels. Dicer-like (DCL, Argonaute (AGO, and RNA dependent RNA polymerase (RDR constitute the major components of sRNA biogenesis machinery and are known to play a significant role in combating biotic and abiotic stresses. This study is, therefore, focused on identification and characterization of sRNA biogenesis proteins in three important legume crops, namely chickpea, pigeonpea, and groundnut. Phylogenetic analysis of these proteins between legume species classified them into distinct clades and suggests the evolutionary conservation of these genes across the members of Papillionidoids subfamily. Variable expression of sRNA biogenesis genes in response to the biotic stresses among the three legumes indicate the possible existence of specialized regulatory mechanisms in different legumes. This is the first ever study to understand the role of sRNA biogenesis genes in response to pathogen attacks in the studied legumes.

  17. Genome-wide identification and expression profiling of tomato Hsp20 gene family in response to biotic and abiotic stresses

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    jiahong yu

    2016-08-01

    levels of SlHsp20 genes could be induced profusely by abiotic and biotic stresses such as heat, drought, salt, Botrytis cinerea and Tomato Spotted Wilt Virus, indicating their potential roles in mediating the response of tomato plants to environment stresses. In conclusion, these results provide valuable information for elucidating the evolutionary relationship of Hsp20 gene family and functional characterization of the SlHsp20 gene family in the future.

  18. Genome-Wide Identification and Expression Profiling of Tomato Hsp20 Gene Family in Response to Biotic and Abiotic Stresses.

    Science.gov (United States)

    Yu, Jiahong; Cheng, Yuan; Feng, Kun; Ruan, Meiying; Ye, Qingjing; Wang, Rongqing; Li, Zhimiao; Zhou, Guozhi; Yao, Zhuping; Yang, Yuejian; Wan, Hongjian

    2016-01-01

    genes could be induced profusely by abiotic and biotic stresses such as heat, drought, salt, Botrytis cinerea, and Tomato Spotted Wilt Virus (TSWV), indicating their potential roles in mediating the response of tomato plants to environment stresses. In conclusion, these results provide valuable information for elucidating the evolutionary relationship of Hsp20 gene family and functional characterization of the SlHsp20 gene family in the future.

  19. Role of miRNAs and siRNAs in biotic and abiotic stress responses of plants

    KAUST Repository

    Khraiwesh, Basel; Zhu, Jian-Kang; Zhu, Jianhua

    2012-01-01

    in growth and development and maintenance of genome integrity, small RNAs are also important components in plant stress responses. One way in which plants respond to environmental stress is by modifying their gene expression through the activity of small

  20. Changes in the Arabidopsis thaliana Proteome Implicate cAMP in Biotic and Abiotic Stress Responses and Changes in Energy Metabolism

    KAUST Repository

    Alquraishi, May Majed; Gehring, Christoph A; Marondedze, Claudius

    2016-01-01

    The second messenger 3′,5′-cyclic adenosine monophosphate (cAMP) is increasingly recognized as having many different roles in plant responses to environmental stimuli. To gain further insights into these roles, Arabidopsis thaliana cell suspension culture was treated with 100 nM of cell permeant 8-bromo-cAMP for 5 or 10 min. Here, applying mass spectrometry and comparative proteomics, 20 proteins were identified as differentially expressed and we noted a specific bias in proteins with a role in abiotic stress, particularly cold and salinity, biotic stress as well as proteins with a role in glycolysis. These findings suggest that cAMP is sufficient to elicit specific stress responses that may in turn induce complex changes to cellular energy homeostasis.

  1. Changes in the Arabidopsis thaliana Proteome Implicate cAMP in Biotic and Abiotic Stress Responses and Changes in Energy Metabolism

    KAUST Repository

    Alquraishi, May Majed

    2016-06-01

    The second messenger 3′,5′-cyclic adenosine monophosphate (cAMP) is increasingly recognized as having many different roles in plant responses to environmental stimuli. To gain further insights into these roles, Arabidopsis thaliana cell suspension culture was treated with 100 nM of cell permeant 8-bromo-cAMP for 5 or 10 min. Here, applying mass spectrometry and comparative proteomics, 20 proteins were identified as differentially expressed and we noted a specific bias in proteins with a role in abiotic stress, particularly cold and salinity, biotic stress as well as proteins with a role in glycolysis. These findings suggest that cAMP is sufficient to elicit specific stress responses that may in turn induce complex changes to cellular energy homeostasis.

  2. Gene response in rice plants treated with continuous fog influenced by pH, was similar to that treated with biotic stress.

    Science.gov (United States)

    Satoh, Kouji; Saji, Shoko; Ito, Shoko; Shimizu, Hideyuki; Saji, Hikaru; Kikuchi, Shoshi

    2014-01-01

    Throughout Asia, including Japan, rice plants are cultivated in a wide range of areas from lowlands to highlands and are frequently exposed to fog, including acid fog. Some physiological studies have shown that acid fog can be a stress factor for plants. We analyzed the gene expression profiles of rice plants treated with artificially prepared simulated acid fog (SiAF) or simulated neutral fog (SiNF) for 1 or 7 days. Microarray analysis results suggested that both the SiAF and the SiNF treatments induced the expression of genes involved in the defense and stress responses in rice plants. Induction of such genes was detected in plants treated with SiAF for 1 day, and the number of induced genes increased in plants treated with SiAF for 7 days. The genes for defense and stress responses were also induced by SiNF for 7 days, although they were not induced by SiNF for 1 day. The gene expression profiles of the SiAF-treated and the SiNF-treated plants were compared to those of plants treated with other stress factors. The comparison revealed that both SiAF and SiNF treatments have similar effects to biotic stresses and ozone stress. The genes encoding NADPH oxidase and germin, which function in apoplasts, were also induced by SiAF, SiNF and biotic stresses. These findings suggest that both the SiAF and the SiNF treatments may result in oxidative stress through the apoplastic production of reactive oxygen species.

  3. Plant response to biotic stress: Is there a common epigenetic response during plant-pathogenic and symbiotic interactions?

    Science.gov (United States)

    Zogli, Prince; Libault, Marc

    2017-10-01

    Plants constantly interact with pathogenic and symbiotic microorganisms. Recent studies have revealed several regulatory mechanisms controlling these interactions. Among them, the plant defense system is activated not only in response to pathogenic, but also in response to symbiotic microbes. Interestingly, shortly after symbiotic microbial recognition, the plant defense system is suppressed to promote plant infection by symbionts. Research studies have demonstrated the influence of the plant epigenome in modulating both pathogenic and symbiotic plant-microbe interactions, thereby influencing plant survival, adaptation and evolution of the plant response to microbial infections. It is however unclear if plant pathogenic and symbiotic responses share similar epigenomic profiles or if epigenomic changes differentially regulate plant-microbe symbiosis and pathogenesis. In this mini-review, we provide an update of the current knowledge of epigenomic control on plant immune responses and symbiosis, with a special attention being paid to knowledge gap and potential strategies to fill-in the missing links. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Differential expression of calcium/calmodulin-regulated SlSRs in response to abiotic and biotic stresses in tomato fruit.

    Science.gov (United States)

    Yang, Tianbao; Peng, Hui; Whitaker, Bruce D; Jurick, Wayne M

    2013-07-01

    Calcium has been shown to enhance stress tolerance, maintain firmness and reduce decay in fruits. Previously we reported that seven tomato SlSRs encode calcium/calmodulin-regulated proteins, and that their expressions are developmentally regulated during fruit development and ripening, and are also responsive to ethylene. To study their expressions in response to stresses encountered during postharvest handling, tomato fruit at the mature-green stage was subjected to chilling and wounding injuries, infected with Botrytis cinerea and treated with salicylic acid or methyl jasmonate. Gene expression studies revealed that the seven SlSRs differentially respond to different stress signals. SlSR2 was the only gene upregulated by all the treatments. SlSR4 acted as a late pathogen-induced gene; it was upregulated by salicylic acid and methyl jasmonate, but downregulated by cold treatment. SlSR3L was cold- and wound-responsive and was also induced by salicylic acid. SlSR1 and SlSR1L were repressed by cold, wounding and pathogen infection, but were upregulated by salicylic acid and methyl jasmonate. Overall, results of these expression studies indicate that individual SlSRs have distinct roles in responses to the specific stress signals, and SlSRs may act as a coordinator(s) connecting calcium-mediated signaling with other stress signal transduction pathways during fruit ripening and storage. © 2013 Scandinavian Plant Physiology Society.

  5. Genome-wide identification of WRKY transcription factors in kiwifruit (Actinidia spp.) and analysis of WRKY expression in responses to biotic and abiotic stresses.

    Science.gov (United States)

    Jing, Zhaobin; Liu, Zhande

    2018-04-01

    As one of the largest transcriptional factor families in plants, WRKY transcription factors play important roles in various biotic and abiotic stress responses. To date, WRKY genes in kiwifruit (Actinidia spp.) remain poorly understood. In our study, o total of 97 AcWRKY genes have been identified in the kiwifruit genome. An overview of these AcWRKY genes is analyzed, including the phylogenetic relationships, exon-intron structures, synteny and expression profiles. The 97 AcWRKY genes were divided into three groups based on the conserved WRKY domain. Synteny analysis indicated that segmental duplication events contributed to the expansion of the kiwifruit AcWRKY family. In addition, the synteny analysis between kiwifruit and Arabidopsis suggested that some of the AcWRKY genes were derived from common ancestors before the divergence of these two species. Conserved motifs outside the AcWRKY domain may reflect their functional conservation. Genome-wide segmental and tandem duplication were found, which may contribute to the expansion of AcWRKY genes. Furthermore, the analysis of selected AcWRKY genes showed a variety of expression patterns in five different organs as well as during biotic and abiotic stresses. The genome-wide identification and characterization of kiwifruit WRKY transcription factors provides insight into the evolutionary history and is a useful resource for further functional analyses of kiwifruit.

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

    DEFF Research Database (Denmark)

    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...

  7. Functional and DNA-protein binding studies of WRKY transcription factors and their expression analysis in response to biotic and abiotic stress in wheat (Triticum aestivum L.).

    Science.gov (United States)

    Satapathy, Lopamudra; Kumar, Dhananjay; Kumar, Manish; Mukhopadhyay, Kunal

    2018-01-01

    WRKY, a plant-specific transcription factor family, plays vital roles in pathogen defense, abiotic stress, and phytohormone signalling. Little is known about the roles and function of WRKY transcription factors in response to rust diseases in wheat. In the present study, three TaWRKY genes encoding complete protein sequences were cloned. They belonged to class II and III WRKY based on the number of WRKY domains and the pattern of zinc finger structures. Twenty-two DNA-protein binding docking complexes predicted stable interactions of WRKY domain with W-box. Quantitative real-time-PCR using wheat near-isogenic lines with or without Lr28 gene revealed differential up- or down-regulation in response to biotic and abiotic stress treatments which could be responsible for their functional divergence in wheat. TaWRKY62 was found to be induced upon treatment with JA, MJ, and SA and reduced after ABA treatments. Maximum induction of six out of seven genes occurred at 48 h post inoculation due to pathogen inoculation. Hence, TaWRKY (49, 50 , 52 , 55 , 57, and 62 ) can be considered as potential candidate genes for further functional validation as well as for crop improvement programs for stress resistance. The results of the present study will enhance knowledge towards understanding the molecular basis of mode of action of WRKY transcription factor genes in wheat and their role during leaf rust pathogenesis in particular.

  8. Quantitative patterns between plant volatile emissions induced by biotic stresses and the degree of damage

    Directory of Open Access Journals (Sweden)

    Ülo eNiinemets

    2013-07-01

    Full Text Available Plants have to cope with a plethora of biotic stresses such as herbivory and pathogen attacks throughout their life cycle. The biotic stresses typically trigger rapid emissions of volatile products of lipoxygenase pathway (LOX products, various C6 aldehydes, alcohols and derivatives, also called green leaf volatiles associated with oxidative burst. Further a variety of defense pathways is activated, leading to induction of synthesis and emission of a complex blend of volatiles, often including methyl salicylate, indole, mono-, homo- and sesquiterpenes. The airborne volatiles are involved in systemic responses leading to elicitation of emissions from non-damaged plant parts. For several abiotic stresses, it has been demonstrated that volatile emissions are quantitatively related to the stress dose. The biotic impacts under natural conditions vary in severity from mild to severe, but it is unclear whether volatile emissions also scale with the severity of biotic stresses in a dose-dependent manner. Furthermore, biotic impacts are typically recurrent, but it is poorly understood how direct stress-triggered and systemic emission responses are silenced during periods intervening sequential stress events. Here we review the information on induced emissions elicited in response to biotic attacks, and argue that biotic stress severity vs. emission rate relationships should follow principally the same dose-response relationships as previously demonstrated for several abiotic stresses. Analysis of several case studies investigating the elicitation of emissions in response to chewing herbivores, aphids, rust fungi, powdery mildew and Botrytis, suggests that induced emissions do respond to stress severity in dose-dependent manner. Bi-phasic emission kinetics of several induced volatiles have been demonstrated in these experiments, suggesting that next to immediate stress-triggered emissions, biotic stress elicited emissions typically have a secondary

  9. Transcriptomic analysis of grain amaranth (Amaranthus hypochondriacus using 454 pyrosequencing: comparison with A. tuberculatus, expression profiling in stems and in response to biotic and abiotic stress

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    Vargas-Ortiz Erandi

    2011-07-01

    Full Text Available Abstract Background Amaranthus hypochondriacus, a grain amaranth, is a C4 plant noted by its ability to tolerate stressful conditions and produce highly nutritious seeds. These possess an optimal amino acid balance and constitute a rich source of health-promoting peptides. Although several recent studies, mostly involving subtractive hybridization strategies, have contributed to increase the relatively low number of grain amaranth expressed sequence tags (ESTs, transcriptomic information of this species remains limited, particularly regarding tissue-specific and biotic stress-related genes. Thus, a large scale transcriptome analysis was performed to generate stem- and (abiotic stress-responsive gene expression profiles in grain amaranth. Results A total of 2,700,168 raw reads were obtained from six 454 pyrosequencing runs, which were assembled into 21,207 high quality sequences (20,408 isotigs + 799 contigs. The average sequence length was 1,064 bp and 930 bp for isotigs and contigs, respectively. Only 5,113 singletons were recovered after quality control. Contigs/isotigs were further incorporated into 15,667 isogroups. All unique sequences were queried against the nr, TAIR, UniRef100, UniRef50 and Amaranthaceae EST databases for annotation. Functional GO annotation was performed with all contigs/isotigs that produced significant hits with the TAIR database. Only 8,260 sequences were found to be homologous when the transcriptomes of A. tuberculatus and A. hypochondriacus were compared, most of which were associated with basic house-keeping processes. Digital expression analysis identified 1,971 differentially expressed genes in response to at least one of four stress treatments tested. These included several multiple-stress-inducible genes that could represent potential candidates for use in the engineering of stress-resistant plants. The transcriptomic data generated from pigmented stems shared similarity with findings reported in developing

  10. Investigating the roles of MicroRNAs in biotic stress response induced by Rhizoctonia solani in rice

    Energy Technology Data Exchange (ETDEWEB)

    Syuhada, O. Nurfarahana; Kalaivani, N. [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2014-09-03

    Sheath blight disease, caused by Rhizoctonia solani 1802/KB was screened on two rice varieties, Oryza sativaindica cultivar MR219 and Oryza sativa indica cultivar UKMRC9. The disease symptom was severe in MR219 compared to UKMRC9. Total RNA from R. solani 1802/KB, infected rice leaves of MR219 and infected rice leaves of UKMRC9 were extracted using TRIzol reagent, purified and sent for small RNA sequencing. Three miRNA libraries were generated and analyzed. The libraries generated 65 805, 78 512 and 81 325 known miRNAs respectively. The structure of miRNA of these samples was predicted. The up-regulated and down-regulated of miRNAs target gene prediction and its target functions were discovered and were mainly related to the growth and development of metabolism, protein transport, transcriptional regulation, stress response, and hormone signaling and electron transfer. Sheath blight-induced differential expression of known miRNAs tends to targetMYB transcription factor, F-box proteins, NBS-LRR, leucine-rich repeat receptor protein kinases and zinc finger proteins. Detecting new miRNAs and measuring the expression profiles of known miRNAs is an important tasks required for a better understanding of various biological conditions. Therefore, further analysis using Gene Ontology Slim will be conducted to deduce some biological information from the datasets obtained.

  11. Regulation of Translation Initiation under Biotic and Abiotic Stresses

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    Ana B. Castro-Sanz

    2013-02-01

    Full Text Available Plants have developed versatile strategies to deal with the great variety of challenging conditions they are exposed to. Among them, the regulation of translation is a common target to finely modulate gene expression both under biotic and abiotic stress situations. Upon environmental challenges, translation is regulated to reduce the consumption of energy and to selectively synthesize proteins involved in the proper establishment of the tolerance response. In the case of viral infections, the situation is more complex, as viruses have evolved unconventional mechanisms to regulate translation in order to ensure the production of the viral encoded proteins using the plant machinery. Although the final purpose is different, in some cases, both plants and viruses share common mechanisms to modulate translation. In others, the mechanisms leading to the control of translation are viral- or stress-specific. In this paper, we review the different mechanisms involved in the regulation of translation initiation under virus infection and under environmental stress in plants. In addition, we describe the main features within the viral RNAs and the cellular mRNAs that promote their selective translation in plants undergoing biotic and abiotic stress situations.

  12. Effect of abiotic and biotic stress factors analysis using machine learning methods in zebrafish.

    Science.gov (United States)

    Gutha, Rajasekar; Yarrappagaari, Suresh; Thopireddy, Lavanya; Reddy, Kesireddy Sathyavelu; Saddala, Rajeswara Reddy

    2018-03-01

    In order to understand the mechanisms underlying stress responses, meta-analysis of transcriptome is made to identify differentially expressed genes (DEGs) and their biological, molecular and cellular mechanisms in response to stressors. The present study is aimed at identifying the effect of abiotic and biotic stress factors, and it is found that several stress responsive genes are common for both abiotic and biotic stress factors in zebrafish. The meta-analysis of micro-array studies revealed that almost 4.7% i.e., 108 common DEGs are differentially regulated between abiotic and biotic stresses. This shows that there is a global coordination and fine-tuning of gene regulation in response to these two types of challenges. We also performed dimension reduction methods, principal component analysis, and partial least squares discriminant analysis which are able to segregate abiotic and biotic stresses into separate entities. The supervised machine learning model, recursive-support vector machine, could classify abiotic and biotic stresses with 100% accuracy using a subset of DEGs. Beside these methods, the random forests decision tree model classified five out of 8 stress conditions with high accuracy. Finally, Functional enrichment analysis revealed the different gene ontology terms, transcription factors and miRNAs factors in the regulation of stress responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The Role of Silicon under Biotic and Abiotic Stress Conditions

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    İlkay YAVAŞ

    2017-06-01

    Full Text Available Biotic and abiotic stress factors can adversely affect the agricultural productivity leading to physiological and biochemical damage to crops. Therefore, the most effective way is to increase the resistance to stresses. Silicon plays a ro le in reducing the effects of abiotic and biotic stresses (drought, salt stress, disease and insect stress etc. on plants. Silicon is accumulated in the cell walls and intercellular spaces and thus it has beneficial effects on disease infestations in especially small grains. The application of silicon may reduce the effects of environmental stresses on plants while making effective use of plant nutrients such as nitrogen and phosphorous. Also, silicon may reduce the toxic effects of heavy metals in soil. I t may protect the foliage and increase light uptake and reduce respiration. Therefore, in this review, we discussed the effects of silicon on abiotic and biotic stresses in especially field crops.

  14. STRESS ECOLOGY IN FUCUS : ABIOTIC, BIOTIC AND GENETIC INTERACTIONS

    NARCIS (Netherlands)

    Wahl, Martin; Jormalainen, Veijo; Eriksson, Britas Klemens; Coyer, James A.; Molis, Markus; Schubert, Hendrik; Dethier, Megan; Karez, Rolf; Kruse, Inken; Lenz, Mark; Pearson, Gareth; Rohde, Sven; Wikstrom, Sofia A.; Olsen, Jeanine L.; Lesser, M

    2011-01-01

    Stress regimes defined as the synchronous or sequential action of abiotic and biotic stresses determine the performance and distribution of species. The natural patterns of stress to which species are more or less well adapted have recently started to shift and alter under the influence of global

  15. Transcriptome Analysis of Sunflower Genotypes with Contrasting Oxidative Stress Tolerance Reveals Individual- and Combined- Biotic and Abiotic Stress Tolerance Mechanisms.

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    Vemanna S Ramu

    Full Text Available In nature plants are often simultaneously challenged by different biotic and abiotic stresses. Although the mechanisms underlying plant responses against single stress have been studied considerably, plant tolerance mechanisms under combined stress is not understood. Also, the mechanism used to combat independently and sequentially occurring many number of biotic and abiotic stresses has also not systematically studied. From this context, in this study, we attempted to explore the shared response of sunflower plants to many independent stresses by using meta-analysis of publically available transcriptome data and transcript profiling by quantitative PCR. Further, we have also analyzed the possible role of the genes so identified in contributing to combined stress tolerance. Meta-analysis of transcriptomic data from many abiotic and biotic stresses indicated the common representation of oxidative stress responsive genes. Further, menadione-mediated oxidative stress in sunflower seedlings showed similar pattern of changes in the oxidative stress related genes. Based on this a large scale screening of 55 sunflower genotypes was performed under menadione stress and those contrasting in oxidative stress tolerance were identified. Further to confirm the role of genes identified in individual and combined stress tolerance the contrasting genotypes were individually and simultaneously challenged with few abiotic and biotic stresses. The tolerant hybrid showed reduced levels of stress damage both under combined stress and few independent stresses. Transcript profiling of the genes identified from meta-analysis in the tolerant hybrid also indicated that the selected genes were up-regulated under individual and combined stresses. Our results indicate that menadione-based screening can identify genotypes not only tolerant to multiple number of individual biotic and abiotic stresses, but also the combined stresses.

  16. Compartment specific importance of glutathione during abiotic and biotic stress

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    Bernd eZechmann

    2014-10-01

    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  17. Utilizing Genetic Resources and Precision Agriculture to Enhance Resistance to Biotic and Abiotic Stress in Watermelon

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    Mihail KANTOR

    2018-03-01

    Full Text Available Originally from Africa, watermelon is a staple crop in South Carolina and rich source of important phytochemicals that promote human health. As a result of many years of domestication and selection for desired fruit quality, modern watermelon cultivars are susceptible to biotic and abiotic stress. The present review discusses how genetic selection and breeding combined with geospatial technologies (precision agriculture may help enhance watermelon varieties for resistance to biotic and abiotic stress. Gene loci identified and selected in undomesticated watermelon accessions are responsible for resistance to diseases, pests and abiotic stress. Vegetable breeding programs use traditional breeding methodologies and genomic tools to introduce gene loci conferring biotic or abiotic resistance into the genome background of elite watermelon cultivars. This continuous approach of collecting, evaluating and identifying useful genetic material is valuable for enhancing genetic diversity and tolerance and combined with precision agriculture could increase food security in the Southeast.

  18. Diagnosis of abiotic and biotic stress factors using the visible symptoms in foliage

    International Nuclear Information System (INIS)

    Vollenweider, P.; Guenthardt-Goerg, Madeleine S.

    2005-01-01

    Visible symptoms in the foliage of trees are recorded to monitor the effects of abiotic and biotic stress. Difficulties are reported in diagnosing the origin of stress. The present paper discusses several diagnostic criteria which are usable in different species for a better determination of the stress factor type. A new diagnosis scheme to differentiate between classes of abiotic and biotic stress factors is supplied. Abiotic stress generates gradients of symptoms. The symptom specificity is determined by the degree of interaction between the stress factor and plant defense system. Symptoms caused by abiotic stress and natural autumnal senescence can be morphologically different or undistinguishable according to the stress and plant species. With biotic stress, the class of parasitic is generally recognizable on the basis of the visible symptoms. Structurally and physiologically based explanations of the symptom morphology are still missing for many stress factors. - The morphology and distribution of visible stress symptoms in tree foliage provides diagnostic tools to identify plant defense responses and differentiate stress from natural senescence symptoms

  19. Evolution and Adaptation of Wild Emmer Wheat Populations to Biotic and Abiotic Stresses.

    Science.gov (United States)

    Huang, Lin; Raats, Dina; Sela, Hanan; Klymiuk, Valentina; Lidzbarsky, Gabriel; Feng, Lihua; Krugman, Tamar; Fahima, Tzion

    2016-08-04

    The genetic bottlenecks associated with plant domestication and subsequent selection in man-made agroecosystems have limited the genetic diversity of modern crops and increased their vulnerability to environmental stresses. Wild emmer wheat, the tetraploid progenitor of domesticated wheat, distributed along a wide range of ecogeographical conditions in the Fertile Crescent, has valuable "left behind" adaptive diversity to multiple diseases and environmental stresses. The biotic and abiotic stress responses are conferred by series of genes and quantitative trait loci (QTLs) that control complex resistance pathways. The study of genetic diversity, genomic organization, expression profiles, protein structure and function of biotic and abiotic stress-resistance genes, and QTLs could shed light on the evolutionary history and adaptation mechanisms of wild emmer populations for their natural habitats. The continuous evolution and adaptation of wild emmer to the changing environment provide novel solutions that can contribute to safeguarding food for the rapidly growing human population.

  20. Environmental Maternal Effects Mediate the Resistance of Maritime Pine to Biotic Stress

    Science.gov (United States)

    Vivas, María; Zas, Rafael; Sampedro, Luis; Solla, Alejandro

    2013-01-01

    The resistance to abiotic stress is increasingly recognised as being impacted by maternal effects, given that environmental conditions experienced by parent (mother) trees affect stress tolerance in offspring. We hypothesised that abiotic environmental maternal effects may also mediate the resistance of trees to biotic stress. The influence of maternal environment and maternal genotype and the interaction of these two factors on early resistance of Pinus pinaster half-sibs to the Fusarium circinatum pathogen was studied using 10 mother genotypes clonally replicated in two contrasting environments. Necrosis length of infected seedlings was 16% shorter in seedlings grown from favourable maternal environment seeds than in seedlings grown from unfavourable maternal environment seeds. Damage caused by F. circinatum was mediated by maternal environment and maternal genotype, but not by seed mass. Mechanisms unrelated to seed provisioning, perhaps of epigenetic nature, were probably involved in the transgenerational plasticity of P. pinaster, mediating its resistance to biotic stress. Our findings suggest that the transgenerational resistance of pines due to an abiotic stress may interact with the defensive response of pines to a biotic stress. PMID:23922944

  1. Environmental maternal effects mediate the resistance of maritime pine to biotic stress.

    Directory of Open Access Journals (Sweden)

    María Vivas

    Full Text Available The resistance to abiotic stress is increasingly recognised as being impacted by maternal effects, given that environmental conditions experienced by parent (mother trees affect stress tolerance in offspring. We hypothesised that abiotic environmental maternal effects may also mediate the resistance of trees to biotic stress. The influence of maternal environment and maternal genotype and the interaction of these two factors on early resistance of Pinus pinaster half-sibs to the Fusarium circinatum pathogen was studied using 10 mother genotypes clonally replicated in two contrasting environments. Necrosis length of infected seedlings was 16% shorter in seedlings grown from favourable maternal environment seeds than in seedlings grown from unfavourable maternal environment seeds. Damage caused by F. circinatum was mediated by maternal environment and maternal genotype, but not by seed mass. Mechanisms unrelated to seed provisioning, perhaps of epigenetic nature, were probably involved in the transgenerational plasticity of P. pinaster, mediating its resistance to biotic stress. Our findings suggest that the transgenerational resistance of pines due to an abiotic stress may interact with the defensive response of pines to a biotic stress.

  2. Cross-tolerance to biotic and abiotic stresses in plants: a focus on resistance to aphid infestation.

    Science.gov (United States)

    Foyer, Christine H; Rasool, Brwa; Davey, Jack W; Hancock, Robert D

    2016-03-01

    Plants co-evolved with an enormous variety of microbial pathogens and insect herbivores under daily and seasonal variations in abiotic environmental conditions. Hence, plant cells display a high capacity to respond to diverse stresses through a flexible and finely balanced response network that involves components such as reduction-oxidation (redox) signalling pathways, stress hormones and growth regulators, as well as calcium and protein kinase cascades. Biotic and abiotic stress responses use common signals, pathways and triggers leading to cross-tolerance phenomena, whereby exposure to one type of stress can activate plant responses that facilitate tolerance to several different types of stress. While the acclimation mechanisms and adaptive responses that facilitate responses to single biotic and abiotic stresses have been extensively characterized, relatively little information is available on the dynamic aspects of combined biotic/abiotic stress response. In this review, we consider how the abiotic environment influences plant responses to attack by phloem-feeding aphids. Unravelling the signalling cascades that underpin cross-tolerance to biotic and abiotic stresses will allow the identification of new targets for increasing environmental resilience in crops. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. The biochar effect: plant resistance to biotic stresses

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    YIGAL ELAD

    2012-01-01

    Full Text Available Biochar (charcoal is the solid co-product of pyrolysis, the thermal degradation of biomass in the absence of oxygen. Pyrolysis also yields gaseous and liquid biofuel products. There is a growing interest worldwide in the pyrolysis platform, for at least four reasons: (i pyrolysis can be a source of renewable biofuels; (ii many biomass waste materials can be treated by pyrolysis and thus converted into a fuel resource; (iii long-term sequestration of carbon dioxide which originated in the atmosphere may result from adding biochar to soil; and (iv biochar soil amendment contributes to improved soil fertility and crop productivity. Currently, however, very little biochar is utilized in agriculture, in part because its agronomic value in terms of crop response and soil health benefits have yet to be quantified, and because the mechanisms by which it improves soil fertility are poorly understood. The positive effects of biochar on crop productivity under conditions of extensive agriculture are frequently attributed to direct effects of biochar-supplied nutrients and to several other indirect effects, including increased water and nutrient retention, improvements in soil pH, increased soil cation exchange capacity, effects on P and S transformations and turnover, neutralization of phytotoxic compounds in the soil, improved soil physical properties, promotion of mycorrhizal fungi, and alteration of soil microbial populations and functions. Yet, the biochar effect is also evident under conditions of intensive production where many of these parameters are not limited. Biochar addition to soil alters microbial populations in the rhizosphere, albeit via mechanisms not yet understood, and may cause a shift towards beneficial microorganism populations that promote plant growth and resistance to biotic stresses. In addition to some scant evidence for biochar-induced plant protection against soilborne diseases, the induction of systemic resistance towards

  4. HFB7 - A novel orphan hydrophobin of the Harzianum and Virens clades of Trichoderma, is involved in response to biotic and abiotic stresses.

    Science.gov (United States)

    Przylucka, Agnes; Akcapinar, Gunseli Bayram; Chenthamara, Komal; Cai, Feng; Grujic, Marica; Karpenko, Juriy; Livoi, Miriam; Shen, Qirong; Kubicek, Christian P; Druzhinina, Irina S

    2017-05-01

    Hydrophobins are small secreted cysteine-rich proteins exclusively found in fungi. They are able to self-assemble in single molecular layers at hydrophobic-hydrophilic interfaces and can therefore be directly involved in establishment of fungi in their habitat. The genomes of filamentous mycotrophic fungi Trichoderma encode a rich diversity of hydrophobins, which are divided in several groups based on their structure and evolution. Here we describe a new member of class II hydrophobins, HFB7, that has a taxonomically restricted occurrence in Harzianum and Virens clades of Trichoderma. Evolutionary analysis reveals that HFB7 proteins form a separate clade distinct from other Trichoderma class II hydrophobins and that genes encoding them evolve under positive selection pressure. Homology modelling of HFB7 structure in comparison to T. reesei HFB2 reveals that the two large hydrophobic patches on the surface of the protein are remarkably conserved between the two hydrophobins despite significant difference in their primary structures. Expression of hfb7 gene in T. virens increases at interactions with other fungi and a plant and in response to a diversity of abiotic stress conditions, and is also upregulated during formation of aerial mycelium in a standing liquid culture. This upregulation significantly exceeds that of expression of hfb7 under a strong constitutive promoter, and T. virens strains overexpressing hfb7 thus display only changes in traits characterized by low hfb7 expression, i.e. faster growth in submerged liquid culture. The hfb7 gene is not expressed in conidia. Our data allow to conclude that this protein is involved in defence of Trichoderma against a diversity of stress factors related to the oxidative stress. Moreover, HFB7 likely helps in the establishment of the fungus in wetlands or other conditions related to high humidity. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Early biotic stress detection in tomato ( Solanum lycopersicum ) by BVOC emissions

    NARCIS (Netherlands)

    Kasal-Slavik, Tina; Eschweiler, Julia; Kleist, Einhard; Mumm, Roland; Goldbach, Heiner E.; Schouten, Sander; Wildt, Jürgen

    2017-01-01

    We investigated impacts of early and mild biotic stress on Biogenic Volatile Organic Compounds (BVOC) emissions from tomato in order to test their potential for early (biotic) stress detection. Tomato plants were exposed to two common fungal pathogens, Botrytis cinerea and Oidium neolycopesici and

  6. Alcohol dehydrogenase 1 (ADH1) confers both abiotic and biotic stress resistance in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Liu, Wen; Yao, Yue; Wei, Yunxie; Chan, Zhulong

    2017-09-01

    Although the transcriptional regulation and upstream transcription factors of AtADH1 in response to abiotic stress are widely revealed, the in vivo roles of AtADH1 remain unknown. In this study, we found that the expression of AtADH1 was largely induced after salt, drought, cold and pathogen infection. Further studies found that AtADH1 overexpressing plants were more sensitive to abscisic acid (ABA) in comparison to wide type (WT), while AtADH1 knockout mutants showed no significant difference compared with WT in ABA sensitivity. Consistently, AtADH1 overexpressing plants showed improved stress resistance to salt, drought, cold and pathogen infection than WT, but the AtADH1 knockout mutants had no significant difference in abiotic and biotic stress resistance. Moreover, overexpression of AtADH1 expression increased the transcript levels of multiple stress-related genes, accumulation of soluble sugars and callose depositions. All these results indicate that AtADH1 confers enhanced resistance to both abiotic and biotic stresses. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Transcription of Biotic Stress Associated Genes in White Clover (Trifolium repens L.) Differs in Response to Cyst and Root-Knot Nematode Infection.

    Science.gov (United States)

    Islam, Afsana; Mercer, Chris F; Leung, Susanna; Dijkwel, Paul P; McManus, Michael T

    2015-01-01

    The transcription of four members of the Kunitz proteinase inhibitor (KPI) gene family of white clover (Trifolium repens L.), designated as Tr-KPI1, Tr-KPI2, Tr-KPI4 and Tr-KPI5, was investigated at both local infection (roots) and systemic (leaf tissue) sites in white clover in response to infection with the clover root knot nematode (CRKN) Meloidogyne trifoliophila and the clover cyst nematode (CCN) Heterodera trifolii. Invasion by the CRKN resulted in a significant decrease in transcript abundance of Tr-KPI4 locally at both 4 days post-infection (dpi) and at 8 dpi, and an increase in transcription of Tr-KPI1 systemically at 8 dpi. In contrast, an increase in transcript abundance of all four Tr-KPI genes locally at 4 and 8 dpi, and an increase of Tr-KPI1, Tr-KPI2, and Tr-KPI5 at 8 dpi systemically was observed in response to infection with the CCN. Challenge of a resistant (R) genotype and a susceptible (S) genotype of white clover with the CCN revealed a significant increase in transcript abundance of all four Tr-KPI genes locally in the R genotype, while an increase in abundance of only Tr-KPI1, Tr-KPI2, and Tr-KPI5 was observed in the S genotype, and only at 4 dpi. The transcript abundance of a member of the1-AMINOCYCLOPROPANE-1-CARBOXYLATE (ACC) SYNTHASE gene family from white clover (Tr-ACS1) was significantly down-regulated locally in response to CRKN infection at 4 and 8 dpi and at 4 dpi, systemically, while abundance increased locally and systemically at 8 dpi in response to CCN challenge. Conversely, the abundance of the jasmonic acid (JA) signalling gene, CORONATINE-INSENSITIVE PROTEIN 1 from white clover (Tr-COI1) increased significantly at 8 dpi locally in response to CRKN infection, but decreased at 8 dpi in response to CCN infection. The significance of this differential regulation of transcription is discussed with respect to differences in infection strategy of the two nematode species.

  8. Biotic interactions overrule plant responses to climate, depending on the species' biogeography.

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    Astrid Welk

    Full Text Available This study presents an experimental approach to assess the relative importance of climatic and biotic factors as determinants of species' geographical distributions. We asked to what extent responses of grassland plant species to biotic interactions vary with climate, and to what degree this variation depends on the species' biogeography. Using a gradient from oceanic to continental climate represented by nine common garden transplant sites in Germany, we experimentally tested whether congeneric grassland species of different geographic distribution (oceanic vs. continental plant range type responded differently to combinations of climate, competition and mollusc herbivory. We found the relative importance of biotic interactions and climate to vary between the different components of plant performance. While survival and plant height increased with precipitation, temperature had no effect on plant performance. Additionally, species with continental plant range type increased their growth in more benign climatic conditions, while those with oceanic range type were largely unable to take a similar advantage of better climatic conditions. Competition generally caused strong reductions of aboveground biomass and growth. In contrast, herbivory had minor effects on survival and growth. Against expectation, these negative effects of competition and herbivory were not mitigated under more stressful continental climate conditions. In conclusion we suggest variation in relative importance of climate and biotic interactions on broader scales, mediated via species-specific sensitivities and factor-specific response patterns. Our results have important implications for species distribution models, as they emphasize the large-scale impact of biotic interactions on plant distribution patterns and the necessity to take plant range types into account.

  9. The WRKY transcription factors in the diploid woodland strawberry Fragaria vesca: Identification and expression analysis under biotic and abiotic stresses.

    Science.gov (United States)

    Wei, Wei; Hu, Yang; Han, Yong-Tao; Zhang, Kai; Zhao, Feng-Li; Feng, Jia-Yue

    2016-08-01

    WRKY proteins comprise a large family of transcription factors that play important roles in response to biotic and abiotic stresses and in plant growth and development. To date, little is known about the WRKY gene family in strawberry. In this study, we identified 62 WRKY genes (FvWRKYs) in the wild diploid woodland strawberry (Fragaria vesca, 2n = 2x = 14) accession Heilongjiang-3. According to the phylogenetic analysis and structural features, these identified strawberry FvWRKY genes were classified into three main groups. In addition, eight FvWRKY-GFP fusion proteins showed distinct subcellular localizations in Arabidopsis mesophyll protoplasts. Furthermore, we examined the expression of the 62 FvWRKY genes in 'Heilongjiang-3' under various conditions, including biotic stress (Podosphaera aphanis), abiotic stresses (drought, salt, cold, and heat), and hormone treatments (abscisic acid, ethephon, methyl jasmonate, and salicylic acid). The expression levels of 33 FvWRKY genes were upregulated, while 12 FvWRKY genes were downregulated during powdery mildew infection. FvWRKY genes responded to drought and salt treatment to a greater extent than to temperature stress. Expression profiles derived from quantitative real-time PCR suggested that 11 FvWRKY genes responded dramatically to various stimuli at the transcriptional level, indicating versatile roles in responses to biotic and abiotic stresses. Interaction networks revealed that the crucial pathways controlled by WRKY proteins may be involved in the differential response to biotic stress. Taken together, the present work may provide the basis for future studies of the genetic modification of WRKY genes for pathogen resistance and stress tolerance in strawberry. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Transgenic crops with an improved resistance to biotic stresses. A review

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    Tohidfar, M.

    2015-01-01

    Full Text Available Introduction. Pests, diseases and weeds (biotic stresses are significant limiting factors for crop yield and production. However, the limitations associated with conventional breeding methods necessitated the development of alternative methods for improving new varieties with higher resistance to biotic stresses. Molecular techniques have developed applicable methods for genetic transformation of a wide range of plants. Genetic engineering approach has been demonstrated to provide enormous options for the selection of the resistance genes from different sources to introduce them into plants to provide resistance against different biotic stresses. Literature. In this review, we focus on strategies to achieve the above mentioned objectives including expression of insecticidal, antifungal, antibacterial, antiviral resistance and herbicide detoxification for herbicide resistance. Conclusion. Regardless of the concerns about commercialization of products from genetically modified (GM crops resistant to biotic stresses, it is observed that the cultivation area of these crops is growing fast each year. Considering this trend, it is expected that production and commercialization of GM crops resistant to biotic stresses will continue to increase but will also extend to production of crops resistant to abiotic stresses (e.g. drought, salinity, etc. in a near future.

  11. The Grape VlWRKY3 Gene Promotes Abiotic and Biotic Stress Tolerance in Transgenic Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Rongrong Guo

    2018-04-01

    Full Text Available WRKY transcription factors are known to play important roles in plant responses to various abiotic and biotic stresses. The grape WRKY gene, WRKY3 was previously reported to respond to salt and drought stress, as well as methyl jasmonate and ethylene treatments in Vitis labrusca × V. vinifera cv. ‘Kyoho.’ In the current study, WRKY3 from the ‘Kyoho’ grape cultivar was constitutively expressed in Arabidopsis thaliana under control of the cauliflower mosaic virus 35S promoter. The 35S::VlWRKY3 transgenic A. thaliana plants showed improved salt and drought stress tolerance during the germination, seedling and the mature plant stages. Various physiological traits related to abiotic stress responses were evaluated to gain further insight into the role of VlWRKY3, and it was found that abiotic stress caused less damage to the transgenic seedlings than to the wild-type (WT plants. VlWRKY3 over-expression also resulted in altered expression levels of abiotic stress-responsive genes. Moreover, the 35S::VlWRKY3 transgenic A. thaliana lines showed improved resistance to Golovinomyces cichoracearum, but increased susceptibility to Botrytis cinerea, compared with the WT plants. Collectively, these results indicate that VlWRKY3 plays important roles in responses to both abiotic and biotic stress, and modification of its expression may represent a strategy to enhance stress tolerance in crops.

  12. Genetics and regulation of combined abiotic and biotic stress tolerance in tomato

    NARCIS (Netherlands)

    Kissoudis, C.

    2016-01-01

    Projections on the impact of climate change on agricultural productivity foresee prolonged and/or increased stress intensities and enlargement of a significant number of pathogens habitats. This significantly raises the occurrence probability of (new) abiotic and biotic stress combinations. With

  13. Unraveling aspects of Bacillus amyloliquefaciens mediated enhanced production of rice under biotic stress of Rhizoctonia solani

    Directory of Open Access Journals (Sweden)

    Suchi eSrivastava

    2016-05-01

    Full Text Available Rhizoctonia solani (RS is a necrotrophic fungi causing sheath blight in rice leading to substantial loss in yield. Excessive and persistent use of preventive chemicals raises human health and environment safety concerns. As an alternative, use of biocontrol agents is highly recommended. In the present study an abiotic stress tolerant, plant growth promoting rhizobacteria Bacillus amyloliquefaciens (SN13 is demonstrated to act as a biocontrol agent and enhance immune response against RS in rice by modulating various physiological, metabolic and molecular functions. A sustained tolerance by SN13 primed plant over a longer period of time, post RS infection may be attributed to several unconventional aspects of the plants’ physiological status. The prolonged stress tolerance observed in presence of SN13 is characterized by (a involvement of bacterial mycolytic enzymes, (b sustained maintenance of elicitors to keep the immune system induced involving non-metabolizable sugars such as turanose besides the known elicitors, (c a delicate balance of ROS and ROS scavengers through production of proline, mannitol and arabitol and rare sugars like fructopyranose, β-d glucopyranose and myoinositol and expression of ferric reductases and hypoxia induced proteins, (d production of metabolites like quinozoline and expression of terpene synthase and (e hormonal cross talk. As the novel aspect of biological control this study highlights the role of rare sugars, maintenance of hypoxic conditions, and sucrose and starch metabolism in Bacillus amyloliquifaciens (SN13 mediated sustained biotic stress tolerance in rice.

  14. Using biotechnology and genomics to improve biotic and abiotic stress in apple

    Science.gov (United States)

    Genomic sequencing, molecular biology, and transformation technologies are providing valuable tools to better understand the complexity of how plants develop, function, and respond to biotic and abiotic stress. These approaches should complement but not replace a solid understanding of whole plant ...

  15. Early biotic stress detection in tomato (Solanum lycopersicum) by BVOC emissions.

    Science.gov (United States)

    Kasal-Slavik, Tina; Eschweiler, Julia; Kleist, Einhard; Mumm, Roland; Goldbach, Heiner E; Schouten, Alexander; Wildt, Jürgen

    2017-12-01

    We investigated impacts of early and mild biotic stress on Biogenic Volatile Organic Compounds (BVOC) emissions from tomato in order to test their potential for early (biotic) stress detection. Tomato plants were exposed to two common fungal pathogens, Botrytis cinerea and Oidium neolycopesici and the sap-sucking aphid Myzus persicae. Furthermore, plants were exposed to methyl jasmonate (MeJA) in order to identify BVOC emissions related to activation of jasmonic acid (JA) signalling pathway. These emissions where then used as a reference for identifying active JA signalling pathway in plants at early stages of biotic stress. After infection by the necrotrophic fungus B. cinerea, changes in BVOC emissions indicated that tomato plants had predominantly activated the jasmonic acid (JA) signalling pathway. The plants were able to modify their defence pathways in order to overcome fungal infection. When tomato plants were infected with the biotrophic fungus O. neolycopersici, only minor changes in BVOC emissions were observed with additional emissions of the sesquiterpene α-copaene. α-copaene emissions allowed the identification of general biotic stress in the plants, without pinpointing the actual triggered defence pathway. BVOC emissions during M. persicae attack had changed before the occurrence of visual symptoms. Despite low infestation rates, plants emitted methyl salicylate indicating activation of the SA-mediated defence pathway. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Utilizing genetic resources and precision agriculture to enhance resistance to biotic and abiotic stress in watermelon

    Science.gov (United States)

    Originally from Africa, watermelon is a staple crop in South Carolina and rich source of important phytochemicals that promote human health. As a result of many years of domestication and selection for desired fruit quality, modern watermelon cultivars are susceptible to biotic and abiotic stress. T...

  17. Induced Systemic Tolerance to Multiple Stresses Including Biotic and Abiotic Factors by Rhizobacteria

    Directory of Open Access Journals (Sweden)

    Sung-Je Yoo

    2017-06-01

    Full Text Available Recently, global warming and drastic climate change are the greatest threat to the world. The climate change can affect plant productivity by reducing plant adaptation to diverse environments including frequent high temperature; worsen drought condition and increased pathogen transmission and infection. Plants have to survive in this condition with a variety of biotic (pathogen/pest attack and abiotic stress (salt, high/low temperature, drought. Plants can interact with beneficial microbes including plant growth-promoting rhizobacteria, which help plant mitigate biotic and abiotic stress. This overview presents that rhizobacteria plays an important role in induced systemic resistance (ISR to biotic stress or induced systemic tolerance (IST to abiotic stress condition; bacterial determinants related to ISR and/or IST. In addition, we describe effects of rhizobacteria on defense/tolerance related signal pathway in plants. We also review recent information including plant resistance or tolerance against multiple stresses (bioticabiotic. We desire that this review contribute to expand understanding and knowledge on the microbial application in a constantly varying agroecosystem, and suggest beneficial microbes as one of alternative environment-friendly application to alleviate multiple stresses.

  18. Recommended Reference Genes for Quantitative PCR Analysis in Soybean Have Variable Stabilities during Diverse Biotic Stresses.

    Directory of Open Access Journals (Sweden)

    Raman Bansal

    Full Text Available For real-time reverse transcription-PCR (qRT-PCR in soybean, reference genes in different tissues, developmental stages, various cultivars, and under stress conditions have been suggested but their usefulness for research on soybean under various biotic stresses occurring in North-Central U.S. is not known. Here, we investigated the expression stabilities of ten previously recommended reference genes (ABCT, CYP, EF1A, FBOX, GPDH, RPL30, TUA4, TUB4, TUA5, and UNK2 in soybean under biotic stress from Bean pod mottle virus (BPMV, powdery mildew (PMD, soybean aphid (SBA, and two-spotted spider mite (TSSM. BPMV, PMD, SBA, and TSSM are amongst the most common pest problems on soybean in North-Central U.S. and other regions. Reference gene stability was determined using three software algorithms (geNorm, NormFinder, BestKeeper and a web-based tool (RefFinder. Reference genes showed variability in their expression as well as stability across various stressors and the best reference genes were stress-dependent. ABCT and FBOX were found to be the most stable in soybean under both BPMV and SBA stress but these genes had only minimal to moderate stability during PMD and TSSM stress. Expression of TUA4 and CYP was found to be most stable during PMD stress; TUB4 and TUA4 were stable under TSSM stress. Under various biotic stresses on soybean analyzed, GPDH expression was found to be consistently unstable. For all biotic stressors on soybean, we obtained pairwise variation (V2/3 values less than 0.15 which suggested that combined use of the two most stable reference genes would be sufficient for normalization. Further, we demonstrated the utility of normalizing the qRT-PCR data for target genes using the most stable reference genes validated in current study. Following of the recommendations from our current study will enable an accurate and reliable normalization of qRT-PCR data in soybean under biotic stress.

  19. Transgenic plants: resistance to abiotic and biotic stresses

    Directory of Open Access Journals (Sweden)

    Akila Wijerathna-Yapa

    2017-06-01

    Full Text Available Today’s crop breeding combined with improved agricultural management has brought substantial increases in food production. But irrigation, fertilizers pest management requires a high energy input that creates a drain on the already scare fossil fuels. It is thus clear that different strategy has to be adopted to increase crop productivity further to meet the needs of rapidly increasing world population. Crop breeders are endeavoring to meet this challenge by developing crops with higher yield, better resistance to pest, disease and weedicides, tolerance to various stress conditions.

  20. Overexpression of a Pathogenesis-Related Protein 10 Enhances Biotic and Abiotic Stress Tolerance in Rice

    Directory of Open Access Journals (Sweden)

    Jingni Wu

    2016-12-01

    Full Text Available Pathogenesis-related proteins play multiple roles in plant development and biotic and abiotic stress tolerance. Here, we characterize a rice defense related gene named “jasmonic acid inducible pathogenesis-related class 10” (JIOsPR10 to gain an insight into its functional properties. Semi-quantitative RT-PCR analysis showed up-regulation of JIOsPR10 under salt and drought stress conditions. Constitutive over-expression JIOsPR10 in rice promoted shoot and root development in transgenic plants, however, their productivity was unaltered. Further experiments exhibited that the transgenic plants showed reduced susceptibility to rice blast fungus, and enhanced salt and drought stress tolerance as compared to the wild type. A comparative proteomic profiling of wild type and transgenic plants showed that overexpression of JIOsPR10 led to the differential modulation of several proteins mainly related with oxidative stresses, carbohydrate metabolism, and plant defense. Taken together, our findings suggest that JIOsPR10 plays important roles in biotic and abiotic stresses tolerance probably by activation of stress related proteins.

  1. Understanding the Posttranscriptional Regulation of Plant Responses to Abiotic Stress

    KAUST Repository

    Alshareef, Sahar

    2017-01-01

    Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and biotic and abiotic stresses

  2. Development of a Wireless Computer Vision Instrument to Detect Biotic Stress in Wheat

    Directory of Open Access Journals (Sweden)

    Joaquin J. Casanova

    2014-09-01

    Full Text Available Knowledge of crop abiotic and biotic stress is important for optimal irrigation management. While spectral reflectance and infrared thermometry provide a means to quantify crop stress remotely, these measurements can be cumbersome. Computer vision offers an inexpensive way to remotely detect crop stress independent of vegetation cover. This paper presents a technique using computer vision to detect disease stress in wheat. Digital images of differentially stressed wheat were segmented into soil and vegetation pixels using expectation maximization (EM. In the first season, the algorithm to segment vegetation from soil and distinguish between healthy and stressed wheat was developed and tested using digital images taken in the field and later processed on a desktop computer. In the second season, a wireless camera with near real-time computer vision capabilities was tested in conjunction with the conventional camera and desktop computer. For wheat irrigated at different levels and inoculated with wheat streak mosaic virus (WSMV, vegetation hue determined by the EM algorithm showed significant effects from irrigation level and infection. Unstressed wheat had a higher hue (118.32 than stressed wheat (111.34. In the second season, the hue and cover measured by the wireless computer vision sensor showed significant effects from infection (p = 0.0014, as did the conventional camera (p < 0.0001. Vegetation hue obtained through a wireless computer vision system in this study is a viable option for determining biotic crop stress in irrigation scheduling. Such a low-cost system could be suitable for use in the field in automated irrigation scheduling applications.

  3. Biotic Stress Shifted Structure and Abundance of Enterobacteriaceae in the Lettuce Microbiome

    Science.gov (United States)

    Erlacher, Armin; Cardinale, Massimiliano; Grube, Martin; Berg, Gabriele

    2015-01-01

    Lettuce cultivars are not only amongst the most popular vegetables eaten raw, they are also involved in severe pathogen outbreaks world-wide. While outbreaks caused by Enterobacteriaceae species are well-studied, less is known about their occurrence in natural environments as well as the impact of biotic stress. Here, we studied the ecology of the human health-relevant bacterial family Enterobacteriaceae and assessed the impact of biotic disturbances by a soil-borne phytopathogenic fungus and Gastropoda on their structure and abundance in mesocosm and pot experiments. Using a polyphasic approach including network analyses of 16S rRNA gene amplicon libraries, quantitative PCR and complementary fluorescence in situ hybridization (FISH) microscopy we found substantial yet divergent Enterobacteriaceae communities. A similar spectrum of 14 genera was identified from rhizo- and phyllospheres but the abundance of Enterobacteriaceae was on average 3fold higher in phyllosphere samples. Both stress factors shifted the bacterial community of the leaf habitat, characterized by increases of species abundance and diversity. For the rhizosphere, we observed significant structural shifts of Enterobacteriaceae communities but also a high degree of resilience. These results could be confirmed by FISH microscopy but it was difficult to visualize phyllosphere communities. Additional inoculation experiments with Escherichia coli as model revealed their presence below the wax layer as well as in the endosphere of leaves. The observed presence influenced by stress factors and the endophytic life style of Enterobacteriaceae on lettuce can be an important aspect in relation to human health. PMID:25714833

  4. Biotic stress shifted structure and abundance of Enterobacteriaceae in the lettuce microbiome.

    Science.gov (United States)

    Erlacher, Armin; Cardinale, Massimiliano; Grube, Martin; Berg, Gabriele

    2015-01-01

    Lettuce cultivars are not only amongst the most popular vegetables eaten raw, they are also involved in severe pathogen outbreaks world-wide. While outbreaks caused by Enterobacteriaceae species are well-studied, less is known about their occurrence in natural environments as well as the impact of biotic stress. Here, we studied the ecology of the human health-relevant bacterial family Enterobacteriaceae and assessed the impact of biotic disturbances by a soil-borne phytopathogenic fungus and Gastropoda on their structure and abundance in mesocosm and pot experiments. Using a polyphasic approach including network analyses of 16S rRNA gene amplicon libraries, quantitative PCR and complementary fluorescence in situ hybridization (FISH) microscopy we found substantial yet divergent Enterobacteriaceae communities. A similar spectrum of 14 genera was identified from rhizo- and phyllospheres but the abundance of Enterobacteriaceae was on average 3fold higher in phyllosphere samples. Both stress factors shifted the bacterial community of the leaf habitat, characterized by increases of species abundance and diversity. For the rhizosphere, we observed significant structural shifts of Enterobacteriaceae communities but also a high degree of resilience. These results could be confirmed by FISH microscopy but it was difficult to visualize phyllosphere communities. Additional inoculation experiments with Escherichia coli as model revealed their presence below the wax layer as well as in the endosphere of leaves. The observed presence influenced by stress factors and the endophytic life style of Enterobacteriaceae on lettuce can be an important aspect in relation to human health.

