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Sample records for abiotic stress responses

  1. 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), ...

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

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    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.

  3. Nitric Oxide Signaling in Plant Responses to Abiotic Stresses

    Institute of Scientific and Technical Information of China (English)

    Weihua Qiao; LiuMin Fan

    2008-01-01

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

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

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    Ines Ben Rejeb

    2014-10-01

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

  5. Involvement of Histone Modifications in Plant Abiotic Stress Responses

    Institute of Scientific and Technical Information of China (English)

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

    2013-01-01

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

  6. 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...... through ubiquitination. The wide range of biotic and abiotic stresses that affect crop plants limits agricultural production....... 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...

  7. Cell Wall Metabolism in Response to Abiotic Stress

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    Hyacinthe Le Gall

    2015-02-01

    Full Text Available 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.

  8. Genes Acting on Transcriptional Control during Abiotic Stress Responses

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    Glacy Jaqueline da Silva

    2014-01-01

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

  9. The Plant Heat Stress Transcription Factors (HSFs): Structure, Regulation, and Function in Response to Abiotic Stresses.

    Science.gov (United States)

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Luo, De-Xu; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-01-01

    Abiotic stresses such as high temperature, salinity, and drought adversely affect the survival, growth, and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological, and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs), including heat stress transcription factors (HSFs). HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps). In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention.

  10. The plant heat stress transcription factors (HSFs: structure, regulation and function in response to abiotic stresses

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    Meng eGuo

    2016-02-01

    Full Text Available Abiotic stresses such as high temperature, salinity and drought adversely affect the survival, growth and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs, including heat stress transcription factors (HSFs. HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps. In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention.

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

    Science.gov (United States)

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

    2016-08-01

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

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

    Science.gov (United States)

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

    2016-03-01

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

  13. Polyamines in response to abiotic stress tolerance through transgenic approaches

    Science.gov (United States)

    Pathak, Malabika Roy; Teixeira da Silva, Jaime A; Wani, Shabir H

    2014-01-01

    The distribution, growth, development and productivity of crop plants are greatly affected by various abiotic stresses. Worldwide, sustainable crop productivity is facing major challenges caused by abiotic stresses by reducing the potential yield in crop plants by as much as 70%. Plants can generally adapt to one or more environmental stresses to some extent. Physiological and molecular studies at transcriptional, translational, and transgenic plant levels have shown the pronounced involvement of naturally occurring plant polyamines (PAs), in controlling, conferring, and modulating abiotic stress tolerance in plants. PAs are small, low molecular weight, non-protein polycations at physiological pH, that are present in all living organisms, and that have strong binding capacity to negatively charged DNA, RNA, and different protein molecules. They play an important role in plant growth and development by controlling the cell cycle, acting as cell signaling molecules in modulating plant tolerance to a variety of abiotic stresses. The commonly known PAs, putrescine, spermidine, and spermine tend to accumulate together accompanied by an increase in the activities of their biosynthetic enzymes under a range of environmental stresses. PAs help plants to combat stresses either directly or by mediating a signal transduction pathway, as shown by molecular cloning and expression studies of PA biosynthesis-related genes, knowledge of the functions of PAs, as demonstrated by developmental studies, and through the analysis of transgenic plants carrying PA genes. This review highlights how PAs in higher plants act during environmental stress and how transgenic strategies have improved our understanding of the molecular mechanisms at play. PMID:24710064

  14. The role of transcriptional coactivator ADA2b in Arabidopsis abiotic stress responses.

    Science.gov (United States)

    Vlachonasios, Konstantinos E; Kaldis, Athanasios; Nikoloudi, Adriana; Tsementzi, Despoina

    2011-10-01

    Plant growth and crop production can be greatly affected by common environmental stresses such as drought, high salinity and low temperatures. Gene expression is affected by several abiotic stresses. Stress-inducible genes are regulated by transcription factors and epigenetic mechanisms such as histone modifications. In this Mini-Review, we have explored the role of transcriptional adaptor ADA2b in Arabidopsis responses to abiotic stress. ADA2b is required for the expression of genes involved in abiotic stress either by controlling H3 and H4 acetylation in the case of salt stress or affecting nucleosome occupancy in low temperatures response.

  15. 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 phytoho......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...