  5. Biotic stress shifted structure and abundance of Enterobacteriaceae in the lettuce microbiome.

    Directory of Open Access Journals (Sweden)

    Armin Erlacher

    Full Text Available Lettuce cultivars are not only amongst the most popular vegetables eaten raw, they are also involved in severe pathogen outbreaks world-wide. While outbreaks caused by Enterobacteriaceae species are well-studied, less is known about their occurrence in natural environments as well as the impact of biotic stress. Here, we studied the ecology of the human health-relevant bacterial family Enterobacteriaceae and assessed the impact of biotic disturbances by a soil-borne phytopathogenic fungus and Gastropoda on their structure and abundance in mesocosm and pot experiments. Using a polyphasic approach including network analyses of 16S rRNA gene amplicon libraries, quantitative PCR and complementary fluorescence in situ hybridization (FISH microscopy we found substantial yet divergent Enterobacteriaceae communities. A similar spectrum of 14 genera was identified from rhizo- and phyllospheres but the abundance of Enterobacteriaceae was on average 3fold higher in phyllosphere samples. Both stress factors shifted the bacterial community of the leaf habitat, characterized by increases of species abundance and diversity. For the rhizosphere, we observed significant structural shifts of Enterobacteriaceae communities but also a high degree of resilience. These results could be confirmed by FISH microscopy but it was difficult to visualize phyllosphere communities. Additional inoculation experiments with Escherichia coli as model revealed their presence below the wax layer as well as in the endosphere of leaves. The observed presence influenced by stress factors and the endophytic life style of Enterobacteriaceae on lettuce can be an important aspect in relation to human health.

  6. Trichoderma species mediated differential tolerance against biotic stress of phytopathogens in Cicer arietinum L.

    Science.gov (United States)

    Saxena, Amrita; Raghuwanshi, Richa; Singh, Harikesh Bahadur

    2015-02-01

    Trichoderma spp. have been reported to aid in imparting biotic as well as abiotic tolerance to plants. However, there are only few reports unfolding the differential ability of separate species of Trichoderma genera generally exploited for their biocontrol potential in this framework. A study was undertaken to evaluate the biocontrol potential of different Trichoderma species namely T. harzianum, T. asperellum, T. koningiopsis, T. longibrachiatum, and T. aureoviride as identified in the group of indigenous isolates from the agricultural soils of Eastern Uttar Pradesh, India. Their biocontrol potential against three major soilborne phytopathogens, i.e., Sclerotium rolfsii, Sclerotinia sclerotiorum, and Colletotrichum capsici was confirmed by dual culture plate technique. Efficient mycoparasitic ability was further assessed in all the isolates in relation to chitinase, β-1,3 glucanase, pectinase, lipase, amylase, and cellulase production while equally consistent results were obtained for their probable phosphate solubilization and indole acetic acid (IAA) production abilities. The selected isolates were further subjected to test their ability to promote plant growth, to reduce disease incidence and to tolerate biotic stress in terms of lignification pattern against S. rolfsii in chickpea plants. Among the identified Trichoderma species, excellent results were observed for T. harzianum and T. koningiopsis indicating better biocontrol potential of these species in the group and thus exhibiting perspective for their commercial exploitation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Expression of an engineered heterologous antimicrobial peptide in potato alters plant development and mitigates normal abiotic and biotic responses.

    Directory of Open Access Journals (Sweden)

    Ravinder K Goyal

    Full Text Available Antimicrobial cationic peptides (AMPs are ubiquitous small proteins used by living cells to defend against a wide spectrum of pathogens. Their amphipathic property helps their interaction with negatively charged cellular membrane of the pathogen causing cell lysis and death. AMPs also modulate signaling pathway(s and cellular processes in animal models; however, little is known of cellular processes other than the pathogen-lysis phenomenon modulated by AMPs in plants. An engineered heterologous AMP, msrA3, expressed in potato was previously shown to cause resistance of the transgenic plants against selected fungal and bacterial pathogens. These lines together with the wild type were studied for growth habits, and for inducible defense responses during challenge with biotic (necrotroph Fusarium solani and abiotic stressors (dark-induced senescence, wounding and temperature stress. msrA3-expression not only conferred protection against F. solani but also delayed development of floral buds and prolonged vegetative phase. Analysis of select gene transcript profiles showed that the transgenic potato plants were suppressed in the hypersensitive (HR and reactive oxygen species (ROS responses to both biotic and abiotic stressors. Also, the transgenic leaves accumulated lesser amounts of the defense hormone jasmonic acid upon wounding with only a slight change in salicylic acid as compared to the wild type. Thus, normal host defense responses to the pathogen and abiotic stressors were mitigated by msrA3 expression suggesting MSRA3 regulates a common step(s of these response pathways. The stemming of the pathogen growth and mitigating stress response pathways likely contributes to resource reallocation for higher tuber yield.

  8. Utilizing genetic diversity in the desert watermelon citrullus colocynthis for enhancing watermelon cultivars for resistance to biotic and abiotic stress

    Science.gov (United States)

    Wide genetic diversity exists among the desert watermelon Citrullus colocynthis (L.) Schrad. (CC) accessions collected in the deserts of northern Africa, the Middle East, and Asia. Because of their resistance to biotic and abiotic stresses, there can be a viable source of genes used for enhancing wa...

  9. Biotic and abiotic stress tolerance in transgenic tomatoes by constitutive expression of S-adenosylmethionine decarboxylase gene.

    Science.gov (United States)

    Hazarika, Pranjal; Rajam, Manchikatla Venkat

    2011-04-01

    Recent findings have implicated the role of polyamines (putrescine, spermidine and spermine) in stress tolerance. Therefore, the present work was carried out with the goal of generating transgenic tomato plants with human S-adenosylmethionine decarboxylase (samdc) gene, a key gene involved in biosynthesis of polyamines, viz. spermidine and spermine and evaluating the transgenic plants for tolerance to both biotic and abiotic stresses. Several putative transgenic tomato plants with normal phenotype were obtained, and the transgene integration and expression was validated by PCR, Southern blot analysis and RT-PCR analysis, respectively. The transgenic plants exhibited high levels of polyamines as compared to the untransformed control plants. They also showed increased resistance against two important fungal pathogens of tomato, the wilt causing Fusarium oxysporum and the early blight causing Alternaria solani and tolerance to multiple abiotic stresses such as salinity, drought, cold and high temperature. These results suggest that engineering polyamine accumulation can confer tolerance to both biotic and abiotic stresses in plants.

  10. Effects of Abiotic and Biotic Stresses on the Internalization and Dissemination of Human Norovirus Surrogates in Growing Romaine Lettuce.

    Science.gov (United States)

    DiCaprio, Erin; Purgianto, Anastasia; Li, Jianrong

    2015-07-01

    Human norovirus (NoV) is the major causative agent of fresh-produce-related outbreaks of gastroenteritis; however, the ecology and persistence of human NoV in produce systems are poorly understood. In this study, the effects of abiotic and biotic stresses on the internalization and dissemination of two human NoV surrogates (murine norovirus 1 [MNV-1] and Tulane virus [TV]) in romaine lettuce were determined. To induce abiotic stress, romaine lettuce was grown under drought and flood conditions that mimic extreme weather events, followed by inoculation of soil with MNV-1 or TV. Independently, lettuce plants were infected with lettuce mosaic virus (LMV) to induce biotic stress, followed by inoculation with TV. Plants were grown for 14 days, and viral titers in harvested tissues were determined by plaque assays. It was found that drought stress significantly decreased the rates of both MNV-1 and TV internalization and dissemination. In contrast, neither flood stress nor biotic stress significantly impacted viral internalization or dissemination. Additionally, the rates of TV internalization and dissemination in soil-grown lettuce were significantly higher than those for MNV-1. Collectively, these results demonstrated that (i) human NoV surrogates can be internalized via roots and disseminated to shoots and leaves of romaine lettuce grown in soil, (ii) abiotic stress (drought) but not biotic stress (LMV infection) affects the rates of viral internalization and dissemination, and (iii) the type of virus affects the efficiency of internalization and dissemination. This study also highlights the need to develop effective measures to eliminate internalized viruses in fresh produce. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Ectopic overexpression of WsSGTL1, a sterol glucosyltransferase gene in Withania somnifera, promotes growth, enhances glycowithanolide and provides tolerance to abiotic and biotic stresses.

    Science.gov (United States)

    Saema, Syed; Rahman, Laiq Ur; Singh, Ruchi; Niranjan, Abhishek; Ahmad, Iffat Zareen; Misra, Pratibha

    2016-01-01

    Overexpression of sterol glycosyltransferase (SGTL1) gene of Withania somnifera showing its involvement in glycosylation of withanolide that leads to enhanced growth and tolerance to biotic and abiotic stresses. Withania somnifera is widely used in Ayurvedic medicines for over 3000 years due to its therapeutic properties. It contains a variety of glycosylated steroids called withanosides that possess neuroregenerative, adaptogenic, anticonvulsant, immunomodulatory and antioxidant activities. The WsSGTL1 gene specific for 3β-hydroxy position has a catalytic specificity to glycosylate withanolide and sterols. Glycosylation not only stabilizes the products but also alters their physiological activities and governs intracellular distribution. To understand the functional significance and potential of WsSGTL1 gene, transgenics of W. somnifera were generated using Agrobacterium tumefaciens-mediated transformation. Stable integration and overexpression of WsSGTL1 gene were confirmed by Southern blot analysis followed by quantitative real-time PCR. The WsGTL1 transgenic plants displayed number of alterations at phenotypic and metabolic level in comparison to wild-type plants which include: (1) early and enhanced growth with leaf expansion and increase in number of stomata; (2) increased production of glycowithanolide (majorly withanoside V) and campesterol, stigmasterol and sitosterol in glycosylated forms with reduced accumulation of withanolides (withaferin A, withanolide A and withanone); (3) tolerance towards biotic stress (100 % mortality of Spodoptera litura), improved survival capacity under abiotic stress (cold stress) and; (4) enhanced recovery capacity after cold stress, as indicated by better photosynthesis performance, chlorophyll, anthocyanin content and better quenching regulation of PSI and PSII. Our data demonstrate overexpression of WsSGTL1 gene which is responsible for increase in glycosylated withanolide and sterols, and confers better growth and

  12. Review of Signal Crosstalk in Plant Stress Responses

    Science.gov (United States)

    This book was prepared to summarize the current understanding of the dynamics of plant response to biotic and abiotic stresses. The preface of the book sets the stage for the contents of the different chapters by outlining that plants defend themselves from various environmental stresses through a v...

  13. Transcriptional Profiling in Cotton Associated with Bacillus Subtilis (UFLA285) Induced Biotic-Stress Tolerance

    Science.gov (United States)

    Abstract Lint yield and quality in cotton is greatly affected by water-deficit stress. The principal aim of this study was to identify cotton genes associated metabolic pathways involved in the water-deficit stress response. Gene expression profiles were developed for leaf and root tissues subject...

  14. Inclusion of biotic stress (consumer pressure) alters predictions from the stress gradient hypothesis

    NARCIS (Netherlands)

    Smit, Christian; Rietkerk, Max; Wassen, Martin J.

    2009-01-01

    The stress gradient hypothesis (SGH) predicts a shift from net negative interactions in benign environments towards net positive in harsh environments in ecological communities. While several studies found support for the SGH, others found evidence against it, leading to a debate on how nature and

  15. Release of proteins from intact chloroplasts induced by reactive oxygen species during biotic and abiotic stress.

    Science.gov (United States)

    Kwon, Kwang-Chul; Verma, Dheeraj; Jin, Shuangxia; Singh, Nameirakpam D; Daniell, Henry

    2013-01-01

    Plastids sustain life on this planet by providing food, feed, essential biomolecules and oxygen. Such diverse metabolic and biosynthetic functions require efficient communication between plastids and the nucleus. However, specific factors, especially large molecules, released from plastids that regulate nuclear genes have not yet been fully elucidated. When tobacco and lettuce transplastomic plants expressing GFP within chloroplasts, were challenged with Erwinia carotovora (biotic stress) or paraquat (abiotic stress), GFP was released into the cytoplasm. During this process GFP moves gradually towards the envelope, creating a central red zone of chlorophyll fluorescence. GFP was then gradually released from intact chloroplasts into the cytoplasm with an intact vacuole and no other visible cellular damage. Different stages of GFP release were observed inside the same cell with a few chloroplasts completely releasing GFP with detection of only red chlorophyll fluorescence or with no reduction in GFP fluorescence or transitional steps between these two phases. Time lapse imaging by confocal microscopy clearly identified sequence of these events. Intactness of chloroplasts during this process was evident from chlorophyll fluorescence emanated from thylakoid membranes and in vivo Chla fluorescence measurements (maximum quantum yield of photosystem II) made before or after infection with pathogens to evaluate their photosynthetic competence. Hydrogen peroxide and superoxide anion serve as signal molecules for generation of reactive oxygen species and Tiron, scavenger of superoxide anion, blocked release of GFP from chloroplasts. Significant increase in ion leakage in the presence of paraquat and light suggests changes in the chloroplast envelope to facilitate protein release. Release of GFP-RC101 (an antimicrobial peptide), which was triggered by Erwinia infection, ceased after conferring protection, further confirming this export phenomenon. These results suggest a

  16. Release of proteins from intact chloroplasts induced by reactive oxygen species during biotic and abiotic stress.

    Directory of Open Access Journals (Sweden)

    Kwang-Chul Kwon

    Full Text Available Plastids sustain life on this planet by providing food, feed, essential biomolecules and oxygen. Such diverse metabolic and biosynthetic functions require efficient communication between plastids and the nucleus. However, specific factors, especially large molecules, released from plastids that regulate nuclear genes have not yet been fully elucidated. When tobacco and lettuce transplastomic plants expressing GFP within chloroplasts, were challenged with Erwinia carotovora (biotic stress or paraquat (abiotic stress, GFP was released into the cytoplasm. During this process GFP moves gradually towards the envelope, creating a central red zone of chlorophyll fluorescence. GFP was then gradually released from intact chloroplasts into the cytoplasm with an intact vacuole and no other visible cellular damage. Different stages of GFP release were observed inside the same cell with a few chloroplasts completely releasing GFP with detection of only red chlorophyll fluorescence or with no reduction in GFP fluorescence or transitional steps between these two phases. Time lapse imaging by confocal microscopy clearly identified sequence of these events. Intactness of chloroplasts during this process was evident from chlorophyll fluorescence emanated from thylakoid membranes and in vivo Chla fluorescence measurements (maximum quantum yield of photosystem II made before or after infection with pathogens to evaluate their photosynthetic competence. Hydrogen peroxide and superoxide anion serve as signal molecules for generation of reactive oxygen species and Tiron, scavenger of superoxide anion, blocked release of GFP from chloroplasts. Significant increase in ion leakage in the presence of paraquat and light suggests changes in the chloroplast envelope to facilitate protein release. Release of GFP-RC101 (an antimicrobial peptide, which was triggered by Erwinia infection, ceased after conferring protection, further confirming this export phenomenon. These

  17. ZmGns, a maize class I b-1,3-glucanase, is induced by biotic stresses and possesses strong antimicrobial activity

    Institute of Scientific and Technical Information of China (English)

    Yu-Rong Xie; Yenjit Raruang; Zhi-Yuan Chen; Robert L Brown; Thomas E Cleveland

    2015-01-01

    Plant b‐1,3‐glucanases are members of the patho-genesis‐related protein 2 (PR‐2) family, which is one of the 17 PR protein families and plays important roles in biotic and abiotic stress responses. One of the differential y expressed proteins (spot 842) identified in a recent proteomic comparison between five pairs of closely related maize (Zea mays L.) lines differing in aflatoxin resistance was further investigated in the present study. Here, the corresponding cDNA was cloned from maize and designated as ZmGns. ZmGns encodes a protein of 338 amino acids containing a potential signal peptide. The expression of ZmGns was detectible in al tissues studied with the highest level in silks. ZmGns was significantly induced by biotic stresses including three bacteria and the fungus Aspergillus flavus. ZmGns was also induced by most abiotic stresses tested and growth hormones including salicylic acid. In vivo, ZmGns showed a significant inhibitory activity against the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 and fungal pathogen Botrytis cinerea when it overexpressed in Arabidopsis. Its high level of expression in the silk tissue and its induced expression by phytohormone treatment, as wel as by bacterial and fungal infections, suggest it plays a complex role in maize growth, development, and defense.

  18. Separating the role of biotic interactions and climate in determining adaptive response of plants to climate change.

    Science.gov (United States)

    Tomiolo, Sara; Van der Putten, Wim H; Tielbörger, Katja

    2015-05-01

    Altered rainfall regimes will greatly affect the response of plant species to climate change. However, little is known about how direct effects of changing precipitation on plant performance may depend on other abiotic factors and biotic interactions. We used reciprocal transplants between climatically very different sites with simultaneous manipulation of soil, plant population origin, and neighbor conditions to evaluate local adaptation and possible adaptive response of four Eastern Mediterranean annual plant species to climate change. The effect of site on plant performance was negligible, but soil origin had a strong effect on fecundity, most likely due to differential water retaining ability. Competition by neighbors strongly reduced fitness. We separated the effects of the abiotic and biotic soil properties on plant performance by repeating the field experiment in a greenhouse under homogenous environmental conditions and including a soil biota manipulation treatment. As in the field, plant performance differed among soil origins and neighbor treatments. Moreover, we found plant species-specific responses to soil biota that may be best explained by the differential sensitivity to negative and positive soil biota effects. Overall, under the conditions of our experiment with two contrasting sites, biotic interactions had a strong effect on plant fitness that interacted with and eventually overrode climate. Because climate and biotic interactions covary, reciprocal transplants and climate gradient studies should consider soil biotic interactions and abiotic conditions when evaluating climate change effects on plant performance.

  19. Alternative Oxidase: A Mitochondrial Respiratory Pathway to Maintain Metabolic and Signaling Homeostasis during Abiotic and Biotic Stress in Plants

    Directory of Open Access Journals (Sweden)

    Greg C. Vanlerberghe

    2013-03-01

    Full Text Available Alternative oxidase (AOX is a non-energy conserving terminal oxidase in the plant mitochondrial electron transport chain. While respiratory carbon oxidation pathways, electron transport, and ATP turnover are tightly coupled processes, AOX provides a means to relax this coupling, thus providing a degree of metabolic homeostasis to carbon and energy metabolism. Beside their role in primary metabolism, plant mitochondria also act as “signaling organelles”, able to influence processes such as nuclear gene expression. AOX activity can control the level of potential mitochondrial signaling molecules such as superoxide, nitric oxide and important redox couples. In this way, AOX also provides a degree of signaling homeostasis to the organelle. Evidence suggests that AOX function in metabolic and signaling homeostasis is particularly important during stress. These include abiotic stresses such as low temperature, drought, and nutrient deficiency, as well as biotic stresses such as bacterial infection. This review provides an introduction to the genetic and biochemical control of AOX respiration, as well as providing generalized examples of how AOX activity can provide metabolic and signaling homeostasis. This review also examines abiotic and biotic stresses in which AOX respiration has been critically evaluated, and considers the overall role of AOX in growth and stress tolerance.

  20. Genome-wide identification and analysis of biotic and abiotic stress regulation of small heat shock protein (HSP20) family genes in bread wheat.

    Science.gov (United States)

    Muthusamy, Senthilkumar K; Dalal, Monika; Chinnusamy, Viswanathan; Bansal, Kailash C

    2017-04-01

    Small Heat Shock Proteins (sHSPs)/HSP20 are molecular chaperones that protect plants by preventing protein aggregation during abiotic stress conditions, especially heat stress. Due to global climate change, high temperature is emerging as a major threat to wheat productivity. Thus, the identification of HSP20 and analysis of HSP transcriptional regulation under different abiotic stresses in wheat would help in understanding the role of these proteins in abiotic stress tolerance. We used sequences of known rice and Arabidopsis HSP20 HMM profiles as queries against publicly available wheat genome and wheat full length cDNA databases (TriFLDB) to identify the respective orthologues from wheat. 163 TaHSP20 (including 109 sHSP and 54 ACD) genes were identified and classified according to the sub-cellular localization and phylogenetic relationship with sequenced grass genomes (Oryza sativa, Sorghum bicolor, Zea mays, Brachypodium distachyon and Setaria italica). Spatio-temporal, biotic and abiotic stress-specific expression patterns in normalized RNA seq and wheat array datasets revealed constitutive as well as inductive responses of HSP20 in different tissues and developmental stages of wheat. Promoter analysis of TaHSP20 genes showed the presence of tissue-specific, biotic, abiotic, light-responsive, circadian and cell cycle-responsive cis-regulatory elements. 14 TaHSP20 family genes were under the regulation of 8 TamiRNA genes. The expression levels of twelve HSP20 genes were studied under abiotic stress conditions in the drought- and heat-tolerant wheat genotype C306. Of the 13 TaHSP20 genes, TaHSP16.9H-CI showed high constitutive expression with upregulation only under salt stress. Both heat and salt stresses upregulated the expression of TaHSP17.4-CI, TaHSP17.7A-CI, TaHSP19.1-CIII, TaACD20.0B-CII and TaACD20.6C-CIV, while TaHSP23.7-MTI was specifically induced only under heat stress. Our results showed that the identified TaHSP20 genes play an important role under

  1. Abiotic and biotic factors responsible for antimonite oxidation in Agrobacterium tumefaciens GW4

    Science.gov (United States)

    Li, Jingxin; Yang, Birong; Shi, Manman; Yuan, Kai; Guo, Wei; Wang, Qian; Wang, Gejiao

    2017-03-01

    Antimonite [Sb(III)]-oxidizing bacteria can transform the toxic Sb(III) into the less toxic antimonate [Sb(V)]. Recently, the cytoplasmic Sb(III)-oxidase AnoA and the periplasmic arsenite [As(III)] oxidase AioAB were shown to responsible for bacterial Sb(III) oxidation, however, disruption of each gene only partially decreased Sb(III) oxidation efficiency. This study showed that in Agrobacterium tumefaciens GW4, Sb(III) induced cellular H2O2 content and H2O2 degradation gene katA. Gene knock-out/complementation of katA, anoA, aioA and anoA/aioA and Sb(III) oxidation and growth experiments showed that katA, anoA and aioA were essential for Sb(III) oxidation and resistance and katA was also essential for H2O2 resistance. Furthermore, linear correlations were observed between cellular H2O2 and Sb(V) content in vivo and chemical H2O2 and Sb(V) content in vitro (R2 = 0.93 and 0.94, respectively). These results indicate that besides the biotic factors, the cellular H2O2 induced by Sb(III) also catalyzes bacterial Sb(III) oxidation as an abiotic oxidant. The data reveal a novel mechanism that bacterial Sb(III) oxidation is associated with abiotic (cellular H2O2) and biotic (AnoA and AioAB) factors and Sb(III) oxidation process consumes cellular H2O2 which contributes to microbial detoxification of both Sb(III) and cellular H2O2.

  2. Ground-based hyperspectral remote sensing to discriminate biotic stress in cotton crop

    Science.gov (United States)

    Nigam, Rahul; Kot, Rajsi; Sandhu, Sandeep S.; Bhattacharya, Bimal K.; Chandi, Ravinder S.; Singh, Manjeet; Singh, Jagdish; Manjunath, K. R.

    2016-05-01

    A large gap exists between the potential yield and the yield realized at the agricultural field. Among the factors contributing towards this yield gap are the biotic stresses that affect the crops growth and development. Severity of infestation of the pests and diseases differs between agroclimatic region, individual crops and seasons within a region. Information about the timing of start of infestation of these diseases and pests with their gradual progress in advance could enable plan necessary pesticide schedule for the season, region on the particular crop against the specific menace expected. This could be enabled by development of region, crop and pest-specific prediction models to forewarn these menaces. In India most (70%) of the land-holding size of farmers average 0.39 ha (some even 20 m x 20 m) and only 1% crop growers holdproblems in its proper assessment and management. Thus, such exercise could be highly time-consuming and labour-intensive for the seventh largest country with difficult terrain, 66% gross cropped area under food crops, lacking in number of skilled manpower and shrinking resources. Remote sensing overcomes such limitations with ability to access all parts of the country and can often achieve a high spatial, temporal and spectral resolution and thus leading to an accurate estimation of area affected. Due to pest and disease stress plants showed different behavior in terms of physiological and morphological changes lead to symptoms such as wilting, curling of leaf, stunned growth, reduction in leaf area due to severe defoliation or chlorosis or necrosis of photosynthetically active parts (Prabhakar et al., 2011; Booteet al., 1983; Aggarwal et al., 2006). Damage evaluation of diseases has been largely done by visual inspections and quantification but visual quantification of plant pest and diseases with accuracy and precision is a tough task. Utilization of remote sensing techniques are based on the assumption that plant pest and disease

  3. Anion channels: master switches of stress responses.

    Science.gov (United States)

    Roelfsema, M Rob G; Hedrich, Rainer; Geiger, Dietmar

    2012-04-01

    During stress, plant cells activate anion channels and trigger the release of anions across the plasma membrane. Recently, two new gene families have been identified that encode major groups of anion channels. The SLAC/SLAH channels are characterized by slow voltage-dependent activation (S-type), whereas ALMT genes encode rapid-activating channels (R-type). Both S- and R-type channels are stimulated in guard cells by the stress hormone ABA, which leads to stomatal closure. Besides their role in ABA-dependent stomatal movement, anion channels are also activated by biotic stress factors such as microbe-associated molecular patterns (MAMPs). Given that anion channels occur throughout the plant kingdom, they are likely to serve a general function as master switches of stress responses. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. GhWRKY25, a group I WRKY gene from cotton, confers differential tolerance to abiotic and biotic stresses in transgenic Nicotiana benthamiana.

    Science.gov (United States)

    Liu, Xiufang; Song, Yunzhi; Xing, Fangyu; Wang, Ning; Wen, Fujiang; Zhu, Changxiang

    2016-09-01

    WRKY transcription factors are involved in various processes, ranging from plant growth to abiotic and biotic stress responses. Group I WRKY members have been rarely reported compared with group II or III members, particularly in cotton (Gossypium hirsutum). In this study, a group I WRKY gene, namely, GhWRKY25, was cloned from cotton and characterized. Expression analysis revealed that GhWRKY25 can be induced or deduced by the treatments of abiotic stresses and multiple defense-related signaling molecules. Overexpression of GhWRKY25 in Nicotiana benthamiana reduced plant tolerance to drought stress but enhanced tolerance to salt stress. Moreover, more MDA and ROS accumulated in transgenic plants after drought treatment with lower activities of SOD, POD, and CAT. Our study further demonstrated that GhWRKY25 overexpression in plants enhanced sensitivity to the fungal pathogen Botrytis cinerea by reducing the expression of SA or ET signaling related genes and inducing the expression of genes involved in the JA signaling pathway. These results indicated that GhWRKY25 plays negative or positive roles in response to abiotic stresses, and the reduced pathogen resistance may be related to the crosstalk of the SA and JA/ET signaling pathways.

  5. WRKY transcription factors in plant responses to stresses.

    Science.gov (United States)

    Jiang, Jingjing; Ma, Shenghui; Ye, Nenghui; Jiang, Ming; Cao, Jiashu; Zhang, Jianhua

    2017-02-01

    The WRKY gene family is among the largest families of transcription factors (TFs) in higher plants. By regulating the plant hormone signal transduction pathway, these TFs play critical roles in some plant processes in response to biotic and abiotic stress. Various bodies of research have demonstrated the important biological functions of WRKY TFs in plant response to different kinds of biotic and abiotic stresses and working mechanisms. However, very little summarization has been done to review their research progress. Not just important TFs function in plant response to biotic and abiotic stresses, WRKY also participates in carbohydrate synthesis, senescence, development, and secondary metabolites synthesis. WRKY proteins can bind to W-box (TGACC (A/T)) in the promoter of its target genes and activate or repress the expression of downstream genes to regulate their stress response. Moreover, WRKY proteins can interact with other TFs to regulate plant defensive responses. In the present review, we focus on the structural characteristics of WRKY TFs and the research progress on their functions in plant responses to a variety of stresses. © 2016 Institute of Botany, Chinese Academy of Sciences.

  6. High CO2 Primes Plant Biotic Stress Defences through Redox-Linked Pathways.

    Science.gov (United States)

    Mhamdi, Amna; Noctor, Graham

    2016-10-01

    Industrial activities have caused tropospheric CO 2 concentrations to increase over the last two centuries, a trend that is predicted to continue for at least the next several decades. Here, we report that growth of plants in a CO 2 -enriched environment activates responses that are central to defense against pathogenic attack. Salicylic acid accumulation was triggered by high-growth CO 2 in Arabidopsis (Arabidopsis thaliana) and other plants such as bean (Phaseolus vulgaris). A detailed analysis in Arabidopsis revealed that elevated CO 2 primes multiple defense pathways, leading to increased resistance to bacterial and fungal challenge. Analysis of gene-specific mutants provided no evidence that activation of plant defense pathways by high CO 2 was caused by stomatal closure. Rather, the activation is partly linked to metabolic effects involving redox signaling. In support of this, genetic modification of redox components (glutathione contents and NADPH-generating enzymes) prevents full priming of the salicylic acid pathway and associated resistance by high CO 2 The data point to a particularly influential role for the nonphosphorylating glyceraldehyde-3-phosphate dehydrogenase, a cytosolic enzyme whose role in plants remains unclear. Our observations add new information on relationships between high CO 2 and oxidative signaling and provide novel insight into plant stress responses in conditions of increased CO 2 . © 2016 American Society of Plant Biologists. All Rights Reserved.

  7. Biotic stress protein markers of Aquilaria sp. for gaharu species identification in Malaysia

    International Nuclear Information System (INIS)

    Azhar Mohamad; Abdul Rahim Harun

    2012-01-01

    Gaharu trees (Aquilaria) is in danger of extinction in the wild due to illegal logging. Its resin (Gaharu) is used for the production of highly valued incense throughout Asia. In Aquilaria sp. systemic induction of defense genes in response to mechanical wounding in nature is regulated by an 18-amino-acid peptide signal protein called systemin. This protein is produced in response to the natural stress at the vicinity of the wound and is also influenced by its genetic background. As the protein can be differentiated by its locality, the protein expressed is also found to be significantly different which, in turn, can be used for identification of this plant species. In this work, A. malaccensis and A. hirta were evaluated based on the targeted genes related to systemin. Targeted gene refers to specific sequence in genomic DNA. Sequence mining from public databases is part of the crucial process in getting the specific genes. The sequences will go through alignment step to identify conserved region prior to primer design. The primers were used in Polymerase Chain Reaction (PCR) techniques to amplify the conserved regions. It was found that both samples can be differentiated. This would be useful for plant breeders, trader and planter in ensuring authentic planting materials. This paper will describe the use of targeted genes primers as markers in identifying the Aquilaria species. (author)

  8. High CO2 Primes Plant Biotic Stress Defences through Redox-Linked Pathways1[OPEN

    Science.gov (United States)

    2016-01-01

    Industrial activities have caused tropospheric CO2 concentrations to increase over the last two centuries, a trend that is predicted to continue for at least the next several decades. Here, we report that growth of plants in a CO2-enriched environment activates responses that are central to defense against pathogenic attack. Salicylic acid accumulation was triggered by high-growth CO2 in Arabidopsis (Arabidopsis thaliana) and other plants such as bean (Phaseolus vulgaris). A detailed analysis in Arabidopsis revealed that elevated CO2 primes multiple defense pathways, leading to increased resistance to bacterial and fungal challenge. Analysis of gene-specific mutants provided no evidence that activation of plant defense pathways by high CO2 was caused by stomatal closure. Rather, the activation is partly linked to metabolic effects involving redox signaling. In support of this, genetic modification of redox components (glutathione contents and NADPH-generating enzymes) prevents full priming of the salicylic acid pathway and associated resistance by high CO2. The data point to a particularly influential role for the nonphosphorylating glyceraldehyde-3-phosphate dehydrogenase, a cytosolic enzyme whose role in plants remains unclear. Our observations add new information on relationships between high CO2 and oxidative signaling and provide novel insight into plant stress responses in conditions of increased CO2. PMID:27578552

  9. QTLs for tolerance of drought and breeding for tolerance of abiotic and biotic stress: an integrated approach.

    Directory of Open Access Journals (Sweden)

    Shalabh Dixit

    Full Text Available BACKGROUND: The coupling of biotic and abiotic stresses leads to high yield losses in rainfed rice (Oryza sativa L. growing areas. While several studies target these stresses independently, breeding strategies to combat multiple stresses seldom exist. This study reports an integrated strategy that combines QTL mapping and phenotypic selection to develop rice lines with high grain yield (GY under drought stress and non-stress conditions, and tolerance of rice blast. METHODOLOGY: A blast-tolerant BC2F3-derived population was developed from the cross of tropical japonica cultivar Moroberekan (blast- and drought-tolerant and high-yielding indica variety Swarna (blast- and drought-susceptible through phenotypic selection for blast tolerance at the BC2F2 generation. The population was studied for segregation distortion patterns and QTLs for GY under drought were identified along with study of epistatic interactions for the trait. RESULTS: Segregation distortion, in favour of Moroberekan, was observed at 50 of the 59 loci. Majority of these marker loci co-localized with known QTLs for blast tolerance or NBS-LRR disease resistance genes. Despite the presence of segregation distortion, high variation for DTF, PH and GY was observed and several QTLs were identified under drought stress and non-stress conditions for the three traits. Epistatic interactions were also detected for GY which explained a large proportion of phenotypic variance observed in the population. CONCLUSIONS: This strategy allowed us to identify QTLs for GY along with rapid development of high-yielding purelines tolerant to blast and drought with considerably reduced efforts. Apart from this, it also allowed us to study the effects of the selection cycle for blast tolerance. The developed lines were screened at IRRI and in the target environment, and drought and blast tolerant lines with high yield were identified. With tolerance to two major stresses and high yield potential, these

  10. Selected Abiotic and Biotic Environmental Stress Factors Affecting Two Economically Important Sugarcane Stalk Boring Pests in the United States

    Directory of Open Access Journals (Sweden)

    Allan T. Showler

    2016-02-01

    Full Text Available Sugarcane, Saccharum spp., in the United States is attacked by a number of different arthropod pests. The most serious among those pests are two stalk boring moths in the Family Crambidae: the sugarcane borer, Diatraea saccharalis (F., and the Mexican rice borer, Eoreuma loftini (Dyar. The two species are affected by abiotic and biotic environmental stress factors. Water deficit and excessive soil nitrogen alter physical and physiochemical aspects of the sugarcane plant that make the crop increasingly vulnerable to E. loftini. Weed growth can be competitive with sugarcane but it also supports enhanced abundances and diversity of natural enemies that can suppress infestations of D. saccharalis. In an instance where the stalk borer is considered a stress factor, proximity of vulnerable crops to sugarcane can influence levels of E. loftini infestation of sugarcane. The adverse effects of each stress factor, in terms of stalk borer attack, can be reduced by adopting appropriate cultural practices, such as adequate irrigation, judicious use of nitrogen fertilizer, using noncompetitive weed growth, and not planting vulnerable crops near sugarcane fields. Understanding the relationships between stress factors and crop pests can provide valuable insights for plant breeders and tools for incorporation into integrated pest management strategies.

  11. The phenotypic and molecular assessment of the non-conserved Arabidopsis MICRORNA163/S-ADENOSYL-METHYLTRANSFERASE regulatory module during biotic stress.

    Science.gov (United States)

    Litholdo, Celso Gaspar; Eamens, Andrew Leigh; Waterhouse, Peter Michael

    2018-04-01

    In plants, microRNAs (miRNAs) have evolved in parallel to the protein-coding genes that they target for expression regulation, and miRNA-directed gene expression regulation is central to almost every cellular process. MicroRNA, miR163, is unique to the Arabidopsis genus and is processed into a 24-nucleotide (nt) mature small regulatory RNA (sRNA) from a single precursor transcript transcribed from a single locus, the MIR163 gene. The MIR163 locus is a result of a recent inverted duplication event of one of the five closely related S-ADENOSYL-METHYLTRANSFERASE genes that the mature miR163 sRNA targets for expression regulation. Currently, however, little is known about the role of the miR163/S-ADENOSYL-METHYLTRANSFERASE regulatory module in response to biotic stress. Here, we document the expression domains of MIR163 and the S-ADENOSYL-METHYLTRANSFERASE target genes following fusion of their putative promoter sequences to the β-glucuronidase (GUS) reporter gene and subsequent in planta expression. Further, we report on our phenotypic and molecular assessment of Arabidopsis thaliana plants with altered miR163 accumulation, namely the mir163-1 and mir163-2 insertion knockout mutants and the miR163 overexpression line, the MIR163-OE plant. Finally, we reveal miR163 accumulation and S-ADENOSYL-METHYLTRANSFERASE target gene expression post treatment with the defence elicitors, salicylic acid and jasmonic acid, and following Fusarium oxysporum infection, wounding, and herbivory attack. Together, the work presented here provides a comprehensive new biological insight into the role played by the Arabidopsis genus-specific miR163/S-ADENOSYL-METHYLTRANSFERASE regulatory module in normal A. thaliana development and during the exposure of A. thaliana plants to biotic stress.

  12. Genome-Wide Characterization and Expression Analysis of Major Intrinsic Proteins during Abiotic and Biotic Stresses in Sweet Orange (Citrus sinensis L. Osb.).

    Science.gov (United States)

    Martins, Cristina de Paula Santos; Pedrosa, Andresa Muniz; Du, Dongliang; Gonçalves, Luana Pereira; Yu, Qibin; Gmitter, Frederick G; Costa, Marcio Gilberto Cardoso

    2015-01-01

    The family of aquaporins (AQPs), or major intrinsic proteins (MIPs), includes integral membrane proteins that function as transmembrane channels for water and other small molecules of physiological significance. MIPs are classified into five subfamilies in higher plants, including plasma membrane (PIPs), tonoplast (TIPs), NOD26-like (NIPs), small basic (SIPs) and unclassified X (XIPs) intrinsic proteins. This study reports a genome-wide survey of MIP encoding genes in sweet orange (Citrus sinensis L. Osb.), the most widely cultivated Citrus spp. A total of 34 different genes encoding C. sinensis MIPs (CsMIPs) were identified and assigned into five subfamilies (CsPIPs, CsTIPs, CsNIPs, CsSIPs and CsXIPs) based on sequence analysis and also on their phylogenetic relationships with clearly classified MIPs of Arabidopsis thaliana. Analysis of key amino acid residues allowed the assessment of the substrate specificity of each CsMIP. Gene structure analysis revealed that the CsMIPs possess an exon-intron organization that is highly conserved within each subfamily. CsMIP loci were precisely mapped on every sweet orange chromosome, indicating a wide distribution of the gene family in the sweet orange genome. Investigation of their expression patterns in different tissues and upon drought and salt stress treatments, as well as with 'Candidatus Liberibacter asiaticus' infection, revealed a tissue-specific and coordinated regulation of the different CsMIP isoforms, consistent with the organization of the stress-responsive cis-acting regulatory elements observed in their promoter regions. A special role in regulating the flow of water and nutrients is proposed for CsTIPs and CsXIPs during drought stress, and for most CsMIPs during salt stress and the development of HLB disease. These results provide a valuable reference for further exploration of the CsMIPs functions and applications to the genetic improvement of both abiotic and biotic stress tolerance in citrus.

  13. Genome-Wide Characterization and Expression Analysis of Major Intrinsic Proteins during Abiotic and Biotic Stresses in Sweet Orange (Citrus sinensis L. Osb..

    Directory of Open Access Journals (Sweden)

    Cristina de Paula Santos Martins

    Full Text Available The family of aquaporins (AQPs, or major intrinsic proteins (MIPs, includes integral membrane proteins that function as transmembrane channels for water and other small molecules of physiological significance. MIPs are classified into five subfamilies in higher plants, including plasma membrane (PIPs, tonoplast (TIPs, NOD26-like (NIPs, small basic (SIPs and unclassified X (XIPs intrinsic proteins. This study reports a genome-wide survey of MIP encoding genes in sweet orange (Citrus sinensis L. Osb., the most widely cultivated Citrus spp. A total of 34 different genes encoding C. sinensis MIPs (CsMIPs were identified and assigned into five subfamilies (CsPIPs, CsTIPs, CsNIPs, CsSIPs and CsXIPs based on sequence analysis and also on their phylogenetic relationships with clearly classified MIPs of Arabidopsis thaliana. Analysis of key amino acid residues allowed the assessment of the substrate specificity of each CsMIP. Gene structure analysis revealed that the CsMIPs possess an exon-intron organization that is highly conserved within each subfamily. CsMIP loci were precisely mapped on every sweet orange chromosome, indicating a wide distribution of the gene family in the sweet orange genome. Investigation of their expression patterns in different tissues and upon drought and salt stress treatments, as well as with 'Candidatus Liberibacter asiaticus' infection, revealed a tissue-specific and coordinated regulation of the different CsMIP isoforms, consistent with the organization of the stress-responsive cis-acting regulatory elements observed in their promoter regions. A special role in regulating the flow of water and nutrients is proposed for CsTIPs and CsXIPs during drought stress, and for most CsMIPs during salt stress and the development of HLB disease. These results provide a valuable reference for further exploration of the CsMIPs functions and applications to the genetic improvement of both abiotic and biotic stress tolerance in citrus.

  14. Genome-wide analysis of the grapevine stilbene synthase multigenic family: genomic organization and expression profiles upon biotic and abiotic stresses

    Directory of Open Access Journals (Sweden)

    Vannozzi Alessandro

    2012-08-01

    Full Text Available Abstract Background Plant stilbenes are a small group of phenylpropanoids, which have been detected in at least 72 unrelated plant species and accumulate in response to biotic and abiotic stresses such as infection, wounding, UV-C exposure and treatment with chemicals. Stilbenes are formed via the phenylalanine/polymalonate-route, the last step of which is catalyzed by the enzyme stilbene synthase (STS, a type III polyketide synthase (PKS. Stilbene synthases are closely related to chalcone synthases (CHS, the key enzymes of the flavonoid pathway, as illustrated by the fact that both enzymes share the same substrates. To date, STSs have been cloned from peanut, pine, sorghum and grapevine, the only stilbene-producing fruiting-plant for which the entire genome has been sequenced. Apart from sorghum, STS genes appear to exist as a family of closely related genes in these other plant species. Results In this study a complete characterization of the STS multigenic family in grapevine has been performed, commencing with the identification, annotation and phylogenetic analysis of all members and integration of this information with a comprehensive set of gene expression analyses including healthy tissues at differential developmental stages and in leaves exposed to both biotic (downy mildew infection and abiotic (wounding and UV-C exposure stresses. At least thirty-three full length sequences encoding VvSTS genes were identified, which, based on predicted amino acid sequences, cluster in 3 principal groups designated A, B and C. The majority of VvSTS genes cluster in groups B and C and are located on chr16 whereas the few gene family members in group A are found on chr10. Microarray and mRNA-seq expression analyses revealed different patterns of transcript accumulation between the different groups of VvSTS family members and between VvSTSs and VvCHSs. Indeed, under certain conditions the transcriptional response of VvSTS and VvCHS genes appears to be

  15. Bread wheat selection against abiotic and biotic stresses in highland Balochistan, Pakistan

    International Nuclear Information System (INIS)

    Begum, I.; Afzal, J.; Afzal, J.

    2008-01-01

    Bread wheat (Triticum aestivum L. ssp. aestivum) lines were screened in multi-location trials in highland Balochistan, Pakistan from 1982 (F2) to 1990 (fixed lines). Objective of the study was to select and evaluate desirable genotypes for winter planting, Of 816 entries, only four successfully passed through the observation nurseries and yield trials. After nine years of testing only genotype ICW81.1471 was selected for wide-scale agronomic testing. Although the yield potential of this genotype was not significantly higher than that of the local check, it had the important advantage of possessing good resistance to yellow rust (Puccinia striiformis West) The results showed that exposure of segregating population to the prevailing environmental stresses of cold and drought was an effective selection procedure for identifying genotypes which are resistant to such stresses. Effective selection can be made for other desirable attributes such as disease and pest resistance, plant height and time to maturity. (author)

  16. Bruxism affects stress responses in stressed rats.

    Science.gov (United States)

    Sato, Chikatoshi; Sato, Sadao; Takashina, Hirofumi; Ishii, Hidenori; Onozuka, Minoru; Sasaguri, Kenichi

    2010-04-01

    It has been proposed that suppression of stress-related emotional responses leads to the simultaneous activation of both sympathetic and parasympathetic divisions of the autonomic nervous system (ANS) and that the expression of these emotional states has a protective effect against ulcerogenesis. In the present study, we investigated whether stress-induced bruxism activity (SBA) has a physiological effect of on the stress-induced changes of the stomach, thymus, and spleen as well as blood leukocytes, cortisol, and adrenaline. This study demonstrated that SBA attenuated the stress-induced ulcer genesis as well as degenerative changes of thymus and spleen. SBA also attenuated increases of adrenaline, cortisol, and neutrophils in the blood. In conclusion, expression of aggression through SBA during stress exposure attenuates both stress-induced ANS response, including gastric ulcer formation.

  17. Multitasking antimicrobial peptides, plant development, and host defense against biotic/abiotic stress

    Science.gov (United States)

    Crop losses due to pathogens are a major threat to global food security. Plants employ a multilayer defense system against pathogens including use of physical barriers (cell wall), induction of hypersensitive defense response (HR), resistance (R) proteins, and synthesis of antimicrobial peptides (AM...

  18. Research on mutant barley population under biotic and abiotic stress condition

    International Nuclear Information System (INIS)

    Peskircioglu, H.; Tuyluer, I.; Sagel, Z.; Kunter, B.; Kantoglu, Y.

    2009-01-01

    Barley is one of the most important cereal with 8,5 million tons production, 3,5 million hectares of sowing area in Turkey which is also one of the gene centres of barley. Barley is grown in every regions of Turkey where climatic conditions are available for the crop. But barley is the predominant crop in the driest land areas throughout the Anatolian plateau. Winters on that plateau are especially severe. Summers are hot and dry with temperatures above 30 degree C. Annual precipitation averages about 300 to 400 millimeters and rains mainly in winter. Because of all of these prerequisite conditions, winter barley dominates in Turkey, which indirectly refers to water economy. According to the above mentioned reasons the objectives of this investigation were: 1) Improvement of drought resistance, loading resistance and high yielding barley varieties by mutation breeding in Central Anatolian Region. 2) Determination and selection of abiotic stress such as salt resistance In our barley mutation breeding programme under Central Anatolian conditions well adapted Tokak 157/37 variety has been used. We applied 250 Gy-300 Gy gamma ray doses . Selection began at M 2 generation. Agronomical characters including earliness, straw length, lodging resistance and disease resistance are monitored in the field and greenhouse. Mutant lines have been tested for salt resistance in the hydrophonic culture which contains 180 mMol and 220 mMol NaCl concentrations. Preliminary yield trial and advanced yield trial are started after M 4 generations. In M 6 generation, we had some desirable lines those are 25-30 days earlier than its parents, so these lines escape from drought period. Some lines that have grown in the hydrophonic cultures, contains 180mMol NaCl still surviving.

  19. Impact of phenolic compounds and related enzymes in Sorghum varieties for resistance and susceptibility to biotic and abiotic stresses

    NARCIS (Netherlands)

    Dicko, M.H.; Gruppen, H.; Barro, C.; Traore, A.S.; Berkel, van W.J.H.; Voragen, A.G.J.

    2005-01-01

    Contents of phenolic compounds and related enzymes before and after sorghum grain germination were compared between varieties either resistant or susceptible to biotic (sooty stripe, sorghum midge, leaf anthracnose, striga, and grain molds) and abiotic (lodging, drought resistance, and photoperiod

  20. Overexpression of an AP2/ERF Type Transcription Factor OsEREBP1 Confers Biotic and Abiotic Stress Tolerance in Rice.

    Directory of Open Access Journals (Sweden)

    V Jisha

    Full Text Available AP2/ERF-type transcription factors regulate important functions of plant growth and development as well as responses to environmental stimuli. A rice AP2/ERF transcription factor, OsEREBP1 is a downstream component of a signal transduction pathway in a specific interaction between rice (Oryza sativa and its bacterial pathogen, Xoo (Xanthomonas oryzae pv. oryzae. Constitutive expression of OsEREBP1 in rice driven by maize ubiquitin promoter did not affect normal plant growth. Microarray analysis revealed that over expression of OsEREBP1 caused increased expression of lipid metabolism related genes such as lipase and chloroplastic lipoxygenase as well as several genes related to jasmonate and abscisic acid biosynthesis. PR genes, transcription regulators and Aldhs (alcohol dehydrogenases implicated in abiotic stress and submergence tolerance were also upregulated in transgenic plants. Transgenic plants showed increase in endogenous levels of α-linolenate, several jasmonate derivatives and abscisic acid but not salicylic acid. Soluble modified GFP (SmGFP-tagged OsEREBP1 was localized to plastid nucleoids. Comparative analysis of non-transgenic and OsEREBP1 overexpressing genotypes revealed that OsEREBP1 attenuates disease caused by Xoo and confers drought and submergence tolerance in transgenic rice. Our results suggest that constitutive expression of OsEREBP1 activates the jasmonate and abscisic acid signalling pathways thereby priming the rice plants for enhanced survival under abiotic or biotic stress conditions. OsEREBP1 is thus, a good candidate gene for engineering plants for multiple stress tolerance.

  1. Stress Responses in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Frees, Dorte; Ingmer, Hanne

    2016-01-01

    stress responses allowing it to sense and adapt to its very different niches. The stress responses often involve dramatic cellular reprogramming, and the technological advances provided by the access to whole genome sequences have let to an unprecedented insight into the global reorganization of gene...... and protein expression following stress-exposure. Characterization of global gene responses has been very helpful both in identifying regulators sensing specific environmental stress signals and overlaps between different stress responses. In this chapter we review the recent progress in our understanding...... of the specific and general S. aureusstress responses, with a special emphasis on how stress responses contribute to virulence and antibiotic resistance in this important human pathogen....

  2. Belowground neighbor perception in Arabidopsis thaliana studied by transcriptome analysis: roots of Hieracium pilosella cause biotic stress

    Directory of Open Access Journals (Sweden)

    Christoph eSchmid

    2013-08-01

    Full Text Available Root-root interactions are much more sophisticated than previously thought, yet the mechanisms of belowground neighbor perception remain largely obscure. Genome-wide transcriptome analyses allow detailed insight into plant reactions to environmental cues.A root interaction trial was set up to explore both morphological and whole genome transcriptional responses in roots of Arabidopsis thaliana in the presence or absence of an inferior competitor, Hieracium pilosella.Neighbor perception was indicated by Arabidopsis roots predominantly growing away from the neighbor (segregation, while solitary plants placed more roots towards the middle of the pot. Total biomass remained unaffected. Database comparisons in transcriptome analysis revealed considerable similarity between Arabidopsis root reactions to neighbors and reactions to pathogens. Detailed analyses of the functional category ‘biotic stress’ using MapMan tools found the sub-category ‘pathogenesis-related proteins’ highly significantly induced. A comparison to a study on intraspecific competition brought forward a core of genes consistently involved in reactions to neighbor roots.We conclude that beyond resource depletion roots perceive neighboring roots or their associated microorganisms by a relatively uniform mechanism that involves the strong induction of pathogenesis-related proteins. In an ecological context the findings reveal that belowground neighbor detection may occur independently of resource depletion, allowing for a time advantage for the root to prepare for potential interactions.

  3. Staphylococcal response to oxidative stress

    Directory of Open Access Journals (Sweden)

    Rosmarie eGaupp

    2012-03-01

    Full Text Available Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria’s interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host.

  4. Regulation of cellulose synthesis in response to stress.

    Science.gov (United States)

    Kesten, Christopher; Menna, Alexandra; Sánchez-Rodríguez, Clara

    2017-12-01

    The cell wall is a complex polysaccharide network that provides stability and protection to the plant and is one of the first layers of biotic and abiotic stimuli perception. A controlled remodeling of the primary cell wall is essential for the plant to adapt its growth to environmental stresses. Cellulose, the main component of plant cell walls is synthesized by plasma membrane-localized cellulose synthases moving along cortical microtubule tracks. Recent advancements demonstrate a tight regulation of cellulose synthesis at the primary cell wall by phytohormone networks. Stress-induced perturbations at the cell wall that modify cellulose synthesis and microtubule arrangement activate similar phytohormone-based stress response pathways. The integration of stress perception at the primary cell wall and downstream responses are likely to be tightly regulated by phytohormone signaling pathways in the context of cellulose synthesis and microtubule arrangement. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Fatty acid oxidation products ('green odour') released from perennial ryegrass following biotic and abiotic stress, potentially have antimicrobial properties against the rumen microbiota resulting in decreased biohydrogenation.

    Science.gov (United States)

    Huws, S A; Scott, M B; Tweed, J K S; Lee, M R F

    2013-11-01

    In this experiment, we investigated the effect of 'green odour' products typical of those released from fresh forage postabiotic and biotic stresses on the rumen microbiota and lipid metabolism. Hydroperoxyoctadecatrienoic acid (HP), a combination of salicylic and jasmonic acid (T), and a combination of both (HPT) were incubated in vitro in the presence of freeze-dried ground silage and rumen fluid, under rumen-like conditions. 16S rRNA (16S cDNA) HaeIII-based terminal restriction fragment length polymorphism-based (T-RFLP) dendrograms, canonical analysis of principal coordinates graphs, peak number and Shanon-Weiner diversity indices show that HP, T and HPT likely had antimicrobial effects on the microbiota compared to control incubations. Following 6 h of in vitro incubation, 15.3% of 18:3n-3 and 4.4% of 18:2n-6 was biohydrogenated in control incubations, compared with 1.3, 9.4 and 8.3% of 18:3n-3 for HP, T and HPT treatments, respectively, with negligible 18:2n-6 biohydrogenation seen. T-RFLP peaks lost due to application of HP, T and HPT likely belonged to as yet uncultured bacteria within numerous genera. Hydroperoxyoctadecatrienoic acid, T and HPT released due to plant stress potentially have an antimicrobial effect on the rumen microbiota, which may explain the decreased biohydrogenation in vitro. These data suggest that these volatile chemicals may be responsible for the higher summer n-3 content of bovine milk. © 2013 The Society for Applied Microbiology.

  6. Assessment of biotic response to heavy metal contamination in Avicennia marina mangrove ecosystems in Sydney Estuary, Australia.

    Science.gov (United States)

    Nath, Bibhash; Chaudhuri, Punarbasu; Birch, Gavin

    2014-09-01

    Mangrove forests act as a natural filter of land-derived wastewaters along industrialized tropical and sub-tropical coastlines and assist in maintaining a healthy living condition for marine ecosystems. Currently, these intertidal communities are under serious threat from heavy metal contamination induced by human activity associated with rapid urbanization and industrialization. Studies on the biotic responses of these plants to heavy metal contamination are of great significance in estuary management and maintaining coastal ecosystem health. The main objective of the present investigation was to assess the biotic response in Avicennia marina ecosystems to heavy metal contamination through the determination of metal concentrations in leaves, fine nutritive roots and underlying sediments collected in fifteen locations across Sydney Estuary (Australia). Metal concentrations (especially Cu, Pb and Zn) in the underlying sediments of A. marina were enriched to a level (based on Interim Sediment Quality Guidelines) at which adverse biological effects to flora could occasionally occur. Metals accumulated in fine nutritive roots greater than underlying sediments, however, only minor translocation of these metals to A. marina leaves was observed (mean translocation factors, TFs, for all elements micro-nutrients, Cu, Ni, Mn and Zn) were greater than non-essential elements (As, Cd, Co, Cr and Pb), suggesting that A. marina mangroves of this estuary selectively excluded non-essential elements, while regulating essential elements and limiting toxicity to plants. This study supports the notion that A. marina mangroves act as a phytostabilizer in this highly modified estuary thereby protecting the aquatic ecosystem from point or non-point sources of heavy metal contamination. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Effects of inter-varietal diversity, biotic stresses and environmental productivity on grain yield of spring barley variety mixtures

    DEFF Research Database (Denmark)

    Kiær, Lars Pødenphant; Skovgaard, Ib M.; Østergård, Hanne

    2012-01-01

    than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety...... mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity.......Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety...

  8. Evolutionary history and novel biotic interactions determine plant responses to elevated CO2 and nitrogen fertilization.

    Directory of Open Access Journals (Sweden)

    Rachel Wooliver

    Full Text Available A major frontier in global change research is predicting how multiple agents of global change will alter plant productivity, a critical component of the carbon cycle. Recent research has shown that plant responses to climate change are phylogenetically conserved such that species within some lineages are more productive than those within other lineages in changing environments. However, it remains unclear how phylogenetic patterns in plant responses to changing abiotic conditions may be altered by another agent of global change, the introduction of non-native species. Using a system of 28 native Tasmanian Eucalyptus species belonging to two subgenera, Symphyomyrtus and Eucalyptus, we hypothesized that productivity responses to abiotic agents of global change (elevated CO2 and increased soil N are unique to lineages, but that novel interactions with a non-native species mediate these responses. We tested this hypothesis by examining productivity of 1 native species monocultures and 2 mixtures of native species with an introduced hardwood plantation species, Eucalyptus nitens, to experimentally manipulated soil N and atmospheric CO2. Consistent with past research, we found that N limits productivity overall, especially in elevated CO2 conditions. However, monocultures of species within the Symphyomyrtus subgenus showed the strongest response to N (gained 127% more total biomass in elevated CO2 conditions, whereas those within the Eucalyptus subgenus did not respond to N. Root:shoot ratio (an indicator of resource use was on average greater in species pairs containing Symphyomyrtus species, suggesting that functional traits important for resource uptake are phylogenetically conserved and explaining the phylogenetic pattern in plant response to changing environmental conditions. Yet, native species mixtures with E. nitens exhibited responses to CO2 and N that differed from those of monocultures, supporting our hypothesis and highlighting that both

  9. Predicting species distribution and abundance responses to climate change: why it is essential to include biotic interactions across trophic levels.

    Science.gov (United States)

    Van der Putten, Wim H; Macel, Mirka; Visser, Marcel E

    2010-07-12

    Current predictions on species responses to climate change strongly rely on projecting altered environmental conditions on species distributions. However, it is increasingly acknowledged that climate change also influences species interactions. We review and synthesize literature information on biotic interactions and use it to argue that the abundance of species and the direction of selection during climate change vary depending on how their trophic interactions become disrupted. Plant abundance can be controlled by aboveground and belowground multitrophic level interactions with herbivores, pathogens, symbionts and their enemies. We discuss how these interactions may alter during climate change and the resulting species range shifts. We suggest conceptual analogies between species responses to climate warming and exotic species introduced in new ranges. There are also important differences: the herbivores, pathogens and mutualistic symbionts of range-expanding species and their enemies may co-migrate, and the continuous gene flow under climate warming can make adaptation in the expansion zone of range expanders different from that of cross-continental exotic species. We conclude that under climate change, results of altered species interactions may vary, ranging from species becoming rare to disproportionately abundant. Taking these possibilities into account will provide a new perspective on predicting species distribution under climate change.

  10. Plant Hormesis Management with Biostimulants of Biotic Origin in Agriculture.

    Science.gov (United States)

    Vargas-Hernandez, Marcela; Macias-Bobadilla, Israel; Guevara-Gonzalez, Ramon G; Romero-Gomez, Sergio de J; Rico-Garcia, Enrique; Ocampo-Velazquez, Rosalia V; Alvarez-Arquieta, Luz de L; Torres-Pacheco, Irineo

    2017-01-01

    Over time plants developed complex mechanisms in order to adapt themselves to the environment. Plant innate immunity is one of the most important mechanisms for the environmental adaptation. A myriad of secondary metabolites with nutraceutical features are produced by the plant immune system in order to get adaptation to new environments that provoke stress (stressors). Hormesis is a phenomenon by which a stressor (i.e., toxins, herbicides, etc.) stimulates the cellular stress response, including secondary metabolites production, in order to help organisms to establish adaptive responses. Hormetins of biotic origin (i.e., biostimulants or biological control compounds), in certain doses might enhance plant performance, however, in excessive doses they are commonly deleterious. Biostimulants or biological control compounds of biotic origin are called "elicitors" that have widely been studied as inducers of plant tolerance to biotic and abiotic stresses. The plant response toward elicitors is reminiscent of hormetic responses toward toxins in several organisms. Thus, controlled management of hormetic responses in plants using these types of compounds is expected to be an important tool to increase nutraceutical quality of plant food and trying to minimize negative effects on yields. The aim of this review is to analyze the potential for agriculture that the use of biostimulants and biological control compounds of biotic origin could have in the management of the plant hormesis. The use of homolog DNA as biostimulant or biological control compound in crop production is also discussed.

  11. On the role of salicylic acid in plant responses to environmental stresses

    DEFF Research Database (Denmark)

    Hernández, José A.; Diaz-Vivancos, Pedro; Barba Espin, Gregorio

    2017-01-01

    (NPR1), which is one of the few known redox-regulated proteins in plants. Different synthetic chemicals are able to mimic the ability of SA to activate resistance to various stresses, both biotic and abiotic, in plants with agronomic interest. Among these chemicals, 2,6-dichloroisonicotinic acid (INA......Salicylic acid (SA) is a plant hormone more commonly known by its role in human medicine than in the field of plant physiology. However, in the last two decades, SA has been described as an important signalling molecule in plants regulating growth, development and response to a wide number...... of biotic and abiotic stresses. Indeed, actually, it is well known that SA is a key signalling molecule involved in systemic acquired resistance (SAR), and recent works reported a role for SA in the response to salt or drought stresses. The precise mode of the stress hormone SA action is unclear, although...

  12. Neuronal responses to physiological stress

    DEFF Research Database (Denmark)

    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......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...

  13. Plant responses to water stress

    Science.gov (United States)

    Kar, Rup Kumar

    2011-01-01

    Terrestrial plants most often encounter drought stress because of erratic rainfall which has become compounded due to present climatic changes.Responses of plants to water stress may be assigned as either injurious change or tolerance index. One of the primary and cardinal changes in response to drought stress is the generation of reactive oxygen species (ROS), which is being considered as the cause of cellular damage. However, recently a signaling role of such ROS in triggering the ROS scavenging system that may confer protection or tolerance against stress is emerging. Such scavenging system consists of antioxidant enzymes like SOD, catalase and peroxidases, and antioxidant compounds like ascorbate, reduced glutathione; a balance between ROS generation and scavenging ultimately determines the oxidative load. As revealed in case of defence against pathogen, signaling via ROS is initiated by NADPH oxidase-catalyzed superoxide generation in the apoplastic space (cell wall) followed by conversion to hydrogen peroxide by the activity of cell wall-localized SOD. Wall peroxidase may also play role in ROS generation for signaling. Hydrogen peroxide may use Ca2+ and MAPK pathway as downstream signaling cascade. Plant hormones associated with stress responses like ABA and ethylene play their role possibly via a cross talk with ROS towards stress tolerance, thus projecting a dual role of ROS under drought stress. PMID:22057331

  14. Individual heat stress response

    NARCIS (Netherlands)

    Havenith, G.

    1997-01-01

    In 5 experiments, heterogeneous subject groups (large variations in _VO2 max, regular daily activity level, mass, body surface area (AD), % body fat, and AD/mass ratio) were tested for their physiological response while exercising on a cycle ergometer at a relative (45% _VO2 max; REL) or an absolute

  15. A WRKY transcription factor from Withania somnifera regulates triterpenoid withanolide accumulation and biotic stress tolerance through modulation of phytosterol and defense pathways.

    Science.gov (United States)

    Singh, Anup Kumar; Kumar, Sarma Rajeev; Dwivedi, Varun; Rai, Avanish; Pal, Shaifali; Shasany, Ajit K; Nagegowda, Dinesh A

    2017-08-01

    Withania somnifera produces pharmacologically important triterpenoid withanolides that are derived via phytosterol pathway; however, their biosynthesis and regulation remain to be elucidated. A jasmonate- and salicin-inducible WRKY transcription factor from W. somnifera (WsWRKY1) exhibiting correlation with withaferin A accumulation was functionally characterized employing virus-induced gene silencing and overexpression studies combined with transcript and metabolite analyses, and chromatin immunoprecipitation assay. WsWRKY1 silencing resulted in stunted plant growth, reduced transcripts of phytosterol pathway genes with corresponding reduction in phytosterols and withanolides in W. somnifera. Its overexpression elevated the biosynthesis of triterpenoids in W. somnifera (phytosterols and withanolides), as well as tobacco and tomato (phytosterols). Moreover, WsWRKY1 binds to W-box sequences in promoters of W. somnifera genes encoding squalene synthase and squalene epoxidase, indicating its direct regulation of triterpenoid pathway. Furthermore, while WsWRKY1 silencing in W. somnifera compromised the tolerance to bacterial growth, fungal infection, and insect feeding, its overexpression in tobacco led to improved biotic stress tolerance. Together these findings demonstrate that WsWRKY1 has a positive regulatory role on phytosterol and withanolides biosynthesis, and defense against biotic stress, highlighting its importance as a metabolic engineering tool for simultaneous improvement of triterpenoid biosynthesis and plant defense. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  16. Biotic Responses of Headwater Streams to Geophysical Alteration and Disturbance Related to Climate Change

    Science.gov (United States)

    Gresswell, R. E.; Sedell, E. R.; Cannon, S.; Hostetler, S. W.; Williams, J. E.; Haak, A. L.; Kershner, J. L.

    2009-12-01

    Climate change will potentially alter physical habitat availability for trout species (both native and nonnative) in the western USA, and ultimately affect population distribution and abundance in watersheds across the region. To understand the biological consequences of habitat alteration associated with climate change, we have developed models linking contemporary patterns of occurrence and abundance to geomorphic variables (e.g., aspect, elevation, and slope) and stream conditions derived from the habitat (e.g., temperature, discharge, and flood regimes). Because headwater streams may be especially susceptible to catastrophic disturbances in the form of debris flow torrents that have the potential to radically alter the physical structure of channels and sometimes extirpate local fish populations, we are focusing fine-scale spatial analyses in the high elevation systems. Risks of such disturbances increase exponentially in landscapes that have experienced recent wildfires when high-intensity precipitation or runoff events occur. Although predicting the timing, extent, and severity of future wildfires or subsequent precipitation and runoff events is difficult, it is possible to identify channels within stream networks that may be prone to debris flows. These channels can be identified using models based on characteristic storm and burn scenarios and geographic information describing topographic, soil, and vegetation characteristics. At-risk channels are being mapped throughout the stream networks within the study areas in the headwaters of the Colorado River to provide information about the potential for catastrophic population disturbance in response to variety of wildfire and post-wildfire storm scenarios.

  17. Abiotic stressors and stress responses

    DEFF Research Database (Denmark)

    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...... life history traits of stressed organisms, and ii) to what extent trait responses influence individual and population responses. Common response mechanisms are evident at molecular and cellular scales but become rather difficult to define at higher levels due to evolutionary distance and environmental...

  18. Plant growth regulators ameliorate or exacerbate abiotic and biotic stress effects on Zea mays kernel weight in a genotype-specific manner

    OpenAIRE

    Wang, Yishi; Stutts, Lauren; Stapleton, Ann

    2016-01-01

    Plant growth regulators have documented roles in plant responses to single stresses. In combined-stress environments, plants display novel genetic architecture for growth traits and the response to growth regulators is unclear. We investigated the role of plant growth regulators in combined-stress responses in Zea mays. Twelve maize inbreds were exposed to all combinations of the following stressors: drought, nitrogen, and density stress. Chemical treatments were utilized to alter balances of...

  19. Carbonate-platform response to the Toarcian Oceanic Anoxic Event in the southern hemisphere: Implications for climatic change and biotic platform demise

    Science.gov (United States)

    Han, Zhong; Hu, Xiumian; Kemp, David B.; Li, Juan

    2018-05-01

    The Toarcian Oceanic Anoxic Event (T-OAE, ∼183 Ma) was a profound short-term environmental perturbation associated with the large-scale release of 13C-depleted carbon into the global ocean-atmosphere system, which resulted in a significant negative carbon-isotope excursion (CIE). The general lack of characteristic T-OAE records outside of the northern hemisphere means that the precise environmental effects and significance of this event are uncertain. Many biotic carbonate platforms of the northern hemisphere western Tethys drowned or shifted to non-skeletal platforms during the early Toarcian. However, southern hemisphere records of Toarcian carbonate platforms are rare, and thus the extent and significance of biotic platform demise during the T-OAE is unclear. Here we present high-resolution geochemical and sedimentological data across two Pliensbachian-Toarcian shallow-water carbonate-platform sections exposed in the Tibetan Himalaya. These sections were located paleogeographically on the open southeastern tropical Tethyan margin in the southern hemisphere. The T-OAE in the Tibetan Himalaya is marked by a negative CIE in organic matter. Our sedimentological analysis of the two sections reveals an abundance of storm deposits within the T-OAE interval, which emphasizes a close link between warming and tropical storms during the T-OAE event, in line with evidence recently provided from western Tethyan sections of the northern hemisphere. In addition, our analysis also reveals extensive biotic carbonate-platform demise by drowning or changing to non-skeletal carbonates coincident with the onset of the CIE. Taken together, our results suggest that rapid and pervasive seawater warming in response to carbon release likely played a significant role in sudden biotic carbonate platform demise, and suppression/postponement of biotic platform re-development along the whole tropical/subtropical Tethyan margin.

  20. Pathogen-induced Caenorhabditis elegans developmental plasticity has a hormetic effect on the resistance to biotic and abiotic stresses

    Directory of Open Access Journals (Sweden)

    Leroy Magali

    2012-09-01

    Full Text Available Abstract Background Phenotypic plasticity, i.e. the capacity to change the phenotype in response to changes in the environment without alteration of the genotype, is important for coping with unstable environments. In spite of the ample evidence that microorganisms are a major environmental component playing a significant role in eukaryotic organisms health and disease, there is not much information about the effect of microorganism-induced developmental phenotypic plasticity on adult animals’ stress resistance and longevity. Results We examined the consequences of development of Caenorhabditis elegans larvae fed with different bacterial strains on stress resistance and lifespan of adult nematodes. Bacterial strains used in this study were either pathogenic or innocuous to nematodes. Exposure to the pathogen during development did not affect larval survival. However, the development of nematodes on the pathogenic bacterial strains increased lifespan of adult nematodes exposed to the same or a different pathogen. A longer nematode lifespan, developed on pathogens and exposed to pathogens as adults, did not result from an enhanced capacity to kill bacteria, but is likely due to an increased tolerance to the damage inflicted by the pathogenic bacteria. We observed that adult nematodes developed on a pathogen induce higher level of expression of the hsp-16.2 gene and have higher resistance to heat shock than nematodes developed on an innocuous strain. Therefore, the increased resistance to pathogens could be, at least partially, due to the early induction of the heat shock response in nematodes developed on pathogens. The lifespan increase is controlled by the DBL-1 transforming growth factor beta-like, DAF-2/DAF-16 insulin-like, and p38 MAP kinase pathways. Therefore, the observed modulation of adult nematode lifespans by developmental exposure to a pathogen is likely a genetically controlled response. Conclusions Our study shows that development

  1. Plant Responses to Nanoparticle Stress

    Directory of Open Access Journals (Sweden)

    Zahed Hossain

    2015-11-01

    Full Text Available With the rapid advancement in nanotechnology, release of nanoscale materials into the environment is inevitable. Such contamination may negatively influence the functioning of the ecosystems. Many manufactured nanoparticles (NPs contain heavy metals, which can cause soil and water contamination. Proteomic techniques have contributed substantially in understanding the molecular mechanisms of plant responses against various stresses by providing a link between gene expression and cell metabolism. As the coding regions of genome are responsible for plant adaptation to adverse conditions, protein signatures provide insights into the phytotoxicity of NPs at proteome level. This review summarizes the recent contributions of plant proteomic research to elaborate the complex molecular pathways of plant response to NPs stress.

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

    OpenAIRE

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

    2010-01-01

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

  3. Understanding the Posttranscriptional Regulation of Plant Responses to Abiotic Stress

    KAUST Repository

    AlShareef, Sahar A.

    2017-06-01

    Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and biotic and abiotic stresses. Recent work showed that AS is pervasive across plant species, with more than 60% of intron-containing genes producing different isoforms. Mammalian cell-based assays have discovered various AS small-molecule inhibitors that perturb splicing and thereby provide invaluable tools for use as chemical probes to uncover the molecular underpinnings of splicing regulation and as potential anticancer compounds. Here, I show that the macrolide Pladienolide B (PB) and herboxidiene (GEX1A) inhibits both constitutive and alternative splicing, mimics an abiotic stress signal, and activates the abscisic acid (ABA) pathway in plants. Moreover, PB and GEX1A activate genome-wide transcriptional patterns involved in abiotic stress responses in plants. PB and GEX1A treatment triggered the ABA signaling pathway, activated ABA-inducible promoters, and led to stomatal closure. Interestingly, PB and GEX1A elicited similar cellular changes, including alterations in the patterns of transcription and splicing, suggesting that these compounds might target the same spliceosome complex in plant cells. This work establishes PB and GEX1A as potent splicing inhibitors in plants that can be used to probe the assembly, dynamics, and molecular functions of the spliceosome and to study the interplay between splicing stress and abiotic stresses, as well as having potential biotechnological applications.

  4. "Omics" of maize stress response for sustainable food production: opportunities and challenges.

    Science.gov (United States)

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

    2014-12-01

    Maize originated in the highlands of Mexico approximately 8700 years ago and is one of the most commonly grown cereal crops worldwide, followed by wheat and rice. Abiotic stresses (primarily drought, salinity, and high and low temperatures), together with biotic stresses (primarily fungi, viruses, and pests), negatively affect maize growth, development, and eventually production. To understand the response of maize to abiotic and biotic stresses and its mechanism of stress tolerance, high-throughput omics approaches have been used in maize stress studies. Integrated omics approaches are crucial for dissecting the temporal and spatial system-level changes that occur in maize under various stresses. In this comprehensive analysis, we review the primary types of stresses that threaten sustainable maize production; underscore the recent advances in maize stress omics, especially proteomics; and discuss the opportunities, challenges, and future directions of maize stress omics, with a view to sustainable food production. The knowledge gained from studying maize stress omics is instrumental for improving maize to cope with various stresses and to meet the food demands of the exponentially growing global population. Omics systems science offers actionable potential solutions for sustainable food production, and we present maize as a notable case study.

  5. Genome-wide identification of WRKY family genes and their response to cold stress in Vitis vinifera

    Science.gov (United States)

    WRKY transcription factors are one of the largest families of transcriptional regulators in plants. WRKY genes are not only found to play significant roles in biotic and abiotic stress response, but also regulate growth and development. Grapevine (Vitis vinifera) production is largely limited by str...

  6. The Critical Role of Potassium in Plant Stress Response

    Directory of Open Access Journals (Sweden)

    Min Wang

    2013-04-01

    Full Text Available Agricultural production continues to be constrained by a number of biotic and abiotic factors that can reduce crop yield quantity and quality. Potassium (K is an essential nutrient that affects most of the biochemical and physiological processes that influence plant growth and metabolism. It also contributes to the survival of plants exposed to various biotic and abiotic stresses. The following review focuses on the emerging role of K in defending against a number of biotic and abiotic stresses, including diseases, pests, drought, salinity, cold and frost and waterlogging. The availability of K and its effects on plant growth, anatomy, morphology and plant metabolism are discussed. The physiological and molecular mechanisms of K function in plant stress resistance are reviewed. This article also evaluates the potential for improving plant stress resistance by modifying K fertilizer inputs and highlights the future needs for research about the role of K in agriculture.

  7. STRESS RESPONSE STUDIES USING ANIMAL MODELS

    Science.gov (United States)

    This presentation will provide the evidence that ozone exposure in animal models induce neuroendocrine stress response and this stress response modulates lung injury and inflammation through adrenergic and glucocorticoid receptors.

  8. Calcium Signalling in Plant Biotic Interactions

    Directory of Open Access Journals (Sweden)

    Didier Aldon

    2018-02-01

    Full Text Available Calcium (Ca2+ is a universal second messenger involved in various cellular processes, leading to plant development and to biotic and abiotic stress responses. Intracellular variation in free Ca2+ concentration is among the earliest events following the plant perception of environmental change. These Ca2+ variations differ in their spatio-temporal properties according to the nature, strength and duration of the stimulus. However, their conversion into biological responses requires Ca2+ sensors for decoding and relaying. The occurrence in plants of calmodulin (CaM but also of other sets of plant-specific Ca2+ sensors such as calmodulin-like proteins (CMLs, Ca2+-dependent protein kinases (CDPKs and calcineurin B-like proteins (CBLs indicate that plants possess specific tools and machineries to convert Ca2+ signals into appropriate responses. Here, we focus on recent progress made in monitoring the generation of Ca2+ signals at the whole plant or cell level and their long distance propagation during biotic interactions. The contribution of CaM/CMLs and CDPKs in plant immune responses mounted against bacteria, fungi, viruses and insects are also presented.

  9. Structure, function and networks of transcription factors involved in abiotic stress responses

    DEFF Research Database (Denmark)

    Lindemose, Søren; O'Shea, Charlotte; Jensen, Michael Krogh

    2013-01-01

    Transcription factors (TFs) are master regulators of abiotic stress responses in plants. This review focuses on TFs from seven major TF families, known to play functional roles in response to abiotic stresses, including drought, high salinity, high osmolarity, temperature extremes...... and the phytohormone ABA. Although ectopic expression of several TFs has improved abiotic stress tolerance in plants, fine-tuning of TF expression and protein levels remains a challenge to avoid crop yield loss. To further our understanding of TFs in abiotic stress responses, emerging gene regulatory networks based...... on TFs and their direct targets genes are presented. These revealed components shared between ABA-dependent and independent signaling as well as abiotic and biotic stress signaling. Protein structure analysis suggested that TFs hubs of large interactomes have extended regions with protein intrinsic...

  10. Evolution and Stress Responses of Gossypium hirsutum SWEET Genes.

    Science.gov (United States)

    Li, Wei; Ren, Zhongying; Wang, Zhenyu; Sun, Kuan; Pei, Xiaoyu; Liu, Yangai; He, Kunlun; Zhang, Fei; Song, Chengxiang; Zhou, Xiaojian; Zhang, Wensheng; Ma, Xiongfeng; Yang, Daigang

    2018-03-08

    The SWEET (sugars will eventually be exported transporters) proteins are sugar efflux transporters containing the MtN3_saliva domain, which affects plant development as well as responses to biotic and abiotic stresses. These proteins have not been functionally characterized in the tetraploid cotton, Gossypium hirsutum , which is a widely cultivated cotton species. In this study, we comprehensively analyzed the cotton SWEET gene family. A total of 55 putative G. hirsutum SWEET genes were identified. The GhSWEET genes were classified into four clades based on a phylogenetic analysis and on the examination of gene structural features. Moreover, chromosomal localization and an analysis of homologous genes in Gossypium arboreum , Gossypium raimondii , and G. hirsutum suggested that a whole-genome duplication, several tandem duplications, and a polyploidy event contributed to the expansion of the cotton SWEET gene family, especially in Clade III and IV. Analyses of cis -acting regulatory elements in the promoter regions, expression profiles, and artificial selection revealed that the GhSWEET genes were likely involved in cotton developmental processes and responses to diverse stresses. These findings may clarify the evolution of G. hirsutum SWEET gene family and may provide a foundation for future functional studies of SWEET proteins regarding cotton development and responses to abiotic stresses.

  11. WRKY proteins: signaling and regulation of expression during abiotic stress responses.

    Science.gov (United States)

    Banerjee, Aditya; Roychoudhury, Aryadeep

    2015-01-01

    WRKY proteins are emerging players in plant signaling and have been thoroughly reported to play important roles in plants under biotic stress like pathogen attack. However, recent advances in this field do reveal the enormous significance of these proteins in eliciting responses induced by abiotic stresses. WRKY proteins act as major transcription factors, either as positive or negative regulators. Specific WRKY factors which help in the expression of a cluster of stress-responsive genes are being targeted and genetically modified to induce improved abiotic stress tolerance in plants. The knowledge regarding the signaling cascade leading to the activation of the WRKY proteins, their interaction with other proteins of the signaling pathway, and the downstream genes activated by them are altogether vital for justified targeting of the WRKY genes. WRKY proteins have also been considered to generate tolerance against multiple abiotic stresses with possible roles in mediating a cross talk between abiotic and biotic stress responses. In this review, we have reckoned the diverse signaling pattern and biological functions of WRKY proteins throughout the plant kingdom along with the growing prospects in this field of research.

  12. Longevity and the stress response in Drosophila

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Loeschcke, Volker

    2007-01-01

    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...... research. Keywords: Ageing; Stress response; Hsp; Drosophila; Stress......The concept that lifespan is a function of the capacity to withstand extrinsic stress is very old. In concordance with this, long-lived individuals often have increased resistance against a variety of stresses throughout life. Genes underlying the stress response may therefore have the ability...

  13. Relationship of Melatonin and Salicylic Acid in Biotic/Abiotic Plant Stress Responses

    OpenAIRE

    Josefa Hernández-Ruiz; Marino B. Arnao

    2018-01-01

    Melatonin (N-acetyl-5-methoxytryptamine) was discovered in plants in 1995, while salicylic acid was the name given to the active ingredient of willow in 1838. From a physiological point of view, these two molecules present in plants have never been compared, even though they have a great number of similarities, as we shall see in this work. Both molecules have biosynthesis pathways that share a common precursor and both play a relevant role in the physiology of plants, especially in aspects r...

  14. The Importance of Biotic vs. Abiotic Drivers of Local Plant Community Composition Along Regional Bioclimatic Gradients.

    Directory of Open Access Journals (Sweden)

    Kari Klanderud

    Full Text Available We assessed if the relative importance of biotic and abiotic factors for plant community composition differs along environmental gradients and between functional groups, and asked which implications this may have in a warmer and wetter future. The study location is a unique grid of sites spanning regional-scale temperature and precipitation gradients in boreal and alpine grasslands in southern Norway. Within each site we sampled vegetation and associated biotic and abiotic factors, and combined broad- and fine-scale ordination analyses to assess the relative explanatory power of these factors for species composition. Although the community responses to biotic and abiotic factors did not consistently change as predicted along the bioclimatic gradients, abiotic variables tended to explain a larger proportion of the variation in species composition towards colder sites, whereas biotic variables explained more towards warmer sites, supporting the stress gradient hypothesis. Significant interactions with precipitation suggest that biotic variables explained more towards wetter climates in the sub alpine and boreal sites, but more towards drier climates in the colder alpine. Thus, we predict that biotic interactions may become more important in alpine and boreal grasslands in a warmer future, although more winter precipitation may counteract this trend in oceanic alpine climates. Our results show that both local and regional scales analyses are needed to disentangle the local vegetation-environment relationships and their regional-scale drivers, and biotic interactions and precipitation must be included when predicting future species assemblages.

  15. Differences in Competitive Ability between Plants from Nonnative and Native Populations of a Tropical Invader Relates to Adaptive Responses in Abiotic and Biotic Environments

    Science.gov (United States)

    Liao, Zhi-Yong; Zhang, Ru; Barclay, Gregor F.; Feng, Yu-Long

    2013-01-01

    The evolution of competitive ability of invasive plant species is generally studied in the context of adaptive responses to novel biotic environments (enemy release) in introduced ranges. However, invasive plants may also respond to novel abiotic environments. Here we studied differences in competitive ability between Chromolaena odorata plants of populations from nonnative versus native ranges, considering biogeographical differences in both biotic and abiotic environments. An intraspecific competition experiment was conducted at two nutrient levels in a common garden. In both low and high nutrient treatments, C. odorata plants from nonnative ranges showed consistently lower root to shoot ratios than did plants from native ranges grown in both monoculture and competition. In the low nutrient treatment, C. odorata plants from nonnative ranges showed significantly lower competitive ability (competition-driven decreases in plant height and biomass were more), which was associated with their lower root to shoot ratios and higher total leaf phenolic content (defense trait). In the high nutrient treatment, C. odorata plants from nonnative ranges showed lower leaf toughness and cellulosic contents (defense traits) but similar competitive ability compared with plants from native ranges, which was also associated with their lower root to shoot ratios. Our results indicate that genetically based shifts in biomass allocation (responses to abiotic environments) also influence competitive abilities of invasive plants, and provide a first potential mechanism for the interaction between range and environment (environment-dependent difference between ranges). PMID:23977140

  16. Generating markers based on biotic stress of protein system in and tandem repeats sequence for Aquilaria sp

    International Nuclear Information System (INIS)

    Azhar Mohamad; Muhammad Hanif Azhari N; Siti Norhayati Ismail

    2014-01-01

    Aquilaria sp. belongs to the Thymelaeaceae family and is well distributed in Asia region. The species has multipurpose use from root to shoot and is an economically important crop, which generates wide interest in understanding genetic diversity of the species. Knowledge on DNA-based markers has become a prerequisite for more effective application of molecular marker techniques in breeding and mapping programs. In this work, both targeted genes and tandem repeat sequences were used for DNA fingerprinting in Aquilaria sp. A total of 100 ISSR (inter simple sequence repeat) primers and 50 combination pairs of specific primers derived from conserved region of a specific protein known as system in were optimized. 38 ISSR primers were found affirmative for polymorphism evaluation study and were generated from both specific and degenerate ISSR primers. And one utmost combination of system in primers showed significant results in distinguishing the Aquilaria sp. In conclusion, polymorphism derived from ISSR profiling and targeted stress genes of protein system in proved as a powerful approach for identification and molecular classification of Aquilaria sp. which will be useful for diversification in identifying any mutant lines derived from nature. (author)

  17. Agreeableness, Extraversion, Stressor and Physiological Stress Response

    OpenAIRE

    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...

  18. Bell pepper rootstock response to Phytophthora capsici under salinity stress

    Science.gov (United States)

    Vegetable grafting is currently used as an eco-friendly technology to increase crop productivity and overcome several biotic and abiotic stress conditions that affect Cucurbitaceae and Solanaceae vegetable crops. In recent years, researchers with breeding programs and seed companies have selected ro...

  19. Global Analysis of WRKY Genes and Their Response to Dehydration and Salt Stress in Soybean.

    Science.gov (United States)

    Song, Hui; Wang, Pengfei; Hou, Lei; Zhao, Shuzhen; Zhao, Chuanzhi; Xia, Han; Li, Pengcheng; Zhang, Ye; Bian, Xiaotong; Wang, Xingjun

    2016-01-01

    WRKY proteins are plant specific transcription factors involved in various developmental and physiological processes, especially in biotic and abiotic stress resistance. Although previous studies suggested that WRKY proteins in soybean (Glycine max var. Williams 82) involved in both abiotic and biotic stress responses, the global information of WRKY proteins in the latest version of soybean genome (Wm82.a2v1) and their response to dehydration and salt stress have not been reported. In this study, we identified 176 GmWRKY proteins from soybean Wm82.a2v1 genome. These proteins could be classified into three groups, namely group I (32 proteins), group II (120 proteins), and group III (24 proteins). Our results showed that most GmWRKY genes were located on Chromosome 6, while chromosome 11, 12, and 20 contained the least number of this gene family. More GmWRKY genes were distributed on the ends of chromosomes to compare with other regions. The cis-acting elements analysis suggested that GmWRKY genes were transcriptionally regulated upon dehydration and salt stress. RNA-seq data analysis indicated that three GmWRKY genes responded negatively to dehydration, and 12 genes positively responded to salt stress at 1, 6, and 12 h, respectively. We confirmed by qRT-PCR that the expression of GmWRKY47 and GmWRKY 58 genes was decreased upon dehydration, and the expression of GmWRKY92, 144 and 165 genes was increased under salt treatment.

  20. Tonic immobility differentiates stress responses in PTSD

    NARCIS (Netherlands)

    Fragkaki, I; Stins, J.F.; Roelofs, K.; Jongedijk, R.A.; Hagenaars, M.A.

    2016-01-01

    Background: Tonic immobility (TI) is a state of physical immobility associated with extreme stress and the development of posttraumatic stress disorder (PTSD). However, it is unknown whether TI is associated with a distinct actual stress response, i.e., objective immobility measured by a

  1. Plant natriuretic peptides are apoplastic and paracrine stress response molecules

    KAUST Repository

    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.

  2. Virus-induced gene silencing of Withania somnifera squalene synthase negatively regulates sterol and defence-related genes resulting in reduced withanolides and biotic stress tolerance.

    Science.gov (United States)

    Singh, Anup Kumar; Dwivedi, Varun; Rai, Avanish; Pal, Shaifali; Reddy, Sajjalavarahalli Gangireddy Eswara; Rao, Dodaghatta Krishnarao Venkata; Shasany, Ajit Kumar; Nagegowda, Dinesh A

    2015-12-01

    Withania somnifera (L.) Dunal is an important Indian medicinal plant that produces withanolides, which are triterpenoid steroidal lactones having diverse biological activities. To enable fast and efficient functional characterization of genes in this slow-growing and difficult-to-transform plant, a virus-induced gene silencing (VIGS) was established by silencing phytoene desaturase (PDS) and squalene synthase (SQS). VIGS of the gene encoding SQS, which provides precursors for triterpenoids, resulted in significant reduction of squalene and withanolides, demonstrating its application in studying withanolides biosynthesis in W. somnifera leaves. A comprehensive analysis of gene expression and sterol pathway intermediates in WsSQS-vigs plants revealed transcriptional modulation with positive feedback regulation of mevalonate pathway genes, and negative feed-forward regulation of downstream sterol pathway genes including DWF1 (delta-24-sterol reductase) and CYP710A1 (C-22-sterol desaturase), resulting in significant reduction of sitosterol, campesterol and stigmasterol. However, there was little effect of SQS silencing on cholesterol, indicating the contribution of sitosterol, campesterol and stigmasterol, but not of cholesterol, towards withanolides formation. Branch-point oxidosqualene synthases in WsSQS-vigs plants exhibited differential regulation with reduced CAS (cycloartenol synthase) and cycloartenol, and induced BAS (β-amyrin synthase) and β-amyrin. Moreover, SQS silencing also led to the down-regulation of brassinosteroid-6-oxidase-2 (BR6OX2), pathogenesis-related (PR) and nonexpressor of PR (NPR) genes, resulting in reduced tolerance to bacterial and fungal infection as well as to insect feeding. Taken together, SQS silencing negatively regulated sterol and defence-related genes leading to reduced phytosterols, withanolides and biotic stress tolerance, thus implicating the application of VIGS for functional analysis of genes related to withanolides

  3. Identification and characterization of wheat long non-protein coding RNAs responsive to powdery mildew infection and heat stress by using microarray analysis and SBS sequencing

    Directory of Open Access Journals (Sweden)

    Peng Huiru

    2011-04-01

    Full Text Available Abstract Background Biotic and abiotic stresses, such as powdery mildew infection and high temperature, are important limiting factors for yield and grain quality in wheat production. Emerging evidences suggest that long non-protein coding RNAs (npcRNAs are developmentally regulated and play roles in development and stress responses of plants. However, identification of long npcRNAs is limited to a few plant species, such as Arabidopsis, rice and maize, no systematic identification of long npcRNAs and their responses to abiotic and biotic stresses is reported in wheat. Results In this study, by using computational analysis and experimental approach we identified 125 putative wheat stress responsive long npcRNAs, which are not conserved among plant species. Among them, some were precursors of small RNAs such as microRNAs and siRNAs, two long npcRNAs were identified as signal recognition particle (SRP 7S RNA variants, and three were characterized as U3 snoRNAs. We found that wheat long npcRNAs showed tissue dependent expression patterns and were responsive to powdery mildew infection and heat stress. Conclusion Our results indicated that diverse sets of wheat long npcRNAs were responsive to powdery mildew infection and heat stress, and could function in wheat responses to both biotic and abiotic stresses, which provided a starting point to understand their functions and regulatory mechanisms in the future.

  4. General Stress Responses in the Honey Bee

    Directory of Open Access Journals (Sweden)

    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.

  5. Expression of the 1-SST and 1-FFT genes and consequent fructan accumulation in Agave tequilana and A. inaequidens is differentially induced by diverse (a)biotic-stress related elicitors.

    Science.gov (United States)

    Suárez-González, Edgar Martín; López, Mercedes G; Délano-Frier, John P; Gómez-Leyva, Juan Florencio

    2014-02-15

    The expression of genes coding for sucrose:sucrose 1-fructosyltransferase (1-SST; EC 2.4.1.99) and fructan:fructan 1-fructosyltransferase (1-FFT; EC 2.4.1.100), both fructan biosynthesizing enzymes, characterization by TLC and HPAEC-PAD, as well as the quantification of the fructo-oligosaccharides (FOS) accumulating in response to the exogenous application of sucrose, kinetin (cytokinin) or other plant hormones associated with (a)biotic stress responses were determined in two Agave species grown in vitro, domesticated Agave tequilana var. azul and wild A. inaequidens. It was found that elicitors such as salicylic acid (SA), and jasmonic acid methyl ester (MeJA) had the strongest effect on fructo-oligosaccharide (FOS) accumulation. The exogenous application of 1mM SA induced a 36-fold accumulation of FOS of various degrees of polymerization (DP) in stems of A. tequilana. Other treatments, such as 50mM abscisic acid (ABA), 8% Sucrose (Suc), and 1.0 mg L(-1) kinetin (KIN) also led to a significant accumulation of low and high DP FOS in this species. Conversely, treatment with 200 μM MeJA, which was toxic to A. tequilana, induced an 85-fold accumulation of FOS in the stems of A. inaequidens. Significant FOS accumulation in this species also occurred in response to treatments with 1mM SA, 8% Suc, and 10% polyethylene glycol (PEG). Maximum yields of 13.6 and 8.9 mg FOS per g FW were obtained in stems of A. tequilana and A. inaequidens, respectively. FOS accumulation in the above treatments was tightly associated with increased expression levels of either the 1-FFT or the 1-SST gene in tissues of both Agave species. Copyright © 2013 Elsevier GmbH. All rights reserved.

  6. Alternative Splicing Control of Abiotic Stress Responses.

    Science.gov (United States)

    Laloum, Tom; Martín, Guiomar; Duque, Paula

    2018-02-01

    Alternative splicing, which generates multiple transcripts from the same gene, is an important modulator of gene expression that can increase proteome diversity and regulate mRNA levels. In plants, this post-transcriptional mechanism is markedly induced in response to environmental stress, and recent studies have identified alternative splicing events that allow rapid adjustment of the abundance and function of key stress-response components. In agreement, plant mutants defective in splicing factors are severely impaired in their response to abiotic stress. Notably, mounting evidence indicates that alternative splicing regulates stress responses largely by targeting the abscisic acid (ABA) pathway. We review here current understanding of post-transcriptional control of plant stress tolerance via alternative splicing and discuss research challenges for the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. The Multiple Functions of the Nucleolus in Plant Development, Disease and Stress Responses

    Directory of Open Access Journals (Sweden)

    Natalia O. Kalinina

    2018-02-01

    Full Text Available The nucleolus is the most conspicuous domain in the eukaryotic cell nucleus, whose main function is ribosomal RNA (rRNA synthesis and ribosome biogenesis. However, there is growing evidence that the nucleolus is also implicated in many other aspects of cell biology, such as regulation of cell cycle, growth and development, senescence, telomerase activity, gene silencing, responses to biotic and abiotic stresses. In the first part of the review, we briefly assess the traditional roles of the plant nucleolus in rRNA synthesis and ribosome biogenesis as well as possible functions in other RNA regulatory pathways such as splicing, nonsense-mediated mRNA decay and RNA silencing. In the second part of the review we summarize recent progress and discuss already known and new hypothetical roles of the nucleolus in plant growth and development. In addition, this part will highlight studies showing new nucleolar functions involved in responses to pathogen attack and abiotic stress. Cross-talk between the nucleolus and Cajal bodies is also discussed in the context of their association with poly(ADP ribosepolymerase (PARP, which is known to play a crucial role in various physiological processes including growth, development and responses to biotic and abiotic stresses.

  8. The Multiple Functions of the Nucleolus in Plant Development, Disease and Stress Responses

    Science.gov (United States)

    Kalinina, Natalia O.; Makarova, Svetlana; Makhotenko, Antonida; Love, Andrew J.; Taliansky, Michael

    2018-01-01

    The nucleolus is the most conspicuous domain in the eukaryotic cell nucleus, whose main function is ribosomal RNA (rRNA) synthesis and ribosome biogenesis. However, there is growing evidence that the nucleolus is also implicated in many other aspects of cell biology, such as regulation of cell cycle, growth and development, senescence, telomerase activity, gene silencing, responses to biotic and abiotic stresses. In the first part of the review, we briefly assess the traditional roles of the plant nucleolus in rRNA synthesis and ribosome biogenesis as well as possible functions in other RNA regulatory pathways such as splicing, nonsense-mediated mRNA decay and RNA silencing. In the second part of the review we summarize recent progress and discuss already known and new hypothetical roles of the nucleolus in plant growth and development. In addition, this part will highlight studies showing new nucleolar functions involved in responses to pathogen attack and abiotic stress. Cross-talk between the nucleolus and Cajal bodies is also discussed in the context of their association with poly(ADP ribose)polymerase (PARP), which is known to play a crucial role in various physiological processes including growth, development and responses to biotic and abiotic stresses. PMID:29479362

  9. ABA and GA3 regulate the synthesis of primary and secondary metabolites related to alleviation from biotic and abiotic stresses in grapevine.

    Science.gov (United States)

    Murcia, Germán; Fontana, Ariel; Pontin, Mariela; Baraldi, Rita; Bertazza, Gianpaolo; Piccoli, Patricia N

    2017-03-01

    3 applications to grapevine plants cv. Malbec influenced the synthesis of primary and secondary metabolites known to be essential for coping with biotic and abiotic stresses. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Identification of drought, cadmium and root-lesion nematode infection stress-responsive transcription factors in ramie

    Directory of Open Access Journals (Sweden)

    Zheng Xia

    2016-01-01

    Full Text Available Drought, cadmium (Cd stress, and root lesion nematode (RLN infection are three of the most important stresses affecting ramie growth and development; therefore, ramie breeding programs focus on their management more than on any other abiotic or biotic stresses. The fact that only a small number of stress-responsive transcription factors (TFs have been identified so far is a major obstacle in the elucidation of mechanisms regulating the response to these three stresses in ramie. In this study, in order to uncover more stress-responsive TFs, a total of 179 nonredundant genes with full-length open reading frames from the MYB, AP2/ERF, bZIP, HD-ZIP, and COL families were obtained by searching for against the ramie transcriptome. Expression pattern analysis demonstrated that most of these genes showed relatively higher expression in the stem xylem and bast than in other tissues. Among these genes, 96 genes were found to be involved in responses to drought, Cd exposure, or RLN-infection. The expression of 54 of these genes was regulated by at least two stresses. These stress-responsive TFs probably have roles in the regulation of stress tolerance. The discovery of these stress-responsive TFs will be helpful for furthering our understanding of the mechanisms that regulate stress responses in ramie.

  11. The endoplasmic reticulum stress response in disease ...

    African Journals Online (AJOL)

    Rafael Vincent M. Manalo

    2017-07-12

    Jul 12, 2017 ... Review. The endoplasmic reticulum stress response in disease pathogenesis and pathophysiology .... This is an open access article under the CC BY-NC-ND license ... chain binding protein (BIP); however, ER stress permits the release, .... drugs designed to alleviate it often cause more harm long-term.

  12. ROS signaling and stomatal movement in plant responses to drought stress and pathogen attack.

    Science.gov (United States)

    Qi, Junsheng; Song, Chun-Peng; Wang, Baoshan; Zhou, Jianmin; Kangasjärvi, Jaakko; Zhu, Jian-Kang; Gong, Zhizhong

    2018-04-16

    Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO 2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a combination of environmental factors including water status, light, CO 2 levels and pathogen attack, as well as endogenous signals such as abscisic acid and apoplastic reactive oxygen species (ROS). Under abiotic and biotic stress conditions, extracellular ROS are mainly produced by plasma membrane-localized NADPH oxidases, whereas intracellular ROS are produced in multiple organelles. These ROS form a sophisticated cellular signaling network, with the accumulation of apoplastic ROS an early hallmark of stomatal movement. Here, we review recent progress in understanding the molecular mechanisms of the ROS signaling network, primarily during drought stress and pathogen attack. We summarize the roles of apoplastic ROS in regulating stomatal movement, ABA and CO 2 signaling, and immunity responses. Finally, we discuss ROS accumulation and communication between organelles and cells. This information provides a conceptual framework for understanding how ROS signaling is integrated with various signaling pathways during plant responses to abiotic and biotic stress stimuli. This article is protected by copyright. All rights reserved.

  13. Stress proteins and the immune response.

    Science.gov (United States)

    Moseley, P

    2000-07-25

    The heat shock or stress response is one of the most highly conserved adaptive responses in nature. In single cell organisms, the stress response confers tolerance to a variety of stresses including hyperthermia, hyperoxia, hypoxia, and other perturbations, which alter protein synthesis. This tolerance phenomenon is also extremely important in the multicellular organism, resulting in not only thermal tolerance, but also resistance to stresses of the whole organism such as ischemia-reperfusion injury. Moreover, recent data indicates that these stress proteins have the ability to modulate the cellular immune response. Although the terms heat shock proteins (HSPs) and stress proteins are often used interchangeably, the term stress proteins includes the HSPs, the glucose-regulated proteins (GRPs) and ubiquitin. The stress proteins may be grouped by molecular weight ranging from the large 110 kDa HSP110 to ubiquitin at 8 kDa. These proteins serve as cellular chaperones, participating in protein synthesis and transport through the various cellular compartments. Because these proteins have unique cellular localizations, the chaperone function of the stress proteins often involves a transfer of peptides between stress proteins as the peptide is moved between cellular compartments. For example, HSP70 is a cytosolic and nuclear chaperone, which is critical for the transfer of cellular peptides in the mitochondrion through a hand-off that involves mitochondrial HSP60 at the inner mitochondrial membrane. Similarly, cytosolic proteins are transferred from HSP70 to gp96 as they move into the endoplasmic reticulum. The central role of the stress proteins in the transfer of peptides through the cell may be responsible for the recently recognized importance of the stress proteins in the modulation of the immune system [Feder, M.E., Hofmann, G.E., 1999. Heat-shock proteins, molecular chaperones, and the stress response: evolutionary and ecological physiology. Annu. Rev. Physiol. 61

  14. Response of Desulfovibrio vulgaris to Alkaline Stress

    Energy Technology Data Exchange (ETDEWEB)

    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).

  15. Adaptive Responses to Thermal Stress in Mammals

    Directory of Open Access Journals (Sweden)

    Yasser Lenis Sanin

    2015-12-01

    Full Text Available The environment animals have to cope with is a combination of natural factors such as temperature. Extreme changes in these factors can alter homeostasis, which can lead to thermal stress. This stress can be due to either high temperatures or low temperatures. Energy transference for thermoregulation in homoeothermic animals occurs through several mechanisms: conduction, convection, radiation and evaporation. When animals are subjected to thermal stress, physiological mechanisms are activated which may include endocrine, neuroendocrine and behavioral responses. Activation of the neuroendocrine system affects the secretion of hormones and neurotransmitters which act collectively as response mechanisms that allow them to adapt to stress. Mechanisms which have developed through evolution to allow animals to adapt to high environmental temperatures and to achieve thermo tolerance include physiological and physical changes in order to reduce food intake and metabolic heat production, to increase surface area of skin to dissipate heat, to increase blood flow to take heat from the body core to the skin and extremities to dissipate the heat, to increase numbers and activity of sweat glands, panting, water intake and color adaptation of integument system to reflect heat. Chronic exposure to thermal stress can cause disease, reduce growth, decrease productive and reproductive performance and, in extreme cases, lead to death. This paper aims to briefly explain the physical and physiological responses of mammals to thermal stress, like a tool for biological environment adaptation, emphasizing knowledge gaps and offering some recommendations to stress control for the animal production system.

  16. Abiotic and biotic responses to Milankovitch-forced megamonsoon and glacial cycles recorded in South China at the end of the Late Paleozoic Ice Age

    Science.gov (United States)

    Fang, Qiang; Wu, Huaichun; Hinnov, Linda A.; Tian, Wenqian; Wang, Xunlian; Yang, Tianshui; Li, Haiyan; Zhang, Shihong

    2018-04-01

    At the end of the Late Paleozoic Ice Age (LPIA) from late Early Permian to early Late Permian, the global climate was impacted by a prevailing megamonsoon and Gondwanan deglaciation. To better understand the abiotic and biotic responses to Milankovitch-forced climate changes during this time period, multi-element X-ray fluorescence (XRF) geochemistry analyses were conducted on 948 samples from the late Early-late Middle Permian Maokou Formation at Shangsi, South China. The Fe/Ti, S/Ti, Ba/Ti and Ca time series, which were calibrated with an existing "floating" astronomical time scale (ATS), show the entire suite of Milankovitch rhythms including 405 kyr long eccentricity, 128 and 95 kyr short eccentricity, 33 kyr obliquity and 20 kyr precession. Spectral coherency and cross-phase analysis reveals that chemical weathering (monitored by Fe/Ti) and upwelling (captured by S/Ti and Ba/Ti) are nearly antiphase in the precession band, which suggests a contrast between summer and winter monsoon intensities. Strong obliquity signal in the Ba/Ti series is proposed to derive from changes in thermohaline circulation intensity from glaciation dynamics in southern Gondwana. The abundance of foraminifer, brachiopod and ostracod faunas within the Maokou Formation were mainly controlled by the 1.1 Myr obliquity modulation cycle. The obliquity-forced high-nutrient and oxygen-depleted conditions generally produced a benthic foraminifer bloom, but threatened the brachiopod and ostracod faunas.

  17. Dehydration Stress Contributes to the Enhancement of Plant Defense Response and Mite Performance on Barley

    Directory of Open Access Journals (Sweden)

    M. E. Santamaria

    2018-04-01

    Full Text Available Under natural conditions, plants suffer different stresses simultaneously or in a sequential way. At present, the combined effect of biotic and abiotic stressors is one of the most important threats to crop production. Understanding how plants deal with the panoply of potential stresses affecting them is crucial to develop biotechnological tools to protect plants. As well as for drought stress, the economic importance of the spider mite on agriculture is expected to increase due to climate change. Barley is a host of the polyphagous spider mite Tetranychus urticae and drought produces important yield losses. To obtain insights on the combined effect of drought and mite stresses on the defensive response of this cereal, we have analyzed the transcriptomic responses of barley plants subjected to dehydration (water-deficit treatment, spider mite attack, or to the combined dehydration-spider mite stress. The expression patterns of mite-induced responsive genes included many jasmonic acid responsive genes and were quickly induced. In contrast, genes related to dehydration tolerance were later up-regulated. Besides, a higher up-regulation of mite-induced defenses was showed by the combined dehydration and mite treatment than by the individual mite stress. On the other hand, the performance of the mite in dehydration stressed and well-watered plants was tested. Despite the stronger defensive response in plants that suffer dehydration and mite stresses, the spider mite demonstrates a better performance under dehydration condition than in well-watered plants. These results highlight the complexity of the regulatory events leading to the response to a combination of stresses and emphasize the difficulties to predict their consequences on crop production.

  18. Dehydration Stress Contributes to the Enhancement of Plant Defense Response and Mite Performance on Barley

    Science.gov (United States)

    Santamaria, M. E.; Diaz, Isabel; Martinez, Manuel

    2018-01-01

    Under natural conditions, plants suffer different stresses simultaneously or in a sequential way. At present, the combined effect of biotic and abiotic stressors is one of the most important threats to crop production. Understanding how plants deal with the panoply of potential stresses affecting them is crucial to develop biotechnological tools to protect plants. As well as for drought stress, the economic importance of the spider mite on agriculture is expected to increase due to climate change. Barley is a host of the polyphagous spider mite Tetranychus urticae and drought produces important yield losses. To obtain insights on the combined effect of drought and mite stresses on the defensive response of this cereal, we have analyzed the transcriptomic responses of barley plants subjected to dehydration (water-deficit) treatment, spider mite attack, or to the combined dehydration-spider mite stress. The expression patterns of mite-induced responsive genes included many jasmonic acid responsive genes and were quickly induced. In contrast, genes related to dehydration tolerance were later up-regulated. Besides, a higher up-regulation of mite-induced defenses was showed by the combined dehydration and mite treatment than by the individual mite stress. On the other hand, the performance of the mite in dehydration stressed and well-watered plants was tested. Despite the stronger defensive response in plants that suffer dehydration and mite stresses, the spider mite demonstrates a better performance under dehydration condition than in well-watered plants. These results highlight the complexity of the regulatory events leading to the response to a combination of stresses and emphasize the difficulties to predict their consequences on crop production. PMID:29681917

  19. Tonic immobility differentiates stress responses in PTSD.

    Science.gov (United States)

    Fragkaki, Iro; Stins, John; Roelofs, Karin; Jongedijk, Ruud A; Hagenaars, Muriel A

    2016-11-01

    Tonic immobility (TI) is a state of physical immobility associated with extreme stress and the development of posttraumatic stress disorder (PTSD). However, it is unknown whether TI is associated with a distinct actual stress response, i.e., objective immobility measured by a stabilometric platform. This study made a first step in exploring this as well as differences in body sway responses between PTSD patients and healthy controls. We hypothesized that PTSD would be related to increased body sway under stress, whereas TI would be related to decreased body sway under stress. Eye closure was selected as a PTSD-relevant stress induction procedure. Body sway and heart rate (HR) were measured in 12 PTSD patients and 12 healthy controls in four conditions: (1) maintaining a stable stance with eyes open, (2) with eyes closed, (3) during a mental arithmetic task with eyes open, and (4) with eyes closed. As predicted, PTSD patients showed increased body sway from eyes open to eyes closed compared to controls and this effect was eliminated by executing the arithmetic task. Most importantly, retrospective self-reported TI was associated with lower body sway increases in PTSD and higher body sway decreases in controls from eyes-open to eyes-closed conditions. These preliminary findings suggest that eye closure has a different effect on PTSD patients than controls and that high self-reported TI might indicate a distinct stress response pattern, i.e., a proneness for immobility. It may be relevant to take such individual differences in stress-response into account in PTSD treatment.

  20. Cotton proteomics for deciphering the mechanism of environment stress response and fiber development.

    Science.gov (United States)

    Zhou, Meiliang; Sun, Guoqing; Sun, Zhanmin; Tang, Yixiong; Wu, Yanmin

    2014-06-13

    Cotton fiber is considered as the backbone of the textile industry. The productivity of cotton crop is severely hampered by the occurrence of pathogens, pests, and various environmental factors. Nevertheless, cotton plant has developed sophisticated mechanisms to respond to environment stresses to avoid detrimental effects on its growth and development. Therefore, understanding the mechanisms of cotton fiber development and environment stress response is of considerable interest for designing agriculture breeding strategies to ensure sustainable productivity. The application of proteomics technologies to advance our knowledge in cotton fiber development and abiotic/biotic stress tolerance has increased dramatically in the last 5years as evidenced by the large amount of publications in this area. This review summarizes the work which has been reported for cotton proteomics and evaluates the findings in context of the approaches that are widely employed with the aim to generate novel insight useful for cotton improvement. Cotton (Gossypium spp.) is considered as the foremost commercially important fiber crop grown all over the world and is deemed as the backbone of the textile industry. Cotton is also an important source of edible oil seed and a nutrient-rich food crop as cottonseed contains high-quality protein and oil. The growth and productivity of cotton crop are often hampered by various biotic stress factors, such as insect pests and pathogens. In addition, cotton plants are frequently subjected to unavoidable environmental factors that cause abiotic stress, such as salt, heat and drought. Proteomic techniques provide one of the best options for understanding the gene function and phenotypic changes during cotton fiber development and stress response. This review first summarizes the work which has been reported for cotton proteomics about cotton fiber development and abiotic/biotic stress tolerance, and also evaluates the findings in context of the approaches

  1. Genome wide analysis of stress responsive WRKY transcription factors in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Shaiq Sultan

    2016-04-01

    Full Text Available WRKY transcription factors are a class of DNA-binding proteins that bind with a specific sequence C/TTGACT/C known as W-Box found in promoters of genes which are regulated by these WRKYs. From previous studies, 43 different stress responsive WRKY transcription factors in Arabidopsis thaliana, identified and then categorized in three groups viz., abiotic, biotic and both of these stresses. A comprehensive genome wide analysis including chromosomal localization, gene structure analysis, multiple sequence alignment, phylogenetic analysis and promoter analysis of these WRKY genes was carried out in this study to determine the functional homology in Arabidopsis. This analysis led to the classification of these WRKY family members into 3 major groups and subgroups and showed evolutionary relationship among these groups on the base of their functional WRKY domain, chromosomal localization and intron/exon structure. The proposed groups of these stress responsive WRKY genes and annotation based on their position on chromosomes can also be explored to determine their functional homology in other plant species in relation to different stresses. The result of the present study provides indispensable genomic information for the stress responsive WRKY transcription factors in Arabidopsis and will pave the way to explain the precise role of various AtWRKYs in plant growth and development under stressed conditions.