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

    Institute of Scientific and Technical Information of China (English)

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

    2007-01-01

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

  17. Functions and mechanisms of the CBL-CIPK signaling system in plant response to abiotic stress

    Institute of Scientific and Technical Information of China (English)

    Ruifen Li; Junwen Zhang; Jianhua Wei; Hongzhi Wang; Yanzhen Wang; Rongcai Ma

    2009-01-01

    To cope with environmental stimuli, plants have evolved precise regulatory mechanisms to perceive, transduce and respond to abiotic stresses that can negatively affect growth and development. The CBL-CIPK signaling system is a newly emerging plant-specific and Ca2+-dependent network mediating abiotic stress tolerance. CBLs may sense a Ca2+ signature triggered by abiotic stresses, and have specific interactions with novel CIPK-type kinases after binding Ca2+. The CBL/CIPK complexes may post-translationally phosphory-late downstream target proteins to regulate abiotic stress tolerance in a cell or tissue-specific manner. In some cases transcription factors are induced to activate stress-responsive genes that control adaptation reactions. The CBL-CIPK signaling system exhibits specificity, diversity and complexity. Meanwhile, cross talk also exists in the CBL-CIPK signaling. To date, significant progress has been made in the role of the CBL-CIPK signaling system in responding to salt, low K+ and to high pH, which will provide a fast and efficient method of molecular design breeding combined with the CBL/CIPK engineering of crop plants, for enhanced tolerance to abiotic stresses. How-ever, more CBL/CIPK components remain to be identified, particularly from specific plants that grow in conditions with abiotic stress, and the specificity of their abiotic stress signaling will need to be dissected.

  18. 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

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

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    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.

  20. Identification of Abiotic Stress Responsive Genes from Indian High Altitude Lepidium latifolium L. (Short Communication

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    Sanjay Mohan Gupta

    2012-09-01

    Full Text Available Abiotic stresses are major environmental factors that periodically account for significant loss in crop productivity. In order to improve the abiotic stress tolerance in vegetable crops through transgenic approaches, authors isolated and cloned six up-regulated, LlaDREB1b (JN214345, LlaGPAT (JN398166, LlaNAC (FJ423495, LlaCIPK (FJ423496, LlaPR5 (GQ853409 and LlaIPK (FJ487575 and two down-regulated LlaRan (JN214347 and LlaDRT (JN214346 abiotic stress responsive genes from Indian high altitude Lepidium latifolium L. plant that that may be used for abiotic stress-tolerance engineering upon functional validation.Defence Science Journal, 2012, 62(5, pp.315-318, DOI:http://dx.doi.org/10.14429/dsj.62.1495

  1. Molecular and physiological responses to abiotic stress in forest trees and their relevance to tree improvement.

    Science.gov (United States)

    Harfouche, Antoine; Meilan, Richard; Altman, Arie

    2014-11-01

    Abiotic stresses, such as drought, salinity and cold, are the major environmental stresses that adversely affect tree growth and, thus, forest productivity, and play a major role in determining the geographic distribution of tree species. Tree responses and tolerance to abiotic stress are complex biological processes that are best analyzed at a systems level using genetic, genomic, metabolomic and phenomic approaches. This will expedite the dissection of stress-sensing and signaling networks to further support efficient genetic improvement programs. Enormous genetic diversity for stress tolerance exists within some forest-tree species, and due to advances in sequencing technologies the molecular genetic basis for this diversity has been rapidly unfolding in recent years. In addition, the use of emerging phenotyping technologies extends the suite of traits that can be measured and will provide us with a better understanding of stress tolerance. The elucidation of abiotic stress-tolerance mechanisms will allow for effective pyramiding of multiple tolerances in a single tree through genetic engineering. Here we review recent progress in the dissection of the molecular basis of abiotic stress tolerance in forest trees, with special emphasis on Populus, Pinus, Picea, Eucalyptus and Quercus spp. We also outline practices that will enable the deployment of trees engineered for abiotic stress tolerance to land owners. Finally, recommendations for future work are discussed.

  2. Arabidopsis microRNA expression regulation in a wide range of abiotic stress responses.

    Science.gov (United States)

    Barciszewska-Pacak, Maria; Milanowska, Kaja; Knop, Katarzyna; Bielewicz, Dawid; Nuc, Przemyslaw; Plewka, Patrycja; Pacak, Andrzej M; Vazquez, Franck; Karlowski, Wojciech; Jarmolowski, Artur; Szweykowska-Kulinska, Zofia

    2015-01-01

    Arabidopsis microRNA expression regulation was studied in a wide array of abiotic stresses such as drought, heat, salinity, copper excess/deficiency, cadmium excess, and sulfur deficiency. A home-built RT-qPCR mirEX platform for the amplification of 289 Arabidopsis microRNA transcripts was used to study their response to abiotic stresses. Small RNA sequencing, Northern hybridization, and TaqMan® microRNA assays were performed to study the abundance of mature microRNAs. A broad response on the level of primary miRNAs (pri-miRNAs) was observed. However, stress response at the level of mature microRNAs was rather confined. The data presented show that in most instances, the level of a particular mature miRNA could not be predicted based on the level of its pri-miRNA. This points to an essential role of posttranscriptional regulation of microRNA expression. New Arabidopsis microRNAs responsive to abiotic stresses were discovered. Four microRNAs: miR319a/b, miR319b.2, and miR400 have been found to be responsive to several abiotic stresses and thus can be regarded as general stress-responsive microRNA species.