  2. The War Fighter's Stress Response: Telemetric and Noninvasive Assessment

    National Research Council Canada - National Science Library

    O'Donnell, Amanda

    2003-01-01

    ... and biological responses to stress. Specifically, stress-hardy individuals retain mental focus and clarity of memory under stress, commit fewer errors during stress, experience less burnout, demonstrate better navigational skills...

  3. Roots Withstanding their Environment: Exploiting Root System Architecture Responses to Abiotic Stress to Improve Crop Tolerance

    Science.gov (United States)

    Koevoets, Iko T.; Venema, Jan Henk; Elzenga, J. Theo. M.; Testerink, Christa

    2016-01-01

    To face future challenges in crop production dictated by global climate changes, breeders and plant researchers collaborate to develop productive crops that are able to withstand a wide range of biotic and abiotic stresses. However, crop selection is often focused on shoot performance alone, as observation of root properties is more complex and asks for artificial and extensive phenotyping platforms. In addition, most root research focuses on development, while a direct link to the functionality of plasticity in root development for tolerance is often lacking. In this paper we review the currently known root system architecture (RSA) responses in Arabidopsis and a number of crop species to a range of abiotic stresses, including nutrient limitation, drought, salinity, flooding, and extreme temperatures. For each of these stresses, the key molecular and cellular mechanisms underlying the RSA response are highlighted. To explore the relevance for crop selection, we especially review and discuss studies linking root architectural responses to stress tolerance. This will provide a first step toward understanding the relevance of adaptive root development for a plant’s response to its environment. We suggest that functional evidence on the role of root plasticity will support breeders in their efforts to include root properties in their current selection pipeline for abiotic stress tolerance, aimed to improve the robustness of crops. PMID:27630659

  4. The exoribonuclease Polynucleotide Phosphorylase influences the virulence and stress responses of yersiniae and many other pathogens

    Directory of Open Access Journals (Sweden)

    Jason A. Rosenzweig

    2013-11-01

    Full Text Available Microbes are incessantly challenged by both biotic and abiotic stressors threatening their existence. Therefore, bacterial pathogens must possess mechanisms to successfully subvert host immune defenses as well as overcome the stress associated with host-cell encounters. To achieve this, bacterial pathogens typically experience a genetic re-programming whereby anti-host/stress factors become expressed and eventually translated into effector proteins. In that vein, the bacterial host-cell induced stress-response is similar to any other abiotic stress to which bacteria respond by up-regulating specific stress-responsive genes. Following the stress encounter, bacteria must degrade unnecessary stress responsive transcripts through RNA decay mechanisms. The 3 pathogenic yersiniae (Yersinia pestis, Y. pseudo-tuberculosis, and Y. enterocolitica are all psychrotropic bacteria capable of growth at 4˚C; however, cold growth is dependent on the presence of an exoribonuclease, polynucleotide phosphorylase (PNPase. PNPase has also been implicated as a virulence factor in several notable pathogens including the salmonellae, Helicobacter pylori, and the yersiniae (where it typically influences the type three secretion system. Further, PNPase has been shown to associate with ribonuclease E (endoribonuclease, RhlB (RNA helicase, and enolase (glycolytic enzyme in several Gram-negative bacteria forming a large, multi-protein complex known as the RNA degradosome. This review will highlight studies demonstrating the influence of PNPase on the virulence potentials and stress responses of various bacterial pathogens as well as focusing on the degradosome- dependent and -independent roles played by PNPase in yersiniae stress responses.

  5. Dysfunctional stress responses in chronic pain.

    Science.gov (United States)

    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Stress response in medically important Mucorales.

    Science.gov (United States)

    Singh, Pankaj; Paul, Saikat; Shivaprakash, M Rudramurthy; Chakrabarti, Arunaloke; Ghosh, Anup K

    2016-10-01

    Mucorales are saprobes, ubiquitously distributed and able to infect a heterogeneous population of human hosts. The fungi require robust stress responses to survive in human host. We tested the growth of Mucorales in the presence of different abiotic stress. Eight pathogenic species of Mucorales, including Rhizopus arrhizus, Rhizopus microsporus, Rhizomucor pusillus, Apophysomyces elegans, Licthemia corymbifera, Cunninghamella bertholletiae, Syncephalastrum racemosum and Mucor racemosus, were exposed to different stress inducers: osmotic (sodium chloride and d-sorbitol), oxidative (hydrogen peroxide and menadione), pH, cell wall and metal ions (Cu, Zn, Fe and Mg). Wide variation in stress responses was noted: R. arrhizus showed maximum resistance to both osmotic and oxidative stresses, whereas R. pusillus and M. indicus were relatively sensitive. Rhizopus arrhizus and R. microsporus showed maximum resistance to alkaline pH, whereas C. bertholletiae, L. corymbifera, M. racemosus and A. elegans were resistant to acidic pH. Maximum tolerance was noted in R. microsporus to Cu, R. microsporus and R. arrhizus to Fe and C. bertholletiae to Zn. In contrast, L. corymbifera, A. elegans and M. indicus were sensitive to Cu, Zn and Fe respectively. In conclusion, R. arrhizus showed high stress tolerance in comparison to other species of Mucorales, and this could be the possible reason for high pathogenic potential of this fungi. © 2016 Blackwell Verlag GmbH.

  7. Sympathoneural and Adrenomedullary Responses to Mental Stress

    Science.gov (United States)

    Carter, Jason R.; Goldstein, David S.

    2017-01-01

    This concept-based review provides historical perspectives and updates about sympathetic noradrenergic and sympathetic adrenergic responses to mental stress. The topic of this review has incited perennial debate, because of disagreements over definitions, controversial inferences, and limited availability of relevant measurement tools. The discussion begins appropriately with Cannon's "homeostasis" and his pioneering work in the area. This is followed by mental stress as a scientific idea and the relatively new notions of allostasis and allostatic load. Experimental models of mental stress in rodents and humans are discussed, with particular attention to ethical constraints in humans. Sections follow on sympathoneural to mental stress, reactivity of catecholamine systems, clinical pathophysiologic states, and the cardiovascular reactivity hypothesis. Future advancement of the field will require integrative approaches and coordinated efforts between physiologists and psychologists on this interdisciplinary topic. PMID:25589266

  8. Plant Nucleolar Stress Response, a New Face in the NAC-Dependent Cellular Stress Responses.

    Science.gov (United States)

    Ohbayashi, Iwai; Sugiyama, Munetaka

    2017-01-01

    The nucleolus is the most prominent nuclear domain, where the core processes of ribosome biogenesis occur vigorously. All these processes are finely orchestrated by many nucleolar factors to build precisely ribosome particles. In animal cells, perturbations of ribosome biogenesis, mostly accompanied by structural disorders of the nucleolus, cause a kind of cellular stress to induce cell cycle arrest, senescence, or apoptosis, which is called nucleolar stress response. The best-characterized pathway of this stress response involves p53 and MDM2 as key players. p53 is a crucial transcription factor that functions in response to not only nucleolar stress but also other cellular stresses such as DNA damage stress. These cellular stresses release p53 from the inhibition by MDM2, an E3 ubiquitin ligase targeting p53, in various ways, which leads to p53-dependent activation of a set of genes. In plants, genetic impairments of ribosome biogenesis factors or ribosome components have been shown to cause characteristic phenotypes, including a narrow and pointed leaf shape, implying a common signaling pathway connecting ribosomal perturbations and certain aspects of growth and development. Unlike animals, however, plants have neither p53 nor MDM2 family proteins. Then the question arises whether plant cells have a nucleolar stress response pathway. In recent years, it has been reported that several members of the plant-specific transcription factor family NAC play critical roles in the pathways responsive to various cellular stresses. In this mini review, we outline the plant cellular stress response pathways involving NAC transcription factors with reference to the p53-MDM2-dependent pathways of animal cells, and discuss the possible involvement of a plant-unique, NAC-mediated pathway in the nucleolar stress response in plants.

  9. Plant Nucleolar Stress Response, a New Face in the NAC-Dependent Cellular Stress Responses

    Directory of Open Access Journals (Sweden)

    Iwai Ohbayashi

    2018-01-01

    Full Text Available The nucleolus is the most prominent nuclear domain, where the core processes of ribosome biogenesis occur vigorously. All these processes are finely orchestrated by many nucleolar factors to build precisely ribosome particles. In animal cells, perturbations of ribosome biogenesis, mostly accompanied by structural disorders of the nucleolus, cause a kind of cellular stress to induce cell cycle arrest, senescence, or apoptosis, which is called nucleolar stress response. The best-characterized pathway of this stress response involves p53 and MDM2 as key players. p53 is a crucial transcription factor that functions in response to not only nucleolar stress but also other cellular stresses such as DNA damage stress. These cellular stresses release p53 from the inhibition by MDM2, an E3 ubiquitin ligase targeting p53, in various ways, which leads to p53-dependent activation of a set of genes. In plants, genetic impairments of ribosome biogenesis factors or ribosome components have been shown to cause characteristic phenotypes, including a narrow and pointed leaf shape, implying a common signaling pathway connecting ribosomal perturbations and certain aspects of growth and development. Unlike animals, however, plants have neither p53 nor MDM2 family proteins. Then the question arises whether plant cells have a nucleolar stress response pathway. In recent years, it has been reported that several members of the plant-specific transcription factor family NAC play critical roles in the pathways responsive to various cellular stresses. In this mini review, we outline the plant cellular stress response pathways involving NAC transcription factors with reference to the p53-MDM2-dependent pathways of animal cells, and discuss the possible involvement of a plant-unique, NAC-mediated pathway in the nucleolar stress response in plants.

  10. Nitric oxide-activated hydrogen sulfide is essential for cadmium stress response in bermudagrass (Cynodon dactylon (L). Pers.).

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Chan, Zhulong

    2014-01-01

    Nitric oxide (NO) and hydrogen sulfide (H2S) are important gaseous molecules, serving as important secondary messengers in plant response to various biotic and abiotic stresses. However, the interaction between NO and H2S in plant stress response was largely unclear. In this study, endogenous NO and H2S were evidently induced by cadmium stress treatment in bermudagrass, and exogenous applications of NO donor (sodium nitroprusside, SNP) or H2S donor (sodium hydrosulfide, NaHS) conferred improved cadmium stress tolerance. Additionally, SNP and NaHS treatments alleviated cadmium stress-triggered plant growth inhibition, cell damage and reactive oxygen species (ROS) burst, partly via modulating enzymatic and non-enzymatic antioxidants. Moreover, SNP and NaHS treatments also induced the productions of both NO and H2S in the presence of Cd. Interestingly, combined treatments with inhibitors and scavengers of NO and H2S under cadmium stress condition showed that NO signal could be blocked by both NO and H2S inhibitors and scavengers, while H2S signal was specifically blocked by H2S inhibitors and scavengers, indicating that NO-activated H2S was essential for cadmium stress response. Taken together, we assigned the protective roles of endogenous and exogenous NO and H2S in bermudagrass response to cadmium stress, and speculated that NO-activated H2S might be essential for cadmium stress response in bermudagrass. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  11. The endoplasmic reticulum stress response in disease ...

    African Journals Online (AJOL)

    These proteins are essential for cell survival, and intuitively the ER must activate stress responses to evade immediate cell dysfunction as the cell processes lag behind. This review will discuss mainly the ER and its role in the pathogenesis and pathophysiology of epidemiologically-relevant diseases, as well as updates on ...

  12. Dynamic response of plant genome to ultraviolet radiation and other genotoxic stresses

    International Nuclear Information System (INIS)

    Molinier, Jean; Oakeley, Edward J.; Niederhauser, Olivier; Kovalchuk, Igor; Hohn, Barbara

    2005-01-01

    Oligonucleotide microarray technology was used to identify genes, which are responding after exposure to UV-C radiation and to other agents causing genotoxic stress. The effect of these conditions on recombinational DNA repair was monitored in parallel. Global changes in gene expression were investigated in Arabidopsis wild-type plants challenged with UV-C, bleomycin, another abiotic agent and xylanase, a biotic factor, all leading to elevated homologous recombination frequencies. The comparison of the expression profile of each treatment allowed defining genes specifically involved in the dynamic response to UV. In the future, the potential roles of such genes in the different forms of stress recognition, signal transduction, and their roles in DNA repair processes will be assessed by using reverse genetic tools available for Arabidopsis thaliana

  13. Transcriptional responses of Medicago truncatula upon sulfur deficiency stress and arbuscular mycorrhizal symbios

    Directory of Open Access Journals (Sweden)

    Daniel eWipf

    2014-12-01

    Full Text Available Sulfur plays an essential role in plants’ growth and development and in their response to various abiotic and biotic stresses despite its leachability and its very low abundance in the only form that plant roots can uptake (sulfate. It is part of amino acids, glutathione (GSH, thiols of proteins and peptides, membrane sulfolipids, cell walls and secondary products, so reduced availability can drastically alter plant growth and development. The nutritional benefits of symbiotic interactions can help the plant in case of S deficiency. In particular the arbuscular mycorrhizal (AM interaction improves N, P and S plant nutrition, but the mechanisms behind these exchanges are not fully known yet. Although the transcriptional changes in the leguminous model plant Medicago truncatula have been already assessed in several biotic and/or abiotic conditions, S deficiency has not been considered so far. The aim of this work is to get a first overview on S-deficiency responses in the leaf and root tissues of plants interacting with the AM fungus Rhizophagus irregularis.Several hundred genes displayed significantly different transcript accumulation levels. Annotation and GO ID association were used to identify biological processes and molecular functions affected by sulfur starvation. Beside the beneficial effects of AM interaction, plants were greatly affected by the nutritional status, showing various differences in their transcriptomic footprints. Several pathways in which S plays an important role appeared to be differentially affected according to mycorrhizal status, with a generally reduced responsiveness to S deficiency in mycorrhized plants.

  14. Work stress and innate immune response.

    Science.gov (United States)

    Boscolo, P; Di Gioacchino, M; Reale, M; Muraro, R; Di Giampaolo, L

    2011-01-01

    Several reports highlight the relationship between blood NK cytotoxic activity and life style. Easy life style, including physical activity, healthy dietary habits as well as good mental health are characterized by an efficient immune response. Life style is related to the type of occupational activity since work has a central part in life either as source of income or contributing to represent the social identity. Not only occupational stress, but also job loss or insecurity are thus considered serious stressful situations, inducing emotional disorders which may affect both neuroendocrine and immune systems; reduced reactivity to mitogens and/or decreased blood NK cytotoxic activity was reported in unemployed workers or in those with a high perception of job insecurity and/or job stress. Although genetic factors have a key role in the pathogenesis of autoimmune disorders, occupational stress (as in night shifts) was reported associated to an increased incidence of autoimmune disorders. Monitoring blood NK response may thus be included in the health programs as an indirect index of stressful job and/or poor lifestyle.

  15. DAE-BRNS life sciences symposium on molecular biology of stress response and its applications

    International Nuclear Information System (INIS)

    2005-01-01

    The world of living organisms is full of challenges from their surroundings and these organisms learn to adapt themselves to the changes - some transient and some permanent - in these surroundings. The demands on adaptability to stress are very strong for extremophiles that live in harsh conditions such as cold or hot temperatures, salinity and hyperbaric habitats. The stress could be biotic (e.g. infection or parasitism) or abiotic (e.g. temperature, light, salinity, heavy metals etc.) Evolutionarily living organisms have developed different shapes, coloration, habits etc. to survive in their habitats. The molecular mechanisms of these biological adaptations have become clearer only in recent years from the studies on the biological responses of an organism to stresses during its life time. Such responses are characterized by activation of certain genes and synthesis of proteins and metabolites, which facilitate amelioration of the stress. The molecular biology (biochemistry and genetics) of stress response is being constantly unravelled thanks to the availability of highly sensitive and high throughput techniques and a plethora of extremophilic experimental systems such as archaebacteria, radio resistant bacteria and midges, plants surviving in cold etc. An interesting outcome of this voluminous research has been the knowledge that responses to a group of stresses share common mechanisms, at least in part. This reflects the biologically conservationist trend among otherwise diverse organisms and stresses. In this symposium several papers and posters in the area of molecular biology of stress are presented in addition to some very interesting and promising-to-be informative and stimulating plenary lectures and invited talks from highly reputed scientists. The papers relevant to INIS are indexed separately

  16. Hydrogen peroxide and polyamines act as double edged swords in plant abiotic stress responses

    Directory of Open Access Journals (Sweden)

    Kamala Gupta

    2016-09-01

    Full Text Available The specific genetic changes through which plants adapt to the multitude of environmental stresses are possible because of the molecular regulations in the system. These intricate regulatory mechanisms once unveiled will surely raise interesting questions. Polyamines and hydrogen peroxide have been suggested to be important signalling molecules during biotic and abiotic stresses. Hydrogen peroxide plays a versatile role from orchestrating physiological processes to stress response. It helps to achieve acclimatization and tolerance to stress by coordinating intra-cellular and systemic signalling systems. Polyamines, on the other hand, are low molecular weight polycationic aliphatic amines, which have been implicated in various stress responses. It is quite interesting to note that both hydrogen peroxide and polyamines have a fine line of inter-relation between them since the catabolic pathways of the latter releases hydrogen peroxide. In this review we have tried to illustrate the roles and their multifaceted functions of these two important signalling molecules based on current literature. This review also highlights the fact that over accumulation of hydrogen peroxide and polyamines can be detrimental for plant cells leading to toxicity and pre-mature cell death.

  17. Hydrogen Peroxide and Polyamines Act as Double Edged Swords in Plant Abiotic Stress Responses.

    Science.gov (United States)

    Gupta, Kamala; Sengupta, Atreyee; Chakraborty, Mayukh; Gupta, Bhaskar

    2016-01-01

    The specific genetic changes through which plants adapt to the multitude of environmental stresses are possible because of the molecular regulations in the system. These intricate regulatory mechanisms once unveiled will surely raise interesting questions. Polyamines and hydrogen peroxide have been suggested to be important signaling molecules during biotic and abiotic stresses. Hydrogen peroxide plays a versatile role from orchestrating physiological processes to stress response. It helps to achieve acclimatization and tolerance to stress by coordinating intra-cellular and systemic signaling systems. Polyamines, on the other hand, are low molecular weight polycationic aliphatic amines, which have been implicated in various stress responses. It is quite interesting to note that both hydrogen peroxide and polyamines have a fine line of inter-relation between them since the catabolic pathways of the latter releases hydrogen peroxide. In this review we have tried to illustrate the roles and their multifaceted functions of these two important signaling molecules based on current literature. This review also highlights the fact that over accumulation of hydrogen peroxide and polyamines can be detrimental for plant cells leading to toxicity and pre-mature cell death.

  18. Physiological Responses to Thermal Stress and Exercise

    Science.gov (United States)

    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.

  19. Everyday stress response targets in the science of behavior change.

    Science.gov (United States)

    Smyth, Joshua M; Sliwinski, Martin J; Zawadzki, Matthew J; Scott, Stacey B; Conroy, David E; Lanza, Stephanie T; Marcusson-Clavertz, David; Kim, Jinhyuk; Stawski, Robert S; Stoney, Catherine M; Buxton, Orfeu M; Sciamanna, Christopher N; Green, Paige M; Almeida, David M

    2018-02-01

    Stress is an established risk factor for negative health outcomes, and responses to everyday stress can interfere with health behaviors such as exercise and sleep. In accordance with the Science of Behavior Change (SOBC) program, we apply an experimental medicine approach to identifying stress response targets, developing stress response assays, intervening upon these targets, and testing intervention effectiveness. We evaluate an ecologically valid, within-person approach to measuring the deleterious effects of everyday stress on physical activity and sleep patterns, examining multiple stress response components (i.e., stress reactivity, stress recovery, and stress pile-up) as indexed by two key response indicators (negative affect and perseverative cognition). Our everyday stress response assay thus measures multiple malleable stress response targets that putatively shape daily health behaviors (physical activity and sleep). We hypothesize that larger reactivity, incomplete recovery, and more frequent stress responses (pile-up) will negatively impact health behavior enactment in daily life. We will identify stress-related reactivity, recovery, and response in the indicators using coordinated analyses across multiple naturalistic studies. These results are the basis for developing a new stress assay and replicating the initial findings in a new sample. This approach will advance our understanding of how specific aspects of everyday stress responses influence health behaviors, and can be used to develop and test an innovative ambulatory intervention for stress reduction in daily life to enhance health behaviors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Abiotic stress responses in plants: roles of calmodulin-regulated proteins

    Science.gov (United States)

    Virdi, Amardeep S.; Singh, Supreet; Singh, Prabhjeet

    2015-01-01

    Intracellular changes in calcium ions (Ca2+) in response to different biotic and abiotic stimuli are detected by various sensor proteins in the plant cell. Calmodulin (CaM) is one of the most extensively studied Ca2+-sensing proteins and has been shown to be involved in transduction of Ca2+ signals. After interacting with Ca2+, CaM undergoes conformational change and influences the activities of a diverse range of CaM-binding proteins. A number of CaM-binding proteins have also been implicated in stress responses in plants, highlighting the central role played by CaM in adaptation to adverse environmental conditions. Stress adaptation in plants is a highly complex and multigenic response. Identification and characterization of CaM-modulated proteins in relation to different abiotic stresses could, therefore, prove to be essential for a deeper understanding of the molecular mechanisms involved in abiotic stress tolerance in plants. Various studies have revealed involvement of CaM in regulation of metal ions uptake, generation of reactive oxygen species and modulation of transcription factors such as CAMTA3, GTL1, and WRKY39. Activities of several kinases and phosphatases have also been shown to be modulated by CaM, thus providing further versatility to stress-associated signal transduction pathways. The results obtained from contemporary studies are consistent with the proposed role of CaM as an integrator of different stress signaling pathways, which allows plants to maintain homeostasis between different cellular processes. In this review, we have attempted to present the current state of understanding of the role of CaM in modulating different stress-regulated proteins and its implications in augmenting abiotic stress tolerance in plants. PMID:26528296

  1. Identification and Characterization of Wilt and Salt Stress-Responsive MicroRNAs in Chickpea through High-Throughput Sequencing

    Science.gov (United States)

    Deokar, Amit Atmaram; Bhardwaj, Ankur R.; Agarwal, Manu; Katiyar-Agarwal, Surekha; Srinivasan, Ramamurthy; Jain, Pradeep Kumar

    2014-01-01

    Chickpea (Cicer arietinum) is the second most widely grown legume worldwide and is the most important pulse crop in the Indian subcontinent. Chickpea productivity is adversely affected by a large number of biotic and abiotic stresses. MicroRNAs (miRNAs) have been implicated in the regulation of plant responses to several biotic and abiotic stresses. This study is the first attempt to identify chickpea miRNAs that are associated with biotic and abiotic stresses. The wilt infection that is caused by the fungus Fusarium oxysporum f.sp. ciceris is one of the major diseases severely affecting chickpea yields. Of late, increasing soil salinization has become a major problem in realizing these potential yields. Three chickpea libraries using fungal-infected, salt-treated and untreated seedlings were constructed and sequenced using next-generation sequencing technology. A total of 12,135,571 unique reads were obtained. In addition to 122 conserved miRNAs belonging to 25 different families, 59 novel miRNAs along with their star sequences were identified. Four legume-specific miRNAs, including miR5213, miR5232, miR2111 and miR2118, were found in all of the libraries. Poly(A)-based qRT-PCR (Quantitative real-time PCR) was used to validate eleven conserved and five novel miRNAs. miR530 was highly up regulated in response to fungal infection, which targets genes encoding zinc knuckle- and microtubule-associated proteins. Many miRNAs responded in a similar fashion under both biotic and abiotic stresses, indicating the existence of cross talk between the pathways that are involved in regulating these stresses. The potential target genes for the conserved and novel miRNAs were predicted based on sequence homologies. miR166 targets a HD-ZIPIII transcription factor and was validated by 5′ RLM-RACE. This study has identified several conserved and novel miRNAs in the chickpea that are associated with gene regulation following exposure to wilt and salt stress. PMID:25295754

  2. Identifying salt stress-responsive transcripts from Roselle ( Hibiscus ...

    African Journals Online (AJOL)

    Hibiscus sabdariffa L.). Identifying the potentially novel transcripts responsible for salt stress tolerance in roselle will increase knowledge of the molecular mechanism underlying salt stress responses. In this study, differential display reverse ...

  3. Growth and physiological responses to water and nutrient stress in ...

    African Journals Online (AJOL)

    Growth and physiological responses to water and nutrient stress in oil palm. ... changes in growth, physiology and nutrient concentration in response to two watering regimes (well-watered and water-stress conditions) and ... from 32 Countries:.

  4. Bacillus amyloliquefaciens Confers Tolerance to Various Abiotic Stresses and Modulates Plant Response to Phytohormones through Osmoprotection and Gene Expression Regulation in Rice

    Directory of Open Access Journals (Sweden)

    Shalini Tiwari

    2017-08-01

    Full Text Available Being sessile in nature, plants have to withstand various adverse environmental stress conditions including both biotic and abiotic stresses. Comparatively, abiotic stresses such as drought, salinity, high temperature, and cold pose major threat to agriculture by negatively impacting plant growth and yield worldwide. Rice is one of the most widely consumed staple cereals across the globe, the production and productivity of which is also severely affected by different abiotic stresses. Therefore, several crop improvement programs are directed toward developing stress tolerant rice cultivars either through marker assisted breeding or transgenic technology. Alternatively, some known rhizospheric competent bacteria are also known to improve plant growth during abiotic stresses. A plant growth promoting rhizobacteria (PGPR, Bacillus amyloliquefaciens NBRI-SN13 (SN13 was previously reported by our lab to confer salt stress tolerance to rice seedlings. However, the present study investigates the role of SN13 in ameliorating various abiotic stresses such as salt, drought, desiccation, heat, cold, and freezing on a popular rice cv. Saryu-52 under hydroponic growth conditions. Apart from this, seedlings were also exogenously supplied with abscisic acid (ABA, salicylic acid (SA, jasmonic acid (JA and ethephon (ET to study the role of SN13 in phytohormone-induced stress tolerance as well as its role in abiotic and biotic stress cross-talk. All abiotic stresses and phytohormone treatments significantly affected various physiological and biochemical parameters like membrane integrity and osmolyte accumulation. SN13 also positively modulated stress-responsive gene expressions under various abiotic stresses and phytohormone treatments suggesting its multifaceted role in cross-talk among stresses and phytohormones in response to PGPR. To the best of our knowledge, this is the first report on detailed analysis of plant growth promotion and stress alleviation by a

  5. Kunitz Proteinase Inhibitors Limit Water Stress Responses in White Clover (Trifolium repens L.) Plants.

    Science.gov (United States)

    Islam, Afsana; Leung, Susanna; Nikmatullah, Aluh; Dijkwel, Paul P; McManus, Michael T

    2017-01-01

    The response of plants to water deficiency or drought is a complex process, the perception of which is triggered at the molecular level before any visible morphological responses are detected. It was found that different groups of plant proteinase inhibitors (PIs) are induced and play an active role during abiotic stress conditions such as drought. Our previous work with the white clover ( Trifolium repens L.) Kunitz Proteinase Inhibitor ( Tr-KPI ) gene family showed that Tr-KPIs are differentially regulated to ontogenetic and biotic stress associated cues and that, at least some members of this gene family may be required to maintain cellular homeostasis. Altered cellular homeostasis may also affect abiotic stress responses and therefore, we aimed to understand if distinct Tr-PKI members function during drought stress. First, the expression level of three Tr-KPI genes, Tr-KPI1 , Tr-KPI2 , and Tr-KPI5 , was measured in two cultivars and one white clover ecotype with differing capacity to tolerate drought. The expression of Tr-KPI1 and Tr-KPI5 increased in response to water deficiency and this was exaggerated when the plants were treated with a previous period of water deficiency. In contrast, proline accumulation and increased expression of Tr-NCED1 , a gene encoding a protein involved in ABA biosynthesis, was delayed in plants that experienced a previous drought period. RNAi knock-down of Tr-KPI1 and Tr-KPI5 resulted in increased proline accumulation in leaf tissue of plants grown under both well-watered and water-deficit conditions. In addition, increased expression of genes involved in ethylene biosynthesis was found. The data suggests that Tr-KPIs , particularly Tr-KPI5 , have an explicit function during water limitation. The results also imply that the Tr-KPI family has different in planta proteinase targets and that the functions of this protein family are not solely restricted to one of storage proteins or in response to biotic stress.

  6. Kunitz Proteinase Inhibitors Limit Water Stress Responses in White Clover (Trifolium repens L. Plants

    Directory of Open Access Journals (Sweden)

    Afsana Islam

    2017-10-01

    Full Text Available The response of plants to water deficiency or drought is a complex process, the perception of which is triggered at the molecular level before any visible morphological responses are detected. It was found that different groups of plant proteinase inhibitors (PIs are induced and play an active role during abiotic stress conditions such as drought. Our previous work with the white clover (Trifolium repens L. Kunitz Proteinase Inhibitor (Tr-KPI gene family showed that Tr-KPIs are differentially regulated to ontogenetic and biotic stress associated cues and that, at least some members of this gene family may be required to maintain cellular homeostasis. Altered cellular homeostasis may also affect abiotic stress responses and therefore, we aimed to understand if distinct Tr-PKI members function during drought stress. First, the expression level of three Tr-KPI genes, Tr-KPI1, Tr-KPI2, and Tr-KPI5, was measured in two cultivars and one white clover ecotype with differing capacity to tolerate drought. The expression of Tr-KPI1 and Tr-KPI5 increased in response to water deficiency and this was exaggerated when the plants were treated with a previous period of water deficiency. In contrast, proline accumulation and increased expression of Tr-NCED1, a gene encoding a protein involved in ABA biosynthesis, was delayed in plants that experienced a previous drought period. RNAi knock-down of Tr-KPI1 and Tr-KPI5 resulted in increased proline accumulation in leaf tissue of plants grown under both well-watered and water-deficit conditions. In addition, increased expression of genes involved in ethylene biosynthesis was found. The data suggests that Tr-KPIs, particularly Tr-KPI5, have an explicit function during water limitation. The results also imply that the Tr-KPI family has different in planta proteinase targets and that the functions of this protein family are not solely restricted to one of storage proteins or in response to biotic stress.

  7. Plant Nucleolar Stress Response, a New Face in the NAC-Dependent Cellular Stress Responses

    OpenAIRE

    Iwai Ohbayashi; Munetaka Sugiyama

    2018-01-01

    The nucleolus is the most prominent nuclear domain, where the core processes of ribosome biogenesis occur vigorously. All these processes are finely orchestrated by many nucleolar factors to build precisely ribosome particles. In animal cells, perturbations of ribosome biogenesis, mostly accompanied by structural disorders of the nucleolus, cause a kind of cellular stress to induce cell cycle arrest, senescence, or apoptosis, which is called nucleolar stress response. The best-characterized p...

  8. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

    Science.gov (United States)

    Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

    2016-01-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage. PMID:27053445

  9. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways.

    Science.gov (United States)

    Dues, Dylan J; Andrews, Emily K; Schaar, Claire E; Bergsma, Alexis L; Senchuk, Megan M; Van Raamsdonk, Jeremy M

    2016-04-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage.

  10. Abscisic Acid and Gibberellins Antagonistically Mediate Plant Development and Abiotic Stress Responses

    Directory of Open Access Journals (Sweden)

    Kai Shu

    2018-03-01

    Full Text Available Phytohormones regulate numerous important biological processes in plant development and biotic/abiotic stress response cascades. More than 50 and 100 years have passed since the initial discoveries of the phytohormones abscisic acid (ABA and gibberellins (GA, respectively. Over the past several decades, numerous elegant studies have demonstrated that ABA and GA antagonistically regulate many plant developmental processes, including seed maturation, seed dormancy and germination, root initiation, hypocotyl and stem elongation, and floral transition. Furthermore, as a well-established stress hormone, ABA plays a key role in plant responses to abiotic stresses, such as drought, flooding, salinity and low temperature. Interestingly, recent evidence revealed that GA are also involved in plant response to adverse environmental conditions. Consequently, the complex crosstalk networks between ABA and GA, mediated by diverse key regulators, have been extensively investigated and documented. In this updated mini-review, we summarize the most recent advances in our understanding of the antagonistically regulatory roles of ABA and GA in different stages of plant development and in various plant–environment interactions, focusing on the crosstalk between ABA and GA at the levels of phytohormone metabolism and signal transduction.

  11. Opposite Effects of Stress on Pain Modulation Depend on the Magnitude of Individual Stress Response.

    Science.gov (United States)

    Geva, Nirit; Defrin, Ruth

    2018-04-01

    The effect of acute stress on pain threshold and intolerance threshold are reported as producing either hypoalgesia or hyperalgesia. Yet, the contribution of individual stress reactivity in this respect has not been established. The aim was to test 2 pain modulation paradigms under acute stress manipulation, to our knowledge, for the first time, to study whether stress differentially affects pain modulation, and whether the effect is related to individual stress response. Participants were 31 healthy subjects. Conditioned pain modulation (CPM) and pain adaptation were measured before and after inducing an acute stress response using the Montreal Imaging Stress Task. Subjects' stress response was evaluated according to salivary cortisol, autonomic function, and perceived stress and anxiety. The Montreal Imaging Stress Task induced a validated stress response. On a group level, stress induced reduction in CPM magnitude and increase in pain adaptation compared with baseline. These responses correlated with stress reactivity. When the group was subdivided according to stress reactivity, only high stress responders exhibited reduced CPM whereas only low stress responders exhibited increased pain adaptation. The results suggest that acute stress may induce opposite effects on pain modulation, depending on individual stress reactivity magnitude, with an advantage to low stress responders. This study evaluated the effect of acute stress on pain modulation. Pain modulation under stress is affected by individual stress responsiveness; decreased CPM occurs in high stress responders whereas increased pain adaptation occurs in low stress responders. Identification of high stress responders may promote better pain management. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

  12. Genetic architecture of plant stress resistance : Multi-trait genome-wide association mapping

    NARCIS (Netherlands)

    Thoen, Manus P M; Davila Olivas, Nelson H.; Kloth, Karen J.; Coolen, Silvia; Huang, Ping Ping; Aarts, Mark G M; Bac-Molenaar, Johanna A.; Bakker, Jaap; Bouwmeester, Harro J.; Broekgaarden, Colette; Bucher, Johan; Busscher-Lange, Jacqueline; Cheng, Xi; Fradin, Emilie F.; Jongsma, Maarten A.; Julkowska, Magdalena M.; Keurentjes, Joost J B; Ligterink, Wilco; Pieterse, Corné M J; Ruyter-Spira, Carolien; Smant, Geert; Testerink, Christa; Usadel, Björn; van Loon, Joop J A; van Pelt, Johan A.; van Schaik, Casper C.; van Wees, Saskia C M; Visser, Richard G F; Voorrips, Roeland; Vosman, Ben; Vreugdenhil, Dick; Warmerdam, Sonja; Wiegers, Gerrie L.; van Heerwaarden, Joost; Kruijer, Willem; van Eeuwijk, Fred A.; Dicke, Marcel

    2017-01-01

    Plants are exposed to combinations of various biotic and abiotic stresses, but stress responses are usually investigated for single stresses only. Here, we investigated the genetic architecture underlying plant responses to 11 single stresses and several of their combinations by phenotyping 350

  13. Personality traits modulate emotional and physiological responses to stress.

    Science.gov (United States)

    Childs, Emma; White, Tara L; de Wit, Harriet

    2014-09-01

    An individual's susceptibility to psychological and physical disorders associated with chronic stress exposure, for example, cardiovascular and infectious disease, may also be predicted by their reactivity to acute stress. One factor associated with both stress resilience and health outcomes is personality. An understanding of how personality influences responses to acute stress may shed light upon individual differences in susceptibility to chronic stress-linked disease. This study examined the relationships between personality and acute responses to stress in 125 healthy adults, using hierarchical linear regression. We assessed personality traits using the Multidimensional Personality Questionnaire (MPQ-BF), and responses to acute stress (cortisol, heart rate, blood pressure, mood) using a standardized laboratory psychosocial stress task, the Trier Social Stress Test. Individuals with high Negative Emotionality exhibited greater emotional distress and lower blood pressure responses to the Trier Social Stress Test. Individuals with high agentic Positive Emotionality exhibited prolonged heart rate responses to stress, whereas those with high communal Positive Emotionality exhibited smaller cortisol and blood pressure responses. Separate personality traits differentially predicted emotional, cardiovascular, and cortisol responses to a psychosocial stressor in healthy volunteers. Future research investigating the association of personality with chronic stress-related disease may provide further clues to the relationship between acute stress reactivity and susceptibility to disease.

  14. Genome-Wide Identification of MicroRNAs in Response to Cadmium Stress in Oilseed Rape (Brassica napus L. Using High-Throughput Sequencing

    Directory of Open Access Journals (Sweden)

    Hongju Jian

    2018-05-01

    Full Text Available MicroRNAs (miRNAs have important roles in regulating stress-response genes in plants. However, identification of miRNAs and the corresponding target genes that are induced in response to cadmium (Cd stress in Brassica napus remains limited. In the current study, we sequenced three small-RNA libraries from B. napus after 0 days, 1 days, and 3 days of Cd treatment. In total, 44 known miRNAs (belonging to 27 families and 103 novel miRNAs were identified. A comprehensive analysis of miRNA expression profiles found 39 differentially expressed miRNAs between control and Cd-treated plants; 13 differentially expressed miRNAs were confirmed by qRT-PCR. Characterization of the corresponding target genes indicated functions in processes including transcription factor regulation, biotic stress response, ion homeostasis, and secondary metabolism. Furthermore, we propose a hypothetical model of the Cd-response mechanism in B. napus. Combined with qRT-PCR confirmation, our data suggested that miRNAs were involved in the regulations of TFs, biotic stress defense, ion homeostasis and secondary metabolism synthesis to respond Cd stress in B. napus.

  15. Genome-wide identification of soybean WRKY transcription factors in response to salt stress.

    Science.gov (United States)

    Yu, Yanchong; Wang, Nan; Hu, Ruibo; Xiang, Fengning

    2016-01-01

    Members of the large family of WRKY transcription factors are involved in a wide range of developmental and physiological processes, most particularly in the plant response to biotic and abiotic stress. Here, an analysis of the soybean genome sequence allowed the identification of the full complement of 188 soybean WRKY genes. Phylogenetic analysis revealed that soybean WRKY genes were classified into three major groups (I, II, III), with the second group further categorized into five subgroups (IIa-IIe). The soybean WRKYs from each group shared similar gene structures and motif compositions. The location of the GmWRKYs was dispersed over all 20 soybean chromosomes. The whole genome duplication appeared to have contributed significantly to the expansion of the family. Expression analysis by RNA-seq indicated that in soybean root, 66 of the genes responded rapidly and transiently to the imposition of salt stress, all but one being up-regulated. While in aerial part, 49 GmWRKYs responded, all but two being down-regulated. RT-qPCR analysis showed that in the whole soybean plant, 66 GmWRKYs exhibited distinct expression patterns in response to salt stress, of which 12 showed no significant change, 35 were decreased, while 19 were induced. The data present here provide critical clues for further functional studies of WRKY gene in soybean salt tolerance.

  16. Genes and co-expression modules common to drought and bacterial stress responses in Arabidopsis and rice.

    Directory of Open Access Journals (Sweden)

    Rafi Shaik

    Full Text Available Plants are simultaneously exposed to multiple stresses resulting in enormous changes in the molecular landscape within the cell. Identification and characterization of the synergistic and antagonistic components of stress response mechanisms contributing to the cross talk between stresses is of high priority to explore and enhance multiple stress responses. To this end, we performed meta-analysis of drought (abiotic, bacterial (biotic stress response in rice and Arabidopsis by analyzing a total of 386 microarray samples belonging to 20 microarray studies and identified approximately 3100 and 900 DEGs in rice and Arabidopsis, respectively. About 38.5% (1214 and 28.7% (272 DEGs were common to drought and bacterial stresses in rice and Arabidopsis, respectively. A majority of these common DEGs showed conserved expression status in both stresses. Gene ontology enrichment analysis clearly demarcated the response and regulation of various plant hormones and related biological processes. Fatty acid metabolism and biosynthesis of alkaloids were upregulated and, nitrogen metabolism and photosynthesis was downregulated in both stress conditions. WRKY transcription family genes were highly enriched in all upregulated gene sets while 'CO-like' TF family showed inverse relationship of expression between drought and bacterial stresses. Weighted gene co-expression network analysis divided DEG sets into multiple modules that show high co-expression and identified stress specific hub genes with high connectivity. Detection of consensus modules based on DEGs common to drought and bacterial stress revealed 9 and 4 modules in rice and Arabidopsis, respectively, with conserved and reversed co-expression patterns.

  17. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

    OpenAIRE

    Dues, Dylan J.; Andrews, Emily K.; Schaar, Claire E.; Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

    2016-01-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxi...

  18. Stress responses in probiotic Lactobacillus casei.

    Science.gov (United States)

    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.

  19. The Role of the Transcriptional Response to DNA Replication Stress.

    Science.gov (United States)

    Herlihy, Anna E; de Bruin, Robertus A M

    2017-03-02

    During DNA replication many factors can result in DNA replication stress. The DNA replication stress checkpoint prevents the accumulation of replication stress-induced DNA damage and the potential ensuing genome instability. A critical role for post-translational modifications, such as phosphorylation, in the replication stress checkpoint response has been well established. However, recent work has revealed an important role for transcription in the cellular response to DNA replication stress. In this review, we will provide an overview of current knowledge of the cellular response to DNA replication stress with a specific focus on the DNA replication stress checkpoint transcriptional response and its role in the prevention of replication stress-induced DNA damage.

  20. The Role of the Transcriptional Response to DNA Replication Stress

    Science.gov (United States)

    Herlihy, Anna E.; de Bruin, Robertus A.M.

    2017-01-01

    During DNA replication many factors can result in DNA replication stress. The DNA replication stress checkpoint prevents the accumulation of replication stress-induced DNA damage and the potential ensuing genome instability. A critical role for post-translational modifications, such as phosphorylation, in the replication stress checkpoint response has been well established. However, recent work has revealed an important role for transcription in the cellular response to DNA replication stress. In this review, we will provide an overview of current knowledge of the cellular response to DNA replication stress with a specific focus on the DNA replication stress checkpoint transcriptional response and its role in the prevention of replication stress-induced DNA damage. PMID:28257104

  1. How age, sex and genotype shape the stress response.

    Science.gov (United States)

    Novais, Ashley; Monteiro, Susana; Roque, Susana; Correia-Neves, Margarida; Sousa, Nuno

    2017-02-01

    Exposure to chronic stress is a leading pre-disposing factor for several neuropsychiatric disorders as it often leads to maladaptive responses. The response to stressful events is heterogeneous, underpinning a wide spectrum of distinct changes amongst stress-exposed individuals'. Several factors can underlie a different perception to stressors and the setting of distinct coping strategies that will lead to individual differences on the susceptibility/resistance to stress. Beyond the factors related to the stressor itself, such as intensity, duration or predictability, there are factors intrinsic to the individuals that are relevant to shape the stress response, such as age, sex and genetics. In this review, we examine the contribution of such intrinsic factors to the modulation of the stress response based on experimental rodent models of response to stress and discuss to what extent that knowledge can be potentially translated to humans.

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

    International Nuclear Information System (INIS)

    Calabrese, Edward J.; Bachmann, Kenneth A.; Bailer, A. John; Bolger, P. Michael; Borak, Jonathan; Cai, Lu; Cedergreen, Nina; Cherian, M. George; Chiueh, Chuang C.; Clarkson, Thomas W.; Cook, Ralph R.; Diamond, David M.; Doolittle, David J.; Dorato, Michael A.; Duke, Stephen O.; Feinendegen, Ludwig; Gardner, Donald E.; Hart, Ronald W.; Hastings, Kenneth L.; Hayes, A. Wallace; Hoffmann, George R.; Ives, John A.; Jaworowski, Zbigniew; Johnson, Thomas E.; Jonas, Wayne B.; Kaminski, Norbert E.; Keller, John G.; Klaunig, James E.; Knudsen, Thomas B.; Kozumbo, Walter J.; Lettieri, Teresa; Liu, Shu-Zheng; Maisseu, Andre; Maynard, Kenneth I.; Masoro, Edward J.; McClellan, Roger O.; Mehendale, Harihara M.; Mothersill, Carmel; Newlin, David B.; Nigg, Herbert N.; Oehme, Frederick W.; Phalen, Robert F.; Philbert, Martin A.; Rattan, Suresh I.S.; Riviere, Jim E.; Rodricks, Joseph; Sapolsky, Robert M.; Scott, Bobby R.; Seymour, Colin; Sinclair, David A.; Smith-Sonneborn, Joan; Snow, Elizabeth T.; Spear, Linda; Stevenson, Donald E.; Thomas, Yolene; Tubiana, Maurice; Williams, Gary M.; Mattson, Mark P.

    2007-01-01

    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

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

    NARCIS (Netherlands)

    Brouwer, S.J.M. de; Kraaimaat, F.W.; Sweep, F.C.; Donders, A.R.T.; Eijsbouts, A.; Koulil, S. van; Riel, P.L.C.M. van; Evers, A.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

  4. Different adaptation strategies of two citrus scion/rootstock combinations in response to drought stress.

    Science.gov (United States)

    Dutra de Souza, Joadson; de Andrade Silva, Edson Mario; Coelho Filho, Mauricio Antônio; Morillon, Raphaël; Bonatto, Diego; Micheli, Fabienne; da Silva Gesteira, Abelmon

    2017-01-01

    Scion/rootstock interaction is important for plant development and for breeding programs. In this context, polyploid rootstocks presented several advantages, mainly in relation to biotic and abiotic stresses. Here we analyzed the response to drought of two different scion/rootstock combinations presenting different polyploidy: the diploid (2x) and autotetraploid (4x) Rangpur lime (Citrus limonia, Osbeck) rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis) scions, named V/2xRL and V/4xRL, respectively. Based on previous gene expression data, we developed an interactomic approach to identify proteins involved in V/2xRL and V/4xRL response to drought. A main interactomic network containing 3,830 nodes and 97,652 edges was built from V/2xRL and V/4xRL data. Exclusive proteins of the V/2xRL and V/4xRL networks (2,056 and 1,001, respectively), as well as common to both networks (773) were identified. Functional clusters were obtained and two models of drought stress response for the V/2xRL and V/4xRL genotypes were designed. Even if the V/2xRL plant implement some tolerance mechanisms, the global plant response to drought was rapid and quickly exhaustive resulting in a general tendency to dehydration avoidance, which presented some advantage in short and strong drought stress conditions, but which, in long terms, does not allow the plant survival. At the contrary, the V/4xRL plants presented a response which strong impacts on development but that present some advantages in case of prolonged drought. Finally, some specific proteins, which presented high centrality on interactomic analysis were identified as good candidates for subsequent functional analysis of citrus genes related to drought response, as well as be good markers of one or another physiological mechanism implemented by the plants.

  5. Different adaptation strategies of two citrus scion/rootstock combinations in response to drought stress.

    Directory of Open Access Journals (Sweden)

    Joadson Dutra de Souza

    Full Text Available Scion/rootstock interaction is important for plant development and for breeding programs. In this context, polyploid rootstocks presented several advantages, mainly in relation to biotic and abiotic stresses. Here we analyzed the response to drought of two different scion/rootstock combinations presenting different polyploidy: the diploid (2x and autotetraploid (4x Rangpur lime (Citrus limonia, Osbeck rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis scions, named V/2xRL and V/4xRL, respectively. Based on previous gene expression data, we developed an interactomic approach to identify proteins involved in V/2xRL and V/4xRL response to drought. A main interactomic network containing 3,830 nodes and 97,652 edges was built from V/2xRL and V/4xRL data. Exclusive proteins of the V/2xRL and V/4xRL networks (2,056 and 1,001, respectively, as well as common to both networks (773 were identified. Functional clusters were obtained and two models of drought stress response for the V/2xRL and V/4xRL genotypes were designed. Even if the V/2xRL plant implement some tolerance mechanisms, the global plant response to drought was rapid and quickly exhaustive resulting in a general tendency to dehydration avoidance, which presented some advantage in short and strong drought stress conditions, but which, in long terms, does not allow the plant survival. At the contrary, the V/4xRL plants presented a response which strong impacts on development but that present some advantages in case of prolonged drought. Finally, some specific proteins, which presented high centrality on interactomic analysis were identified as good candidates for subsequent functional analysis of citrus genes related to drought response, as well as be good markers of one or another physiological mechanism implemented by the plants.

  6. Contribution of the drought tolerance-related Stress-responsive NAC1 transcription factor to resistance of barley to Ramularia leaf spot

    OpenAIRE

    MCGRANN, GRAHAM R D; STEED, ANDREW; BURT, CHRISTOPHER; GODDARD, RACHEL; LACHAUX, CLEA; BANSAL, ANURADHA; CORBITT, MARGARET; GORNIAK, KALINA; NICHOLSON, PAUL; BROWN, JAMES K M

    2014-01-01

    NAC proteins are plant transcription factors that are involved in tolerance to abiotic and biotic stresses, as well as in many developmental processes. Stress-responsive NAC1 (SNAC1) transcription factor is involved in drought tolerance in barley and rice, but has not been shown previously to have a role in disease resistance. Transgenic over-expression of HvSNAC1 in barley cv. Golden Promise reduced the severity of Ramularia leaf spot (RLS), caused by the fungus Ramularia collo-cygni, but ha...

  7. Species as Stressors: Heterospecific Interactions and the Cellular Stress Response under Global Change.

    Science.gov (United States)

    Gunderson, Alex R; King, Emily E; Boyer, Kirsten; Tsukimura, Brian; Stillman, Jonathon H

    2017-07-01

    Anthropogenic global change is predicted to increase the physiological stress of organisms through changes in abiotic conditions such as temperature, pH, and pollution. However, organisms can also experience physiological stress through interactions with other species, especially parasites, predators, and competitors. The stress of species interactions could be an important driver of species' responses to global change as the composition of biological communities change through factors such as distributional and phenological shifts. Interactions between biotic and abiotic stressors could also induce non-linear physiological stress responses under global change. One of the primary means by which organisms deal with physiological stress is through the cellular stress response (CSR), which is broadly the upregulation of a conserved set of genes that facilitate the removal and repair of damaged macromolecules. Here, we present data on behavioral interactions and CSR gene expression for two competing species of intertidal zone porcelain crab (Petrolisthes cinctipes and Petrolisthes manimaculis). We found that P. cinctipes and P. manimaculis engage in more agonistic behaviors when interacting with heterospecifics than conspecifics; however, we found no evidence that heterospecific interactions induced a CSR in these species. In addition to our new data, we review the literature with respect to CSR induction via species interactions, focusing on predator-prey systems and heterospecific competition. We find extensive evidence for predators to induce cellular stress and aspects of the CSR in prey, even in the absence of direct physical contact between species. Effects of heterospecific competition on the CSR have been studied far less, but we do find evidence that agonistic interactions with heterospecifics can induce components of the CSR. Across all published studies, there is clear evidence that species interactions can lead to cellular stress and induction of the CSR

  8. Extraversion and cardiovascular responses to recurrent social stress: Effect of stress intensity.

    Science.gov (United States)

    Lü, Wei; Xing, Wanying; Hughes, Brian M; Wang, Zhenhong

    2017-10-28

    The present study sought to establish whether the effects of extraversion on cardiovascular responses to recurrent social stress are contingent on stress intensity. A 2×5×1 mixed-factorial experiment was conducted, with social stress intensity as a between-subject variable, study phase as a within-subject variable, extraversion as a continuous independent variable, and cardiovascular parameter (HR, SBP, DBP, or RSA) as a dependent variable. Extraversion (NEO-FFI), subjective stress, and physiological stress were measured in 166 undergraduate students randomly assigned to undergo moderate (n=82) or high-intensity (n=84) social stress (a public speaking task with different levels of social evaluation). All participants underwent continuous physiological monitoring while facing two consecutive stress exposures distributed across five laboratory phases: baseline, stress exposure 1, post-stress 1, stress exposure 2, post-stress 2. Results indicated that under moderate-intensity social stress, participants higher on extraversion exhibited lesser HR reactivity to stress than participants lower on extraversion, while under high-intensity social stress, they exhibited greater HR, SBP, DBP and RSA reactivity. Under both moderate- and high-intensity social stress, participants higher on extraversion exhibited pronounced SBP and DBP response adaptation to repeated stress, and showed either better degree of HR recovery or greater amount of SBP and DBP recovery after stress. These findings suggest that individuals higher on extraversion exhibit physiological flexibility to cope with social challenges and benefit from adaptive cardiovascular responses. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response

    Directory of Open Access Journals (Sweden)

    Jos F. Brosschot

    2018-03-01

    Full Text Available Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always “on” but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  10. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response.

    Science.gov (United States)

    Brosschot, Jos F; Verkuil, Bart; Thayer, Julian F

    2018-03-07

    Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always "on" but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS) states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  11. The relationship between beginning teachers' stress causes, stress responses, teaching behaviour and attrition

    NARCIS (Netherlands)

    Harmsen, Ruth; Lorenz, Michelle; Maulana, Ridwan; van Veen, Klaas

    2018-01-01

    In this study, the relationships between beginning teachers’ perceived stress causes, stress responses, observed teaching behaviour and attrition is investigated employing structural equation modelling (SEM). A total of 143 BTs were surveyed using the Questionnaire on the Experience and Evaluation

  12. ROSMETER: a bioinformatic tool for the identification of transcriptomic imprints related to reactive oxygen species type and origin provides new insights into stress responses.

    Science.gov (United States)

    Rosenwasser, Shilo; Fluhr, Robert; Joshi, Janak Raj; Leviatan, Noam; Sela, Noa; Hetzroni, Amotz; Friedman, Haya

    2013-10-01

    The chemical identity of the reactive oxygen species (ROS) and its subcellular origin will leave a specific imprint on the transcriptome response. In order to facilitate the appreciation of ROS signaling, we developed a tool that is tuned to qualify this imprint. Transcriptome data from experiments in Arabidopsis (Arabidopsis thaliana) for which the ROS type and organelle origin are known were compiled into indices and made accessible by a Web-based interface called ROSMETER. The ROSMETER algorithm uses a vector-based algorithm to portray the ROS signature for a given transcriptome. The ROSMETER platform was applied to identify the ROS signatures profiles in transcriptomes of senescing plants and of those exposed to abiotic and biotic stresses. An unexpected highly significant ROS transcriptome signature of mitochondrial stress was detected during the early presymptomatic stages of leaf senescence, which was accompanied by the specific oxidation of mitochondria-targeted redox-sensitive green fluorescent protein probe. The ROSMETER analysis of diverse stresses revealed both commonalties and prominent differences between various abiotic stress conditions, such as salt, cold, ultraviolet light, drought, heat, and pathogens. Interestingly, early responses to the various abiotic stresses clustered together, independent of later responses, and exhibited negative correlations to several ROS indices. In general, the ROS transcriptome signature of abiotic stresses showed limited correlation to a few indices, while biotic stresses showed broad correlation with multiple indices. The ROSMETER platform can assist in formulating hypotheses to delineate the role of ROS in plant acclimation to environmental stress conditions and to elucidate the molecular mechanisms of the oxidative stress response in plants.

  13. Stress

    Science.gov (United States)

    ... can be life-saving. But chronic stress can cause both physical and mental harm. There are at least three different types of stress: Routine stress related to the pressures of work, family, and other daily responsibilities Stress brought about ...