  3. Comprehensive Analysis Suggests Overlapping Expression of Rice ONAC Transcription Factors in Abiotic and Biotic Stress Responses

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    Lijun Sun

    2015-02-01

    Full Text Available NAC (NAM/ATAF/CUC transcription factors comprise a large plant-specific gene family that contains more than 149 members in rice. Extensive studies have revealed that NAC transcription factors not only play important roles in plant growth and development, but also have functions in regulation of responses to biotic and abiotic stresses. However, biological functions for most of the members in the NAC family remain unknown. In this study, microarray data analyses revealed that a total of 63 ONAC genes exhibited overlapping expression patterns in rice under various abiotic (salt, drought, and cold and biotic (infection by fungal, bacterial, viral pathogens, and parasitic plants stresses. Thirty-eight ONAC genes exhibited overlapping expression in response to any two abiotic stresses, among which 16 of 30 selected ONAC genes were upregulated in response to exogenous ABA. Sixty-five ONAC genes showed overlapping expression patterns in response to any two biotic stresses. Results from the present study suggested that members of the ONAC genes with overlapping expression pattern may have pleiotropic biological functions in regulation of defense response against different abiotic and biotic stresses, which provide clues for further functional analysis of the ONAC genes in stress tolerance and pathogen resistance.

  4. Comprehensive analysis suggests overlapping expression of rice ONAC transcription factors in abiotic and biotic stress responses.

    Science.gov (United States)

    Sun, Lijun; Huang, Lei; Hong, Yongbo; Zhang, Huijuan; Song, Fengming; Li, Dayong

    2015-01-01

    NAC (NAM/ATAF/CUC) transcription factors comprise a large plant-specific gene family that contains more than 149 members in rice. Extensive studies have revealed that NAC transcription factors not only play important roles in plant growth and development, but also have functions in regulation of responses to biotic and abiotic stresses. However, biological functions for most of the members in the NAC family remain unknown. In this study, microarray data analyses revealed that a total of 63 ONAC genes exhibited overlapping expression patterns in rice under various abiotic (salt, drought, and cold) and biotic (infection by fungal, bacterial, viral pathogens, and parasitic plants) stresses. Thirty-eight ONAC genes exhibited overlapping expression in response to any two abiotic stresses, among which 16 of 30 selected ONAC genes were upregulated in response to exogenous ABA. Sixty-five ONAC genes showed overlapping expression patterns in response to any two biotic stresses. Results from the present study suggested that members of the ONAC genes with overlapping expression pattern may have pleiotropic biological functions in regulation of defense response against different abiotic and biotic stresses, which provide clues for further functional analysis of the ONAC genes in stress tolerance and pathogen resistance. PMID:25690040

  5. Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and resistance mechanism

    NARCIS (Netherlands)

    Kissoudis, Christos; Sri Sunarti, Sri; De Wiel, Van Clemens; Visser, Richard G.F.; Linden, van der Gerard; Bai, Yuling

    2016-01-01

    Stress conditions in agricultural ecosystems can occur at variable intensities. Different resistance mechanisms against abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effec

  6. Supplementary data: Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and mechanism of resistance

    NARCIS (Netherlands)

    Kissoudis, C.; Sri Sunarti, Sri; Wiel, van de C.C.M.; Visser, R.G.F.; Linden, van der C.G.; Bai, Y.

    2016-01-01

    Stress conditions in agricultural ecosystems can occur in variable intensities. Different resistance mechanisms to abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effect of

  7. Natural variation in abiotic stress responsive gene expression and local adaptation to climate in Arabidopsis thaliana.

    Science.gov (United States)

    Lasky, Jesse R; Des Marais, David L; Lowry, David B; Povolotskaya, Inna; McKay, John K; Richards, James H; Keitt, Timothy H; Juenger, Thomas E

    2014-09-01

    Gene expression varies widely in natural populations, yet the proximate and ultimate causes of this variation are poorly known. Understanding how variation in gene expression affects abiotic stress tolerance, fitness, and adaptation is central to the field of evolutionary genetics. We tested the hypothesis that genes with natural genetic variation in their expression responses to abiotic stress are likely to be involved in local adaptation to climate in Arabidopsis thaliana. Specifically, we compared genes with consistent expression responses to environmental stress (expression stress responsive, "eSR") to genes with genetically variable responses to abiotic stress (expression genotype-by-environment interaction, "eGEI"). We found that on average genes that exhibited eGEI in response to drought or cold had greater polymorphism in promoter regions and stronger associations with climate than those of eSR genes or genomic controls. We also found that transcription factor binding sites known to respond to environmental stressors, especially abscisic acid responsive elements, showed significantly higher polymorphism in drought eGEI genes in comparison to eSR genes. By contrast, eSR genes tended to exhibit relatively greater pairwise haplotype sharing, lower promoter diversity, and fewer nonsynonymous polymorphisms, suggesting purifying selection or selective sweeps. Our results indicate that cis-regulatory evolution and genetic variation in stress responsive gene expression may be important mechanisms of local adaptation to climatic selective gradients.