  14. Roots withstanding their environment : Exploiting root system architecture responses to abiotic stress to improve crop tolerance

    NARCIS (Netherlands)

    Koevoets, Iko T; Venema, Jan Henk; Elzenga, J Theo M; Testerink, Christa

    2016-01-01

    To face future challenges in crop production dictated by global climate changes, breeders and plant researchers collaborate to develop productive crops that are able to withstand a wide range of biotic and abiotic stresses. However, crop selection is often focused on shoot performance alone, as

  15. Proteomic analysis of cold stress responses in tobacco seedlings ...

    African Journals Online (AJOL)

    Cold stress is one of the major abiotic stresses limiting the productivity and the geographical distribution of many important crops. To gain a better understanding of cold stress responses in tobacco (Nicotiana tabacum), we carried out a comparative proteomic analysis. Five-week-old tobacco seedlings were treated at 4°C ...

  16. gender and school types as factors responsible for job stress

    African Journals Online (AJOL)

    Emeka Egbochuku

    public Universities should be looked into so that all factors responsible for stress might be .... universities in Malaysia, university academic staffs faced more problems .... adjustment with different coping styles. .... in college students: The role of rumination and stress. ... International Journal of Stress Management, 8, 285–29.

  17. Associations between circadian and stress response cortisol in children.

    Science.gov (United States)

    Simons, Sterre S H; Cillessen, Antonius H N; de Weerth, Carolina

    2017-01-01

    Hypothalamic-pituitary-adrenal (HPA) axis functioning is characterized by the baseline production of cortisol following a circadian rhythm, as well as by the superimposed production of cortisol in response to a stressor. However, it is relatively unknown whether the basal cortisol circadian rhythm is associated with the cortisol stress response in children. Since alterations in cortisol stress responses have been associated with mental and physical health, this study investigated whether the cortisol circadian rhythm is associated with cortisol stress responses in 6-year-old children. To this end, 149 normally developing children (M age  = 6.09 years; 70 girls) participated in an innovative social evaluative stress test that effectively provoked increases in cortisol. To determine the cortisol stress response, six cortisol saliva samples were collected and two cortisol stress response indices were calculated: total stress cortisol and cortisol stress reactivity. To determine children's cortisol circadian rhythm eight cortisol circadian samples were collected during two days. Total diurnal cortisol and diurnal cortisol decline scores were calculated as indices of the cortisol circadian rhythm. Hierarchical regression analyses indicated that higher total diurnal cortisol as well as a smaller diurnal cortisol decline, were both uniquely associated with higher total stress cortisol. No associations were found between the cortisol circadian rhythm indices and cortisol stress reactivity. Possible explanations for the patterns found are links with children's self-regulatory capacities and parenting quality.

  18. Approaches to modeling the development of physiological stress responsivity.

    Science.gov (United States)

    Hinnant, J Benjamin; Philbrook, Lauren E; Erath, Stephen A; El-Sheikh, Mona

    2018-05-01

    Influential biopsychosocial theories have proposed that some developmental periods in the lifespan are potential pivot points or opportunities for recalibration of stress response systems. To date, however, there have been few longitudinal studies of physiological stress responsivity and no studies comparing change in physiological stress responsivity across developmental periods. Our goals were to (a) address conceptual and methodological issues in studying the development of physiological stress responsivity within and between individuals, and (b) provide an exemplar for evaluating development of responsivity to stress in the parasympathetic nervous system, comparing respiratory sinus arrhythmia (RSA) responsivity from middle to late childhood with middle to late adolescence. We propose the use of latent growth modeling of stress responsivity that includes time-varying covariates to account for conceptual and methodological issues in the measurement of physiological stress responsivity. Such models allow researchers to address key aspects of developmental sensitivity including within-individual variability, mean level change over time, and between-individual variability over time. In an empirical example, we found significant between-individual variability over time in RSA responsivity to stress during middle to late childhood but not during middle to late adolescence, suggesting that childhood may be a period of greater developmental sensitivity at the between-individual level. © 2017 Society for Psychophysiological Research.

  19. The stress response system of proteins: Implications for bioreactor scaleup

    Science.gov (United States)

    Goochee, Charles F.

    1988-01-01

    Animal cells face a variety of environmental stresses in large scale bioreactors, including periodic variations in shear stress and dissolved oxygen concentration. Diagnostic techniques were developed for identifying the particular sources of environmental stresses for animal cells in a given bioreactor configuration. The mechanisms by which cells cope with such stresses was examined. The individual concentrations and synthesis rates of hundreds of intracellular proteins are affected by the extracellular environment (medium composition, dissolved oxygen concentration, ph, and level of surface shear stress). Techniques are currently being developed for quantifying the synthesis rates and concentrations of the intracellular proteins which are most sensitive to environmental stress. Previous research has demonstrated that a particular set of stress response proteins are synthesized by mammalian cells in response to temperature fluctuations, dissolved oxygen deprivation, and glucose deprivation. Recently, it was demonstrated that exposure of human kidney cells to high shear stress results in expression of a completely distinct set of intracellular proteins.

  20. Transcriptome-wide identification of bread wheat WRKY transcription factors in response to drought stress.

    Science.gov (United States)

    Okay, Sezer; Derelli, Ebru; Unver, Turgay

    2014-10-01

    The WRKY superfamily of transcription factors was shown to be involved in biotic and abiotic stress responses in plants such as wheat (Triticum aestivum L.), one of the major crops largely cultivated and consumed all over the world. Drought is an important abiotic stress resulting in a considerable amount of loss in agronomical yield. Therefore, identification of drought responsive WRKY members in wheat has a profound significance. Here, a total of 160 TaWRKY proteins were characterized according to sequence similarity, motif varieties, and their phylogenetic relationships. The conserved sequences of the TaWRKYs were aligned and classified into three main groups and five subgroups. A novel motif in wheat, WRKYGQR, was identified. To putatively determine the drought responsive TaWRKY members, publicly available RNA-Seq data were analyzed for the first time in this study. Through in silico searches, 35 transcripts were detected having an identity to ten known TaWRKY genes. Furthermore, relative expression levels of TaWRKY16/TaWRKY16-A, TaWRKY17, TaWRKY19-C, TaWRKY24, TaWRKY59, TaWRKY61, and TaWRKY82 were measured in root and leaf tissues of drought-tolerant Sivas 111/33 and susceptible Atay 85 cultivars. All of the quantified TaWRKY transcripts were found to be up-regulated in root tissue of Sivas 111/33. Differential expression of TaWRKY16, TaWRKY24, TaWRKY59, TaWRKY61 and TaWRKY82 genes was discovered for the first time upon drought stress in wheat. These comprehensive analyses bestow a better understanding about the WRKY TFs in bread wheat under water deficit, and increased number of drought responsive WRKYs would contribute to the molecular breeding of tolerant wheat cultivars.

  1. Adaptive Responses to Thermal Stress in Mammals

    OpenAIRE

    Yasser Lenis Sanin; Angélica María Zuluaga Cabrera; Ariel Marcel Tarazona Morales

    2015-01-01

    The environment animals have to cope with is a combination of natural factors such as temperature. Extreme changes in these factors can alter homeostasis, which can lead to thermal stress. This stress can be due to either high temperatures or low temperatures. Energy transference for thermoregulation in homoeothermic animals occurs through several mechanisms: conduction, convection, radiation and evaporation. When animals are subjected to thermal stress, physiological mechanisms are activated...

  2. Proteomic studies of drought stress response in Fabaceae

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Transcriptome Responses to Combinations of Stresses in Arabidopsis

    DEFF Research Database (Denmark)

    Rasmussen, Simon; Barah, Pankaj; Suarez-Rodriguez, Maria Cristina

    2013-01-01

    In Arabidopsis, the response of the majority of the genes cannot be predicted from single stress experiments and only a small fraction of the genes have potential antagonistic responses, indicating that plants have evolved to cope with combinations of stresses and therefore may be bred to endure...

  5. Salt and drought stress and ABA responses related to bZIP genes from V. radiata and V. angularis.

    Science.gov (United States)

    Wang, Lanfen; Zhu, Jifeng; Li, Xiaoming; Wang, Shumin; Wu, Jing

    2018-04-20

    Mung bean and adzuki bean are warm-season legumes widely cultivated in China. However, bean production in major producing regions is limited by biotic and abiotic stress, such as drought and salt stress. Basic leucine zipper (bZIP) genes play key roles in responses to various biotic and abiotic stresses. However, only several bZIP genes involved in drought and salt stress in legumes, especially Vigna radiata and Vigna angularis, have been identified. In this study, we identified 54 and 50 bZIP proteins from whole-genome sequences of V. radiata and V. angularis, respectively. First, we comprehensively surveyed the characteristics of all bZIP genes, including their gene structure, chromosome distribution and motif composition. Phylogenetic trees showed that VrbZIP and VabZIP proteins were divided into ten clades comprising nine known and one unknown subgroup. The results of the nucleotide substitution rate of the orthologous gene pairs showed that bZIP proteins have undergone strong purifying selection: V. radiata and V. angularis diverged 1.25 million years ago (mya) to 9.20 mya (average of 4.95 mya). We also found that many cis-acting regulatory elements (CAREs) involved in abiotic stress and plant hormone responses were detected in the putative promoter regions of the bZIP genes. Finally, using the quantitative real-time PCR (qRT-PCR) method, we performed expression profiling of the bZIP genes in response to drought, salt and abscisic acid (ABA). We identified several bZIP genes that may be involved in drought and salt responses. Generally, our results provided useful and rich resources of VrbZIP and VabZIP genes for the functional characterization and understanding of bZIP transcription factors (TFs) in warm-season legumes. In addition, our results revealed important and interesting data - a subset of VrbZIP and VabZIP gene expression profiles in response to drought, salt and ABA stress. These results provide gene expression evidence for the selection of

  6. Perceived stress at work is associated with attenuated DHEA-S response during acute psychosocial stress.

    Science.gov (United States)

    Lennartsson, Anna-Karin; Theorell, Töres; Kushnir, Mark M; Bergquist, Jonas; Jonsdottir, Ingibjörg H

    2013-09-01

    Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) have been suggested to play a protective role during acute psychosocial stress, because they act as antagonists to the effects of the stress hormone cortisol. This study aims to investigate whether prolonged psychosocial stress, measured as perceived stress at work during the past week, is related to the capacity to produce DHEA and DHEA-S during acute psychosocial stress. It also aims to investigate whether prolonged perceived stress affects the balance between production of cortisol and DHEA-S during acute psychosocial stress. Thirty-six healthy subjects (19 men and 17 women, mean age 37 years, SD 5 years), were included. Perceived stress at work during the past week was measured by using the Stress-Energy (SE) Questionnaire. The participants were divided into three groups based on their mean scores; Low stress, Medium stress and High stress. The participants underwent the Trier Social Stress Test (TSST) and blood samples were collected before, directly after the stress test, and after 30 min of recovery. General Linear Models were used to investigate if the Medium stress group and the High stress group differ regarding stress response compared to the Low stress group. Higher perceived stress at work was associated with attenuated DHEA-S response during acute psychosocial stress. Furthermore, the ratio between the cortisol production and the DHEA-S production during the acute stress test were higher in individuals reporting higher perceived stress at work compared to individuals reporting low perceived stress at work. There was no statistical difference in DHEA response between the groups. This study shows that prolonged stress, measured as perceived stress at work during the past week, seems to negatively affect the capacity to produce DHEA-S during acute stress. Given the protective functions of DHEA-S, attenuated DHEA-S production during acute stress may lead to higher risk for adverse

  7. The temporal dynamics of the stress response

    NARCIS (Netherlands)

    Koolhaas, J.M.; Meerlo, P; de Boer, S.F.; Strubbe, J.H.; Bohus, B.G J

    1997-01-01

    This paper summarises the available evidence that failure of defense mechanisms in (semi)-natural social groups of animals may lead to serious forms of stress pathology. Hence the study of social stress may provide animal models with a high face validity. However, most of the animal models of human

  8. Psychological and hormonal stress response patterns during a blood donation.

    Science.gov (United States)

    Hoogerwerf, M D; Veldhuizen, I J T; Merz, E-M; de Kort, W L A M; Frings-Dresen, M H W; Sluiter, J K

    2017-11-01

    Donating blood has been associated with increased stress responses, with scarce evidence indicating that levels of psychological and hormonal stress are higher pre-donation than post-donation. We investigated whether a blood donation induces psychological and/or hormonal stress during the course of a blood donation, and whether responses differed between men and women, first-time and experienced donors and donors with high or low non-acute stress. In 363 donors, psychological (donation-stress and arousal) and hormonal (cortisol) stress were measured by questionnaire and salivary sample at seven key moments during a routine donation. Non-acute stress was assessed by a questionnaire. Repeated measurement analyses were performed, using the last measurement (leaving the donation center) as reference value. Levels of donation-stress, arousal and cortisol were significantly higher during donation than when leaving the donation center. When compared with men, women reported higher levels of donation-stress and cortisol in the first part of the visit. When compared with first-time donors, experienced donors reported lower levels of donation-stress during the first part of the visit, and higher levels of arousal but less reactivity throughout the visit. When compared to donors high on non-acute stress, donors low on non-acute stress reported lower levels of donation-stress during the first part of the visit, and showed less cortisol reactivity throughout the visit. Donating blood influences psychological and hormonal stress response patterns. The response patterns differ between women and men, first-time and experienced donors and between donors high and low on non-acute stress. © 2017 International Society of Blood Transfusion.

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

    KAUST Repository

    Kawa, Dorota; Julkowska, Magdalena; Montero Sommerfeld, Hector; Horst, Anneliek ter; Haring, Michel A; Testerink, Christa

    2016-01-01

    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.

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

    KAUST Repository

    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.

  11. Response inhibition and cognitive appraisal in clients with acute stress disorder and posttraumatic stress disorder.

    Science.gov (United States)

    Abolghasemi, Abass; Bakhshian, Fereshteh; Narimani, Mohammad

    2013-08-01

    The purpose of the present study was to compare response inhibition and cognitive appraisal in clients with acute stress disorder, clients with posttraumatic stress disorder, and normal individuals. This was a comparative study. The sample consisted of 40 clients with acute stress disorder, 40 patients with posttraumatic stress disorder, and 40 normal individuals from Mazandaran province selected through convenience sampling method. Data were collected using Composite International Diagnostic Interview, Stroop Color-Word Test, Posttraumatic Cognitions Inventory, and the Impact of Event Scale. Results showed that individuals with acute stress disorder are less able to inhibit inappropriate responses and have more impaired cognitive appraisals compared to those with posttraumatic stress disorder. Moreover, results showed that response inhibition and cognitive appraisal explain 75% of the variance in posttraumatic stress disorder symptoms and 38% of the variance in posttraumatic stress disorder symptoms. The findings suggest that response inhibition and cognitive appraisal are two variables that influence the severity of posttraumatic stress disorder and acute stress disorder symptoms. Also, these results have important implications for pathology, prevention, and treatment of posttraumatic stress disorder and acute stress disorder.

  12. Response Inhibition and Cognitive Appraisal in Clients with Acute Stress Disorder and Posttraumatic Stress Disorder

    Directory of Open Access Journals (Sweden)

    Abass Abolghasemi

    2013-09-01

    Full Text Available Objective: The purpose of the present study was to compare response inhibition and cognitive appraisal in clients with acute stress disorder, clients with posttraumatic stress disorder, and normal individuals .Method:This was a comparative study. The sample consisted of 40 clients with acute stress disorder, 40 patients with posttraumatic stress disorder, and 40 normal individuals from Mazandaran province selected through convenience sampling method. Data were collected using Composite International Diagnostic Interview, Stroop Color-Word Test, Posttraumatic Cognitions Inventory, and the Impact of Event Scale. Results:Results showed that individuals with acute stress disorder are less able to inhibit inappropriate responses and have more impaired cognitive appraisals compared to those with posttraumatic stress disorder. Moreover, results showed that response inhibition and cognitive appraisal explain 75% of the variance in posttraumatic stress disorder symptoms and 38% of the variance in posttraumatic stress disorder symptoms .Conclusion:The findings suggest that response inhibition and cognitive appraisal are two variables that influence the severity of posttraumatic stress disorder and acute stress disorder symptoms. Also, these results have important implications for pathology, prevention, and treatment of posttraumatic stress disorder and acute stress disorder

  13. Transcriptional 'memory' of a stress: transient chromatin and memory (epigenetic) marks at stress-response genes.

    Science.gov (United States)

    Avramova, Zoya

    2015-07-01

    Drought, salinity, extreme temperature variations, pathogen and herbivory attacks are recurring environmental stresses experienced by plants throughout their life. To survive repeated stresses, plants provide responses that may be different from their response during the first encounter with the stress. A different response to a similar stress represents the concept of 'stress memory'. A coordinated reaction at the organismal, cellular and gene/genome levels is thought to increase survival chances by improving the plant's tolerance/avoidance abilities. Ultimately, stress memory may provide a mechanism for acclimation and adaptation. At the molecular level, the concept of stress memory indicates that the mechanisms responsible for memory-type transcription during repeated stresses are not based on repetitive activation of the same response pathways activated by the first stress. Some recent advances in the search for transcription 'memory factors' are discussed with an emphasis on super-induced dehydration stress memory response genes in Arabidopsis. © 2015 The Author The Plant Journal © 2015 John Wiley & Sons Ltd.

  14. Stretching the Stress Boundary: Linking Air Pollution Health Effects to a Neurohormonal Stress Response

    Science.gov (United States)

    Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer’s and diabetes. A neurohormonal stress response (referred here as a systemic response produced by activation ...

  15. Response of rocks to large stresses

    International Nuclear Information System (INIS)

    Schock, R.N.

    1976-01-01

    To predict the dimensions and characteristics of impact- and explosion-induced craters, one must know the equation of state of the rocks in which the crater is formed. Recent experimental data shed light upon inelastic processes that influence the stress/strain behavior of rocks. We examine these data with a view to developing models that could be used in predicting cratering phenomena. New data is presented on the volume behavior of two dissimilar rocks subjected to tensile stresses

  16. The significance of translation regulation in the stress response

    OpenAIRE

    Picard, Flora; Loubière, Pascal; Girbal, Laurence; Bousquet, Muriel

    2013-01-01

    Background: The stress response in bacteria involves the multistage control of gene expression but is not entirely understood. To identify the translational response of bacteria in stress conditions and assess its contribution to the regulation of gene expression, the translational states of all mRNAs were compared under optimal growth condition and during nutrient (isoleucine) starvation. Results: A genome-scale study of the translational response to nutritional limitation was performed in t...

  17. Associations between circadian and stress response cortisol in children

    OpenAIRE

    Simons, S.S.H.; Cillessen, A.H.N.; Weerth, C. de

    2017-01-01

    Hypothalamic-pituitary-adrenal (HPA) axis functioning is characterized by the baseline production of cortisol following a circadian rhythm, as well as by the superimposed production of cortisol in response to a stressor. However, it is relatively unknown whether the basal cortisol circadian rhythm is associated with the cortisol stress response in children. Since alterations in cortisol stress responses have been associated with mental and physical health, this study investigated whether the ...

  18. Predictors of responses to stress among families coping with poverty-related stress.

    Science.gov (United States)

    Santiago, Catherine DeCarlo; Etter, Erica Moran; Wadsworth, Martha E; Raviv, Tali

    2012-05-01

    This study tested how poverty-related stress (PRS), psychological distress, and responses to stress predicted future effortful coping and involuntary stress responses one year later. In addition, we explored age, sex, ethnicity, and parental influences on responses to stress over time. Hierarchical linear modeling analyses conducted with 98 low-income families (300 family members: 136 adults, 82 school-aged children, 82 adolescents) revealed that primary control coping, secondary control coping, disengagement, involuntary engagement, and involuntary disengagement each significantly predicted future use of that response. Primary and secondary control coping also predicted less maladaptive future responses to stress, while involuntary responses to stress undermined the development of adaptive responding. Age, sex, and interactions among PRS and prior coping were also found to predict certain responses to stress. In addition, child subgroup analyses demonstrate the importance of parental modeling of coping and involuntary stress responses, and warmth/nurturance and monitoring practices. Results are discussed with regard to the implications for preventive interventions with families in poverty.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    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...

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Triticale biotic stresses--an overview.

    Science.gov (United States)

    Arseniuk, Edward

    2014-01-01

    Triticale has been considered as resistant to diseases over a long time. Although, many authors perpetuate this opinion, it is no longer true. However, in comparison to wheat and rye triticale still may look as a healthy crop, but its healthiness has been steadily declining. It could be explained by steady expansion of the growing area and longer exposure to pathogens. On the other hand, triticale is a crop on which meet pathogens of wheat and rye, but there is evidence that on triticale embedded more so called "wheat pathogens", than rye ones. For such an notable example may serve races of Puccinia recondita. In the latter respect triticale also appears to be a bridge facilitating a direct contact between the pathogens, e.g. between physiological forms of the most important cereal rusts. Such contacts stimulate somatic hybridization on bridging triticale plant and may finally result in new hybrid pathotypes carrying virulence genes (factors) to all three hosts, i.e. triticale, wheat and rye. In addition to all triticale commercial and agronomical values, triticale still is and it will continue to be bridging transfers of resistance genes to various pathogens and pests mainly from rye to wheat. The paper will describe main diseases affecting triticale worldwide. The first disease which occurred on this cereal in epidemic proportions was stem rust (Pucinia graminis f. sp. tritici) in Australia. Leaf and stripe rusts (P. recondita f. sp. tritici and P. striiformis) are also have gained in importance everywhere triticale is grown. In recent years, at least in Poland, powdery mildew caused by Blumeria graminis occurred in epidemic proportions in quite a number of winter triticale cultivars. Similar phenomenon has been observed with quite a number of other diseases caused by facultative pathogens, such as the most damaging to triticale the Stagonospora spp. leaf and glume blotch disease complex and other pathogens like Cochliobolus sativus, Fusarium culmorum, and F. graminearum, Microdochium nivale, Bipolaris sorokiniana, Pseudocercosporella herpotrichoides, and Gaeumannomyces gramminis var. tritici inciting head, leaf and seedling blights and foot, crown and root rots. Diseases caused by bacteria, viruses, virus-like organisms and nematodes are also duly treated in this overview.

  2. Cloning and Expression Analysis of an AP2/ERF Gene and Its Responses to Phytohormones and Abiotic Stresses in Rice

    Directory of Open Access Journals (Sweden)

    Hao-li MA

    2010-03-01

    Full Text Available Ethylene response factors (ERFs play important roles in response to plant biotic and abiotic stresses. In this study, a gene encoding a putative AP2/ERF domain-containing protein was isolated by screening a SSH cDNA library from rice and designated as Oryza sativa AP2/ERF-like protein (OsAP2LP gene. OsAP2LP is 1491 bp in length, interrupted by seven introns, and encodes a putative protein of 348 amino acids. Temporal and spatial expression analysis showed that the OsAP2LP gene was preferentially expressed in roots, panicles, mature embryos and seeds in rice. Real-time quantitative PCR analysis indicated that the expression levels of the OsAP2LP gene were increased under the treatments of drought and gibberellin but decreased under the treatments of low temperature, salt, abscisic acid (ABA and zeatin. Taken together, these results suggest that OsAP2LP might be involved in stress responses, and probably plays roles as a transcription regulator when plants response to cold, salt and drought stresses through ABA and gibberellin pathways.

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

    Science.gov (United States)

    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…

  4. Oxidative stress response after laparoscopic versus conventional sigmoid resection

    DEFF Research Database (Denmark)

    Madsen, Michael Tvilling; Kücükakin, Bülent; Lykkesfeldt, Jens

    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...... 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......, 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...

  5. Plant transcriptomics and responses to environmental stress

    Indian Academy of Sciences (India)

    Atta-ur-Rehman School of Applied Biosciences, National University of Sciences and Technology, H-12 Campus, Islamabad 25000, Pakistan; Stress Physiology Lab Department of Botany, Jiwaji University, Gwalior 474 011, India; Centre for Environmental Research, Near East University, 33010, Lefkosha, Turkish Republic ...

  6. Friend or foe? Reactive oxygen species production, scavenging and signaling in plant response to environmental stresses.

    Science.gov (United States)

    Czarnocka, Weronika; Karpiński, Stanisław

    2018-01-10

    In the natural environment, plants are exposed to a variety of biotic and abiotic stress conditions that trigger rapid changes in the production and scavenging of reactive oxygen species (ROS). The production and scavenging of ROS is compartmentalized, which means that, depending on stimuli type, they can be generated and eliminated in different cellular compartments such as the apoplast, plasma membrane, chloroplasts, mitochondria, peroxisomes, and endoplasmic reticulum. Although the accumulation of ROS is generally harmful to cells, ROS play an important role in signaling pathways that regulate acclimatory and defense responses in plants, such as systemic acquired acclimation (SAA) and systemic acquired resistance (SAR). However, high accumulations of ROS can also trigger redox homeostasis disturbance which can lead to cell death, and in consequence, to a limitation in biomass and yield production. Different ROS have various half-lifetimes and degrees of reactivity toward molecular components such as lipids, proteins, and nucleic acids. Thus, they play different roles in intra- and extra-cellular signaling. Despite their possible damaging effect, ROS should mainly be considered as signaling molecules that regulate local and systemic acclimatory and defense responses. Over the past two decades it has been proven that ROS together with non-photochemical quenching (NPQ), hormones, Ca 2+ waves, and electrical signals are the main players in SAA and SAR, two physiological processes essential for plant survival and productivity in unfavorable conditions. Copyright © 2018. Published by Elsevier Inc.

  7. The relationship between personality and the response to acute psychological stress

    NARCIS (Netherlands)

    Xin, Yuanyuan; Wu, Jianhui; Yao, Zhuxi; Guan, Qing; Aleman, Andre; Luo, Yuejia

    2017-01-01

    The present study examined the relationship between personality traits and the response to acute psychological stress induced by a standardized laboratory stress induction procedure (the Trier Social Stress Test, TSST). The stress response was measured with a combination of cardiovascular

  8. Cell Wall Metabolism in Response to Abiotic Stress

    Science.gov (United States)

    Gall, Hyacinthe Le; Philippe, Florian; Domon, Jean-Marc; Gillet, Françoise; Pelloux, Jérôme; Rayon, Catherine

    2015-01-01

    This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions. PMID:27135320

  9. Cellular stress responses for monitoring and modulating ageing

    DEFF Research Database (Denmark)

    Demirovic, Dino; Schnebert, Sylvianne; Nizard, Carine

    2013-01-01

    biochemical methods, detecting one or more proteins exclusively involved in the specific stress response pathways. The results indicate that the ageing phenotype is a result of an ineffective probability for cells to respond to stress. http://dx.doi.org/10.1016/j.freeradbiomed.2013.08.023...

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

    Science.gov (United States)

    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…

  11. Psychological and hormonal stress response patterns during a blood donation

    NARCIS (Netherlands)

    Hoogerwerf, M. D.; Veldhuizen, I. J. T.; Merz, E.-M.; de Kort, W. L. A. M.; Frings-Dresen, M. H. W.; Sluiter, J. K.

    2017-01-01

    Background and ObjectivesDonating blood has been associated with increased stress responses, with scarce evidence indicating that levels of psychological and hormonal stress are higher pre-donation than post-donation. We investigated whether a blood donation induces psychological and/or hormonal

  12. Differentiating anticipatory from reactive cortisol responses to psychosocial stress

    NARCIS (Netherlands)

    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

  13. Plant responsiveness to root-root communication of stress cues.

    Science.gov (United States)

    Falik, Omer; Mordoch, Yonat; Ben-Natan, Daniel; Vanunu, Miriam; Goldstein, Oron; Novoplansky, Ariel

    2012-07-01

    Phenotypic plasticity is based on the organism's ability to perceive, integrate and respond to multiple signals and cues informative of environmental opportunities and perils. A growing body of evidence demonstrates that plants are able to adapt to imminent threats by perceiving cues emitted from their damaged neighbours. Here, the hypothesis was tested that unstressed plants are able to perceive and respond to stress cues emitted from their drought- and osmotically stressed neighbours and to induce stress responses in additional unstressed plants. Split-root Pisum sativum, Cynodon dactylon, Digitaria sanguinalis and Stenotaphrum secundatum plants were subjected to osmotic stress or drought while sharing one of their rooting volumes with an unstressed neighbour, which in turn shared its other rooting volume with additional unstressed neighbours. Following the kinetics of stomatal aperture allowed testing for stress responses in both the stressed plants and their unstressed neighbours. In both P. sativum plants and the three wild clonal grasses, infliction of osmotic stress or drought caused stomatal closure in both the stressed plants and in their unstressed neighbours. While both continuous osmotic stress and drought induced prolonged stomatal closure and limited acclimation in stressed plants, their unstressed neighbours habituated to the stress cues and opened their stomata 3-24 h after the beginning of stress induction. The results demonstrate a novel type of plant communication, by which plants might be able to increase their readiness to probable future osmotic and drought stresses. Further work is underway to decipher the identity and mode of operation of the involved communication vectors and to assess the potential ecological costs and benefits of emitting and perceiving drought and osmotic stress cues under various ecological scenarios.

  14. Proceedings of DAE-BRNS life sciences symposium 2011 on advances in molecular and cell biology of stress response

    International Nuclear Information System (INIS)

    2011-01-01

    is being elucidated. Chromatin remodelling is another emerging area in the context of differential gene expression following exposure to stressors in plants as well as mammalian systems. Its role in the development of functional dichotomy in helper T cells has been recently established. It will be interesting to look at changes in the methylation or acetylation of histones following continuous low level radiation exposure. Bacteria have provided intriguing model systems to investigate stress response, Deinococcus radiodurans being a challenging example. In plants the intensive basic research effort may provide mechanistic answers to the efficacy of biotic and abiotic stress tolerant varieties of crop plants that are or will be developed through plant breeding techniques. This symposium will bring together several leading lights in the field of molecular and cell biology of response to stress in different living organisms. Papers relevant to INIS are indexed separately

  15. Psychological distress, cortisol stress response and subclinical coronary calcification

    NARCIS (Netherlands)

    Seldenrijk, A.; Hamer, M.; Lahiri, A.; Penninx, B.W.J.H.; Steptoe, A.

    2012-01-01

    Objectives: Poor mental health has been associated with coronary heart disease (CHD). One hypothesized underlying mechanism is hypothalamus pituitary adrenal axis dysfunction. We examined the associations between psychological distress, cortisol response to laboratory-induced mental stress and

  16. Plant natriuretic peptides are apoplastic and paracrine stress response molecules

    KAUST Repository

    Wang, Yuhua; Gehring, Christoph A; Irving, Helen R.

    2011-01-01

    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.

  17. Stress responses during ageing: molecular pathways regulating protein homeostasis.

    Science.gov (United States)

    Kyriakakis, Emmanouil; Princz, Andrea; Tavernarakis, Nektarios

    2015-01-01

    The ageing process is characterized by deterioration of physiological function accompanied by frailty and ageing-associated diseases. The most broadly and well-studied pathways influencing ageing are the insulin/insulin-like growth factor 1 signaling pathway and the dietary restriction pathway. Recent studies in diverse organisms have also delineated emerging pathways, which collectively or independently contribute to ageing. Among them the proteostatic-stress-response networks, inextricably affect normal ageing by maintaining or restoring protein homeostasis to preserve proper cellular and organismal function. In this chapter, we survey the involvement of heat stress and endoplasmic reticulum stress responses in the regulation of longevity, placing emphasis on the cross talk between different response mechanisms and their systemic effects. We further discuss novel insights relevant to the molecular pathways mediating these stress responses that may facilitate the development of innovative interventions targeting age-related pathologies such as diabetes, cancer, cardiovascular and neurodegenerative diseases.

  18. Herboxidiene triggers splicing repression and abiotic stress responses in plants

    KAUST Repository

    Alshareef, Sahar; Ling, Yu; Butt, Haroon; Mariappan, Kiruthiga G.; Benhamed, Moussa; Mahfouz, Magdy M.

    2017-01-01

    Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and stresses. Small

  19. ABA signaling in stress-response and seed development.

    Science.gov (United States)

    Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2013-07-01

    KEY MESSAGE : We review the recent progress on ABA signaling, especially ABA signaling for ABA-dependent gene expression, including the AREB/ABF regulon, SnRK2 protein kinase, 2C-type protein phosphatases and ABA receptors. Drought negatively impacts plant growth and the productivity of crops. Drought causes osmotic stress to organisms, and the osmotic stress causes dehydration in plant cells. Abscisic acid (ABA) is produced under osmotic stress conditions, and it plays an important role in the stress response and tolerance of plants. ABA regulates many genes under osmotic stress conditions. It also regulates gene expression during seed development and germination. The ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. ABRE-binding protein (AREB)/ABRE-binding factor (ABF) transcription factors (TFs) regulate ABRE-dependent gene expression. Other TFs are also involved in ABA-responsive gene expression. SNF1-related protein kinases 2 are the key regulators of ABA signaling including the AREB/ABF regulon. Recently, ABA receptors and group A 2C-type protein phosphatases were shown to govern the ABA signaling pathway. Moreover, recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress-response and seed development. The control of the expression of ABA signaling factors may improve tolerance to environmental stresses.

  20. Plant Responses to Abiotic Stress Regulated by Histone Deacetylases

    Directory of Open Access Journals (Sweden)

    Ming Luo

    2017-12-01

    Full Text Available In eukaryotic cells, histone acetylation and deacetylation play an important role in the regulation of gene expression. Histone acetylation levels are modulated by histone acetyltransferases and histone deacetylases (HDACs. Recent studies indicate that HDACs play essential roles in the regulation of gene expression in plant response to environmental stress. In this review, we discussed the recent advance regarding the plant HDACs and their functions in the regulation of abiotic stress responses. The role of HDACs in autophagy was also discussed.

  1. Stress Response and Artemisinin Resistance in Malaria Parasite

    Science.gov (United States)

    2017-07-01

    AWARD NUMBER: W81XWH-16-1-0241 TITLE: Stress Response and Artemisinin Resistance in Malaria Parasite PRINCIPAL INVESTIGATOR: Juan C. Pizarro...SUBTITLE Stress Response and Artemisinin Resistance in Malaria Parasite 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-16-1-0241 5c. PROGRAM ELEMENT...13. SUPPLEMENTARY NOTES 14. ABSTRACT In malaria , drug resistance is a major treat to disease control efforts. Unfortunately, there is a significant

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

    Science.gov (United States)

    Henderson, Roselinde K; Snyder, Hannah R; Gupta, Tina; Banich, Marie T

    2012-01-01

    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. 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 showed the greatest Stroop

  3. Context and strain-dependent behavioral response to stress

    Directory of Open Access Journals (Sweden)

    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.

  4. Responses to Fiscal Stress: A Comparative Analysis

    Science.gov (United States)

    2013-12-01

    of “a significant decline in market share by the middle of the 20th century as travelers and shippers turned increasingly to airlines, trucks, and...1995). Intercity passenger rail: Financial and operating conditions threaten Amtrak’s long-term viability (GAO-95-71). Washington, DC: U.S...I. (1980). Retrenchment and flexibility in public organizations. Fiscal Stress and Public Policy, 159–178. Scheinberg, P. F. (1998). Intercity

  5. Stress and Bronchodilator Response in Children with Asthma.

    Science.gov (United States)

    Brehm, John M; Ramratnam, Sima K; Tse, Sze Man; Croteau-Chonka, Damien C; Pino-Yanes, Maria; Rosas-Salazar, Christian; Litonjua, Augusto A; Raby, Benjamin A; Boutaoui, Nadia; Han, Yueh-Ying; Chen, Wei; Forno, Erick; Marsland, Anna L; Nugent, Nicole R; Eng, Celeste; Colón-Semidey, Angel; Alvarez, María; Acosta-Pérez, Edna; Spear, Melissa L; Martinez, Fernando D; Avila, Lydiana; Weiss, Scott T; Soto-Quiros, Manuel; Ober, Carole; Nicolae, Dan L; Barnes, Kathleen C; Lemanske, Robert F; Strunk, Robert C; Liu, Andrew; London, Stephanie J; Gilliland, Frank; Sleiman, Patrick; March, Michael; Hakonarson, Hakon; Duan, Qing Ling; Kolls, Jay K; Fritz, Gregory K; Hu, Donglei; Fani, Negar; Stevens, Jennifer S; Almli, Lynn M; Burchard, Esteban G; Shin, Jaemin; McQuaid, Elizabeth L; Ressler, Kerry; Canino, Glorisa; Celedón, Juan C

    2015-07-01

    Stress is associated with asthma morbidity in Puerto Ricans (PRs), who have reduced bronchodilator response (BDR). To examine whether stress and/or a gene regulating anxiety (ADCYAP1R1) is associated with BDR in PR and non-PR children with asthma. This was a cross-sectional study of stress and BDR (percent change in FEV1 after BD) in 234 PRs ages 9-14 years with asthma. We assessed child stress using the Checklist of Children's Distress Symptoms, and maternal stress using the Perceived Stress Scale. Replication analyses were conducted in two cohorts. Polymorphisms in ADCYAP1R1 were genotyped in our study and six replication studies. Multivariable models of stress and BDR were adjusted for age, sex, income, environmental tobacco smoke, and use of inhaled corticosteroids. High child stress was associated with reduced BDR in three cohorts. PR children who were highly stressed (upper quartile, Checklist of Children's Distress Symptoms) and whose mothers had high stress (upper quartile, Perceived Stress Scale) had a BDR that was 10.2% (95% confidence interval, 6.1-14.2%) lower than children who had neither high stress nor a highly stressed mother. A polymorphism in ADCYAP1R1 (rs34548976) was associated with reduced BDR. This single-nucleotide polymorphism is associated with reduced expression of the gene for the β2-adrenergic receptor (ADRB2) in CD4(+) lymphocytes of subjects with asthma, and it affects brain connectivity of the amygdala and the insula (a biomarker of anxiety). High child stress and an ADCYAP1R1 single-nucleotide polymorphism are associated with reduced BDR in children with asthma. This is likely caused by down-regulation of ADRB2 in highly stressed children.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Linking stress with macroscopic and microscopic leaf response in trees: New diagnostic perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Guenthardt-Goerg, Madeleine S. [Swiss Federal Institute for Forest, Snow and Landscape Research, WSL, Zuercherstrasse 111, CH-8903 Birmensdorf (Switzerland)]. E-mail: madeleine.goerg@wsl.ch; Vollenweider, Pierre [Swiss Federal Institute for Forest, Snow and Landscape Research, WSL, Zuercherstrasse 111, CH-8903 Birmensdorf (Switzerland)

    2007-06-15

    Visible symptoms in tree foliage can be used for stress diagnosis once validated with microscopical analyses. This paper reviews and illustrates macroscopical and microscopical markers of stress with a biotic (bacteria, fungi, insects) or abiotic (frost, drought, mineral deficiency, heavy metal pollution in the soil, acidic deposition and ozone) origin helpful for the validation of symptoms in broadleaved and conifer trees. Differentiation of changes in the leaf or needle physiology, through ageing, senescence, accelerated cell senescence, programmed cell death and oxidative stress, provides additional clues raising diagnosis efficiency, especially in combination with information about the target of the stress agent at the tree, leaf/needle, tissue, cell and ultrastructural level. Given the increasing stress in a changing environment, this review discusses how integrated diagnostic approaches lead to better causal analysis to be applied for specific monitoring of stress factors affecting forest ecosystems. - Macroscopic leaf symptoms and their microscopic analysis as stress bioindications.

  8. Linking stress with macroscopic and microscopic leaf response in trees: New diagnostic perspectives

    International Nuclear Information System (INIS)

    Guenthardt-Goerg, Madeleine S.; Vollenweider, Pierre

    2007-01-01

    Visible symptoms in tree foliage can be used for stress diagnosis once validated with microscopical analyses. This paper reviews and illustrates macroscopical and microscopical markers of stress with a biotic (bacteria, fungi, insects) or abiotic (frost, drought, mineral deficiency, heavy metal pollution in the soil, acidic deposition and ozone) origin helpful for the validation of symptoms in broadleaved and conifer trees. Differentiation of changes in the leaf or needle physiology, through ageing, senescence, accelerated cell senescence, programmed cell death and oxidative stress, provides additional clues raising diagnosis efficiency, especially in combination with information about the target of the stress agent at the tree, leaf/needle, tissue, cell and ultrastructural level. Given the increasing stress in a changing environment, this review discusses how integrated diagnostic approaches lead to better causal analysis to be applied for specific monitoring of stress factors affecting forest ecosystems. - Macroscopic leaf symptoms and their microscopic analysis as stress bioindications

  9. Respective contribution of CML8 and CML9, two arabidopsis calmodulin-like proteins, to plant stress responses.

    Science.gov (United States)

    Zhu, Xiaoyang; Perez, Manon; Aldon, Didier; Galaud, Jean-Philippe

    2017-05-04

    In their natural environment, plants have to continuously face constraints such as biotic and abiotic stresses. To achieve their life cycle, plants have to perceive and interpret the nature, but also the strength of environmental stimuli to activate appropriate physiological responses. Nowadays, it is well established that signaling pathways are crucial steps in the implementation of rapid and efficient plant responses such as genetic reprogramming. It is also reported that rapid raises in calcium (Ca 2+ ) levels within plant cells participate in these early signaling steps and are essential to coordinate adaptive responses. However, to be informative, calcium increases need to be decoded and relayed by calcium-binding proteins also referred as calcium sensors to carry-out the appropriate responses. In a recent study, we showed that CML8, an Arabidopsis calcium sensor belonging to the calmodulin-like (CML) protein family, promotes plant immunity against the phytopathogenic bacteria Pseudomonas syringae pv tomato (strain DC3000). Interestingly, other CML proteins such as CML9 were also reported to contribute to plant immunity using the same pathosystem. In this addendum, we propose to discuss about the specific contribution of these 2 CMLs in stress responses.

  10. Assessing Sources of Stress to Aquatic Ecosystems: Using Biomarkers and Bioindicators to Characterize Exodure-Response Profiles of Anthropogenic Activities

    Energy Technology Data Exchange (ETDEWEB)

    Adams, S.M.

    1999-03-29

    Establishing causal relationships between sources of environmental stressors and aquatic ecosystem health if difficult because of the many biotic and abiotic factors which can influence or modify responses of biological systems to stress, the orders of magnitude involved in extrapolation over both spatial and temporal scales, and compensatory mechanisms such as density-dependent responses that operate in populations. To address the problem of establishing causality between stressors and effects on aquatic systems, a diagnostic approach, based on exposure-response profiles for various anthropogenic activities, was developed to help identify sources of stress responsible for effects on aquatic systems at ecological significant levels of biological organization (individual, population, community). To generate these exposure-effects profiles, biomarkers of exposure were plotted against bioindicators of corresponding effects for several major anthropogenic activities including petrochemical , pulp and paper, domestic sewage, mining operations, land-development activities, and agricultural activities. Biomarkers of exposure to environmental stressors varied depending on the type of anthropogenic activity involved. Bioindicator effects, however, including histopathological lesions, bioenergetic status, individual growth, reproductive impairment, and community-level responses were similar among many of the major anthropogenic activities. This approach is valuable to help identify and diagnose sources of stressors in environments impacted by multiple stressors. By identifying the types and sources of environmental stressors, aquatic ecosystems can be more effectively protected and managed to maintain acceptable levels of environmental quality and ecosystem fitness.

  11. Heart rate variability response to mental arithmetic stress in patients with schizophrenia Autonomic response to stress in schizophrenia

    NARCIS (Netherlands)

    Castro, Mariana N.; Vigo, Daniel E.; Weidema, Hylke; Fahrer, Rodolfo D.; Chu, Elvina M.; De Achaval, Delfina; Nogues, Martin; Leiguarda, Ramon C.; Cardinali, Daniel P.; Guinjoan, Salvador N.

    Background: The vulnerability-stress hypothesis is an established model of schizophrenia symptom formation. We sought to characterise the pattern of the cardiac autonomic response to mental arithmetic stress in patients with stable schizophrenia. Methods: We performed heart rate variability (HRV)

  12. Transcriptome profiling of low temperature-treated cassava apical shoots showed dynamic responses of tropical plant to cold stress

    Directory of Open Access Journals (Sweden)

    An Dong

    2012-02-01

    Full Text Available Abstract Background Cassava is an important tropical root crop adapted to a wide range of environmental stimuli such as drought and acid soils. Nevertheless, it is an extremely cold-sensitive tropical species. Thus far, there is limited information about gene regulation and signalling pathways related to the cold stress response in cassava. The development of microarray technology has accelerated the study of global transcription profiling under certain conditions. Results A 60-mer oligonucleotide microarray representing 20,840 genes was used to perform transcriptome profiling in apical shoots of cassava subjected to cold at 7°C for 0, 4 and 9 h. A total of 508 transcripts were identified as early cold-responsive genes in which 319 sequences had functional descriptions when aligned with Arabidopsis proteins. Gene ontology annotation analysis identified many cold-relevant categories, including 'Response to abiotic and biotic stimulus', 'Response to stress', 'Transcription factor activity', and 'Chloroplast'. Various stress-associated genes with a wide range of biological functions were found, such as signal transduction components (e.g., MAP kinase 4, transcription factors (TFs, e.g., RAP2.11, and reactive oxygen species (ROS scavenging enzymes (e.g., catalase 2, as well as photosynthesis-related genes (e.g., PsaL. Seventeen major TF families including many well-studied members (e.g., AP2-EREBP were also involved in the early response to cold stress. Meanwhile, KEGG pathway analysis uncovered many important pathways, such as 'Plant hormone signal transduction' and 'Starch and sucrose metabolism'. Furthermore, the expression changes of 32 genes under cold and other abiotic stress conditions were validated by real-time RT-PCR. Importantly, most of the tested stress-responsive genes were primarily expressed in mature leaves, stem cambia, and fibrous roots rather than apical buds and young leaves. As a response to cold stress in cassava, an increase

  13. Comfort food is comforting to those most stressed: evidence of the chronic stress response network in high stress women.

    Science.gov (United States)

    Tomiyama, A Janet; Dallman, Mary F; Epel, Elissa S

    2011-11-01

    Chronically stressed rodents who are allowed to eat calorie-dense "comfort" food develop greater mesenteric fat, which in turn dampens hypothalamic-pituitary-adrenocortical (HPA) axis activity. We tested whether similar relations exist in humans, at least cross-sectionally. Fifty-nine healthy premenopausal women were exposed to a standard laboratory stressor to examine HPA response to acute stress and underwent diurnal saliva sampling for basal cortisol and response to dexamethasone administration. Based on perceived stress scores, women were divided into extreme quartiles of low versus high stress categories. We found as hypothesized that the high stress group had significantly greater BMI and sagittal diameter, and reported greater emotional eating. In response to acute lab stressor, the high stress group showed a blunted cortisol response, lower diurnal cortisol levels, and greater suppression in response to dexamethasone. These cross-sectional findings support the animal model, which suggests that long-term adaptation to chronic stress in the face of dense calories result in greater visceral fat accumulation (via ingestion of calorie-dense food), which in turn modulates HPA axis response, resulting in lower cortisol levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Modulation of immune responses in stress by Yoga

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Physiological stress response patterns during a blood donation.

    Science.gov (United States)

    Hoogerwerf, M D; Veldhuizen, I J T; Tarvainen, M P; Merz, E-M; Huis In 't Veld, E M J; de Kort, W L A M; Sluiter, J K; Frings-Dresen, M H W

    2018-03-24

    Donating blood is associated with increased psychological stress. This study investigates whether a blood donation induces physiological stress and if response patterns differ by gender, donation experience and non-acute stress. In 372 donors, physiological stress [blood pressure, pulse rate, pulse rate variability (PRV)] was measured at seven moments during routine donation. PRV was assessed using time domain [root mean square of successive differences (RMSSD)] and frequency domain [high frequency (HF) and low frequency (LF) power] parameters. Non-acute stress was assessed by questionnaire. Shape and significance of time course patterns were assessed by fitting multilevel models for each stress measure and comparing men and women, first-time and experienced donors, and donors with high and low levels of non-acute stress. Significant response patterns were found for all stress measures, where levels of systolic blood pressure (F(1,1315) = 24·2, P blood pressure (F(1,1326) = 50·9, P blood pressure/pulse rate in women; higher pulse rate in first-time donors; higher RMSSD at arrival and from screening until leaving in first-time donors; and higher LF and HF in first-time donors. This study shows an increase in physiological stress related to needle insertion, followed by a decrease when leaving the donation centre. Some group effects were also found. © 2018 International Society of Blood Transfusion.

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

    Directory of Open Access Journals (Sweden)

    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

  18. Critical-like features of stress response in frictional packings

    International Nuclear Information System (INIS)

    Cakir, Abdullah; Silbert, Leonardo E

    2015-01-01

    The mechanical response of static, unconfined, overcompressed face centred cubic, granular arrays is studied using large-scale, discrete element method simulations. Specifically, the stress response due to the application of a localised force perturbation—the Green function technique—is obtained in granular packings generated over several orders of magnitude in both the particle friction coefficient and the applied forcing. We observe crossover behaviour in the mechanical state of the system characterised by the changing nature of the resulting stress response. The transition between anisotropic and isotropic stress response exhibits critical-like features through the identification of a diverging length scale that distinguishes the spatial extent of anisotropic regions from those that display isotropic behaviour. A multidimensional phase diagram is constructed that parameterises the response of the system due to changing friction and force perturbations. (paper)

  19. Lipolysis Response to Endoplasmic Reticulum Stress in Adipose Cells*

    Science.gov (United States)

    Deng, Jingna; Liu, Shangxin; Zou, Liangqiang; Xu, Chong; Geng, Bin; Xu, Guoheng

    2012-01-01

    In obesity and diabetes, adipocytes show significant endoplasmic reticulum (ER) stress, which triggers a series of responses. This study aimed to investigate the lipolysis response to ER stress in rat adipocytes. Thapsigargin, tunicamycin, and brefeldin A, which induce ER stress through different pathways, efficiently activated a time-dependent lipolytic reaction. The lipolytic effect of ER stress occurred with elevated cAMP production and protein kinase A (PKA) activity. Inhibition of PKA reduced PKA phosphosubstrates and attenuated the lipolysis. Although both ERK1/2 and JNK are activated during ER stress, lipolysis is partially suppressed by inhibiting ERK1/2 but not JNK and p38 MAPK and PKC. Thus, ER stress induces lipolysis by activating cAMP/PKA and ERK1/2. In the downstream lipolytic cascade, phosphorylation of lipid droplet-associated protein perilipin was significantly promoted during ER stress but attenuated on PKA inhibition. Furthermore, ER stress stimuli did not alter the levels of hormone-sensitive lipase and adipose triglyceride lipase but caused Ser-563 and Ser-660 phosphorylation of hormone-sensitive lipase and moderately elevated its translocation from the cytosol to lipid droplets. Accompanying these changes, total activity of cellular lipases was promoted to confer the lipolysis. These findings suggest a novel pathway of the lipolysis response to ER stress in adipocytes. This lipolytic activation may be an adaptive response that regulates energy homeostasis but with sustained ER stress challenge could contribute to lipotoxicity, dyslipidemia, and insulin resistance because of persistently accelerated free fatty acid efflux from adipocytes to the bloodstream and other tissues. PMID:22223650

  20. Transcriptome-wide identification of Camellia sinensis WRKY transcription factors in response to temperature stress.

    Science.gov (United States)

    Wu, Zhi-Jun; Li, Xing-Hui; Liu, Zhi-Wei; Li, Hui; Wang, Yong-Xin; Zhuang, Jing

    2016-02-01

    Tea plant [Camellia sinensis (L.) O. Kuntze] is a leaf-type healthy non-alcoholic beverage crop, which has been widely introduced worldwide. Tea is rich in various secondary metabolites, which are important for human health. However, varied climate and complex geography have posed challenges for tea plant survival. The WRKY gene family in plants is a large transcription factor family that is involved in biological processes related to stress defenses, development, and metabolite synthesis. Therefore, identification and analysis of WRKY family transcription factors in tea plant have a profound significance. In the present study, 50 putative C. sinensis WRKY proteins (CsWRKYs) with complete WRKY domain were identified and divided into three Groups (Group I-III) on the basis of phylogenetic analysis results. The distribution of WRKY family transcription factors among plantae, fungi, and protozoa showed that the number of WRKY genes increased in higher plant, whereas the number of these genes did not correspond to the evolutionary relationships of different species. Structural feature and annotation analysis results showed that CsWRKY proteins contained WRKYGQK/WRKYGKK domains and C2H2/C2HC-type zinc-finger structure: D-X18-R-X1-Y-X2-C-X4-7-C-X23-H motif; CsWRKY proteins may be associated with the biological processes of abiotic and biotic stresses, tissue development, and hormone and secondary metabolite biosynthesis. Temperature stresses suggested that the candidate CsWRKY genes were involved in responses to extreme temperatures. The current study established an extensive overview of the WRKY family transcription factors in tea plant. This study also provided a global survey of CsWRKY transcription factors and a foundation of future functional identification and molecular breeding.

  1. Hypothalamic oxytocin mediates social buffering of the stress response.

    Science.gov (United States)

    Smith, Adam S; Wang, Zuoxin

    2014-08-15

    While stressful life events can enhance the risk of mental disorders, positive social interactions can propagate good mental health and normal behavioral routines. Still, the neural systems that promote these benefits are undetermined. Oxytocin is a hormone involved in social behavior and stress; thus, we focus on the impact that social buffering has on the stress response and the governing effects of oxytocin. Female prairie voles (Microtus ochrogaster) were exposed to 1 hour immobilization stress and then recovered alone or with their male partner to characterize the effect of social contact on the behavioral, physiological, and neuroendocrine stress response. In addition, we treated immobilized female voles recovering alone with oxytocin or vehicle and female voles recovering with their male partner with a selective oxytocin receptor antagonist or vehicle. Group sizes varied from 6 to 8 voles (N = 98 total). We found that 1 hour immobilization increased anxiety-like behaviors and circulating levels of corticosterone, a stress hormone, in female prairie voles recovering alone but not the female prairie voles recovering with their male partner. This social buffering by the male partner on biobehavioral responses to stress was accompanied by increased oxytocin release in the paraventricular nucleus of the hypothalamus. Intra-paraventricular nucleus oxytocin injections reduced behavioral and corticosterone responses to immobilization, whereas injections of an oxytocin receptor antagonist blocked the effects of the social buffering. Together, our data demonstrate that paraventricular nucleus oxytocin mediates the social buffering effects on the stress response and thus may be a target for treatment of stress-related disorders. Published by Society of Biological Psychiatry on behalf of Society of Biological Psychiatry.

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

    DEFF Research Database (Denmark)

    Kehlet, H

    1991-01-01

    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......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 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...

  3. Mini-review: Biofilm responses to oxidative stress.

    Science.gov (United States)

    Gambino, Michela; Cappitelli, Francesca

    2016-01-01

    Biofilms constitute the predominant microbial style of life in natural and engineered ecosystems. Facing harsh environmental conditions, microorganisms accumulate reactive oxygen species (ROS), potentially encountering a dangerous condition called oxidative stress. While high levels of oxidative stress are toxic, low levels act as a cue, triggering bacteria to activate effective scavenging mechanisms or to shift metabolic pathways. Although a complex and fragmentary picture results from current knowledge of the pathways activated in response to oxidative stress, three main responses are shown to be central: the existence of common regulators, the production of extracellular polymeric substances, and biofilm heterogeneity. An investigation into the mechanisms activated by biofilms in response to different oxidative stress levels could have important consequences from ecological and economic points of view, and could be exploited to propose alternative strategies to control microbial virulence and deterioration.

  4. The Yeast Environmental Stress Response Regulates Mutagenesis Induced by Proteotoxic Stress

    Science.gov (United States)

    Shor, Erika; Fox, Catherine A.; Broach, James R.

    2013-01-01

    Conditions of chronic stress are associated with genetic instability in many organisms, but the roles of stress responses in mutagenesis have so far been elucidated only in bacteria. Here, we present data demonstrating that the environmental stress response (ESR) in yeast functions in mutagenesis induced by proteotoxic stress. We show that the drug canavanine causes proteotoxic stress, activates the ESR, and induces mutagenesis at several loci in an ESR-dependent manner. Canavanine-induced mutagenesis also involves translesion DNA polymerases Rev1 and Polζ and non-homologous end joining factor Ku. Furthermore, under conditions of chronic sub-lethal canavanine stress, deletions of Rev1, Polζ, and Ku-encoding genes exhibit genetic interactions with ESR mutants indicative of ESR regulating these mutagenic DNA repair processes. Analyses of mutagenesis induced by several different stresses showed that the ESR specifically modulates mutagenesis induced by proteotoxic stress. Together, these results document the first known example of an involvement of a eukaryotic stress response pathway in mutagenesis and have important implications for mechanisms of evolution, carcinogenesis, and emergence of drug-resistant pathogens and chemotherapy-resistant tumors. PMID:23935537

  5. Energetic stress: The reciprocal relationship between energy availability and the stress response.

    Science.gov (United States)

    Harrell, C S; Gillespie, C F; Neigh, G N

    2016-11-01

    The worldwide epidemic of metabolic syndromes and the recognized burden of mental health disorders have driven increased research into the relationship between the two. A maladaptive stress response is implicated in both mental health disorders and metabolic disorders, implicating the hypothalamic-pituitary-adrenal (HPA) axis as a key mediator of this relationship. This review explores how an altered energetic state, such as hyper- or hypoglycemia, as may be manifested in obesity or diabetes, affects the stress response and the HPA axis in particular. We propose that changes in energetic state or energetic demands can result in "energetic stress" that can, if prolonged, lead to a dysfunctional stress response. In this review, we summarize the role of the hypothalamus in modulating energy homeostasis and then briefly discuss the relationship between metabolism and stress-induced activation of the HPA axis. Next, we examine seven mechanisms whereby energetic stress interacts with neuroendocrine stress response systems, including by glucocorticoid signaling both within and beyond the HPA axis; by nutrient-induced changes in glucocorticoid signaling; by impacting the sympathetic nervous system; through changes in other neuroendocrine factors; by inducing inflammatory changes; and by altering the gut-brain axis. Recognizing these effects of energetic stress can drive novel therapies and prevention strategies for mental health disorders, including dietary intervention, probiotics, and even fecal transplant. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Chronic stress affects immunologic but not cardiovascular responsiveness to acute psychological stress in humans

    NARCIS (Netherlands)

    Benschop, R. J.; Brosschot, J. F.; Godaert, G. L.; de Smet, M. B.; Geenen, R.; Olff, M.; Heijnen, C. J.; Ballieux, R. E.

    1994-01-01

    This study deals with the effect of chronic stress on physiological responsiveness to an acute psychological stressor in male high school teachers. Chronic stress was operationalized as the self-reported number of everyday problems. Twenty-seven subjects reporting extremely low or high numbers of

  7. Rapid biotic homogenization of marine fish assemblages

    Science.gov (United States)

    Magurran, Anne E.; Dornelas, Maria; Moyes, Faye; Gotelli, Nicholas J.; McGill, Brian

    2015-01-01

    The role human activities play in reshaping biodiversity is increasingly apparent in terrestrial ecosystems. However, the responses of entire marine assemblages are not well-understood, in part, because few monitoring programs incorporate both spatial and temporal replication. Here, we analyse an exceptionally comprehensive 29-year time series of North Atlantic groundfish assemblages monitored over 5° latitude to the west of Scotland. These fish assemblages show no systematic change in species richness through time, but steady change in species composition, leading to an increase in spatial homogenization: the species identity of colder northern localities increasingly resembles that of warmer southern localities. This biotic homogenization mirrors the spatial pattern of unevenly rising ocean temperatures over the same time period suggesting that climate change is primarily responsible for the spatial homogenization we observe. In this and other ecosystems, apparent constancy in species richness may mask major changes in species composition driven by anthropogenic change. PMID:26400102

  8. A Wheat R2R3-type MYB Transcription Factor TaODORANT1 Positively Regulates Drought and Salt Stress Responses in Transgenic Tobacco Plants

    Directory of Open Access Journals (Sweden)

    Qiuhui Wei

    2017-08-01

    Full Text Available MYB transcription factors play important roles in plant responses to biotic and abiotic stress. In this study, TaODORANT1, a R2R3-MYB gene, was cloned from wheat (Triticum aestivum L.. TaODORANT1 was localized in the nucleus and functioned as a transcriptional activator. TaODORANT1 was up-regulated in wheat under PEG6000, NaCl, ABA, and H2O2 treatments. TaODORANT1-overexpressing transgenic tobacco plants exhibited higher relative water content and lower water loss rate under drought stress, as well as lower Na+ accumulation in leaves under salt stress. The transgenic plants showed higher CAT activity but lower ion leakage, H2O2 and malondialdehyde contents under drought and salt stresses. Besides, the transgenic plants also exhibited higher SOD activity under drought stress. Our results also revealed that TaODORANT1 overexpression up-regulated the expression of several ROS- and stress-related genes in response to both drought and salt stresses, thus enhancing transgenic tobacco plants tolerance. Our studies demonstrate that TaODORANT1 positively regulates plant tolerance to drought and salt stresses.

  9. Stress response and virulence in Vibrio anguillarum

    OpenAIRE

    Weber, Barbara

    2010-01-01

    Bacteria use quorum sensing, a cell to cell signaling mechanism mediated by small molecules that are produced by specific signal molecule synthases, to regulate gene expression in response to population density. In Vibrio anguillarum, the quorum-sensing phosphorelay channels information from three hybrid sensor kinases VanN, VanQ, CqsS that sense signal molecules produced by the synthases VanM, VanS and CqsA, onto the phosphotransferase VanU, to regulate activity of the response regulator Van...

  10. Responses of neurons to extreme osmomechanical stress.

    Science.gov (United States)

    Wan, X; Harris, J A; Morris, C E

    1995-05-01

    Neurons are often regarded as fragile cells, easily destroyed by mechanical and osmotic insult. The results presented here demonstrate that this perception needs revision. Using extreme osmotic swelling, we show that molluscan neurons are astonishingly robust. In distilled water, a heterogeneous population of Lymnaea stagnalis CNS neurons swelled to several times their initial volume, yet had a ST50 (survival time for 50% of cells) > 60 min. Cells that were initially bigger survived longer. On return to normal medium, survivors were able, over the next 24 hr, to rearborize. Reversible membrane capacitance changes corresponding to about 0.7 muF/cm2 of apparent surface area accompanied neuronal swelling and shrinking in hypo- and hyperosmotic solutions; reversible changes in cell surface area evidently contributed to the neurons' ability to accommodate hydrostatic pressures then recover. The reversible membrane area/capacitance changes were not dependent on extracellular Ca2+. Neurons were monitored for potassium currents during direct mechanical inflation and during osmotically driven inflation. The latter but not the former stimulus routinely elicited small potassium currents, suggesting that tension increases activate the currents only if additional disruption of the cortex has occurred. Under stress in distilled water, a third of the neurons displayed a quite unexpected behavior: prolonged writhing of peripheral regions of the soma. This suggested that a plasma membrane-linked contractile machinery (presumably actomyosin) might contribute to the neurons' mechano-osmotic robustness by restricting water influx. Consistent with this possibility, 1 mM N-ethyl-maleimide, which inhibits myosin ATPase, decreased the ST50 to 18 min, rendered the survival time independent of initial size, and abolished writhing activity. For neurons, active mechanical resistance of the submembranous cortex, along with the mechanical compliance supplied by insertion or eversion of membrane

  11. Systems responses to progressive water stress in durum wheat.

    Directory of Open Access Journals (Sweden)

    Dimah Z Habash

    Full Text Available Durum wheat is susceptible to terminal drought which can greatly decrease grain yield. Breeding to improve crop yield is hampered by inadequate knowledge of how the physiological and metabolic changes caused by drought are related to gene expression. To gain better insight into mechanisms defining resistance to water stress we studied the physiological and transcriptome responses of three durum breeding lines varying for yield stability under drought. Parents of a mapping population (Lahn x Cham1 and a recombinant inbred line (RIL2219 showed lowered flag leaf relative water content, water potential and photosynthesis when subjected to controlled water stress time transient experiments over a six-day period. RIL2219 lost less water and showed constitutively higher stomatal conductance, photosynthesis, transpiration, abscisic acid content and enhanced osmotic adjustment at equivalent leaf water compared to parents, thus defining a physiological strategy for high yield stability under water stress. Parallel analysis of the flag leaf transcriptome under stress uncovered global trends of early changes in regulatory pathways, reconfiguration of primary and secondary metabolism and lowered expression of transcripts in photosynthesis in all three lines. Differences in the number of genes, magnitude and profile of their expression response were also established amongst the lines with a high number belonging to regulatory pathways. In addition, we documented a large number of genes showing constitutive differences in leaf transcript expression between the genotypes at control non-stress conditions. Principal Coordinates Analysis uncovered a high level of structure in the transcriptome response to water stress in each wheat line suggesting genome-wide co-ordination of transcription. Utilising a systems-based approach of analysing the integrated wheat's response to water stress, in terms of biological robustness theory, the findings suggest that each durum

  12. The Effect of Music on the Human Stress Response

    Science.gov (United States)

    Thoma, Myriam V.; La Marca, Roberto; Brönnimann, Rebecca; Finkel, Linda; Ehlert, Ulrike; Nater, Urs M.

    2013-01-01

    Background Music listening has been suggested to beneficially impact health via stress-reducing effects. However, the existing literature presents itself with a limited number of investigations and with discrepancies in reported findings that may result from methodological shortcomings (e.g. small sample size, no valid stressor). It was the aim of the current study to address this gap in knowledge and overcome previous shortcomings by thoroughly examining music effects across endocrine, autonomic, cognitive, and emotional domains of the human stress response. Methods Sixty healthy female volunteers (mean age = 25 years) were exposed to a standardized psychosocial stress test after having been randomly assigned to one of three different conditions prior to the stress test: 1) relaxing music (‘Miserere’, Allegri) (RM), 2) sound of rippling water (SW), and 3) rest without acoustic stimulation (R). Salivary cortisol and salivary alpha-amylase (sAA), heart rate (HR), respiratory sinus arrhythmia (RSA), subjective stress perception and anxiety were repeatedly assessed in all subjects. We hypothesized that listening to RM prior to the stress test, compared to SW or R would result in a decreased stress response across all measured parameters. Results The three conditions significantly differed regarding cortisol response (p = 0.025) to the stressor, with highest concentrations in the RM and lowest in the SW condition. After the stressor, sAA (p=0.026) baseline values were reached considerably faster in the RM group than in the R group. HR and psychological measures did not significantly differ between groups. Conclusion Our findings indicate that music listening impacted the psychobiological stress system. Listening to music prior to a standardized stressor predominantly affected the autonomic nervous system (in terms of a faster recovery), and to a lesser degree the endocrine and psychological stress response. These findings may help better understanding the

  13. Plant reference genes for development and stress response studies

    Indian Academy of Sciences (India)

    Joyous T Joseph

    2018-02-09

    Feb 9, 2018 ... HKGs are constitutive genes required for the maintenance of basic cellular functions like cell ... abiotic, biotic, and developmental factors affecting the cells in which they express. ..... expression. Theory Biosci. 131 215–223.

  14. Stress-related cortisol responsivity modulates prospective memory.

    Science.gov (United States)

    Glienke, K; Piefke, M

    2017-12-01

    It is known that there is inter-individual variation in behavioural and physiological stress reactions to the same stressor. The present study aimed to examine the impact of cortisol responsivity on performance in a complex real life-like prospective memory (PM) paradigm by a re-analysis of data published previously, with a focus on the taxonomy of cognitive dimensions of PM. Twenty-one male subjects were stressed with the Socially Evaluated Cold Pressor Test (SECPT) before the planning of intentions. Another group of 20 males underwent a control procedure. Salivary cortisol was measured to assess the intensity of the biological stress response. Additionally, participants rated the subjective experience of stress on a 5-point rating scale. Stressed participants were post-hoc differentiated in high (n = 11) and low cortisol responders (n = 10). Cortisol niveau differed significantly between the two groups, whereas subjective stress ratings did not. PM performance of low cortisol responders was stable across time and the PM performance of controls declined. High cortisol responders showed a nominally weaker PM retrieval across the early trails and significantly improved only on the last trial. The data demonstrate for the first time that participants with a low cortisol responsivity may benefit from stress exposure before the planning phase of PM. PM performance of high cortisol responders shows a more inconsistent pattern, which may be interpreted in the sense of a recency effect in PM retrieval. Alternatively, high cortisol responses may have a deteriorating effect on PM retrieval, which disappeared on the last trials of the task as a result of the decrease of cortisol levels across time. Importantly, the data also demonstrate that the intensity of cortisol responses does not necessarily correspond to the intensity of the mental experience of stress. © 2017 British Society for Neuroendocrinology.

  15. UV-B Irradiation Changes Specifically the Secondary Metabolite Profile in Broccoli Sprouts: Induced Signaling Overlaps with Defense Response to Biotic Stressors

    Science.gov (United States)

    Mewis, Inga; Schreiner, Monika; Nguyen, Chau Nhi; Krumbein, Angelika; Ulrichs, Christian; Lohse, Marc; Zrenner, Rita

    2012-01-01

    Only a few environmental factors have such a pronounced effect on plant growth and development as ultraviolet light (UV). Concerns have arisen due to increased UV-B radiation reaching the Earth’s surface as a result of stratospheric ozone depletion. Ecologically relevant low to moderate UV-B doses (0.3–1 kJ m–2 d–1) were applied to sprouts of the important vegetable crop Brassica oleracea var. italica (broccoli), and eco-physiological responses such as accumulation of non-volatile secondary metabolites were related to transcriptional responses with Agilent One-Color Gene Expression Microarray analysis using the 2×204 k format Brassica microarray. UV-B radiation effects have usually been linked to increases in phenolic compounds. As expected, the flavonoids kaempferol and quercetin accumulated in broccoli sprouts (the aerial part of the seedlings) 24 h after UV-B treatment. A new finding is the specific UV-B-mediated induction of glucosinolates (GS), especially of 4-methylsulfinylbutyl GS and 4-methoxy-indol-3-ylmethyl GS, while carotenoids and Chl levels remained unaffected. Accumulation of defensive GS metabolites was accompanied by increased expression of genes associated with salicylate and jasmonic acid signaling defense pathways and up-regulation of genes responsive to fungal and bacterial pathogens. Concomitantly, plant pre-exposure to moderate UV-B doses had negative effects on the performance of the caterpillar Pieris brassicae (L.) and on the population growth of the aphid Myzus persicae (Sulzer). Moreover, insect-specific induction of GS in broccoli sprouts was affected by UV-B pre-treatment. PMID:22773681

  16. Exercise-Induced Oxidative Stress Responses in the Pediatric Population

    Directory of Open Access Journals (Sweden)

    Alexandra Avloniti

    2017-01-01

    Full Text Available Adults demonstrate an upregulation of their pro- and anti-oxidant mechanisms in response to acute exercise while systematic exercise training enhances their antioxidant capacity, thereby leading to a reduced generation of free radicals both at rest and in response to exercise stress. However, less information exists regarding oxidative stress responses and the underlying mechanisms in the pediatric population. Evidence suggests that exercise-induced redox perturbations may be valuable in order to monitor exercise-induced inflammatory responses and as such training overload in children and adolescents as well as monitor optimal growth and development. The purpose of this review was to provide an update on oxidative stress responses to acute and chronic exercise in youth. It has been documented that acute exercise induces age-specific transient alterations in both oxidant and antioxidant markers in children and adolescents. However, these responses seem to be affected by factors such as training phase, training load, fitness level, mode of exercise etc. In relation to chronic adaptation, the role of training on oxidative stress adaptation has not been adequately investigated. The two studies performed so far indicate that children and adolescents exhibit positive adaptations of their antioxidant system, as adults do. More studies are needed in order to shed light on oxidative stress and antioxidant responses, following acute exercise and training adaptations in youth. Available evidence suggests that small amounts of oxidative stress may be necessary for growth whereas the transition to adolescence from childhood may promote maturation of pro- and anti-oxidant mechanisms. Available evidence also suggests that obesity may negatively affect basal and exercise-related antioxidant responses in the peripubertal period during pre- and early-puberty.

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

    Directory of Open Access Journals (Sweden)

    Masaaki Adachi

    2009-11-01

    Full Text Available 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.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.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.

  18. Reproduction elevates the corticosterone stress response in common fruit bats.

    Science.gov (United States)

    Klose, Stefan M; Smith, Carolynn L; Denzel, Andrea J; Kalko, Elisabeth K V

    2006-04-01

    Changes in reproductive state or the environment may affect the sensitivity of the hypothalamic-pituitary-andrenal (HPA) axis. However, little is known about the dynamics of the resulting corticosteroid stress response, in particular in tropical mammals. In this study, we address the modulation of corticosterone release in response to different reproductive conditions and seasonality in 326 free-living common fruit-eating bats (Artibeus jamaicensis) on Barro Colorado Island in Panama during dry and wet seasons. We present strong evidence that stress sensitivity is primarily modulated by reproductive condition. In reproductively active females, corticosterone increases were more rapid and reached higher levels, but also decreased significantly faster than in inactive females. The corticosterone response was weaker in reproducing males than in females and delayed compared to non-reproductive males. Testes volume in reproductively active males was negatively correlated with corticosterone concentrations. Our findings suggest differentiated dynamics in the corticosterone stress response between sexes, potentially reflecting conflicting ecological demands. In females, a strong acute corticosterone response may represent high stress- and risk-sensitivity that facilitates escape and thus helps to protect reproduction. In males, suppression during reproductive activity could reflect lowered stress sensitivity to avoid chronically elevated corticosterone levels in times of frequent aggressive and therefore costly inter-male encounters.

  19. A role for SR proteins in plant stress responses.

    Science.gov (United States)

    Duque, Paula

    2011-01-01

    Members of the SR (serine/arginine-rich) protein gene family are key players in the regulation of alternative splicing, an important means of generating proteome diversity and regulating gene expression. In plants, marked changes in alternative splicing are induced by a wide variety of abiotic stresses, suggesting a role for this highly versatile gene regulation mechanism in the response to environmental cues. In support of this notion, the expression of plant SR proteins is stress-regulated at multiple levels, with environmental signals controlling their own alternative splicing patterns, phosphorylation status and subcellular distribution. Most importantly, functional links between these RNA-binding proteins and plant stress tolerance are beginning to emerge, including a role in the regulation of abscisic acid (ABA) signaling. Future identification of the physiological mRNA targets of plant SR proteins holds much promise for the elucidation of the molecular mechanisms underlying their role in the response to abiotic stress.

  20. Proteomics analysis of alfalfa response to heat stress.

    Directory of Open Access Journals (Sweden)

    Weimin Li

    Full Text Available The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin seedlings were exposed to 25 °C (control and 40 °C (heat stress in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE, and differentially expressed protein spots were identified by mass spectrometry (MS. Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa.

  1. Stress and fear responses in the teleost pallium

    DEFF Research Database (Denmark)

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

    2015-01-01

    Evolution has resulted in behavioural responses to threat which show extensive similarities between different animal species. The reaction to predator cues is one example of such prevailing responses, and functional homologies to mammalian limbic regions involved in threat-sensitive behaviour hav...... to chemical alarm cues, but this effect did not reach the level of statistical significance. Hence, limbic responses to stress and fear, akin to those seen in extant mammals, are also present in the teleost lineage...

  2. Hormonal contraception use alters stress responses and emotional memory

    OpenAIRE

    Nielsen, Shawn E.; Segal, Sabrina K.; Worden, Ian V.; Yim, Ilona S.; Cahill, Larry

    2012-01-01

    Emotionally arousing material is typically better remembered than neutral material. Since norepinephrine and cortisol interact to modulate emotional memory, sex-related influences on stress responses may be related to sex differences in emotional memory. Two groups of healthy women – one naturally cycling (NC women, N = 42) and one using hormonal contraceptives (HC women, N = 36) – viewed emotionally arousing and neutral images. Immediately after, they were assigned to Cold Pressor Stress (CP...

  3. Enhanced effects of biotic interactions on predicting multispecies spatial distribution of submerged macrophytes after eutrophication.

    Science.gov (United States)

    Song, Kun; Cui, Yichong; Zhang, Xijin; Pan, Yingji; Xu, Junli; Xu, Kaiqin; Da, Liangjun

    2017-10-01

    Water eutrophication creates unfavorable environmental conditions for submerged macrophytes. In these situations, biotic interactions may be particularly important for explaining and predicting the submerged macrophytes occurrence. Here, we evaluate the roles of biotic interactions in predicting spatial occurrence of submerged macrophytes in 1959 and 2009 for Dianshan Lake in eastern China, which became eutrophic since the 1980s. For the four common species occurred in 1959 and 2009, null species distribution models based on abiotic variables and full models based on both abiotic and biotic variables were developed using generalized linear model (GLM) and boosted regression trees (BRT) to determine whether the biotic variables improved the model performance. Hierarchical Bayesian-based joint species distribution models capable of detecting paired biotic interactions were established for each species in both periods to evaluate the changes in the biotic interactions. In most of the GLM and BRT models, the full models showed better performance than the null models in predicting the species presence/absence, and the relative importance of the biotic variables in the full models increased from less than 50% in 1959 to more than 50% in 2009 for each species. Moreover, co-occurrence correlation of each paired species interaction was higher in 2009 than that in 1959. The findings suggest biotic interactions that tend to be positive play more important roles in the spatial distribution of multispecies assemblages of macrophytes and should be included in prediction models to improve prediction accuracy when forecasting macrophytes' distribution under eutrophication stress.

  4. A literature review on biotic homogenization

    OpenAIRE

    Guangmei Wang; Jingcheng Yang; Chuangdao Jiang; Hongtao Zhao; Zhidong Zhang

    2009-01-01

    Biotic homogenization is the process whereby the genetic, taxonomic and functional similarity of two or more biotas increases over time. As a new research agenda for conservation biogeography, biotic homogenization has become a rapidly emerging topic of interest in ecology and evolution over the past decade. However, research on this topic is rare in China. Herein, we introduce the development of the concept of biotic homogenization, and then discuss methods to quantify its three components (...

  5. Sex differences in chronic stress responses and Alzheimer's disease.

    Science.gov (United States)

    Yan, Yan; Dominguez, Sky; Fisher, Daniel W; Dong, Hongxin

    2018-02-01

    Clinical studies indicate that Alzheimer's disease (AD) disproportionately affects women in both disease prevalence and severity, but the mechanisms underlying this sex divergence are unknown. Though some have suggested this difference in risk is a reflection of known differences in longevity between men and women, mounting clinical and preclinical evidence supports women also having intrinsic susceptibilities towards the disease. While a number of potential risk factors have been hypothesized to affect these differences in risks, none have been definitively verified. In this review, we discuss a novel hypothesis whereby women's susceptibility to chronic stress also mediates increased risk for AD. As stress is a risk factor for AD, and women are twice as likely to develop mood disorders where stress is a major etiology, it is possible that sex dimorphisms in stress responses contribute to the increase in women with AD. In line with this, sex divergence in biochemical responses to stress have been noted along the hypothalamic-pituitary-adrenal (HPA) axis and among known molecular effectors of AD, with crosstalk between these processes also being likely. In addition, activation of the cortical corticotrophin-releasing factor receptor 1 (CRF1) signaling pathway leads to distinct female-biased increases in molecules associated with AD pathogenesis. Therefore, the different biochemical responses to stress between women and men may represent an intrinsic, sex-dependent risk factor for AD.

  6. Hormonal contraception use alters stress responses and emotional memory.

    Science.gov (United States)

    Nielsen, Shawn E; Segal, Sabrina K; Worden, Ian V; Yim, Ilona S; Cahill, Larry

    2013-02-01

    Emotionally arousing material is typically better remembered than neutral material. Since norepinephrine and cortisol interact to modulate emotional memory, sex-related influences on stress responses may be related to sex differences in emotional memory. Two groups of healthy women - one naturally cycling (NC women, n=42) and one using hormonal contraceptives (HC women, n=36) - viewed emotionally arousing and neutral images. Immediately after, they were assigned to Cold Pressor Stress (CPS) or a control procedure. One week later, participants received a surprise free recall test. Saliva samples were collected and later assayed for salivary alpha-amylase (biomarker for norepinephrine) and cortisol. Compared to NC women, HC women exhibited significantly blunted stress hormone responses to the images and CPS. Recall of emotional images differed between HC and NC women depending on noradrenergic and cortisol responses. These findings may have important implications for understanding the neurobiology of emotional memory disorders, especially those that disproportionately affect women. Published by Elsevier B.V.

  7. The Arabidopsis thaliana RNA editing factor SLO2, which affects the mitochondrial electron transport chain, participates in multiple stress and hormone responses.

    Science.gov (United States)

    Zhu, Qiang; Dugardeyn, Jasper; Zhang, Chunyi; Mühlenbock, Per; Eastmond, Peter J; Valcke, Roland; De Coninck, Barbara; Oden, Sevgi; Karampelias, Michael; Cammue, Bruno P A; Prinsen, Els; Van Der Straeten, Dominique

    2014-02-01

    Recently, we reported that the novel mitochondrial RNA editing factor SLO2 is essential for mitochondrial electron transport, and vital for plant growth through regulation of carbon and energy metabolism. Here, we show that mutation in SLO2 causes hypersensitivity to ABA and insensitivity to ethylene, suggesting a link with stress responses. Indeed, slo2 mutants are hypersensitive to salt and osmotic stress during the germination stage, while adult plants show increased drought and salt tolerance. Moreover, slo2 mutants are more susceptible to Botrytis cinerea infection. An increased expression of nuclear-encoded stress-responsive genes, as well as mitochondrial-encoded NAD genes of complex I and genes of the alternative respiratory pathway, was observed in slo2 mutants, further enhanced by ABA treatment. In addition, H2O2 accumulation and altered amino acid levels were recorded in slo2 mutants. We conclude that SLO2 is required for plant sensitivity to ABA, ethylene, biotic, and abiotic stress. Although two stress-related RNA editing factors were reported very recently, this study demonstrates a unique role of SLO2, and further supports a link between mitochondrial RNA editing events and stress response.

  8. Coping as a mediator of the relationship between stress mindset and psychological stress response: a pilot study.

    Science.gov (United States)

    Horiuchi, Satoshi; Tsuda, Akira; Aoki, Shuntaro; Yoneda, Kenichiro; Sawaguchi, Yusuke

    2018-01-01

    Coping, the cognitive and behavioral effort required to manage the effects of stressors, is important in determining psychological stress responses (ie, the emotional, behavioral, and cognitive responses to stressors). Coping was classified into categories of emotional expression (eg, negative feelings and thoughts), emotional support seeking (eg, approaching loved ones to request encouragement), cognitive reinterpretation (eg, reframing a problem positively), and problem solving (eg, working to solve the problem). Stress mindset refers to the belief that stress has enhancing (stress-is-enhancing mindset) or debilitating consequences (stress-is-debilitating mindset). This study examined whether coping mediated the relationship between stress mindset and psychological stress responses. Psychological stress responses were conceptualized as depression-anxiety, irritability-anger, and helplessness. The following two hypotheses were tested: 1) a stronger stress-is-enhancing mindset is associated with less frequent use of emotional expression, emotional support seeking, and problem solving, which in turn is associated with lower levels of depression-anxiety, irritability-anger, and helplessness; 2) a stronger stress-is-debilitating mindset is associated with more frequent use of these coping strategies, which in turn is associated with higher levels of these psychological stress responses. The participants were 30 male and 94 female undergraduate and graduate students (mean age =20.4 years). Stress mindset, coping, and psychological stress responses were measured using self-report questionnaires. Six mediation analyses were performed with stress-is-enhancing mindset or stress-is-debilitating mindset as the independent variable, one of the psychological stress responses as the dependent variable, and the four coping strategies as mediators. Emotional expression partially mediated the relationship between a strong stress-is-debilitating mindset and higher irritability

  9. Transcriptional responses of Arabidopsis thaliana plants to As (V stress

    Directory of Open Access Journals (Sweden)

    Yuan Joshua S

    2008-08-01

    Full Text Available Abstract Background Arsenic is toxic to plants and a common environmental pollutant. There is a strong chemical similarity between arsenate [As (V] and phosphate (Pi. Whole genome oligonucleotide microarrays were employed to investigate the transcriptional responses of Arabidopsis thaliana plants to As (V stress. Results Antioxidant-related genes (i.e. coding for superoxide dismutases and peroxidases play prominent roles in response to arsenate. The microarray experiment revealed induction of chloroplast Cu/Zn superoxide dismutase (SOD (at2g28190, Cu/Zn SOD (at1g08830, as well as an SOD copper chaperone (at1g12520. On the other hand, Fe SODs were strongly repressed in response to As (V stress. Non-parametric rank product statistics were used to detect differentially expressed genes. Arsenate stress resulted in the repression of numerous genes known to be induced by phosphate starvation. These observations were confirmed with qRT-PCR and SOD activity assays. Conclusion Microarray data suggest that As (V induces genes involved in response to oxidative stress and represses transcription of genes induced by phosphate starvation. This study implicates As (V as a phosphate mimic in the cell by repressing genes normally induced when available phosphate is scarce. Most importantly, these data reveal that arsenate stress affects the expression of several genes with little or unknown biological functions, thereby providing new putative gene targets for future research.

  10. Immune and stress responses in oysters with insights on adaptation.

    Science.gov (United States)

    Guo, Ximing; He, Yan; Zhang, Linlin; Lelong, Christophe; Jouaux, Aude

    2015-09-01

    Oysters are representative bivalve molluscs that are widely distributed in world oceans. As successful colonizers of estuaries and intertidal zones, oysters are remarkably resilient against harsh environmental conditions including wide fluctuations in temperature and salinity as well as prolonged air exposure. Oysters have no adaptive immunity but can thrive in microbe-rich estuaries as filter-feeders. These unique adaptations make oysters interesting models to study the evolution of host-defense systems. Recent advances in genomic studies including sequencing of the oyster genome have provided insights into oyster's immune and stress responses underlying their amazing resilience. Studies show that the oyster genomes are highly polymorphic and complex, which may be key to their resilience. The oyster genome has a large gene repertoire that is enriched for immune and stress response genes. Thousands of genes are involved in oyster's immune and stress responses, through complex interactions, with many gene families expanded showing high sequence, structural and functional diversity. The high diversity of immune receptors and effectors may provide oysters with enhanced specificity in immune recognition and response to cope with diverse pathogens in the absence of adaptive immunity. Some members of expanded immune gene families have diverged to function at different temperatures and salinities or assumed new roles in abiotic stress response. Most canonical innate immunity pathways are conserved in oysters and supported by a large number of diverse and often novel genes. The great diversity in immune and stress response genes exhibited by expanded gene families as well as high sequence and structural polymorphisms may be central to oyster's adaptation to highly stressful and widely changing environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Effect of childhood physical abuse on cortisol stress response.

    Science.gov (United States)

    Carpenter, Linda L; Shattuck, Thaddeus T; Tyrka, Audrey R; Geracioti, Thomas D; Price, Lawrence H

    2011-03-01

    Abuse and neglect are highly prevalent in children and have enduring neurobiological effects. Stressful early life environments perturb the hypothalamic-pituitary-adrenal (HPA) axis, which in turn may predispose to psychiatric disorders in adulthood. However, studies of childhood maltreatment and adult HPA function have not yet rigorously investigated the differential effects of maltreatment subtypes, including physical abuse. In this study, we sought to replicate our previous finding that childhood maltreatment was associated with attenuated cortisol responses to stress and determine whether the type of maltreatment was a determinant of the stress response. Salivary cortisol response to the Trier Social Stress Test (TSST) was examined in a non-clinical sample of women (n = 110). Subjects had no acute medical problems and were not seeking psychiatric treatment. Effects of five maltreatment types, as measured by the Childhood Trauma Questionnaire, on cortisol response to the TSST were investigated. To further examine the significant (p < 0.005) effect of one maltreatment type, women with childhood physical abuse (PA) (n = 20) were compared to those without past PA (n = 90). Women reporting childhood PA displayed a significantly blunted cortisol response to the TSST compared with subjects without PA, after controlling for estrogen use, age, other forms of maltreatment, and other potential confounds. There were no differences between PA and control groups with regard to physiological arousal during the stress challenge. In a non-clinical sample of women with minimal or no current psychopathology, physical abuse is associated with a blunted cortisol response to a psychosocial stress task.

  12. Social stress response in adolescents with bipolar disorder.

    Science.gov (United States)

    Casement, Melynda D; Goldstein, Tina R; Gratzmiller, Sarah M; Franzen, Peter L

    2018-05-01

    Theoretical models posit that stressors contribute to the onset and maintenance of bipolar disorder in adolescence through disruptions in stress physiology, but physiological response to stressors has not been evaluated in adolescents with bipolar illness. The present study tests the hypothesis that adolescents with bipolar disorder will have greater reactivity to a laboratory social stress task than healthy adolescents. Adolescents with bipolar illness (n = 27) and healthy adolescents (n = 28) completed a modified version of the Trier Social Stress Task. Stress response was assessed using high frequency heart rate variability (HF-HRV), heart rate (HR), mean arterial blood pressure (MAP), salivary cortisol, and subjective stress. Multilevel models were used to test for group differences in resting-state physiology, and stress reactivity and recovery. Adolescents with bipolar disorder had greater reactivity in HF-HRV (z = 3.32), but blunted reactivity in MAP (z = -3.08) and cortisol (z = -2.60), during the stressor compared to healthy adolescents. They also had lower resting HF-HRV (z = -3.49) and cortisol (z = -2.86), and higher resting HR (z = 3.56), than healthy adolescents. These results indicate that bipolar disorder is associated with disruptions in autonomic and endocrine response to stress during adolescence, including greater HF-HRV reactivity. Further research should evaluate whether these individual differences in stress physiology precede and predict the onset of mood episodes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Eccentric-exercise induced inflammation attenuates the vascular responses to mental stress

    NARCIS (Netherlands)

    Paine, N.J.; Ring, C.; Aldred, S.; Bosch, J.A.; Wadley, A.J.; Veldhuijzen van Zanten, J.J.C.S.

    2013-01-01

    Mental stress has been identified as a trigger of myocardial infarction (MI), with inflammation and vascular responses to mental stress independently implicated as contributing factors. This study examined whether inflammation moderates the vascular responses to mental stress. Eighteen healthy male

  14. Respiratory Effects and Systemic Stress Response Following ...

    Science.gov (United States)

    Previous studies have demonstrated that exposure to the pulmonary irritant ozone causes myriad systemic metabolic and pulmonary effects attributed to sympathetic and hypothalamus-pituitary-adrenal (HPA) axis activation, which are exacerbated in metabolically impaired models. We examined respiratory and systemic effects following exposure to a sensory irritant acrolein to elucidate the systemic and pulmonary consequences in healthy and diabetic rat models. Male Wistar and Goto Kakizaki (GK) rats, a nonobese type II diabetic Wistar-derived model, were exposed by inhalation to 0, 2, or 4 ppm acrolein, 4 h/d for 1 or 2 days. Exposure at 4 ppm significantly increased pulmonary and nasal inflammation in both strains with vascular protein leakage occurring only in the nose. Acrolein exposure (4 ppm) also caused metabolic impairment by inducing hyperglycemia and glucose intolerance (GK > Wistar). Serum total cholesterol (GKs only), low-density lipoprotein (LDL) cholesterol (both strains), and free fatty acids (GK > Wistar) levels increased; however, no acrolein-induced changes were noted in branched-chain amino acid or insulin levels. These responses corresponded with a significant increase in corticosterone and modest but insignificant increases in adrenaline in both strains, suggesting activation of the HPA axis. Collectively, these data demonstrate that acrolein exposure has a profound effect on nasal and pulmonary inflammation, as well as glucose and lipid metabolis

  15. Response of Saccharomyces cerevisiae to cadmium stress

    International Nuclear Information System (INIS)

    Moreira, Luciana Mara Costa; Ribeiro, Frederico Haddad; Neves, Maria Jose; Porto, Barbara Abranches Araujo; Amaral, Angela M.; Menezes, Maria Angela B.C.; Rosa, Carlos Augusto

    2009-01-01

    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 + and Na + ) 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)

  16. Response of Saccharomyces cerevisiae to cadmium stress

    Energy Technology Data Exchange (ETDEWEB)

    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)

  17. Psychological stress during exercise: immunoendocrine and oxidative responses.

    Science.gov (United States)

    Huang, Chun-Jung; Webb, Heather E; Evans, Ronald K; McCleod, Kelly A; Tangsilsat, Supatchara E; Kamimori, Gary H; Acevedo, Edmund O

    2010-12-01

    The purpose of this study was to examine the changes in catecholamines (epinephrine [EPI] and norepinephrine [NE]), interleukin-2 (IL-2) and a biomarker of oxidative stress (8-isoprostane) in healthy individuals who were exposed to a dual challenge (physical and psychological stress). Furthermore, this study also examined the possible relationships between catecholamines (NE and EPI) and 8-isoprostane and between IL-2 and 8-isoprostane following a combined physical and psychological challenge. Seven healthy male subjects completed two experimental conditions. The exercise-alone condition (EAC) consisted of cycling at 60% VO(2max) for 37 min, while the dual-stress condition (DSC) included 20 min of a mental challenge while cycling. DSC showed greater EPI and 8-isoprostane levels (significant condition by time interaction). NE and IL-2 revealed significant change across time in both conditions. In addition, following dual stress, EPI area-under-the-curve (AUC) demonstrated a positive correlation with NE AUC and IL-2 AUC. NE AUC was positively correlated with IL-2 AUC and peak 8-isoprostane, and peak IL-2 was positively correlated with peak 8-isoprostane in response to a dual stress. The potential explanation for elevated oxidative stress during dual stress may be through the effects of the release of catecholamines and IL-2. These findings may further provide the potential explanation that dual stress alters physiological homeostasis in many occupations including firefighting, military operations and law enforcement. A greater understanding of these responses to stress can assist in finding strategies (e.g. exercise training) to overcome the inherent psychobiological challenges associated with physically and mentally demanding professions.

  18. Stretching the stress boundary: Linking air pollution health effects to a neurohormonal stress response.

    Science.gov (United States)

    Kodavanti, Urmila P

    2016-12-01

    Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer's and diabetes. A neurohormonal stress response (referred to here as a systemic response produced by activation of the sympathetic nervous system and hypothalamus-pituitary-adrenal (HPA)-axis) has been implicated in a variety of psychological and physical stresses, which involves immune and metabolic homeostatic mechanisms affecting all organs in the body. In this review, we provide new evidence for the involvement of this well-characterized neurohormonal stress response in mediating systemic and pulmonary effects of a prototypic air pollutant - ozone. A plethora of systemic metabolic and immune effects are induced in animals exposed to inhaled pollutants, which could result from increased circulating stress hormones. The release of adrenal-derived stress hormones in response to ozone exposure not only mediates systemic immune and metabolic responses, but by doing so, also modulates pulmonary injury and inflammation. With recurring pollutant exposures, these effects can contribute to multi-organ chronic conditions associated with air pollution. This review will cover, 1) the potential mechanisms by which air pollutants can initiate the relay of signals from respiratory tract to brain through trigeminal and vagus nerves, and activate stress responsive regions including hypothalamus; and 2) the contribution of sympathetic and HPA-axis activation in mediating systemic homeostatic metabolic and immune effects of ozone in various organs. The potential contribution of chronic environmental stress in cardiovascular, neurological, reproductive and metabolic diseases, and the knowledge gaps are also discussed. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu. Published by Elsevier B.V.

  19. Response to stress in Drosophila is mediated by gender, age and stress paradigm.

    Science.gov (United States)

    Neckameyer, Wendi S; Nieto-Romero, Andres R

    2015-01-01

    All living organisms must maintain equilibrium in response to internal and external challenges within their environment. Changes in neural plasticity (alterations in neuronal populations, dendritic remodeling, and synaptic turnover) are critical components of the homeostatic response to stress, which has been strongly implicated in the onset of affective disorders. However, stress is differentially perceived depending on the type of stress and its context, as well as genetic background, age and sex; therefore, an individual's maintenance of neuronal homeostasis must differ depending upon these variables. We established Drosophila as a model to analyze homeostatic responses to stress. Sexually immature and mature females and males from an isogenic wild-type strain raised under controlled environmental conditions were exposed to four reproducible and high-throughput translatable stressors to facilitate the analysis of a large number of animals for direct comparisons. These animals were assessed in an open-field arena, in a light-dark box, and in a forced swim test, as well as for sensitivity to the sedative effects of ethanol. These studies establish that immature and mature females and males represent behaviorally distinct populations under control conditions as well as after exposure to different stressors. Therefore, the neural substrates mediating the stress response must be differentially expressed depending upon the hormonal status of the brain. In addition, an adaptive response to a given stressor in one paradigm was not predictive for outcomes in other paradigms.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Physiological responses of genotypes soybean to simulated drought stress

    Directory of Open Access Journals (Sweden)

    Eleonóra Krivosudská

    2016-12-01

    Full Text Available The objective of this research was to investigate possible genetic variation in the sensitivity of soybean cultivars for nitrogen fixation rates in response to soil drying. The work confirmed that the selected physiological characteristics (RWC, osmotic potential, stress index and created nodules on roots are good evaluating parameters for the determination of water stress in plant. In the floricultural year 2014 an experiment with four genetic resources of soybean was launched. Sowing of Maverick (USA, Drina (HRV, Nigra (SVK and Polanka (CZK genotypes was carried out in the containers of 15 l capacity. This stress had a negative impact on the physiological parameters. By comparing the RWC values, the decrease was more significant at the end of dehydration, which was monitored in Maverick and Drina genotypes using the Nitrazon inoculants and water stress effect. Inoculated stressed Nigra and Polanka genotypes have kept higher water content till the end of dehydration period. Also the proline accumulation was monitored during the water stress, whilst higher content of free proline reached of Maverick. More remarkable decrease of osmotic potential was again registered in a foreign Drina and Maverick genotypes in the inoculated variations. Nigra and Polanka genotypes responses not so significant in the given conditions.

  2. Drought Stress Responses of Sunflower Germplasm Developed after Wide Hybridization

    Directory of Open Access Journals (Sweden)

    Roumiana Dimova Vassilevska-Ivanova

    2016-10-01

    Full Text Available Response of sunflower germplasms viz. cultivated sunflower H. annuus and two breeding lines H. annuus x T. rotundifolia and H. annuus x V. encelioides developed after wide hybridization were used for identification of drought tolerant sunflower genotypes at the seedling growth stage. Three water stress levels of zero (control, -0.4, and -0.8 MPa were developed using polyethyleneglycol-6000 (PEG-6000. Physiological and biochemical stress determining parameters such as root and shoots length, fresh weight, antioxidant enzyme activities (superoxide dismutase (SOD, catalase (CAT, guaiacol peroxidase (GPO, ascorbate peroxidase (APX and antioxidant metabolite content (total antioxidant capacity, total phenols and total flavonoids content were compared between seedlings of all three genotypes. Results revealed that sunflower genotypes have similar responses at two osmotic potentials for shoot and root length and fresh weight. The data also showed that drought stresss could induce oxidative stress, as indicated by the increase level of ascorbate peroxidase and guaiacol peroxidase at -04 MPa in H. annuus cv 1114. Although the activity of ascorbate peroxidase and guaiacol peroxidase was differentially influenced by drought, the changes of antioxidant enzyme activities such as catalase, superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase subjected to drought stress follow a similar pattern in both breeding lines, indicating that similar defense systems might be involved in the oxidative stress injury in sunflowers. Increase in content of phenols and flavonoids were detected for all three genotypes under stress, which showed that these were major antioxidant metabolites in scavenging cellular H2O2.

  3. Cortisol stress response in post-traumatic stress disorder, panic disorder, and major depressive disorder patients.

    Science.gov (United States)

    Wichmann, Susann; Kirschbaum, Clemens; Böhme, Carsten; Petrowski, Katja

    2017-09-01

    Previous research has focussed extensively on the distinction of HPA-axis functioning between patient groups and healthy volunteers, with relatively little emphasis on a direct comparison of patient groups. The current study's aim was to analyse differences in the cortisol stress response as a function of primary diagnosis of panic disorder (PD), post-traumatic stress disorder (PTSD), and major depressive disorder (MDD). A total of n=30 PD (mean age±SD: 36.07±12.56), n=23 PTSD (41.22±10.17), n=18 MDD patients (39.00±14.93) and n=47 healthy control (HC) individuals (35.51±13.15) participated in this study. All the study participants were female. The Trier Social Stress Test (TSST) was used for reliable laboratory stress induction. Blood sampling accompanied the TSST for cortisol and ACTH assessment. Panic-related, PTSD-specific questionnaires and the Beck Depression Inventory II were handed out for the characterisation of the study groups. Repeated measure ANCOVAs were conducted to test for main effects of time or group and for interaction effects. Regression analyses were conducted to take comorbid depression into account. 26.7% of the PD patients, 43.5% of the PTSD patients, 72.2% of the MDD patients and 80.6% of the HC participants showed a cortisol stress response upon the TSST. ANCOVA revealed a cortisol hypo-responsiveness both in PD and PTSD patients, while no significant group differences were seen in the ACTH concentrations. Additional analyses showed no impact of comorbid depressiveness on the cortisol stress response. MDD patients did not differ in the hormonal stress response neither compared to the HC participants nor to the PD and PTSD patients. Our main findings provide evidence of a dissociation between the cortisol and ACTH concentrations in response to the TSST in PTSD and in PD patients, independent of comorbid depression. Our results further support overall research findings of a cortisol hypo-responsiveness in PD patients. A hypo-response

  4. Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

    International Nuclear Information System (INIS)

    Christen, Verena; Capelle, Martinus; Fent, Karl

    2013-01-01

    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

  6. Suppressing Sorbitol Synthesis Substantially Alters the Global Expression Profile of Stress Response Genes in Apple (Malus domestica) Leaves.

    Science.gov (United States)

    Wu, Ting; Wang, Yi; Zheng, Yi; Fei, Zhangjun; Dandekar, Abhaya M; Xu, Kenong; Han, Zhenhai; Cheng, Lailiang

    2015-09-01

    Sorbitol is a major product of photosynthesis in apple (Malus domestica) that is involved in carbohydrate metabolism and stress tolerance. However, little is known about how the global transcript levels in apple leaves respond to decreased sorbitol synthesis. In this study we used RNA sequencing (RNA-seq) profiling to characterize the transcriptome of leaves from transgenic lines of the apple cultivar 'Greensleeves' exhibiting suppressed expression of aldose-6-phosphate reductase (A6PR) to gain insights into sorbitol function and the consequences of decreased sorbitol synthesis on gene expression. We observed that, although the leaves of the low sorbitol transgenic lines accumulate higher levels of various primary metabolites, only very limited changes were found in the levels of transcripts associated with primary metabolism. We suggest that this is indicative of post-transcriptional and/or post-translational regulation of primary metabolite accumulation and central carbon metabolism. However, we identified significantly enriched gene ontology terms belonging to the 'stress related process' category in the antisense lines (P-value sorbitol plays a role in the responses of apple trees to abiotic and biotic stresses. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

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

    Directory of Open Access Journals (Sweden)

    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. Patterns of Sympathetic Responses Induced by Different Stress Tasks

    Science.gov (United States)

    Fechir, M; Schlereth, T; Purat, T; Kritzmann, S; Geber, C; Eberle, T; Gamer, M; Birklein, F

    2008-01-01

    Stress tasks are used to induce sympathetic nervous system (SNS) arousal. However, the efficacy and the patterns of SNS activation have not been systematically compared between different tasks. Therefore, we analyzed SNS activation during the following stress tasks: Presentation of negative, positive, and – as a control – neutral affective pictures, Color-Word interference test (CWT), mental arithmetic under time limit, singing a song aloud, and giving a spontaneous talk. We examined 11 healthy subjects and recorded the following SNS parameters: Activation of emotional sweating by quantitative sudometry, skin vasoconstriction by laser-Doppler flowmetry, heart rate by ECG, blood pressure by determination of pulse wave transit time (PWTT), and electromyographic (EMG) activity of the trapezius muscle. Moreover, subjective stress ratings were acquired for each task using a visual analog scale. All tasks were felt significantly stressful when compared to viewing neutral pictures. However, SNS activation was not reliable: Affective pictures did not induce a significant SNS response; singing, giving a talk and mental arithmetic selectively increased heart rate and emotional sweating. Only the CWT globally activated the SNS. Regarding all tasks, induction of emotional sweating, increase of heart rate and blood pressure significantly correlated with subjective stress ratings, in contrast to EMG and skin vasoconstriction. Our results show that the activation of the SNS widely varies depending on the stress task. Different stress tasks differently activate the SNS, which is an important finding when considering sympathetic reactions - in clinical situations and in research. PMID:19018304

  9. Genome-wide association analysis reveals distinct genetic architectures for single and combined stress responses in Arabidopsis thaliana

    NARCIS (Netherlands)

    Davila Olivas, Nelson H.; Kruijer, Willem; Gort, Gerrit; Wijnen, Cris L.; Loon, van Joop J.A.; Dicke, Marcel

    2017-01-01

    Plants are commonly exposed to abiotic and biotic stresses. We used 350 Arabidopsis thaliana accessions grown under controlled conditions. We employed genome-wide association analysis to investigate the genetic architecture and underlying loci involved in genetic variation in resistance to: two

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

    Science.gov (United States)

    Lloyd, Richard E

    2016-03-30

    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.

  11. Eye surface temperature detects stress response in budgerigars (Melopsittacus undulatus).

    Science.gov (United States)

    Ikkatai, Yuko; Watanabe, Shigeru

    2015-08-05

    Previous studies have suggested that stressors not only increase body core temperature but also body surface temperature in many animals. However, it remains unclear whether surface temperature could be used as an alternative to directly measure body core temperature, particularly in birds. We investigated whether surface temperature is perceived as a stress response in budgerigars. Budgerigars have been used as popular animal models to investigate various neural mechanisms such as visual perception, vocal learning, and imitation. Developing a new technique to understand the basic physiological mechanism would help neuroscience researchers. First, we found that cloacal temperature correlated with eye surface temperature. Second, eye surface temperature increased after handling stress. Our findings suggest that eye surface temperature is closely related to cloacal temperature and that the stress response can be measured by eye surface temperature in budgerigars.

  12. [Regulation of heat shock gene expression in response to stress].

    Science.gov (United States)

    Garbuz, D G

    2017-01-01

    Heat shock (HS) genes, or stress genes, code for a number of proteins that collectively form the most ancient and universal stress defense system. The system determines the cell capability of adaptation to various adverse factors and performs a variety of auxiliary functions in normal physiological conditions. Common stress factors, such as higher temperatures, hypoxia, heavy metals, and others, suppress transcription and translation for the majority of genes, while HS genes are upregulated. Transcription of HS genes is controlled by transcription factors of the HS factor (HSF) family. Certain HSFs are activated on exposure to higher temperatures or other adverse factors to ensure stress-induced HS gene expression, while other HSFs are specifically activated at particular developmental stages. The regulation of the main mammalian stress-inducible factor HSF1 and Drosophila melanogaster HSF includes many components, such as a variety of early warning signals indicative of abnormal cell activity (e.g., increases in intracellular ceramide, cytosolic calcium ions, or partly denatured proteins); protein kinases, which phosphorylate HSFs at various Ser residues; acetyltransferases; and regulatory proteins, such as SUMO and HSBP1. Transcription factors other than HSFs are also involved in activating HS gene transcription; the set includes D. melanogaster GAF, mammalian Sp1 and NF-Y, and other factors. Transcription of several stress genes coding for molecular chaperones of the glucose-regulated protein (GRP) family is predominantly regulated by another stress-detecting system, which is known as the unfolded protein response (UPR) system and is activated in response to massive protein misfolding in the endoplasmic reticulum and mitochondrial matrix. A translational fine tuning of HS protein expression occurs via changing the phosphorylation status of several proteins involved in translation initiation. In addition, specific signal sequences in the 5'-UTRs of some HS

  13. Nitric oxide is involved in light-specific responses of tomato during germination under normal and osmotic stress conditions.

    Science.gov (United States)

    Piterková, Jana; Luhová, Lenka; Hofman, Jakub; Turecková, Veronika; Novák, Ondrej; Petrivalsky, Marek; Fellner, Martin

    2012-09-01

    Nitric oxide (NO) is involved in the signalling and regulation of plant growth and development and responses to biotic and abiotic stresses. The photoperiod-sensitive mutant 7B-1 in tomato (Solanum lycopersicum) showing abscisic acid (ABA) overproduction and blue light (BL)-specific tolerance to osmotic stress represents a valuable model to study the interaction between light, hormones and stress signalling. The role of NO as a regulator of seed germination and ABA-dependent responses to osmotic stress was explored in wild-type and 7B-1 tomato under white light (WL) and BL. Germination data were obtained from the incubation of seeds on germinating media of different composition. Histochemical analysis of NO production in germinating seeds was performed by fluorescence microscopy using a cell-permeable NO probe, and endogenous ABA was analysed by mass spectrometry. The NO donor S-nitrosoglutathione stimulated seed germination, whereas the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) had an inhibitory effect. Under WL in both genotypes, PTIO strongly suppressed germination stimulated by fluridone, an ABA inhibitor. The stimulatory effect of the NO donor was also observed under osmotic stress for 7B-1 seeds under WL and BL. Seed germination inhibited by osmotic stress was restored by fluridone under WL, but less so under BL, in both genotypes. This effect of fluridone was further modulated by the NO donor and NO scavenger, but only to a minor extent. Fluorescence microscopy using the cell-permeable NO probe DAF-FM DA (4-amino-5-methylamino-2',7'-difluorofluorescein diacetate) revealed a higher level of NO in stressed 7B-1 compared with wild-type seeds. As well as defective BL signalling, the differential NO-dependent responses of the 7B-1 mutant are probably associated with its high endogenous ABA concentration and related impact on hormonal cross-talk in germinating seeds. These data confirm that light-controlled seed germination and

  14. Biotic elements of NPP techno-ecosystem

    International Nuclear Information System (INIS)

    Protasov, A.A.; Silaeva, A.A.

    2013-01-01

    Specific features of biotic elements in the NPP techno-ecosystems were considered and compared with natural ecosystems. Relationships between biotic communities and environmental factors that are specific to the techno-ecosystems were discussed, and the problems of limitation of biological hindrances in operation of equipment, principles of hydrobiological and environmental monitoring were considered.

  15. CENTRAL AMYGDALOID INVOLVEMENT IN NEUROENDOCRINE CORRELATES OF CONDITIONED STRESS RESPONSES

    NARCIS (Netherlands)

    ROOZENDAAL, B; KOOLHAAS, JM; BOHUS, B

    The purpose of this study was to examine the effects of bilateral electrolytic lesions of the central nucleus of the amygdala (CEA) in comparison with sham lesions on neuroendocrine responses during conditioned emotional stress in male Wistar rats. Lesions in the CEA, made either before or after the

  16. Physiological response of heat stressed broiler chickens to ...

    African Journals Online (AJOL)

    Effect of supplementing the drinking water of broilers reared under natural heat stress with ammonium chloride (NH4Cl), sodium bicarbonate (NaHCO3), calcium chloride (CaCl2) and ascorbic acid (AA) on physiological response was investigated. A 200, one-day Arbor acre chicks were randomly allotted to five treatments in ...

  17. Oxidative stress response pathways: Fission yeast as archetype

    DEFF Research Database (Denmark)

    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...

  18. Physiological responses of food animals to road transportation stress

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-29

    Dec 29, 2009 ... transportation are numerous and the responses of the animal to them are complex, non-specific and ..... at 3 h after a 6 h journey in male Japanese goats. During ..... animals are subjected to concomitant action of transport- tation and heat stress .... those measured in moving vehicles (Warriss et al., 1993).

  19. Variability salt stress response analysis of Tunisian natural ...

    African Journals Online (AJOL)

    We evaluated the responses to salt stress of 106 Medicago truncatula lines from 11 Tunisian natural populations collected from areas that varied in soil composition, salinity and water availability. Five references lines were also included in this study. Plants were cultivated in two treatments (0 and 50 mM of NaCl) during a ...

  20. Long-term salt stress responsive growth, carbohydrate metabolism ...

    African Journals Online (AJOL)

    We investigated the long-term responses of tobacco tissues to salt stress, with a particular interest for growth parameters, proline (Pro) accumulation, and carbohydrate metabolism. Exposure of 17-day-old tobacco plants to 0.2 M NaCl was followed by a higher decrease in dry matter in roots than shoots with a decrease of ...

  1. Differential response to water deficit stress in alfalfa ( Medicago ...

    African Journals Online (AJOL)

    The present study was fixed as objective to compare the response to water deficit (33% of field capacity, FC) stress of eight cultivars of Medicago sativa, originating from the Mediterranean basin. Comparison was performed on some key parameters such as growth, relative water content, leaf water potential, MDA tissue ...

  2. Modulation of the immune response by emotional stress

    NARCIS (Netherlands)

    Croiset, G; Heijnen, C J; Veldhuis, H D; de Wied, D; Ballieux, R E

    1987-01-01

    The influence of mild, emotional stress was investigated for its effect on the immune system by subjecting rats to the one-trial-learning passive avoidance test. The reactivity of the immune system was tested by determining the proliferative response after mitogenic stimulation in vitro as well as

  3. Association between neuroticism and amygdala responsivity emerges under stressful conditions

    NARCIS (Netherlands)

    Everaerd, Daphne; Klumpers, Floris; van Wingen, Guido; Tendolkar, Indira; Fernández, Guillén

    2015-01-01

    Increased amygdala reactivity in response to salient stimuli is seen in patients with affective disorders, in healthy subjects at risk for these disorders, and in stressed individuals, making it a prime target for mechanistic studies into the pathophysiology of affective disorders. However, whereas

  4. Carica Papaya Seed Extract Enhances Cellular Response to Stress ...

    African Journals Online (AJOL)

    Therefore, the present study was carried out to investigate the role of Carica papaya seed (CPS) extract that contains, Benzyl Isothiocyanates, one of the inducers of phase II enzymes in the regulation of cellular stress. The cellular responses were observed in U937 cells (human monocyte/macrophage cell line) at the ...

  5. Physiological and biochemical responses to low temperature stress ...

    African Journals Online (AJOL)

    Cuttings of three hybrid clones of P. ussuriensis × P. deltoides were exposed to different low temperatures (cold and freezing) for 24 h, or consecutive low temperatures (5°C, 0 to 120 h), to determine physiological and biochemical responses to cold stress in these woody plants. Soluble sugar and protein contents increased ...

  6. Cyclooxygenase inhibitors and the exercise-induced stress response

    African Journals Online (AJOL)

    steroidal anti-inflammatory drug (NSAID) naproxen, and of the coxib, rofecoxib, on the exercise-induced stress response. Design. Eight subjects (age 20.9 ± 1.1 years, weight 70.4 ± 3.9 kg, height 170.9 ± 6.7 cm, body surface area 1.82 ± 0.09 m2, ...

  7. Flow stress asymmetry and cyclic stress--strain response in a BCC Ti--V alloy

    International Nuclear Information System (INIS)

    Koss, D.A.; Wojcik, C.C.

    1976-01-01

    The cyclic stress-strain response of relatively stable bcc β-phase Ti--40 percent V alloy single crystals was studied. Flow stress asymmetry found in the alloy is attributed to the fact that screw dislocations, when gliding on a (211) plane, are more mobile in the twinning direction than in the antitwinning direction. Thus the flow stress of the crystal is greater when it is sheared in the antitwinning direction than in the twinning direction (the latter case results when crystals of the 100 orientation are stressed in tension and those of the 110 orientation are stressed in compression). Such behavior can be a result of the core of a screw dislocation being asymmetric under stress which causes the flow stress asymmetry observed. It should be noted that screw dislocations dominate the low temperature deformation structure of Ti-40V, which strongly suggests deformation is controlled by screw dislocation motion. The observation in Mo that the microyield stress is independent of crystal orientation could be a result of edge dislocation motion controlling microyield in that instance and this observation would not be inconsistent with screw dislocation motion controlling the macroscopic (epsilon/sub p/ greater than 0.05 percent) deformation measured here

  8. Moving through the Stressed Genome: Emerging Regulatory Roles for Transposons in Plant Stress Response.

    Science.gov (United States)

    Negi, Pooja; Rai, Archana N; Suprasanna, Penna

    2016-01-01

    The recognition of a positive correlation between organism genome size with its transposable element (TE) content, represents a key discovery of the field of genome biology. Considerable evidence accumulated since then suggests the involvement of TEs in genome structure, evolution and function. The global genome reorganization brought about by transposon activity might play an adaptive/regulatory role in the host response to environmental challenges, reminiscent of McClintock's original 'Controlling Element' hypothesis. This regulatory aspect of TEs is also garnering support in light of the recent evidences, which project TEs as "distributed genomic control modules." According to this view, TEs are capable of actively reprogramming host genes circuits and ultimately fine-tuning the host response to specific environmental stimuli. Moreover, the stress-induced changes in epigenetic status of TE activity may allow TEs to propagate their stress responsive elements to host genes; the resulting genome fluidity can permit phenotypic plasticity and adaptation to stress. Given their predominating presence in the plant genomes, nested organization in the genic regions and potential regulatory role in stress response, TEs hold unexplored potential for crop improvement programs. This review intends to present the current information about the roles played by TEs in plant genome organization, evolution, and function and highlight the regulatory mechanisms in plant stress responses. We will also briefly discuss the connection between TE activity, host epigenetic response and phenotypic plasticity as a critical link for traversing the translational bridge from a purely basic study of TEs, to the applied field of stress adaptation and crop improvement.

  9. Moving through the Stressed Genome: Emerging Regulatory Roles for Transposons in Plant Stress Response

    Science.gov (United States)

    Negi, Pooja; Rai, Archana N.; Suprasanna, Penna

    2016-01-01

    The recognition of a positive correlation between organism genome size with its transposable element (TE) content, represents a key discovery of the field of genome biology. Considerable evidence accumulated since then suggests the involvement of TEs in genome structure, evolution and function. The global genome reorganization brought about by transposon activity might play an adaptive/regulatory role in the host response to environmental challenges, reminiscent of McClintock's original ‘Controlling Element’ hypothesis. This regulatory aspect of TEs is also garnering support in light of the recent evidences, which project TEs as “distributed genomic control modules.” According to this view, TEs are capable of actively reprogramming host genes circuits and ultimately fine-tuning the host response to specific environmental stimuli. Moreover, the stress-induced changes in epigenetic status of TE activity may allow TEs to propagate their stress responsive elements to host genes; the resulting genome fluidity can permit phenotypic plasticity and adaptation to stress. Given their predominating presence in the plant genomes, nested organization in the genic regions and potential regulatory role in stress response, TEs hold unexplored potential for crop improvement programs. This review intends to present the current information about the roles played by TEs in plant genome organization, evolution, and function and highlight the regulatory mechanisms in plant stress responses. We will also briefly discuss the connection between TE activity, host epigenetic response and phenotypic plasticity as a critical link for traversing the translational bridge from a purely basic study of TEs, to the applied field of stress adaptation and crop improvement. PMID:27777577

  10. Molecular identification and characterization of the pyruvate decarboxylase gene family associated with latex regeneration and stress response in rubber tree.

    Science.gov (United States)

    Long, Xiangyu; He, Bin; Wang, Chuang; Fang, Yongjun; Qi, Jiyan; Tang, Chaorong

    2015-02-01

    In plants, ethanolic fermentation occurs not only under anaerobic conditions but also under aerobic conditions, and involves carbohydrate and energy metabolism. Pyruvate decarboxylase (PDC) is the first and the key enzyme of ethanolic fermentation, which branches off the main glycolytic pathway at pyruvate. Here, four PDC genes were isolated and identified in a rubber tree, and the protein sequences they encode are very similar. The expression patterns of HbPDC4 correlated well with tapping-simulated rubber productivity in virgin rubber trees, indicating it plays an important role in regulating glycometabolism during latex regeneration. HbPDC1, HbPDC2 and HbPDC3 had striking expressional responses in leaves and bark to drought, low temperature and high temperature stresses, indicating that the HbPDC genes are involve in self-protection and defense in response to various abiotic and biotic stresses during rubber tree growth and development. To understand ethanolic fermentation in rubber trees, it will be necessary to perform an in-depth study of the regulatory pathways controlling the HbPDCs in the future. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

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

    OpenAIRE

    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. Early life adversity influences stress response association with smoking relapse.

    Science.gov (United States)

    al'Absi, Mustafa; Lemieux, Andrine; Westra, Ruth; Allen, Sharon

    2017-11-01

    We examined the hypothesis that stress-related blunting of cortisol in smokers is particularly pronounced in those with a history of severe life adversity. The two aims of this study were first to examine hormonal, craving, and withdrawal symptoms during ad libitum smoking and after the first 24 h of abstinence in smokers who experienced high or low levels of adversity. Second, we sought to examine the relationship between adversity and hypothalamic-pituitary-adrenal (HPA) hormones to predict relapse during the first month of a smoking cessation attempt. Hormonal and self-report measures were collected from 103 smokers (49 women) during ad libitum smoking and after the first 24 h of abstinence. HPA hormones were measured during baseline rest and in response to acute stress in both conditions. All smokers were interested in smoking cessation, and we prospectively used stress response measures to predict relapse during the first 4 weeks of the smoking cessation attempt. The results showed that high adversity was associated with higher distress and smoking withdrawal symptoms. High level of early life adversity was associated with elevated HPA activity, which was found in both salivary and plasma cortisol. Enhanced adrenocorticotropic hormone (ACTH) stress response was evident in high-adversity but not in low-adversity relapsers. This study demonstrated that early life adversity is associated with stress-related HPA responses. The study also demonstrated that, among smokers who experienced a high level of life adversity, heightened ACTH and cortisol responses were linked with increased risk for smoking relapse.

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

    Directory of Open Access Journals (Sweden)

    Mohd Hashim Intan Hashimah

    2015-01-01

    Full Text Available 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. They had fairly low stress on issues related to romantic partner and romantic relationships. They however reported extensive roles and responsibilities. Single mothers reported feeling responsible across various domains of life including for their own health and well-being and also for the health and wellbeing of their family and friends. They reported high level of coping and particularly oriented towards solving the problems. They also reported general satisfaction over life. Correlation analysis indicated significant positive relationships between roles and responsibilities and life satisfaction and coping in which coping was associated with higher level of roles and responsibilities and life satisfaction. There was also a negative correlation between stress and life satisfaction in which more stress was associated with lower life satisfaction. Findings indicated a substantial nurturing role of single mothers and provided important policy and practice implications that highlights the important to study and continuously improve quality of life for these women. Finally, this study highlights the important to continuously study and support, important but marginalized groups in society such as single mothers.

  14. Scaled biotic disruption during early Eocene global warming events

    Directory of Open Access Journals (Sweden)

    S. J. Gibbs

    2012-11-01

    Full Text Available Late Paleocene and early Eocene hyperthermals are transient warming events associated with massive perturbations of the global carbon cycle, and are considered partial analogues for current anthropogenic climate change. Because the magnitude of carbon release varied between the events, they are natural experiments ideal for exploring the relationship between carbon cycle perturbations, climate change and biotic response. Here we quantify marine biotic variability through three million years of the early Eocene that include five hyperthermals, utilizing a method that allows us to integrate the records of different plankton groups through scenarios ranging from background to major extinction events. Our long time-series calcareous nannoplankton record indicates a scaling of biotic disruption to climate change associated with the amount of carbon released during the various hyperthermals. Critically, only the three largest hyperthermals, the Paleocene–Eocene Thermal Maximum (PETM, Eocene Thermal Maximum 2 (ETM2 and the I1 event, show above-background variance, suggesting that the magnitude of carbon input and associated climate change needs to surpass a threshold value to cause significant biotic disruption.

  15. Yeast signaling pathways in the oxidative stress response

    Energy Technology Data Exchange (ETDEWEB)

    Ikner, Aminah [Section of Microbiology, Division of Biological Sciences, University of California, Davis, CA 95616 (United States); Shiozaki, Kazuhiro [Section of Microbiology, Division of Biological Sciences, University of California, Davis, CA 95616 (United States)]. E-mail: kshiozaki@ucdavis.edu

    2005-01-06

    Oxidative stress that generates the reactive oxygen species (ROS) is one of the major causes of DNA damage and mutations. The 'DNA damage checkpoint' that arrests cell cycle and repairs damaged DNA has been a focus of recent studies, and the genetically amenable model systems provided by yeasts have been playing a leading role in the eukaryotic checkpoint research. However, means to eliminate ROS are likely to be as important as the DNA repair mechanisms in order to suppress mutations in the chromosomal DNA, and yeasts also serve as excellent models to understand how eukaryotes combat oxidative stress. In this article, we present an overview of the signaling pathways that sense oxidative stress and induce expression of various anti-oxidant genes in the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe and the pathogenic yeast Candida albicans. Three conserved signaling modules have been identified in the oxidative stress response of these diverse yeast species: the stress-responsive MAP kinase cascade, the multistep phosphorelay and the AP-1-like transcription factor. The structure and function of these signaling modules are discussed.

  16. Yeast signaling pathways in the oxidative stress response

    International Nuclear Information System (INIS)

    Ikner, Aminah; Shiozaki, Kazuhiro

    2005-01-01

    Oxidative stress that generates the reactive oxygen species (ROS) is one of the major causes of DNA damage and mutations. The 'DNA damage checkpoint' that arrests cell cycle and repairs damaged DNA has been a focus of recent studies, and the genetically amenable model systems provided by yeasts have been playing a leading role in the eukaryotic checkpoint research. However, means to eliminate ROS are likely to be as important as the DNA repair mechanisms in order to suppress mutations in the chromosomal DNA, and yeasts also serve as excellent models to understand how eukaryotes combat oxidative stress. In this article, we present an overview of the signaling pathways that sense oxidative stress and induce expression of various anti-oxidant genes in the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe and the pathogenic yeast Candida albicans. Three conserved signaling modules have been identified in the oxidative stress response of these diverse yeast species: the stress-responsive MAP kinase cascade, the multistep phosphorelay and the AP-1-like transcription factor. The structure and function of these signaling modules are discussed

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

    Science.gov (United States)

    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…

  18. DNA methylation and transcriptomic changes in response to different lights and stresses in 7B-1 male-sterile tomato.

    Directory of Open Access Journals (Sweden)

    Vahid Omidvar

    Full Text Available We reported earlier that 7B-1 mutant in tomato (Solanum lycopersicum L., cv. Rutgers, an ABA overproducer, is defective in blue light (B signaling leading to B-specific resistance to abiotic and biotic stresses. Using a methylation-sensitive amplified polymorphism (MSAP assay, a number of genes were identified, which were differentially methylated between 7B-1 and its wild type (WT seedlings in white (W, blue (B, red (R lights and dark (D or in response to exogenous ABA and mannitol-induced stresses. The genomic methylation level was almost similar in different lights between 7B-1 and WT seedlings, while significant differences were observed in response to stresses in D, but not B. Using a cDNA-AFLP assay, several transcripts were identified, which were differentially regulated between 7B-1 and WT by B or D or in response to stresses. Blue light receptors cryptochrome 1 and 2 (CRY1 and CRY2 and phototropin 1 and 2 (PHOT1 and PHOT2 were not affected by the 7B-1 mutation at the transcriptional level, instead the mutation had likely affected downstream components of the light signaling pathway. 5-azacytidine (5-azaC induced DNA hypomethylation, inhibited stem elongation and differentially regulated the expression of a number of genes in 7B-1. In addition, it was shown that mir167 and mir390 were tightly linked to auxin signaling pathway in 5-azaC-treated 7B-1 seedlings via the regulation of auxin-response factor (ARF transcripts. Our data showed that DNA methylation remodeling is an active epigenetic response to different lights and stresses in 7B-1 and WT, and highlighted the differences in epigenetic and transcriptional regulation of light and stress responses between 7B-1 and WT. Furthermore, it shed lights on the crosstalk between DNA hypomethylation and miRNA regulation of ARFs expression. This information could also be used as a benchmark for future studies of male-sterility in other crops.

  19. Aging augments renal vasoconstrictor response to orthostatic stress in humans.

    Science.gov (United States)

    Clark, Christine M; Monahan, Kevin D; Drew, Rachel C

    2015-12-15

    The ability of the human body to maintain arterial blood pressure (BP) during orthostatic stress is determined by several reflex neural mechanisms. Renal vasoconstriction progressively increases during graded elevations in lower body negative pressure (LBNP). This sympathetically mediated response redistributes blood flow to the systemic circulation to maintain BP. However, how healthy aging affects the renal vasoconstrictor response to LBNP is unknown. Therefore, 10 young (25 ± 1 yr; means ± SE) and 10 older (66 ± 2 yr) subjects underwent graded LBNP (-15 and -30 mmHg) while beat-to-beat renal blood flow velocity (RBFV; Doppler ultrasound), arterial BP (Finometer), and heart rate (HR; electrocardiogram) were recorded. Renal vascular resistance (RVR), an index of renal vasoconstriction, was calculated as mean BP/RBFV. All baseline cardiovascular variables were similar between groups, except diastolic BP was higher in older subjects (P aging augments the renal vasoconstrictor response to orthostatic stress in humans. Copyright © 2015 the American Physiological Society.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. The relationship between personality and the response to acute psychological stress.

    Science.gov (United States)

    Xin, Yuanyuan; Wu, Jianhui; Yao, Zhuxi; Guan, Qing; Aleman, André; Luo, Yuejia

    2017-12-04

    The present study examined the relationship between personality traits and the response to acute psychological stress induced by a standardized laboratory stress induction procedure (the Trier Social Stress Test, TSST). The stress response was measured with a combination of cardiovascular reactivity, hypothalamic-pituitary-adrenal axis reactivity, and subjective affect (including positive affect, negative affect and subjective controllability) in healthy individuals. The Generalized Estimating Equations (GEE) approach was applied to account for the relationship between personality traits and stress responses. Results suggested that higher neuroticism predicted lower heart rate stress reactivity, lower cortisol stress response, more decline of positive affect and lower subjective controllability. Individuals higher in extraversion showed smaller cortisol activation to stress and less increase of negative affect. In addition, higher openness score was associated with lower cortisol stress response. These findings elucidate that neuroticism, extraversion and openness are important variables associated with the stress response and different dimensions of personality trait are associated with different aspects of the stress response.

  2. The Transcriptomic Responses of Pinus massoniana to Drought Stress

    Directory of Open Access Journals (Sweden)

    Mingfeng Du

    2018-06-01

    Full Text Available Masson pine (Pinus massoniana is a major fast-growing timber species planted in southern China, a region of seasonal drought. Using a drought-tolerance genotype of Masson pine, we conducted large-scale transcriptome sequencing using Illumina technology. This work aimed to evaluate the transcriptomic responses of Masson pine to different levels of drought stress. First, 3397, 1695 and 1550 unigenes with differential expression were identified by comparing plants subjected to light, moderate or severe drought with control plants. Second, several gene ontology (GO categories (oxidation-reduction and metabolism and Kyoto Encyclopedia of Genes and Genomes (KEGG pathways (plant hormone signal transduction and metabolic pathways were enriched, indicating that the expression levels of some genes in these enriched GO terms and pathways were altered under drought stress. Third, several transcription factors (TFs associated with circadian rhythms (HY5 and LHY, signal transduction (ERF, and defense responses (WRKY were identified, and these TFs may play key roles in adapting to drought stress. Drought also caused significant changes in the expression of certain functional genes linked to osmotic adjustment (P5CS, abscisic acid (ABA responses (NCED, PYL, PP2C and SnRK, and reactive oxygen species (ROS scavenging (GPX, GST and GSR. These transcriptomic results provide insight into the molecular mechanisms of drought stress adaptation in Masson pine.

  3. Psychological stress during exercise: cardiorespiratory and hormonal responses.

    Science.gov (United States)

    Webb, Heather E; Weldy, Michael L; Fabianke-Kadue, Emily C; Orndorff, G R; Kamimori, Gary H; Acevedo, Edmund O

    2008-12-01

    The purpose of this study was to examine the cardiorespiratory (CR) and stress hormone responses to a combined physical and mental stress. Eight participants (VO2(max) = 41.24 +/- 6.20 ml kg(-1) min(-1)) completed two experimental conditions, a treatment condition including a 37 min ride at 60% of VO2(max) with participants responding to a computerized mental challenge dual stress condition (DSC) and a control condition of the same duration and intensity without the mental challenge exercise alone condition (EAC). Significant interactions across time were found for CR responses, with heart rate, ventilation, and respiration rate demonstrating higher increases in the DSC. Additionally, norepinephrine was significantly greater in the DSC at the end of the combined challenge. Furthermore, cortisol area-under-the-curve (AUC) was also significantly elevated during the DSC. These results demonstrate that a mental challenge during exercise can exacerbate the stress response, including the release of hormones that have been linked to negative health consequences (cardiovascular, metabolic, autoimmune illnesses).

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Electrical response of relaxing dielectrics compressed by arbitrary stress pulses

    International Nuclear Information System (INIS)

    Lysne, P.C.

    1983-01-01

    The theoretical problem of the electric response of biased dielectrics and piezoelectrics subjected to planar stress pulse loading is considered. The materials are taken to exhibit dielectric relaxation in the sense that changes in the polarization induced by electric fields do not occur instantaneously with changes in the fields. While this paper considers arbitrary stress pulse loading of the specimen, examples that are amenable to projectile impact techniques are considered in detail. They are shock reverberation, thin pulse, and ramp loading experiments. It is anticipated that these experiments will play a role in investigations of dielectric relaxation caused by shock induced damage in insulators

  6. Surgical stress response: does endoscopic surgery confer an advantage?

    DEFF Research Database (Denmark)

    Kehlet, H

    1999-01-01

    of postoperative pulmonary function and less hypoxemia with endoscopic operation. The slight modification of surgical stress responses by endoscopic surgery is in contrast to the common, though not universal, demonstration of less pain, shorter hospital stay, and less morbidity after endoscopic surgery...... operations where differences are more likely to be found. The clinical consequences of these findings in relation to all over surgical outcome remain to be defined, but effective pain treatment, stress reduction by other techniques, and provision of an active rehabilitation program with early mobilization...

  7. Transcriptomic analysis of salt stress responsive genes in Rhazya stricta.

    Directory of Open Access Journals (Sweden)

    Nahid H Hajrah

    Full Text Available Rhazya stricta is an evergreen shrub that is widely distributed across Western and South Asia, and like many other members of the Apocynaceae produces monoterpene indole alkaloids that have anti-cancer properties. This species is adapted to very harsh desert conditions making it an excellent system for studying tolerance to high temperatures and salinity. RNA-Seq analysis was performed on R. stricta exposed to severe salt stress (500 mM NaCl across four time intervals (0, 2, 12 and 24 h to examine mechanisms of salt tolerance. A large number of transcripts including genes encoding tetrapyrroles and pentatricopeptide repeat (PPR proteins were regulated only after 12 h of stress of seedlings grown in controlled greenhouse conditions. Mechanisms of salt tolerance in R. stricta may involve the upregulation of genes encoding chaperone protein Dnaj6, UDP-glucosyl transferase 85a2, protein transparent testa 12 and respiratory burst oxidase homolog protein b. Many of the highly-expressed genes act on protecting protein folding during salt stress and the production of flavonoids, key secondary metabolites in stress tolerance. Other regulated genes encode enzymes in the porphyrin and chlorophyll metabolic pathway with important roles during plant growth, photosynthesis, hormone signaling and abiotic responses. Heme biosynthesis in R. stricta leaves might add to the level of salt stress tolerance by maintaining appropriate levels of photosynthesis and normal plant growth as well as by the participation in reactive oxygen species (ROS production under stress. We speculate that the high expression levels of PPR genes may be dependent on expression levels of their targeted editing genes. Although the results of PPR gene family indicated regulation of a large number of transcripts under salt stress, PPR actions were independent of the salt stress because their RNA editing patterns were unchanged.

  8. Coping as a mediator of the relationship between stress mindset and psychological stress response: a pilot study

    Directory of Open Access Journals (Sweden)

    Horiuchi S

    2018-03-01

    Full Text Available Satoshi Horiuchi,1 Akira Tsuda,2 Shuntaro Aoki,3,4 Kenichiro Yoneda,5 Yusuke Sawaguchi6 1Faculty of Social Welfare, Iwate Prefectural University, Iwate, 2Department of Psychology, Kurume University, Fukuoka, 3Research Fellow of Japan Society for the Promotion of Science, Tokyo, 4Graduate School of Psychological Science, Health Sciences University of Hokkaido, Hokkaido, 5Graduate School of Psychology, Kurume University, Fukuoka, 6Graduate School of Social Welfare, Iwate Prefectural University, Iwate, Japan Background: Coping, the cognitive and behavioral effort required to manage the effects of stressors, is important in determining psychological stress responses (ie, the emotional, behavioral, and cognitive responses to stressors. Coping was classified into categories of emotional expression (eg, negative feelings and thoughts, emotional support seeking (eg, approaching loved ones to request encouragement, cognitive reinterpretation (eg, reframing a problem positively, and problem solving (eg, working to solve the problem. Stress mindset refers to the belief that stress has enhancing (stress-is-enhancing mindset or debilitating consequences (stress-is-debilitating mindset. This study examined whether coping mediated the relationship between stress mindset and psychological stress responses. Psychological stress responses were conceptualized as depression-anxiety, irritability-anger, and helplessness. The following two hypotheses were tested: 1 a stronger stress-is-enhancing mindset is associated with less frequent use of emotional expression, emotional support seeking, and problem solving, which in turn is associated with lower levels of depression-anxiety, irritability-anger, and helplessness; 2 a stronger stress-is-debilitating mindset is associated with more frequent use of these coping strategies, which in turn is associated with higher levels of these psychological stress responses. Materials and methods: The participants were 30 male and

  9. Comparative Analysis of WRKY Genes Potentially Involved in Salt Stress Responses in Triticum turgidum L. ssp. durum.

    Science.gov (United States)

    Yousfi, Fatma-Ezzahra; Makhloufi, Emna; Marande, William; Ghorbel, Abdel W; Bouzayen, Mondher; Bergès, Hélène

    2016-01-01

    WRKY transcription factors are involved in multiple aspects of plant growth, development and responses to biotic stresses. Although they have been found to play roles in regulating plant responses to environmental stresses, these roles still need to be explored, especially those pertaining to crops. Durum wheat is the second most widely produced cereal in the world. Complex, large and unsequenced genomes, in addition to a lack of genomic resources, hinder the molecular characterization of tolerance mechanisms. This paper describes the isolation and characterization of five TdWRKY genes from durum wheat ( Triticum turgidum L . ssp. durum ). A PCR-based screening of a T. turgidum BAC genomic library using primers within the conserved region of WRKY genes resulted in the isolation of five BAC clones. Following sequencing fully the five BACs, fine annotation through Triannot pipeline revealed 74.6% of the entire sequences as transposable elements and a 3.2% gene content with genes organized as islands within oceans of TEs. Each BAC clone harbored a TdWRKY gene. The study showed a very extensive conservation of genomic structure between TdWRKYs and their orthologs from Brachypodium, barley, and T. aestivum . The structural features of TdWRKY proteins suggested that they are novel members of the WRKY family in durum wheat. TdWRKY1/2/4, TdWRKY3, and TdWRKY5 belong to the group Ia, IIa, and IIc, respectively. Enrichment of cis -regulatory elements related to stress responses in the promoters of some TdWRKY genes indicated their potential roles in mediating plant responses to a wide variety of environmental stresses. TdWRKY genes displayed different expression patterns in response to salt stress that distinguishes two durum wheat genotypes with contrasting salt stress tolerance phenotypes. TdWRKY genes tended to react earlier with a down-regulation in sensitive genotype leaves and with an up-regulation in tolerant genotype leaves. The TdWRKY transcripts levels in roots

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

    Directory of Open Access Journals (Sweden)

    Gyoungju Nah

    Full Text Available 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.

  11. Allelopathic Responses of Rice Seedlings under Some Different Stresses

    Directory of Open Access Journals (Sweden)

    Tran Dang Khanh

    2018-05-01

    Full Text Available The objective of this study was to evaluate the allelopathic responses of rice seedlings under submergence stress at different temperatures (10, 25, 32, and 37 °C. The results showed that a wide range of allelopathic responses of rice seedlings depended on varieties and stress conditions, with temperature was being a key factor. It showed that the extracts of rice seedlings induced significant suppression on lettuce and radish seedling germination, but had negligible allelopathic effects on growth of barnyardgrass, whilst the emergence and growth of natural weeds was stimulated. In contrast, the root exudates of Koshihikari rice seedlings (K32 at 32 °C reduced the number of total weeds by ≈60.0% and the total dry weight of weeds by 93.0%; i.e., to a greater extent than other root exudates. Among the 13 identified phenolic acids, p-hydroxybenzoic, vanillic, syringic, sinapic and benzoic acids—at concentrations of 0.360, 0.045, 3.052, 1.309 and 5.543 μg/mL might be involved in allelopathic responses of K32, inhibiting the growth of barnyardgrass and natural weeds. Findings of the present study may provide useful information on allelopathic responses of rice under environmental stresses and thus further understand of the competitive relationships between rice and weeds under natural conditions.

  12. Deciphering hepatocellular responses to metabolic and oncogenic stress

    Directory of Open Access Journals (Sweden)

    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.

  13. Evasion of Apoptosis as a Cellular Stress Response in Cancer

    Directory of Open Access Journals (Sweden)

    Simone Fulda

    2010-01-01

    Full Text Available One of the hallmarks of human cancers is the intrinsic or acquired resistance to apoptosis. Evasion of apoptosis can be part of a cellular stress response to ensure the cell's survival upon exposure to stressful stimuli. Apoptosis resistance may contribute to carcinogenesis, tumor progression, and also treatment resistance, since most current anticancer therapies including chemotherapy as well as radio- and immunotherapies primarily act by activating cell death pathways including apoptosis in cancer cells. Hence, a better understanding of the molecular mechanisms regarding how cellular stress stimuli trigger antiapoptotic mechanisms and how this contributes to tumor resistance to apoptotic cell death is expected to provide the basis for a rational approach to overcome apoptosis resistance mechanisms in cancers.

  14. Stress response in female veterans: an allostatic perspective.

    Science.gov (United States)

    Groër, Maureen Wimberly; Burns, Candace

    2009-01-01

    Women serving in the military face many sources of stress, such as separation from home and family, sexual harassment and assault, and deployment to traumatic war zones. Some women are vulnerable to the effects of these stressors, resulting in deleterious mental and physical health outcomes. Understanding these risks through the theoretical model of allostasis can help identify those who will be most vulnerable and help healthcare providers prevent some negative outcomes and improve rehabilitation for some women when they return stateside. Women may be more likely than men to present with mental health problems such as posttraumatic stress disorder and depression after military service. They also may be at increased risk, based on their war-zone stress response, for disparate illness such as medically unexplained illness, cancer, and heart disease. The need for care for these women is expected to increase as more women are deployed to conflicts.

  15. The role of stress mindset in shaping cognitive, emotional, and physiological responses to challenging and threatening stress.

    Science.gov (United States)

    Crum, Alia J; Akinola, Modupe; Martin, Ashley; Fath, Sean

    2017-07-01

    Prior research suggests that altering situation-specific evaluations of stress as challenging versus threatening can improve responses to stress. The aim of the current study was to explore whether cognitive, physiological and affective stress responses can be altered independent of situation-specific evaluations by changing individuals' mindsets about the nature of stress in general. Using a 2 × 2 design, we experimentally manipulated stress mindset using multi-media film clips orienting participants (N = 113) to either the enhancing or debilitating nature of stress. We also manipulated challenge and threat evaluations by providing positive or negative feedback to participants during a social stress test. Results revealed that under both threat and challenge stress evaluations, a stress-is-enhancing mindset produced sharper increases in anabolic ("growth") hormones relative to a stress-is-debilitating mindset. Furthermore, when the stress was evaluated as a challenge, a stress-is-enhancing mindset produced sharper increases in positive affect, heightened attentional bias towards positive stimuli, and greater cognitive flexibility, whereas a stress-is-debilitating mindset produced worse cognitive and affective outcomes. These findings advance stress management theory and practice by demonstrating that a short manipulation designed to generate a stress-is-enhancing mindset can improve responses to both challenging and threatening stress.

  16. In response to community violence: coping strategies and involuntary stress responses among Latino adolescents.

    Science.gov (United States)

    Epstein-Ngo, Quyen; Maurizi, Laura K; Bregman, Allyson; Ceballo, Rosario

    2013-01-01

    Among poor, urban adolescents, high rates of community violence are a pressing public health concern. This study relies on a contextual framework of stress and coping to investigate how coping strategies and involuntary stress responses may both mediate and moderate the relation between exposure to community violence and psychological well-being. Our sample consists of 223 ninth grade Latino adolescents from poor, urban families. In response to community violence, these adolescents reported using an array of coping strategies as well as experiencing a number of involuntary stress responses; the most frequent coping responses were turning to religion and seeking social support. Hierarchical regression analyses demonstrated that involuntary stress responses mediated the relations between both witnessing or being victimized by violence and poorer psychological functioning, while coping strategies moderated these relations. These findings suggest that the negative psychological effects of exposure to community violence may, in part, be explained by involuntary stress responses, while religious-based coping may serve as a protective factor.

  17. Children's biological responsivity to acute stress predicts concurrent cognitive performance.

    Science.gov (United States)

    Roos, Leslie E; Beauchamp, Kathryn G; Giuliano, Ryan; Zalewski, Maureen; Kim, Hyoun K; Fisher, Philip A

    2018-04-10

    Although prior research has characterized stress system reactivity (i.e. hypothalamic-pituitary-adrenal axis, HPAA; autonomic nervous system, ANS) in children, it has yet to examine the extent to which biological reactivity predicts concurrent goal-directed behavior. Here, we employed a stressor paradigm that allowed concurrent assessment of both stress system reactivity and performance on a speeded-response task to investigate the links between biological reactivity and cognitive function under stress. We further investigated gender as a moderator given previous research suggesting that the ANS may be particularly predictive of behavior in males due to gender differences in socialization. In a sociodemographically diverse sample of young children (N = 58, M age = 5.38 yrs; 44% male), individual differences in sociodemographic covariates (age, household income), HPAA (i.e. cortisol), and ANS (i.e. respiratory sinus arrhythmia, RSA, indexing the parasympathetic branch; pre-ejection period, PEP, indexing the sympathetic branch) function were assessed as predictors of cognitive performance under stress. We hypothesized that higher income, older age, and greater cortisol reactivity would be associated with better performance overall, and flexible ANS responsivity (i.e. RSA withdrawal, PEP shortening) would be predictive of performance for males. Overall, females performed better than males. Two-group SEM analyses suggest that, for males, greater RSA withdrawal to the stressor was associated with better performance, while for females, older age, higher income, and greater cortisol reactivity were associated with better performance. Results highlight the relevance of stress system reactivity to cognitive performance under stress. Future research is needed to further elucidate for whom and in what situations biological reactivity predicts goal-directed behavior.

  18. Short-term spatial memory responses in aged Japanese quail selected for divergent adrenocortical stress responsiveness.

    Science.gov (United States)

    Suhr, C L; Schmidt, J B; Treese, S T; Satterlee, D G

    2010-04-01

    Stress-induced glucocorticoids can dampen learning and spatial memory via neuronal damage to the hippocampus. Cognition losses can be transient (associated with acute stress episodes) or permanent as in aged individuals who show chronic glucocorticoid-induced accelerated brain aging and neurodegeneration (dementia). Thus, chronic versus acute stress effects on spatial memory responses of quail selected for reduced (low stress, LS) or exaggerated (high stress, HS) plasma corticosterone (B) response to brief restraint were assessed. Aged food-motivated male LS and HS quail were tested for 10 min in a feed-baited 8-arm radial arm maze (RAM) 1) at 255 d of age (quail who had experienced lifelong management stressors but who were otherwise never intentionally stressed; that is, chronically stressed birds), 2) on the next day post-acute stressor treatment (5 min of restraint), and 3) on the next day without treatment (acute stress recovery). The RAM tests used the win-shift procedure in which visited arms were not rebaited. Radial arm maze performance was measured by determination of the total number of arm choices made, the number of correct entries made into baited arms out of the first 8 choices, the time required to make a choice, and the number of pellets eaten. Line effects (P LS), and number of pellets eaten (HS RAM testing nor its interaction with line further influenced these variables. Thus, although selection for divergent plasma B responsiveness to an acute stressor was found to be associated with severe impairment of spatial memory in aged male HS compared with LS quail, the observed spatial memory impairments (HS > LS) could not be further altered by acute stressor treatment. Line differences in cognition may reflect lifelong management-induced stress episodes that periodically produce higher plasma B responses in HS than LS quail, which underlie HS quail memory deficits, or other etiologies, or both.

  19. Gene Expression Dynamics Accompanying the Sponge Thermal Stress Response.

    Science.gov (United States)

    Guzman, Christine; Conaco, Cecilia

    2016-01-01

    Marine sponges are important members of coral reef ecosystems. Thus, their responses to changes in ocean chemistry and environmental conditions, particularly to higher seawater temperatures, will have potential impacts on the future of these reefs. To better understand the sponge thermal stress response, we investigated gene expression dynamics in the shallow water sponge, Haliclona tubifera (order Haplosclerida, class Demospongiae), subjected to elevated temperature. Using high-throughput transcriptome sequencing, we show that these conditions result in the activation of various processes that interact to maintain cellular homeostasis. Short-term thermal stress resulted in the induction of heat shock proteins, antioxidants, and genes involved in signal transduction and innate immunity pathways. Prolonged exposure to thermal stress affected the expression of genes involved in cellular damage repair, apoptosis, signaling and transcription. Interestingly, exposure to sublethal temperatures may improve the ability of the sponge to mitigate cellular damage under more extreme stress conditions. These insights into the potential mechanisms of adaptation and resilience of sponges contribute to a better understanding of sponge conservation status and the prediction of ecosystem trajectories under future climate conditions.

  20. Herboxidiene triggers splicing repression and abiotic stress responses in plants

    KAUST Repository

    Alshareef, Sahar

    2017-03-27

    Background Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and stresses. Small-molecule inhibitors that perturb splicing provide invaluable tools for use as chemical probes to uncover the molecular underpinnings of splicing regulation and as potential anticancer compounds. Results Here, we show that herboxidiene (GEX1A) inhibits both constitutive and alternative splicing. Moreover, GEX1A activates genome-wide transcriptional patterns involved in abiotic stress responses in plants. GEX1A treatment -activated ABA-inducible promoters, and led to stomatal closure. Interestingly, GEX1A and pladienolide B (PB) elicited similar cellular changes, including alterations in the patterns of transcription and splicing, suggesting that these compounds might target the same spliceosome complex in plant cells. Conclusions Our study establishes GEX1A as a potent splicing inhibitor in plants that can be used to probe the assembly, dynamics, and molecular functions of the spliceosome and to study the interplay between splicing stress and abiotic stresses, as well as having potential biotechnological applications.

  1. Oxidative Stress Responses in the Human Fungal Pathogen, Candida albicans

    Science.gov (United States)

    da Silva Dantas, Alessandra; Day, Alison; Ikeh, Mélanie; Kos, Iaroslava; Achan, Beatrice; Quinn, Janet

    2015-01-01

    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. PMID:25723552

  2. Osmotic stress response in the wine yeast Dekkera bruxellensis.

    Science.gov (United States)

    Galafassi, Silvia; Toscano, Marco; Vigentini, Ileana; Piškur, Jure; Compagno, Concetta

    2013-12-01

    Dekkera bruxellensis is mainly associated with lambic beer fermentation and wine production and may contribute in a positive or negative manner to the flavor development. This yeast is able to produce phenolic compounds, such as 4-ethylguaiacol and 4-ethylphenol which could spoil the wine, depending on their concentration. In this work we have investigated how this yeast responds when exposed to conditions causing osmotic stress, as high sorbitol or salt concentrations. We observed that osmotic stress determined the production and accumulation of intracellular glycerol, and the expression of NADH-dependent glycerol-3-phosphate dehydrogenase (GPD) activity was elevated. The involvement of the HOG MAPK pathway in response to this stress condition was also investigated. We show that in D. bruxellensis Hog1 protein is activated by phosphorylation under hyperosmotic conditions, highlighting the conserved role of HOG MAP kinase signaling pathway in the osmotic stress response. Gene Accession numbers in GenBank: DbHOG1: JX65361, DbSTL1: JX965362. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Hypothalamic and pituitary clusterin modulates neurohormonal responses to stress.

    Science.gov (United States)

    Shin, Mi-Seon; Chang, Hyukki; Namkoong, Churl; Kang, Gil Myoung; Kim, Hyun-Kyong; Gil, So Young; Yu, Ji Hee; Park, Kyeong Han; Kim, Min-Seon

    2013-01-01

    Clusterin is a sulfated glycoprotein abundantly expressed in the pituitary gland and hypothalamus of mammals. However, its physiological role in neuroendocrine function is largely unknown. In the present study, we investigated the effects of intracerebroventricular (ICV) administration of clusterin on plasma pituitary hormone levels in normal rats. Single ICV injection of clusterin provoked neurohormonal changes seen under acute stress condition: increased plasma adrenocorticotropic hormone (ACTH), corticosterone, GH and prolactin levels and decreased LH and FSH levels. Consistently, hypothalamic and pituitary clusterin expression levels were upregulated following a restraint stress, suggesting an involvement of endogenous clusterin in stress-induced neurohormonal changes. In the pituitary intermediate lobe, clusterin was coexpressed with proopiomelanocortin (POMC), a precursor of ACTH. Treatment of clusterin in POMC expressing AtT-20 pituitary cells increased basal and corticotropin-releasing hormone (CRH)-stimulated POMC promoter activities and intracellular cAMP levels. Furthermore, clusterin treatment triggered ACTH secretion from AtT-20 cells in a CRH-dependent manner, indicating that increased clusterin under stressful conditions may augment CRH-stimulated ACTH production and release. In summary, hypothalamic and pituitary clusterin may function as a modulator of neurohormonal responses under stressful conditions. © 2013 S. Karger AG, Basel.

  4. Behaviour and stress responses in horses with gastric ulceration

    DEFF Research Database (Denmark)

    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...... conclude that the prevalence of gastric ulcers was high, and our results suggest different factors affecting ulceration in the glandular versus the nonglandular region of the horse stomach. Obvious external signs (e.g. poor body condition) identifying ulcer horses were absent. Horses with severe glandular...

  5. Compensatory responses induced by oxidative stress in Alzheimer disease

    Directory of Open Access Journals (Sweden)

    PAULA I MOREIRA

    2006-01-01

    Full Text Available Oxidative stress occurs early in the progression of Alzheimer disease, significantly before the development of the pathologic hallmarks, neurofibrillary tangles and senile plaques. In the first stage of development of the disease, amyloid-β deposition and hyperphosphorylated tau function as compensatory responses and downstream adaptations to ensure that neuronal cells do not succumb to oxidative damage. These findings suggest that Alzheimer disease is associated with a novel balance in oxidant homeostasis.

  6. A Unique ISR Program Determines Cellular Responses to Chronic Stress

    Czech Academy of Sciences Publication Activity Database

    Guan, B.J.; van Hoef, V.; Jobava, R.; Elroy-Stein, O.; Valášek, Leoš Shivaya; Cargnello, M.; Gao, X.H.; Krokowski, D.; Merrick, W.C.; Kimball, S.R.; Komar, A.A.; Koromilas, A.E.; Wynshaw-Boris, A.; Topisirovic, I.; Larsson, O.; Hatzoglou, M.

    2017-01-01

    Roč. 68, č. 5 (2017), s. 885-900 ISSN 1097-2765 R&D Projects: GA ČR(CZ) GA17-06238S EU Projects: Wellcome Trust(GB) 090812/B/09/A Institutional support: RVO:61388971 Keywords : UNFOLDED PROTEIN RESPONSE * EUKARYOTIC TRANSLATION INITIATION * ENDOPLASMIC-RETICULUM STRESS Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 14.714, year: 2016

  7. Genome-wide identification and characterization of WRKY transcriptional factor family in apple and analysis of their responses to waterlogging and drought stress.

    Science.gov (United States)

    Meng, Dong; Li, Yuanyuan; Bai, Yang; Li, Mingjun; Cheng, Lailiang

    2016-06-01

    As one of the largest transcriptional factor families in plants, WRKY genes play significant roles in various biotic and abiotic stress responses. Although the WRKY gene family has been characterized in a few plant species, the details remain largely unknown in the apple (Malus domestica Borkh.). In this study, we identified a total of 127 MdWRKYs from the apple genome, which were divided into four subgroups according to the WRKY domains and zinc finger motif. Most of them were mapped onto the apple's 17 chromosomes and were expressed in more than one tissue, including shoot tips, mature leaves, fruit and apple calli. We then contrasted WRKY expression patterns between calli grown in solid medium (control) and liquid medium (representing waterlogging stress) and found that 34 WRKY genes were differentially expressed between the two growing conditions. Finally, we determined the expression patterns of 10 selected WRKY genes in an apple rootstock, G41, in response to waterlogging and drought stress, which identified candidate genes involved in responses to water stress for functional analysis. Our data provide interesting candidate MdWRKYs for future functional analysis and demonstrate that apple callus is a useful system for characterizing gene expression and function in apple. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Epidermal stem cells response to radiative genotoxic stress

    International Nuclear Information System (INIS)

    Marie, Melanie

    2013-01-01

    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

  9. Leptin regulates dopamine responses to sustained stress in humans.

    Science.gov (United States)

    Burghardt, Paul R; Love, Tiffany M; Stohler, Christian S; Hodgkinson, Colin; Shen, Pei-Hong; Enoch, Mary-Anne; Goldman, David; Zubieta, Jon-Kar

    2012-10-31

    Neural systems that identify and respond to salient stimuli are critical for survival in a complex and changing environment. In addition, interindividual differences, including genetic variation and hormonal and metabolic status likely influence the behavioral strategies and neuronal responses to environmental challenges. Here, we examined the relationship between leptin allelic variation and plasma leptin levels with DAD2/3R availability in vivo as measured with [(11)C]raclopride PET at baseline and during a standardized pain stress challenge. Allelic variation in the leptin gene was associated with varying levels of dopamine release in response to the pain stressor, but not with baseline D2/3 receptor availability. Circulating leptin was also positively associated with stress-induced dopamine release. These results show that leptin serves as a regulator of neuronal function in humans and provides an etiological mechanism for differences in dopamine neurotransmission in response to salient stimuli as related to metabolic function. The capacity for leptin to influence stress-induced dopaminergic function is of importance for pathological states where dopamine is thought to play an integral role, such as mood, substance-use disorders, eating disorders, and obesity.

  10. Stress Transmission in Granular Packings: Localization and Cooperative Response

    Science.gov (United States)

    Ramola, Kabir

    We develop a framework for stress transmission in two dimensional granular media that respects vector force balance at the microscopic level. For a packing of grains interacting via pairwise contact forces, we introduce local gauge degrees of freedom that determine the response of the system to external perturbations. This allows us to construct unique force-balanced solutions that determine the change in contact forces as a response to external stress. By mapping this response to diffusion in the underlying contact network, we show that this naturally leads to spatial localization of forces. We present numerical evidence for stress localization using exact diagonalization studies of network Laplacians associated with soft disk packings. We use this formalism to characterize the deviation from elastic behaviour as the amount of disorder in the underlying network is varied. We discuss generalizations to systems with large friction between grains and other networks that display topological disorder. This work has been supported by NSF-DMR 1409093 and the W. M. Keck Foundation.

  11. Sex and stress: Men and women show different cortisol responses to psychological stress induced by the Trier social stress test and the Iowa singing social stress test.

    Science.gov (United States)

    Reschke-Hernández, Alaine E; Okerstrom, Katrina L; Bowles Edwards, Angela; Tranel, Daniel

    2017-01-02

    Acute psychological stress affects each of us in our daily lives and is increasingly a topic of discussion for its role in mental illness, aging, cognition, and overall health. A better understanding of how such stress affects the body and mind could contribute to the development of more effective clinical interventions and prevention practices. Over the past 3 decades, the Trier Social Stress Test (TSST) has been widely used to induce acute stress in a laboratory setting based on the principles of social evaluative threat, namely, a judged speech-making task. A comparable alternative task may expand options for examining acute stress in a controlled laboratory setting. This study uses a within-subjects design to examine healthy adult participants' (n = 20 men, n = 20 women) subjective stress and salivary cortisol responses to the standard TSST (involving public speaking and math) and the newly created Iowa Singing Social Stress Test (I-SSST). The I-SSST is similar to the TSST but with a new twist: public singing. Results indicated that men and women reported similarly high levels of subjective stress in response to both tasks. However, men and women demonstrated different cortisol responses; men showed a robust response to both tasks, and women displayed a lesser response. These findings are in line with previous literature and further underscore the importance of examining possible sex differences throughout various phases of research, including design, analysis, and interpretation of results. Furthermore, this nascent examination of the I-SSST suggests a possible alternative for inducing stress in the laboratory. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Cortisol responses to naturalistic and laboratory stress in student teachers: comparison with a non-stress control day.

    Science.gov (United States)

    Wolfram, Maren; Bellingrath, Silja; Feuerhahn, Nicolas; Kudielka, Brigitte M

    2013-04-01

    Ambulatory assessments of hypothalamus-pituitary-adrenal axis responses to acute natural stressors yield evidence on stress regulation with high ecological validity. Sampling of salivary cortisol is a standard technique in this field. In 21 healthy student teachers, we assessed cortisol responses to a demonstration lesson. On a control day, sampling was repeated at analogous times. Additionally, the cortisol awakening response (CAR) was assessed on both days. Participants were also exposed to a laboratory stressor, the Trier Social Stress Test, and rated their individual levels of chronic work stress. In pre-to-post-stress assessment, cortisol levels declined after the lesson. However, post-stress cortisol levels were significantly higher compared with those on the control day. Also, the Trier Social Stress Test yielded higher cortisol responses when using the control day as reference baseline. Associations between the CAR and chronic stress measures were observed solely on the control day. There were no significant associations between cortisol responses to the natural and laboratory stressors. Our results indicate that a control day might be an important complement in laboratory but especially in ambulatory stress research. Furthermore, associations between chronic stress measures and the CAR might be obscured by acute stress exposure. Finally, responses to the laboratory stressor do not seem to mirror natural stress responses. Copyright © 2012 John Wiley & Sons, Ltd.

  13. Lifelong Aerobic Exercise Reduces the Stress Response in Rats.

    Science.gov (United States)

    Pietrelli, A; Di Nardo, M; Masucci, A; Brusco, A; Basso, N; Matkovic, L

    2018-04-15

    The aim of this study was to analyze the effects of lifelong aerobic exercise (AE) on the adaptive response of the stress system in rats. It is well known that hypothalamic-pituitary-adrenal axis (HPA) activity differs when triggered by voluntary or forced exercise models. Male Wistar rats belonging to exercise (E) or control (C) groups were subjected to chronic AE, and two cutoff points were established at 8 (middle age) and 18 months (old age). Behavioral, biochemical and histopathological studies were performed on the main components/targets of the stress system. AE increased adrenal sensitivity (AS), brain corticosterone (CORT) and corticotropin-releasing factor (CRF), but had no effect on the thymus, adrenal glands (AGs) weight or plasma CORT. In addition, AE exerted no effect on the sympathetic tone, but significantly reduced anxiety-related behavior and emotionality. Aging decreased AS and deregulated neuroendocrine feedback, leading to an anxiogenic state which was mitigated by AE. Histopathological and morphometric analysis of AGs showed no alterations in middle-aged rats but adrenal vacuolization in approximately 20% old rats. In conclusion, lifelong AE did not produce adverse effects related to a chronic stress state. On the contrary, while AE upregulated some components of the HPA axis, it generated an adaptive response to cumulative changes, possibly through different compensatory and/or super compensatory mechanisms, modulated by age. The long-term practice of AE had a strong positive impact on stress resilience so that it could be recommended as a complementary therapy in stress and depression disease. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Dose response relationship in anti-stress gene regulatory networks.

    Science.gov (United States)

    Zhang, Qiang; Andersen, Melvin E

    2007-03-02

    To maintain a stable intracellular environment, cells utilize complex and specialized defense systems against a variety of external perturbations, such as electrophilic stress, heat shock, and hypoxia, etc. Irrespective of the type of stress, many adaptive mechanisms contributing to cellular homeostasis appear to operate through gene regulatory networks that are organized into negative feedback loops. In general, the degree of deviation of the controlled variables, such as electrophiles, misfolded proteins, and O2, is first detected by specialized sensor molecules, then the signal is transduced to specific transcription factors. Transcription factors can regulate the expression of a suite of anti-stress genes, many of which encode enzymes functioning to counteract the perturbed variables. The objective of this study was to explore, using control theory and computational approaches, the theoretical basis that underlies the steady-state dose response relationship between cellular stressors and intracellular biochemical species (controlled variables, transcription factors, and gene products) in these gene regulatory networks. Our work indicated that the shape of dose response curves (linear, superlinear, or sublinear) depends on changes in the specific values of local response coefficients (gains) distributed in the feedback loop. Multimerization of anti-stress enzymes and transcription factors into homodimers, homotrimers, or even higher-order multimers, play a significant role in maintaining robust homeostasis. Moreover, our simulation noted that dose response curves for the controlled variables can transition sequentially through four distinct phases as stressor level increases: initial superlinear with lesser control, superlinear more highly controlled, linear uncontrolled, and sublinear catastrophic. Each phase relies on specific gain-changing events that come into play as stressor level increases. The low-dose region is intrinsically nonlinear, and depending on

  15. Dose response relationship in anti-stress gene regulatory networks.

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2007-03-01

    Full Text Available To maintain a stable intracellular environment, cells utilize complex and specialized defense systems against a variety of external perturbations, such as electrophilic stress, heat shock, and hypoxia, etc. Irrespective of the type of stress, many adaptive mechanisms contributing to cellular homeostasis appear to operate through gene regulatory networks that are organized into negative feedback loops. In general, the degree of deviation of the controlled variables, such as electrophiles, misfolded proteins, and O2, is first detected by specialized sensor molecules, then the signal is transduced to specific transcription factors. Transcription factors can regulate the expression of a suite of anti-stress genes, many of which encode enzymes functioning to counteract the perturbed variables. The objective of this study was to explore, using control theory and computational approaches, the theoretical basis that underlies the steady-state dose response relationship between cellular stressors and intracellular biochemical species (controlled variables, transcription factors, and gene products in these gene regulatory networks. Our work indicated that the shape of dose response curves (linear, superlinear, or sublinear depends on changes in the specific values of local response coefficients (gains distributed in the feedback loop. Multimerization of anti-stress enzymes and transcription factors into homodimers, homotrimers, or even higher-order multimers, play a significant role in maintaining robust homeostasis. Moreover, our simulation noted that dose response curves for the controlled variables can transition sequentially through four distinct phases as stressor level increases: initial superlinear with lesser control, superlinear more highly controlled, linear uncontrolled, and sublinear catastrophic. Each phase relies on specific gain-changing events that come into play as stressor level increases. The low-dose region is intrinsically nonlinear

  16. Responses to reductive stress in the cardiovascular system.

    Science.gov (United States)

    Handy, Diane E; Loscalzo, Joseph

    2017-08-01

    There is a growing appreciation that reductive stress represents a disturbance in the redox state that is harmful to biological systems. On a cellular level, the presence of increased reducing equivalents and the lack of beneficial fluxes of reactive oxygen species can prevent growth factor-mediated signaling, promote mitochondrial dysfunction, increase apoptosis, and decrease cell survival. In this review, we highlight the importance of redox balance in maintaining cardiovascular homeostasis and consider the tenuous balance between oxidative and reductive stress. We explain the role of reductive stress in models of protein aggregation-induced cardiomyopathies, such as those caused by mutations in αB-crystallin. In addition, we discuss the role of NADPH oxidases in models of heart failure and ischemia-reperfusion to illustrate how oxidants may mediate the adaptive responses to injury. NADPH oxidase 4, a hydrogen peroxide generator, also has a major role in promoting vascular homeostasis through its regulation of vascular tone, angiogenic responses, and effects on atherogenesis. In contrast, the lack of antioxidant enzymes that reduce hydrogen peroxide, such as glutathione peroxidase 1, promotes vascular remodeling and is deleterious to endothelial function. Thus, we consider the role of oxidants as necessary signals to promote adaptive responses, such as the activation of Nrf2 and eNOS, and the stabilization of Hif1. In addition, we discuss the adaptive metabolic reprogramming in hypoxia that lead to a reductive state, and the subsequent cellular redistribution of reducing equivalents from NADH to other metabolites. Finally, we discuss the paradoxical ability of excess reducing equivalents to stimulate oxidative stress and promote injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Variety of immune responses to chronic stress in rats male

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    Іlona S Polovynko

    2016-12-01

    Full Text Available Background. Previously we have been carry out integrated quantitative estimation of neuroendocrine and immune responses to chronic restraint stress in male rats. Revealed that the value of canonical discriminant roots rats subjected to chronic stress different not only on the values of intact animals (by definition, but also among themselves. So we set a goal retrospectively divided stressed rats into three homogeneous groups. Material and methods. The experiment is at 50 white male rats. Of these 10 animals not subjected to any influences and 40 within 7 days subjected to moderate stress by daily 30-minute immobilization. The day after the completion of stressing in portion of the blood immunological parameters were determined by tests I and II levels of WHO. The spleen and thymus did smears for counting spleno- and thymocytograms. Results. The method of cluster analysis (k-means clustering formed three groups-clusters. For further analysis selected 18 parameters that members of each cluster differing minimum and maximum are different from members of other clusters (η2=0,73÷0,15; F=49,0÷3,26; p=10-6÷0,05. We stated that in 16 rats from cluster III the deviation 16 parameters in either side of the average norm almost identical and are in an acceptable range of ±0,5σ. Thus, the immune status of 40% of the rats subjected to moderate chronic stress was resistant to its factors. For the immune status of the 15 (37,5% rats cluster II typical moderate inhibition microphage, killer and T-cellular links in combination with a strong activation macrophage link. Poststressory changes in immunity in 9 rats (22,5% from cluster I differ from those in cluster II both qualitatively and quantitatively. In particular, the rats in this cluster were found no deviations from the norm or reaction blast transformation T-cells nor NK-lymphocytes levels. However, other parameters of T-link and microhage link suppressed more and settings macrophage link appeared

  18. Jasmonates: biosynthesis, perception, signal transduction and action in plant stress response, growth and development. An update to the 2007 review in Annals of Botany.

    Science.gov (United States)

    Wasternack, C; Hause, B

    2013-06-01

    Jasmonates are important regulators in plant responses to biotic and abiotic stresses as well as in development. Synthesized from lipid-constituents, the initially formed jasmonic acid is converted to different metabolites including the conjugate with isoleucine. Important new components of jasmonate signalling including its receptor were identified, providing deeper insight into the role of jasmonate signalling pathways in stress responses and development. The present review is an update of the review on jasmonates published in this journal in 2007. New data of the last five years are described with emphasis on metabolites of jasmonates, on jasmonate perception and signalling, on cross-talk to other plant hormones and on jasmonate signalling in response to herbivores and pathogens, in symbiotic interactions, in flower development, in root growth and in light perception. The last few years have seen breakthroughs in the identification of JASMONATE ZIM DOMAIN (JAZ) proteins and their interactors such as transcription factors and co-repressors, and the crystallization of the jasmonate receptor as well as of the enzyme conjugating jasmonate to amino acids. Now, the complex nature of networks of jasmonate signalling in stress responses and development including hormone cross-talk can be addressed.

  19. Transcriptome response mediated by cold stress in Lotus japonicus

    Directory of Open Access Journals (Sweden)

    Pablo Ignacio Calzadilla

    2016-03-01

    Full Text Available Members of the Lotus genus are important as agricultural forage sources under marginal environmental conditions given their high nutritional value and tolerance of various abiotic stresses. However, their dry matter production is drastically reduced in cooler seasons, while their response to such conditions is not well studied. This paper analyzes cold acclimation of the genus by studying Lotus japonicus over a stress period of 24 h. High-throughput RNA sequencing was used to identify and classify 1077 differentially expressed genes, of which 713 were up-regulated and 364 were down-regulated. Up-regulated genes were principally related to lipid, cell wall, phenylpropanoid, sugar, and proline regulation, while down-regulated genes affected the photosynthetic process and chloroplast development. Together, a total of 41 cold-inducible transcription factors were identified, including members of the AP2/ERF, NAC, MYB, and WRKY families; two of them were described as putative novel transcription factors. Finally, DREB1/CBFs were described with respect to their cold stress expression profiles. This is the first transcriptome profiling of the model legume L. japonicus under cold stress. Data obtained may be useful in identifying candidate genes for breeding modified species of forage legumes that more readily acclimate to low temperatures

  20. Plant responses to environmental stresses-from gene to biotechnology.

    Science.gov (United States)

    Ahanger, Mohammad Abass; Akram, Nudrat Aisha; Ashraf, Muhammad; Alyemeni, Mohammed Nasser; Wijaya, Leonard; Ahmad, Parvaiz

    2017-07-01

    Increasing global population, urbanization and industrialization are increasing the rate of conversion of arable land into wasteland. Supplying food to an ever-increasing population is one of the biggest challenges that agriculturalists and plant scientists are currently confronting. Environmental stresses make this situation even graver. Despite the induction of several tolerance mechanisms, sensitive plants often fail to survive under environmental extremes. New technological approaches are imperative. Conventional breeding methods have a limited potential to improve plant genomes against environmental stress. Recently, genetic engineering has contributed enormously to the development of genetically modified varieties of different crops such as cotton, maize, rice, canola and soybean. The identification of stress-responsive genes and their subsequent introgression or overexpression within sensitive crop species are now being widely carried out by plant scientists. Engineering of important tolerance pathways, like antioxidant enzymes, osmolyte accumulation, membrane-localized transporters for efficient compartmentation of deleterious ions and accumulation of essential elements and resistance against pests or pathogens is also an area that has been intensively researched. In this review, the role of biotechnology and its successes, prospects and challenges in developing stress-tolerant crop cultivars are discussed.

  1. Endoplasmic Reticulum Stress, Unfolded Protein Response, and Cancer Cell Fate

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    Marco Corazzari

    2017-04-01

    Full Text Available Perturbation of endoplasmic reticulum (ER homeostasis results in a stress condition termed “ER stress” determining the activation of a finely regulated program defined as unfolded protein response (UPR and whose primary aim is to restore this organelle’s physiological activity. Several physiological and pathological stimuli deregulate normal ER activity causing UPR activation, such as hypoxia, glucose shortage, genome instability, and cytotoxic compounds administration. Some of these stimuli are frequently observed during uncontrolled proliferation of transformed cells, resulting in tumor core formation and stage progression. Therefore, it is not surprising that ER stress is usually induced during solid tumor development and stage progression, becoming an hallmark of such malignancies. Several UPR components are in fact deregulated in different tumor types, and accumulating data indicate their active involvement in tumor development/progression. However, although the UPR program is primarily a pro-survival process, sustained and/or prolonged stress may result in cell death induction. Therefore, understanding the mechanism(s regulating the cell survival/death decision under ER stress condition may be crucial in order to specifically target tumor cells and possibly circumvent or overcome tumor resistance to therapies. In this review, we discuss the role played by the UPR program in tumor initiation, progression and resistance to therapy, highlighting the recent advances that have improved our understanding of the molecular mechanisms that regulate the survival/death switch.

  2. Reconstructing a Network of Stress-Response Regulators via Dynamic System Modeling of Gene Regulation

    Directory of Open Access Journals (Sweden)

    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.

  3. Pairing of heterochromatin in response to cellular stress

    International Nuclear Information System (INIS)

    Abdel-Halim, H.I.; Mullenders, L.H.F.; Boei, J.J.W.A.

    2006-01-01

    We previously reported that exposure of human cells to DNA-damaging agents (X-rays and mitomycin C (MMC)) induces pairing of the homologous paracentromeric heterochromatin of chromosome 9 (9q12-13). Here, we show that UV irradiation and also heat shock treatment of human cells lead to similar effects. Since the various agents induce very different types and frequencies of damage to cellular constituents, the data suggest a general stress response as the underlying mechanism. Moreover, local UV irradiation experiments revealed that pairing of heterochromatin is an event that can be triggered without induction of DNA damage in the heterochromatic sequences. The repair deficient xeroderma pigmentosum cells (group F) previously shown to fail pairing after MMC displayed elevated pairing after heat shock treatment but not after UV exposure. Taken together, the present results indicate that pairing of heterochromatin following exposure to DNA-damaging agents is initiated by a general stress response and that the sensing of stress or the maintenance of the paired status of the heterochromatin might be dependent on DNA repair

  4. Mcm2 phosphorylation and the response to replicative stress

    Directory of Open Access Journals (Sweden)

    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

  5. Does spending time outdoors reduce stress? A review of real-time stress response to outdoor environments

    Science.gov (United States)

    Michelle C. Kondo; Sara F. Jacoby; Eugenia C. South

    2018-01-01

    Everyday environmental conditions impact human health. One mechanism underlying this relationship is the experience of stress. Through systematic review of published literature, we explore how stress has been measured in real-time non-laboratory studies of stress responses to deliberate exposure to outdoor environments. The types of exposures evaluated in this review...

  6. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands

    NARCIS (Netherlands)

    Harmsen, R; Helms-Lorenz, M.; Maulana, R; van Veen, K; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the

  7. Adrenal cortical response to stress at Three Mile Island.

    Science.gov (United States)

    Schaeffer, M A; Baum, A

    1984-01-01

    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.

  8. Microtubules self-repair in response to mechanical stress

    Science.gov (United States)

    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.

  9. Adrenal cortical response to stress at Three Mile Island

    International Nuclear Information System (INIS)

    Schaeffer, M.A.; Baum, A.

    1984-01-01

    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

  10. Genomic counter-stress changes induced by the relaxation response.

    Directory of Open Access Journals (Sweden)

    Jeffery A Dusek

    2008-07-01

    Full Text Available 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.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.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 investigations into applying transcriptional profiling for accurately measuring

  11. The significance of translation regulation in the stress response

    Science.gov (United States)

    2013-01-01

    Background The stress response in bacteria involves the multistage control of gene expression but is not entirely understood. To identify the translational response of bacteria in stress conditions and assess its contribution to the regulation of gene expression, the translational states of all mRNAs were compared under optimal growth condition and during nutrient (isoleucine) starvation. Results A genome-scale study of the translational response to nutritional limitation was performed in the model bacterium Lactococcus lactis. Two measures were used to assess the translational status of each individual mRNA: the fraction engaged in translation (ribosome occupancy) and ribosome density (number of ribosomes per 100 nucleotides). Under isoleucine starvation, half of the mRNAs considered were translationally down-regulated mainly due to decreased ribosome density. This pattern concerned genes involved in growth-related functions such as translation, transcription, and the metabolism of fatty acids, phospholipids and bases, contributing to the slowdown of growth. Only 4% of the mRNAs were translationally up-regulated, mostly related to prophagic expression in response to stress. The remaining genes exhibited antagonistic regulations of the two markers of translation. Ribosome occupancy increased significantly for all the genes involved in the biosynthesis of isoleucine, although their ribosome density had decreased. The results revealed complex translational regulation of this pathway, essential to cope with isoleucine starvation. To elucidate the regulation of global gene expression more generally, translational regulation was compared to transcriptional regulation under isoleucine starvation and to other post-transcriptional regulations related to mRNA degradation and mRNA dilution by growth. Translational regulation appeared to accentuate the effects of transcriptional changes for down-regulated growth-related functions under isoleucine starvation although m

  12. Mitochondria, Energetics, Epigenetics, and Cellular Responses to Stress

    Science.gov (United States)

    McAllister, Kimberly; Worth, Leroy; Haugen, Astrid C.; Meyer, Joel N.; Domann, Frederick E.; Van Houten, Bennett; Mostoslavsky, Raul; Bultman, Scott J.; Baccarelli, Andrea A.; Begley, Thomas J.; Sobol, Robert W.; Hirschey, Matthew D.; Ideker, Trey; Santos, Janine H.; Copeland, William C.; Tice, Raymond R.; Balshaw, David M.; Tyson, Frederick L.

    2014-01-01

    Background: Cells respond to environmental stressors through several key pathways, including response to reactive oxygen species (ROS), nutrient and ATP sensing, DNA damage response (DDR), and epigenetic alterations. Mitochondria play a central role in these pathways not only through energetics and ATP production but also through metabolites generated in the tricarboxylic acid cycle, as well as mitochondria–nuclear signaling related to mitochondria morphology, biogenesis, fission/fusion, mitophagy, apoptosis, and epigenetic regulation. Objectives: We investigated the concept of bidirectional interactions between mitochondria and cellular pathways in response to environmental stress with a focus on epigenetic regulation, and we examined DNA repair and DDR pathways as examples of biological processes that respond to exogenous insults through changes in homeostasis and altered mitochondrial function. Methods: The National Institute of Environmental Health Sciences sponsored the Workshop on Mitochondria, Energetics, Epigenetics, Environment, and DNA Damage Response on 25–26 March 2013. Here, we summarize key points and ideas emerging from this meeting. Discussion: A more comprehensive understanding of signaling mechanisms (cross-talk) between the mitochondria and nucleus is central to elucidating the integration of mitochondrial functions with other cellular response pathways in modulating the effects of environmental agents. Recent studies have highlighted the importance of mitochondrial functions in epigenetic regulation and DDR with environmental stress. Development and application of novel technologies, enhanced experimental models, and a systems-type research approach will help to discern how environmentally induced mitochondrial dysfunction affects key mechanistic pathways. Conclusions: Understanding mitochondria–cell signaling will provide insight into individual responses to environmental hazards, improving prediction of hazard and susceptibility to

  13. Exercise-induced stress responses of amenorrheic and eumenorrheic runners.

    Science.gov (United States)

    Loucks, A B; Horvath, S M

    1984-12-01

    The role of stress in exercise-associated amenorrhea was investigated. Sex hormones [FSH, LH, androstenedione (A), testosterone, estrone, and 17 beta-estradiol (E2)], stress hormones [dehydroepiandrosterone, cortisol (F), PRL, norepinephrine, and epinephrine] and psychological status (Profile of Mood States and State-Trait Anxiety Inventory) were measured at rest and in response to a 40-min 80% of maximal aerobic power (VO2max) run in highly trained eumenorrheic (n = 8) and amenorrheic (n = 7) women runners matched for fatness [eumenorrheic, 16.5 +/- 2.3% (+/- SD); amenorrheic, 14.9 +/- 4.8] and maximal aerobic power (eumenorrheic, 58.9 +/- 5.7 ml/kg X min; amenorrheic, 59.8 +/- 4.6). Eumenorrheic runners were tested between days 3 and 8 of the follicular phase. At rest, decreased plasma FSH, LH, and E2 concentrations were found in amenorrheic women [eumenorrheic FSH, 10.5 +/- 4.1 mIU/ml; amenorrheic FSH, 4.9 +/- 1.6 (P less than 0.01); eumenorrheic LH, 14.1 +/- 6.1 mIU/ml; amenorrheic LH, 5.1 +/- 1.7 (P less than 0.01); eumenorrheic E2, 20 +/- 9 pg/ml; amenorrheic E2, 7 +/- 6 (P less than 0.05)]. Other sex and stress hormones and psychological measurements were similar in the two groups and were within the normal range. Ventilatory, cardiovascular, thermoregulatory, and psychological responses to the submaximal run were identical. Among eumenorrheic women, all stress hormones and A increased after exercise, but PRL, F, and A were unchanged among amenorrheic women. Estrone, E2, and testosterone did not change in either group. These observations are inconsistent with a general stress hypothesis of exercise-associated amenorrhea as well as with more specific hyperprolactinemic and hyperandrogenic hypotheses. In amenorrheic women, failure of PRL to increase in response to exercise may be due to their lack of E2, while failure of F and A to increase may indicate reduced adrenal 3 beta-hydroxysteroid dehydrogenase/isomerase activity.

  14. Neonatal stress tempers vulnerability of acute stress response in adult socially isolated rats

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    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

  15. Oxidative and nitrosative stress in trichloroethene-mediated autoimmune response

    International Nuclear Information System (INIS)

    Wang Gangduo; Cai Ping; Ansari, G.A.S.; Khan, M. Firoze

    2007-01-01

    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

  16. Evaluation of nutritional substrate and physical stress (gamma ...

    African Journals Online (AJOL)

    The β-glucans productivity of the mushroom depends upon the growing conditions, nutritional substrates, biotic and abiotic stress factors that result in an enzymes over-expression. The study shows the potential response of glucan production by fungi grown on newly designed animal plant crude (hydrolyzate) extract broth ...

  17. 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

    Directory of Open Access Journals (Sweden)

    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

  18. Exploring the Response of Plants Grown under Uranium Stress

    Energy Technology Data Exchange (ETDEWEB)

    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

  19. Redox systems are a potential link between drought stress susceptibility and the exacerbation of aflatoxin contamination in crops

    Science.gov (United States)

    Drought stress aggravates Aspergillus flavus infection and aflatoxin contamination in oilseed crops such as peanut and maize. Reactive oxygen species (ROS) are produced in plants in response to abiotic and biotic stresses as a means of defense. In the host plant-A. flavus interaction under drought c...

  20. Genome-Wide Characterization of Heat-Shock Protein 70s from Chenopodium quinoa and Expression Analyses of Cqhsp70s in Response to Drought Stress.

    Science.gov (United States)

    Liu, Jianxia; Wang, Runmei; Liu, Wenying; Zhang, Hongli; Guo, Yaodong; Wen, Riyu

    2018-01-23

    Heat-shock proteins (HSPs) are ubiquitous proteins with important roles in response to biotic and abiotic stress. The 70-kDa heat-shock genes ( Hsp70s ) encode a group of conserved chaperone proteins that play central roles in cellular networks of molecular chaperones and folding catalysts across all the studied organisms including bacteria, plants and animals. Several Hsp70s involved in drought tolerance have been well characterized in various plants, whereas no research on Chenopodium quinoa HSPs has been completed. Here, we analyzed the genome of C. quinoa and identified sixteen Hsp70 members in quinoa genome. Phylogenetic analysis revealed the independent origination of those Hsp70 members, with eight paralogous pairs comprising the Hsp70 family in quinoa. While the gene structure and motif analysis showed high conservation of those paralogous pairs, the synteny analysis of those paralogous pairs provided evidence for expansion coming from the polyploidy event. With several subcellular localization signals detected in CqHSP70 protein paralogous pairs, some of the paralogous proteins lost the localization information, indicating the diversity of both subcellular localizations and potential functionalities of those HSP70s. Further gene expression analyses revealed by quantitative polymerase chain reaction (qPCR) analysis illustrated the significant variations of Cqhsp70s in response to drought stress. In conclusion, the sixteen Cqhsp70 s undergo lineage-specific expansions and might play important and varied roles in response to drought stress.

  1. Coevolutionary aesthetics in human and biotic artworlds.

    Science.gov (United States)

    Prum, Richard O

    2013-01-01

    This work proposes a coevolutionary theory of aesthetics that encompasses both biotic and human arts. Anthropocentric perspectives in aesthetics prevent the recognition of the ontological complexity of the aesthetics of nature, and the aesthetic agency of many non-human organisms. The process of evaluative coevolution is shared by all biotic advertisements. I propose that art consists of a form of communication that coevolves with its own evaluation. Art and art history are population phenomena. I expand Arthur Danto's Artworld concept to any aesthetic population of producers and evaluators. Current concepts of art cannot exclusively circumscribe the human arts from many forms of non-human biotic art. Without assuming an arbitrarily anthropocentric perspective, any concept of art will need to engage with biodiversity, and either recognize many instances of biotic advertisements as art, or exclude some instances of human art. Coevolutionary aesthetic theory provides a heuristic account of aesthetic change in both human and biotic artworlds, including the coevolutionary origin of aesthetic properties and aesthetic value within artworlds. Restructuring aesthetics, art criticism, and art history without human beings at the organizing centers of these disciplines stimulate new progress in our understanding of art, and the unique human contributions to aesthetics and aesthetic diversity.

  2. Response of tropical trees to sulphur dioxide stress and recovery

    Energy Technology Data Exchange (ETDEWEB)

    Vartshney, C.K.; Mitra, I. [Jawaharlal Nehru University, New Delhi (India). School of Environmental Sciences

    1995-12-31

    Ethylene emission, ascorbic acid content, peroxidase and superoxide dismutase activity were measured in four tropical tree species. Six month old saplings of Morus alba Linn., Azadirachta indica A.Juss., Melia-azadirach Linn. and Syzgium jambolina Lamk, were exposed to 0.5 ppm SO{sub 2} for four hours for six consecutive days. Recovery from SO{sub 2} stress was followed for twelve days after termination of the fumigation. SO{sub 2} induced foliar ethylene emission increased during fumigation but declined following termination of fumigation. SO{sub 2} fumigation enhanced the activities of superoxide dismutase and peroxidase in all four species. Their activities, however, declined on withdrawal of SO{sub 2} stress. Ascorbic acid content decreased due to SO{sub 2} stress but exhibited recovery on termination of fumigation. The response of the four plant species was widely different both during the fumigation period and during post-fumigation recovery regime. 26 refs., 3 figs., 2 tabs.

  3. Quorum sensing regulates the osmotic stress response in Vibrio harveyi.

    Science.gov (United States)

    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. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  4. Molecular and physiological responses of trees to waterlogging stress.

    Science.gov (United States)

    Kreuzwieser, Jürgen; Rennenberg, Heinz

    2014-10-01

    One major effect of global climate change will be altered precipitation patterns in many regions of the world. This will cause a higher probability of long-term waterlogging in winter/spring and flash floods in summer because of extreme rainfall events. Particularly, trees not adapted at their natural site to such waterlogging stress can be impaired. Despite the enormous economic, ecological and social importance of forest ecosystems, the effect of waterlogging on trees is far less understood than the effect on many crops or the model plant Arabidopsis. There is only a handful of studies available investigating the transcriptome and metabolome of waterlogged trees. Main physiological responses of trees to waterlogging include the stimulation of fermentative pathways and an accelerated glycolytic flux. Many energy-consuming, anabolic processes are slowed down to overcome the energy crisis mediated by waterlogging. A crucial feature of waterlogging tolerance is the steady supply of glycolysis with carbohydrates, particularly in the roots; stress-sensitive trees fail to maintain sufficient carbohydrate availability resulting in the dieback of the stressed tissues. The present review summarizes physiological and molecular features of waterlogging tolerance of trees; the focus is on carbon metabolism in both, leaves and roots of trees. © 2014 John Wiley & Sons Ltd.

  5. Stress-strain response of plastic waste mixed soil.

    Science.gov (United States)

    Babu, G L Sivakumar; Chouksey, Sandeep Kumar

    2011-03-01

    Recycling plastic waste from water bottles has become one of the major challenges worldwide. The present study provides an approach for the use plastic waste as reinforcement material in soil. The experimental results in the form of stress-strain-pore water pressure response are presented. Based on experimental test results, it is observed that the strength of soil is improved and compressibility reduced significantly with addition of a small percentage of plastic waste to the soil. The use of the improvement in strength and compressibility response due to inclusion of plastic waste can be advantageously used in bearing capacity improvement and settlement reduction in the design of shallow foundations. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Stress, and pathogen response gene expression in modeled microgravity

    Science.gov (United States)

    Sundaresan, Alamelu; Pellis, Neal R.

    2006-01-01

    Purpose: Immune suppression in microgravity has been well documented. With the advent of human exploration and long-term space travel, the immune system of the astronaut must be optimally maintained. It is important to investigate the expression patterns of cytokine genes, because they are directly related to immune response. Heat shock proteins (HSPs), also called stress proteins, are a group of proteins that are present in the cells of every life form. These proteins are induced when a cell responds to stressors such as heat, cold and oxygen deprivation. Microgravity is another stressor that may regulate HSPs. Heat shock proteins trigger immune response through activities that occur both inside the cell (intracellular) and outside the cell (extracellular). Knowledge about these two gene groups could lead to establishment of a blueprint of the immune response and adaptation-related genes in the microgravity environment. Methods: Human peripheral blood cells were cultured in 1g (T flask) and modeled microgravity (MMG, rotating-wall vessel) for 24 and 72 hours. Cell samples were collected and subjected to gene array analysis using the Affymetrix HG_U95 array. Data was collected and subjected to a two-way analysis of variance. The genes related to immune and stress responses were analyzed. Results and Conclusions: HSP70 was up-regulated by more than two fold in microgravity culture, while HSP90 was significantly down-regulated. HSP70 is not typically expressed in all kinds of cells, but it is expressed at high levels in stress conditions. HSP70 participates in translation, protein translocation, proteolysis and protein folding, suppressing aggregation and reactivating denatured proteins. Increased serum HSP70 levels correlate with a better outcome for heat-stroke or severe trauma patients. At the same time, elevated serum levels of HSP70 have been detected in patients with peripheral or renal vascular disease. HSP90 has been identified in the cytosol, nucleus and

  7. Biotic turnover rates during the Pleistocene-Holocene transition

    Science.gov (United States)

    Stivrins, Normunds; Soininen, Janne; Amon, Leeli; Fontana, Sonia L.; Gryguc, Gražyna; Heikkilä, Maija; Heiri, Oliver; Kisielienė, Dalia; Reitalu, Triin; Stančikaitė, Miglė; Veski, Siim; Seppä, Heikki

    2016-11-01

    The Northern Hemisphere is currently warming at the rate which is unprecedented during the Holocene. Quantitative palaeoclimatic records show that the most recent time in the geological history with comparable warming rates was during the Pleistocene-Holocene transition (PHT) about 14,000 to 11,000 years ago. To better understand the biotic response to rapid temperature change, we explore the community turnover rates during the PHT by focusing on the Baltic region in the southeastern sector of the Scandinavian Ice Sheet, where an exceptionally dense network on microfossil and macrofossil data that reflect the biotic community history are available. We further use a composite chironomid-based summer temperature reconstruction compiled specifically for our study region to calculate the rate of temperature change during the PHT. The fastest biotic turnover in the terrestrial and aquatic communities occurred during the Younger Dryas-Holocene shift at 11,700 years ago. This general shift in species composition was accompanied by regional extinctions, including disappearance of mammoth (Mammuthus primigenius) and reindeer (Rangifer tarandus) and many arctic-alpine plant taxa, such as Dryas octopetala, Salix polaris and Saxifraga aizoides, from the region. This rapid biotic turnover rate occurred when the rate of warming was 0.17 °C/decade, thus slightly lower than the current Northern Hemisphere warming of 0.2 °C/decade. We therefore conclude that the Younger Dryas-Holocene shift with its rapid turnover rates and associated regional extinctions represents an important palaeoanalogue to the current high latitude warming and gives insights about the probable future turnover rates and patterns of the terrestrial and aquatic ecosystem change.

  8. Transcriptomic Response of Chinese Yew (Taxus chinensis to Cold Stress

    Directory of Open Access Journals (Sweden)

    Xianghua Yu

    2017-04-01

    Full Text Available Taxus chinensis is a rare and endangered shrub, highly sensitive to temperature changes and widely known for its potential in cancer treatment. How gene expression of T. chinensis responds to low temperature is still unknown. To investigate cold response of the genus Taxus, we obtained the transcriptome profiles of T. chinensis grown under normal and low temperature (cold stress, 0°C conditions using Illumina Miseq sequencing. A transcriptome including 83,963 transcripts and 62,654 genes were assembled from 4.16 Gb of reads data. Comparative transcriptomic analysis identified 2,025 differently expressed (DE isoforms at p < 0.05, of which 1,437 were up-regulated by cold stress and 588 were down-regulated. Annotation of DE isoforms indicated that transcription factors (TFs in the MAPK signaling pathway and TF families of NAC, WRKY, bZIP, MYB, and ERF were transcriptionally activated. This might have been caused by the accumulation of secondary messengers, such as reactive oxygen species (ROS and Ca2+. While accumulation of ROS will have caused damages to cells, our results indicated that to adapt to low temperatures T. chinensis employed a series of mechanisms to minimize these damages. The mechanisms included: (i cold-enhanced expression of ROS deoxidant systems, such as peroxidase and phospholipid hydroperoxide glutathione peroxidase, to remove ROS. This was further confirmed by analyses showing increased activity of POD, SOD, and CAT under cold stress. (ii Activation of starch and sucrose metabolism, thiamine metabolism, and purine metabolism by cold-stress to produce metabolites which either protect cell organelles or lower the ROS content in cells. These processes are regulated by ROS signaling, as the “feedback” toward ROS accumulation.

  9. Differential response of hippocampal subregions to stress and learning.

    Directory of Open Access Journals (Sweden)

    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

  10. Correlation of EPO resistance with oxidative stress response and inflammatory response in patients with maintenance hemodialysis

    Directory of Open Access Journals (Sweden)

    Xiao-Hui Yan

    2017-08-01

    Full Text Available Objective: To study the correlation of erythropoietin (EPO resistance with oxidative stress response and inflammatory response in patients with maintenance hemodialysis. Methods: A total of 184 patients with end-stage renal disease who received maintenance hemodialysis in Shaanxi Provincial People’s Hospital between March 2015 and October 2016 were selected as dialysis group, 102 volunteers who received physical examination in Shaanxi Provincial People’s Hospital during the same period were selected as control group, the EPO resistance index was assessed, the median was calculated, and serum oxidative stress and inflammatory response indexes were detected. Results: Serum T-AOC, SOD and CAT levels in dialysis group were significantly lower than those in control group while MDA, AOPP, IFN-γ, HMGB-1, ICAM-1, IL-4 and IL-10 levels were significantly higher than those in control group; serum T-AOC, SOD and CAT levels in patients with high ERI were significantly lower than those in patients with low ERI while MDA, AOPP, IFN-γ, HMGB-1, ICAM-1, IL-4 and IL-10 levels were significantly higher than those in patients with low ERI. Conclusion: The degree of EPO resistance in patients with maintenance hemodialysis is closely related to the activation of oxidative stress response and inflammatory response.

  11. Integrated Stress Response Mediates Epithelial Injury in Mechanical Ventilation.

    Science.gov (United States)

    Dolinay, Tamas; Himes, Blanca E; Shumyatcher, Maya; Lawrence, Gladys Gray; Margulies, Susan S

    2017-08-01

    Ventilator-induced lung injury (VILI) is a severe complication of mechanical ventilation that can lead to acute respiratory distress syndrome. VILI is characterized by damage to the epithelial barrier with subsequent pulmonary edema and profound hypoxia. Available lung-protective ventilator strategies offer only a modest benefit in preventing VILI because they cannot impede alveolar overdistension and concomitant epithelial barrier dysfunction in the inflamed lung regions. There are currently no effective biochemical therapies to mitigate injury to the alveolar epithelium. We hypothesize that alveolar stretch activates the integrated stress response (ISR) pathway and that the chemical inhibition of this pathway mitigates alveolar barrier disruption during stretch and mechanical ventilation. Using our established rat primary type I-like alveolar epithelial cell monolayer stretch model and in vivo rat mechanical ventilation that mimics the alveolar overdistension seen in acute respiratory distress syndrome, we studied epithelial responses to mechanical stress. Our studies revealed that the ISR signaling pathway is a key modulator of epithelial permeability. We show that prolonged epithelial stretch and injurious mechanical ventilation activate the ISR, leading to increased alveolar permeability, cell death, and proinflammatory signaling. Chemical inhibition of protein kinase RNA-like endoplasmic reticulum kinase, an upstream regulator of the pathway, resulted in decreased injury signaling and improved barrier function after prolonged cyclic stretch and injurious mechanical ventilation. Our results provide new evidence that therapeutic targeting of the ISR can mitigate VILI.

  12. Biological response of Azospirillum spp. to different types of stress

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Sangoquiza Caiza

    2018-01-01

    Full Text Available Azospirillum is one of the most studied free-living rhizobacteria currently of great agricultural interest because of its ability to bind biological nitrogen and produce phytohormones. The present research aimed at the biological response of Azospirillum spp. facing different types of stress. For this purpose, the micro and macro morphological characterization of Azospirillum spp. And its biological response to stress temperature, pH, salinity. The results revealed that the isolates (C2, C3 and C4 of Azospirillum spp. Grow in greater abundance at temperatures between 28-38 °C and pH between 7-8. The C2 and C3 isolates showed good growth up to 3.5 % (m / v NaCl, whereas the C4 strain was less tolerant. These results have biotechnological applicability and are of great importance when defining and controlling the mass production conditions of Azospirillum spp. for future formulations as biofertilizer in several crops of interest in Ecuador.

  13. Evaluating physiological responses of plants to salinity stress

    KAUST Repository

    Negrão, Sónia

    2016-10-06

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments.

  14. Assessing Cd-induced stress from plant spectral response

    Science.gov (United States)

    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.

  15. Stress responsiveness predicts individual variation in mate selectivity.

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Antioxidant responses and cellular adjustments to oxidative stress.

    Science.gov (United States)

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-12-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases. Copyright © 2015. Published by Elsevier B.V.

  18. Influence of chemical peeling on the skin stress response system.

    Science.gov (United States)

    Kimura, Ayako; Kanazawa, Nobuo; Li, Hong-Jin; Yonei, Nozomi; Yamamoto, Yuki; Furukawa, Fukumi

    2012-07-01

    Skin stress response system (SSRS) involves corticotropin-releasing hormone (CRH) and proopiomelanocortin (POMC)-derived peptides, such as adrenocorticotropic hormone (ACTH), a-melanocyte-stimulating hormone (MSH) and b-endorphin that are locally generated in response to locally provided stressors or proinflammatory cytokines. This system would restrict tissue damage and restore local homoeostasis. Trichloroacetic acid (TCA) is one of the most widely used peeling agents and applied for cosmetic treatment of photodamaged skin. However, the biological mechanism responsible for TCA peeling has yet to be fully determined. While our investigation focused on the inflammation and wound healing pathways, in the recent study, we have examined involvement of the SSRS as the third pathway. Mostly depending on our findings that TCA peeling activates the SSRS by inducing the POMC expression of keratinocytes in the CRH-independent manner, together with the results reported by other researchers, we can say that the biological effect of POMC seems to be responsible for the TCA-induced epidermal SSRS activation. © 2012 John Wiley & Sons A/S.

  19. Transcriptional profiling in response to terminal drought stress reveals differential responses along the wheat genome

    Directory of Open Access Journals (Sweden)

    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

  20. Impulsivity and Stress Response in Pathological Gamblers During the Trier Social Stress Test.

    Science.gov (United States)

    Maniaci, G; Goudriaan, A E; Cannizzaro, C; van Holst, R J

    2018-03-01

    Gambling has been associated with increased sympathetic nervous system output and stimulation of the hypothalamic-pituitary-adrenal axis. However it is unclear how these systems are affected in pathological gambling. This study aimed to investigate the effect of the Trier Social Stress Test (TSST) on cortisol and on cardiac interbeat intervals in relation to impulsivity, in a sample of male pathological gamblers compared to healthy controls. In addition, we investigated the correlation between the TSST, duration of the disorder and impulsivity. A total of 35 pathological gamblers and 30 healthy controls, ranging from 19 to 58 years old and all male, participated in this study. Stress response was measured during and after the TSST by salivary cortisol and cardiac interbeat intervals; impulsivity was assessed with the Barratt Impulsiveness Scale (BIS-11). Exposure to the TSST produced a significant increase in salivary cortisol and interbeat intervals in both groups, without differences between groups. We found a negative correlation between baseline cortisol and duration of pathological gambling indicating that the longer the duration of the disorder the lower the baseline cortisol levels. Additionally, we found a main effect of impulsivity across groups on interbeat interval during the TSST, indicating an association between impulsivity and the intensity of the neurovegetative stress response during the TSST. Involvement of the hypothalamic-pituitary-adrenal axis in pathological gambling was confirmed together with evidence of a correlation between length of the disorder and diminished baseline cortisol levels. Impulsivity emerged as a personality trait expressed by pathological gamblers; however the neurovegetative response to the TSST, although associated with impulsivity, appeared to be independent of the presence of pathological gambling.

  1. Analysis of global gene expression profile of rice in response to methylglyoxal indicates its possible role as a stress signal molecule

    Directory of Open Access Journals (Sweden)

    Charanpreet eKaur

    2015-09-01

    Full Text Available Methylglyoxal (MG is a toxic metabolite produced primarily as a byproduct of glycolysis. Being a potent glycating agent, it can readily bind macromolecules like DNA, RNA or proteins, modulating their expression and activity. In plants, despite the known inhibitory effects of MG on growth and development, still limited information is available about the molecular mechanisms and response pathways elicited upon elevation in MG levels. To gain insight into the molecular basis of MG response, we have investigated changes in global gene expression profiles in rice upon exposure to exogenous MG using GeneChip microarrays. Initially, growth of rice seedlings was monitored in response to increasing MG concentrations which could retard plant growth in a dose-dependent manner. Upon exposure to 10 mM concentration of MG, a total of 1685 probe sets were up- or down-regulated by more than 1.5-fold in shoot tissues within 16 h. These were classified into ten functional categories. The genes involved in signal transduction such as, protein kinases and transcription factors, were significantly over-represented in the perturbed transcriptome, of which several are known to be involved in abiotic and biotic stress response indicating a cross-talk between MG-responsive and stress-responsive signal transduction pathways. Through in silico studies, we could predict 7-8 bp long conserved motif as a possible MG-responsive element (MGRE in the 1 kb upstream region of genes that were more than ten-fold up- or down-regulated in the analysis. Since several perturbations were found in signaling cascades in response to MG, we hereby suggest that it plays an important role in signal transduction probably acting as a stress signal molecule.

  2. Phloem small RNAs, nutrient stress responses, and systemic mobility

    Directory of Open Access Journals (Sweden)

    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

  3. Emotional coping response to hassles and stress experienced in wilderness settings

    Science.gov (United States)

    Rudy M. Schuster; W. E. Hammitt

    2003-01-01

    Stress/coping theory was used to understand recreationists' appraisal of stressful situations, coping processes, and the outcomes of the process. Specifically, stress was conceptualized as hassles in recreation settings. Specifically, the objective of this paper was to discuss the emotion focused coping response of visitors to stress encountered while on a...

  4. The Warfighter's Stress Response: Telemetric and Noninvasive Assessment

    National Research Council Canada - National Science Library

    O'Donnell, Amanda

    2002-01-01

    ... during stress, experience less burnout, demonstrate better navigational skills, and are able to stay physiologically calmer during potentially life-threatening events and during uncontrollable stress...

  5. Plasma omega 3 polyunsaturated fatty acid status and monounsaturated fatty acids are altered by chronic social stress and predict endocrine responses to acute stress in titi monkeys

    Science.gov (United States)

    Disturbances in fatty acid (FA) metabolism may link chronic psychological stress, endocrine responsiveness, and psychopathology. Therefore, lipid metabolome-wide responses and their relationships with endocrine (cortisol; insulin; adiponectin) responsiveness to acute stress (AS) were assessed in a ...

  6. Response of a multi-stressed Mediterranean river to future climate and socio-economic scenarios.

    Science.gov (United States)

    Stefanidis, Konstantinos; Panagopoulos, Yiannis; Mimikou, Maria

    2018-06-15

    Streams and rivers are among the most threatened ecosystems in Europe due to the combined effects of multiple pressures related to anthropogenic activities. Particularly in the Mediterranean region, changes in hydromorphology along with increased nutrient loadings are known to affect the ecological functions and ecosystem services of streams and rivers with the anticipated climate change being likely to further impair their functionality and structure. In this study, we investigated the combined effects of agricultural driven stressors on the ecology and delivered services of the Pinios river basin in Greece under three future world scenarios developed within the EU funded MARS project. Scenarios are based on combinations of Representative Concentration Pathways and Shared Socioeconomic Pathways and refer to early century (2030) and mid-century (2060) representing future climate worlds with particular socioeconomic characteristics. To assess the responses of ecological and ecosystem service indicators to the scenarios we first simulated hydrology and water quality in Pinios with a process-based model. Simulated abiotic stressor parameters (predictors) were linked to two biotic indicators, the macroinvertebrate indicators ASPT and EPT, with empirical modelling based on boosted regression trees and general linear models. Our results showed that the techno world scenario driven by fast economic growth and intensive exploitation of energy resources had the largest impact on both the abiotic status (nutrient loads and concentrations in water) and the biotic indicators. In contrast, the predicted changes under the other two future worlds, consensus and fragmented, were more diverse and were mostly dictated by the projected climate. This work showed that the future scenarios, especially the mid-century ones, had significant impact on both abiotic status and biotic responses underpinning the need for implementing catchment management practices able to mitigate the

  7. Adaptive stress response to menadione-induced oxidative stress in Saccharomyces cerevisiae KNU5377.

    Science.gov (United States)

    Kim, Il-Sup; Sohn, Ho-Yong; Jin, Ingnyol

    2011-10-01

    The molecular mechanisms involved in the ability of yeast cells to adapt and respond to oxidative stress are of great interest to the pharmaceutical, medical, food, and fermentation industries. In this study, we investigated the time-dependent, cellular redox homeostasis ability to adapt to menadione-induced oxidative stress, using biochemical and proteomic approaches in Saccharomyces cerevisiae KNU5377. Time-dependent cell viability was inversely proportional to endogenous amounts of ROS measured by a fluorescence assay with 2',7'-dichlorofluorescin diacetate (DCFHDA), and was hypersensitive when cells were exposed to the compound for 60 min. Morphological changes, protein oxidation and lipid peroxidation were also observed. To overcome the unfavorable conditions due to the presence of menadione, yeast cells activated a variety of cell rescue proteins including antioxidant enzymes, molecular chaperones, energy-generating metabolic enzymes, and antioxidant molecules such as trehalose. Thus, these results show that menadione causes ROS generation and high accumulation of cellular ROS levels, which affects cell viability and cell morphology and there is a correlation between resistance to menadione and the high induction of cell rescue proteins after cells enter into this physiological state, which provides a clue about the complex and dynamic stress response in yeast cells.

  8. Infants, Mothers, and Dyadic Contributions to Stability and Prediction of Social Stress Response at 6 Months

    Science.gov (United States)

    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…

  9. Comprehensive phenotypic analysis of rice (Oryza sativa) response to salinity stress

    KAUST Repository

    Pires, Inê s S.; Negrã o, Só nia; Oliveira, M. Margarida; Purugganan, Michael D.

    2015-01-01

    affected by salt stress in rice, which puts in question the importance of K+/Na+ when analyzing rice salt stress response. Not only do our results contribute to improve our global understanding of salt stress response in an important crop, but we also use

  10. Intracellular proteins produced by mammalian cells in response to environmental stress

    Science.gov (United States)

    Goochee, Charles F.; Passini, Cheryl A.

    1988-01-01

    The nature of the response of mammalian cells to environmental stress is examined by reviewing results of studies where cultured mouse L cells and baby hamster kidney cells were exposed to heat shock and the synthesis of heat-shock proteins and stress-response proteins (including HSP70, HSC70, HSP90, ubiquitin, and GRP70) in stressed and unstressed cells was evaluated using 2D-PAGE. The intracellular roles of the individual stress response proteins are discussed together with the regulation of the stress response system.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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 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 and ABRE-binding factor 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 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 TFs 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.

  13. Acid and base stress and transcriptomic responses in Bacillus subtilis.

    Science.gov (United States)

    Wilks, Jessica C; Kitko, Ryan D; Cleeton, Sarah H; Lee, Grace E; Ugwu, Chinagozi S; Jones, Brian D; BonDurant, Sandra S; Slonczewski, Joan L

    2009-02-01

    Acid and base environmental stress responses were investigated in Bacillus subtilis. B. subtilis AG174 cultures in buffered potassium-modified Luria broth were switched from pH 8.5 to pH 6.0 and recovered growth rapidly, whereas cultures switched from pH 6.0 to pH 8.5 showed a long lag time. Log-phase cultures at pH 6.0 survived 60 to 100% at pH 4.5, whereas cells grown at pH 7.0 survived base induced adaptation to a more extreme acid or base, respectively. Expression indices from Affymetrix chip hybridization were obtained for 4,095 protein-encoding open reading frames of B. subtilis grown at external pH 6, pH 7, and pH 9. Growth at pH 6 upregulated acetoin production (alsDS), dehydrogenases (adhA, ald, fdhD, and gabD), and decarboxylases (psd and speA). Acid upregulated malate metabolism (maeN), metal export (czcDO and cadA), oxidative stress (catalase katA; OYE family namA), and the SigX extracytoplasmic stress regulon. Growth at pH 9 upregulated arginine catabolism (roc), which generates organic acids, glutamate synthase (gltAB), polyamine acetylation and transport (blt), the K(+)/H(+) antiporter (yhaTU), and cytochrome oxidoreductases (cyd, ctaACE, and qcrC). The SigH, SigL, and SigW regulons were upregulated at high pH. Overall, greater genetic adaptation was seen at pH 9 than at pH 6, which may explain the lag time required for growth shift to high pH. Low external pH favored dehydrogenases and decarboxylases that may consume acids and generate basic amines, whereas high external pH favored catabolism-generating acids.

  14. Development of a macrophyte-based index of biotic integrity for Minnesota lakes

    Science.gov (United States)

    Beck, M.W.; Hatch, L.K.; Vondracek, B.; Valley, R.D.

    2010-01-01

    Traditional approaches for managing aquatic resources have often failed to account for effects of anthropogenic disturbances on biota that are not directly reflected by chemical and physical proxies of environmental condition. The index of biotic integrity (IBI) is a potentially effective assessment method to integrate ecological, functional, and structural aspects of aquatic systems. A macrophyte-based IBI was developed for Minnesota lakes to assess the ability of aquatic plant communities to indicate environmental condition. The index was developed using quantitative point intercept vegetation surveys for 97 lakes that represent a range of limnological and watershed characteristics. We followed an approach similar to that used in Wisconsin to develop the aquatic macrophyte community index (AMCI). Regional adaptation of the AMCI required the identification of species representative of macrophyte communities in Minnesota. Metrics and scaling methods were also substantially modified to produce a more empirically robust index. Regression analyses indicated that IBI scores reflected statewide differences in lake trophic state (R2 = 0.57, F = 130.3, df = 1, 95, p indicated a unique response of the IBI to human-induced stress separate from a response to natural lake characteristics. The IBI was minimally affected by differences in sample point density as indicated by Monte Carlo analyses of reduced sampling effort. Our analysis indicates that a macrophyte IBI calibrated for Minnesota lakes could be useful for identifying differences in environmental condition attributed to human-induced stress gradients. ?? 2010 Elsevier Ltd.

  15. Acid Stress Response Mechanisms of Group B Streptococci

    Directory of Open Access Journals (Sweden)

    Sarah Shabayek

    2017-09-01

    Full Text Available Group B streptococcus (GBS is a leading cause of neonatal mortality and morbidity in the United States and Europe. It is part of the vaginal microbiota in up to 30% of pregnant women and can be passed on to the newborn through perinatal transmission. GBS has the ability to survive in multiple different host niches. The pathophysiology of this bacterium reveals an outstanding ability to withstand varying pH fluctuations of the surrounding environments inside the human host. GBS host pathogen interations include colonization of the acidic vaginal mucosa, invasion of the neutral human blood or amniotic fluid, breaching of the blood brain barrier as well as survival within the acidic phagolysosomal compartment of macrophages. However, investigations on GBS responses to acid stress are limited. Technologies, such as whole genome sequencing, genome-wide transcription and proteome mapping facilitate large scale identification of genes and proteins. Mechanisms enabling GBS to cope with acid stress have mainly been studied through these techniques and are summarized in the current review

  16. Albumin Antioxidant Response to Stress in Diabetic Nephropathy Progression

    Science.gov (United States)

    Medina-Navarro, Rafael; Corona-Candelas, Itzia; Barajas-González, Saúl; Díaz-Flores, Margarita; Durán-Reyes, Genoveva

    2014-01-01

    Background A new component of the protein antioxidant capacity, designated Response Surplus (RS), was recently described. A major feature of this component is the close relationship between protein antioxidant capacity and molecular structure. Oxidative stress is associated with renal dysfunction in patients with renal failure, and plasma albumin is the target of massive oxidation in nephrotic syndrome and diabetic nephropathy. The aim of the present study was to explore the albumin redox state and the RS component of human albumin isolated from diabetic patients with progressive renal damage. Methods/Principal Findings Serum aliquots were collected and albumin isolated from 125 diabetic patients divided into 5 groups according to their estimated glomerular filtration rate (GFR). In addition to clinical and biochemical variables, the albumin redox state, including antioxidant capacity, thiol group content, and RS component, were evaluated. The albumin antioxidant capacity and thiol group content were reciprocally related to the RS component in association with GFR reduction. The GFR decline and RS component were significantly negatively correlated (R = –0.83, palbumin to stress in relation to the progression of diabetic renal disease was evaluated. The findings confirm that the albumin molecular structure is closely related to its redox state, and is a key factor in the progression of diabetes nephropathy. PMID:25187963

  17. LKB1 promotes metabolic flexibility in response to energy stress.

    Science.gov (United States)

    Parker, Seth J; Svensson, Robert U; Divakaruni, Ajit S; Lefebvre, Austin E; Murphy, Anne N; Shaw, Reuben J; Metallo, Christian M

    2017-09-01

    The Liver Kinase B1 (LKB1) tumor suppressor acts as a metabolic energy sensor to regulate AMP-activated protein kinase (AMPK) signaling and is commonly mutated in various cancers, including non-small cell lung cancer (NSCLC). Tumor cells deficient in LKB1 may be uniquely sensitized to metabolic stresses, which may offer a therapeutic window in oncology. To address this question we have explored how functional LKB1 impacts the metabolism of NSCLC cells using 13 C metabolic flux analysis. Isogenic NSCLC cells expressing functional LKB1 exhibited higher flux through oxidative mitochondrial pathways compared to those deficient in LKB1. Re-expression of LKB1 also increased the capacity of cells to oxidize major mitochondrial substrates, including pyruvate, fatty acids, and glutamine. Furthermore, LKB1 expression promoted an adaptive response to energy stress induced by anchorage-independent growth. Finally, this diminished adaptability sensitized LKB1-deficient cells to combinatorial inhibition of mitochondrial complex I and glutaminase. Together, our data implicate LKB1 as a major regulator of adaptive metabolic reprogramming and suggest synergistic pharmacological strategies for mitigating LKB1-deficient NSCLC tumor growth. Copyright © 2016. Published by Elsevier Inc.

  18. The CarERF genes in chickpea (Cicer arietinum L.) and the identification of CarERF116 as abiotic stress responsive transcription factor.

    Science.gov (United States)

    Deokar, Amit A; Kondawar, Vishwajith; Kohli, Deshika; Aslam, Mohammad; Jain, Pradeep K; Karuppayil, S Mohan; Varshney, Rajeev K; Srinivasan, Ramamurthy

    2015-01-01

    The AP2/ERF family is one of the largest transcription factor gene families that are involved in various plant processes, especially in response to biotic and abiotic stresses. Complete genome sequences of one of the world's most important pulse crops chickpea (Cicer arietinum L.), has provided an important opportunity to identify and characterize genome-wide ERF genes. In this study, we identified 120 putative ERF genes from chickpea. The genomic organization of the chickpea ERF genes suggested that the gene family might have been expanded through the segmental duplications. The 120 member ERF family was classified into eleven distinct groups (I-X and VI-L). Transcriptional factor CarERF116, which is differentially expressed between drought tolerant and susceptible chickpea cultivar under terminal drought stress has been identified and functionally characterized. The CarERF116 encodes a putative protein of 241 amino acids and classified into group IX of ERF family. An in vitro CarERF116 protein-DNA binding assay demonstrated that CarERF116 protein specifically interacts with GCC box. We demonstrate that CarERF116 is capable of transactivation activity of and show that the functional transcriptional domain lies at the C-terminal region of the CarERF116. In transgenic Arabidopsis plants overexpressing CarERF116, significant up-regulation of several stress related genes were observed. These plants also exhibit resistance to osmotic stress and reduced sensitivity to ABA during seed germination. Based on these findings, we conclude that CarERF116 is an abiotic stress responsive gene, which plays an important role in stress tolerance. In addition, the present study leads to genome-wide identification and evolutionary analyses of chickpea ERF gene family, which will facilitate further research on this important group of genes and provides valuable resources for comparative genomics among the grain legumes.

  19. Listeria monocytogenes response regulators important for stress tolerance and pathogenesis

    DEFF Research Database (Denmark)

    Kallipolitis, B H; Ingmer, H

    2001-01-01

    Environmental sensing by two-component signal transduction systems is likely to play a role for growth and survival of Listeria monocytogenes both during transmission in food products and within a host organism. Two-component systems typically consist of a membrane-associated sensor histidine...... kinase and a gene regulatory protein, the response regulator (RR). We have identified seven putative RR genes in L. monocytogenes LO28 by PCR using degenerate oligonucleotide primers. By insertional inactivation we obtained data suggesting that three of the putative RRs contribute to the pathogenicity...... of L. monocytogenes in mice. Strikingly, the mutants that were attenuated in virulence also had a decreased ability to grow in the presence of various stress conditions potentially encountered in an infection process. Thus, our data point to a connection between the ability of the putative two...

  20. Design, engineering and utility of biotic games.

    Science.gov (United States)

    Riedel-Kruse, Ingmar H; Chung, Alice M; Dura, Burak; Hamilton, Andrea L; Lee, Byung C

    2011-01-07

    Games are a significant and defining part of human culture, and their utility beyond pure entertainment has been demonstrated with so-called 'serious games'. Biotechnology--despite its recent advancements--has had no impact on gaming yet. Here we propose the concept of 'biotic games', i.e., games that operate on biological processes. Utilizing a variety of biological processes we designed and tested a collection of games: 'Enlightenment', 'Ciliaball', 'PAC-mecium', 'Microbash', 'Biotic Pinball', 'POND PONG', 'PolymerRace', and 'The Prisoner's Smellemma'. We found that biotic games exhibit unique features compared to existing game modalities, such as utilizing biological noise, providing a real-life experience rather than virtual reality, and integrating the chemical senses into play. Analogous to video games, biotic games could have significant conceptual and cost-reducing effects on biotechnology and eventually healthcare; enable volunteers to participate in crowd-sourcing to support medical research; and educate society at large to support personal medical decisions and the public discourse on bio-related issues.

  1. CaMKII determines mitochondrial stress responses in heart

    Science.gov (United States)

    Joiner, Mei-ling A.; Koval, Olha M.; Jingdong, Li; He, B. Julie; Allamargot, Chantal; Gao, Zhan; Luczak, Elizabeth D.; Hall, Duane D.; Fink, Brian D.; Chen, Biyi; Yang, Jinying; Moore, Steven A.; Scholz, Thomas D.; Strack, Stefan; Mohler, Peter J.; Sivitz, William I.; Song, Long-Sheng; Anderson, Mark E.

    2012-01-01

    Myocardial cell death is initiated by excessive mitochondrial Ca2+ entry, causing Ca2+ overload, mitochondrial permeability transition pore (mPTP) opening and dissipation of the mitochondrial inner membrane potential (ΔΨm)1,2. However, the signaling pathways that control mitochondrial Ca2+ entry through the inner membrane mitochondrial Ca2+ uniporter (MCU)3–5 are not known. The multifunctional Ca2+ and calmodulin-dependent protein kinase II (CaMKII) is activated in ischemia reperfusion (I/R), myocardial infarction (MI) and neurohumoral injury, common causes of myocardial death and heart failure, suggesting CaMKII could couple disease stress to mitochondrial injury. Here we show that CaMKII promotes mPTP opening and myocardial death by increasing MCU current (IMCU). Mitochondrial-targeted CaMKII inhibitory protein or cyclosporin A (CsA), an mPTP antagonist with clinical efficacy in I/R injury6, equivalently prevent mPTP opening, ΔΨm deterioration and diminish mitochondrial disruption and programmed cell death in response to I/R injury. Mice with myocardial and mitochondrial-targeted CaMKII inhibition are resistant to I/R injury, MI and neurohumoral injury, suggesting pathological actions of CaMKII are substantially mediated by increasing IMCU. Our findings identify CaMKII activity as a central mechanism for mitochondrial Ca2+ entry and suggest mitochondrial-targeted CaMKII inhibition could prevent or reduce myocardial death and heart failure dysfunction in response to common experimental forms of pathophysiological stress. PMID:23051746

  2. Emotionally Responsive Wearable Technology and Stress Detection for Affective Disorders.

    Science.gov (United States)

    Tillotson, Jenny

    2017-09-01

    As humans, we are born with no knowledge of odour. Our sense of smell is linked directly to the limbic system, the emotional part of our brain responsible for memory and behaviour, and therefore, our individual sense of smell is based purely on life's deep experiences and impressions. The roots of "Aromatherapy" can be traced back more than 3,500 years, to a time when essential oils were first recorded in human history for their therapeutic and medicinal properties. However, in the 21 st century, it remains one of the most contr