  8. Multifaceted roles of aquaporins as molecular conduits in plant responses to abiotic stresses.

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    Srivastava, Ashish Kumar; Penna, Suprasanna; Nguyen, Dong Van; Tran, Lam-Son Phan

    2016-06-01

    Abiotic stress has become a challenge to food security due to occurrences of climate change and environmental degradation. Plants initiate molecular, cellular and physiological changes to respond and adapt to various types of abiotic stress. Understanding of plant response mechanisms will aid in strategies aimed at improving stress tolerance in crop plants. One of the most common and early symptoms associated with these stresses is the disturbance in plant-water homeostasis, which is regulated by a group of proteins called "aquaporins". Aquaporins constitute a small family of proteins which are classified further on the basis of their localization, such as plasma membrane intrinsic proteins, tonoplast intrinsic proteins, nodulin26-like intrinsic proteins (initially identified in symbiosomes of legumes but also found in the plasma membrane and endoplasmic reticulum), small basic intrinsic proteins localized in ER (endoplasmic reticulum) and X intrinsic proteins present in plasma membrane. Apart from water, aquaporins are also known to transport CO2, H2O2, urea, ammonia, silicic acid, arsenite and wide range of small uncharged solutes. Besides, aquaporins also function to modulate abiotic stress-induced signaling. Such kind of versatile functions has made aquaporins a suitable candidate for development of transgenic plants with increased tolerance toward different abiotic stress. Toward this endeavor, the present review describes the versatile functions of aquaporins in water uptake, nutrient balancing, long-distance signal transfer, nutrient/heavy metal acquisition and seed development. Various functional genomic studies showing the potential of specific aquaporin isoforms for enhancing plant abiotic stress tolerance are summarized and future research directions are given to design stress-tolerant crops. PMID:25430890

  9. INDIVIDUAL AND POPULATION RESPONSES TO ABIOTIC STRESSES IN ITALIAN RYEGRASS

    Science.gov (United States)

    Expected changes in environmental factors will alter productivity of agroecosystems and influence the distribution of agricultural pests. In addition to the natural factors that cause stress, humans introduce chemical pesticides into the agricultural environment. Weeds persist in...

  10. 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

  11. 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

  12. Proteomic studies of the abiotic stresses response in model moss—Physcomitrella patens

    Directory of Open Access Journals (Sweden)

    Xiaoqin eWang

    2012-11-01

    Full Text Available Moss species Physcomitrella patens (P. patens has been used as a model system in plant science for several years, because it has a short life cycle and is easy to be handled. With the completion of its genome sequencing, more and more proteomic analyses were conducted to study the mechanisms of P. patens abiotic stress resistance. It can be concluded from these studies that abiotic stresses could lead to the repression of photosynthesis and enhancement of respiration in P. patens, although different stresses could also result in specific responses. Comparative analysis showed that the responses to drought and salinity were very similar to that of ABA, while the response to cold was quite different from these three. Based on previous studies, it is proposed that sub-proteomic studies on organelles or protein modifications, as well as functional characterization of those candidate proteins identified from proteomic studies will help us to further understand the mechanisms of abiotic stress resistance in P. patens.

  13. Methylglyoxal: An Emerging Signaling Molecule in Plant Abiotic Stress Responses and Tolerance

    Science.gov (United States)

    Hoque, Tahsina S.; Hossain, Mohammad A.; Mostofa, Mohammad G.; Burritt, David J.; Fujita, Masayuki; Tran, Lam-Son P.

    2016-01-01

    The oxygenated short aldehyde methylglyoxal (MG) is produced in plants as a by-product of a number of metabolic reactions, including elimination of phosphate groups from glycolysis intermediates dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. MG is mostly detoxified by the combined actions of the enzymes glyoxalase I and glyoxalase II that together with glutathione make up the glyoxalase system. Under normal growth conditions, basal levels of MG remain low in plants; however, when plants are exposed to abiotic stress, MG can accumulate to much higher levels. Stress-induced MG functions as a toxic molecule, inhibiting different developmental processes, including seed germination, photosynthesis and root growth, whereas MG, at low levels, acts as an important signaling molecule, involved in regulating diverse events, such as cell proliferation and survival, control of the redox status of cells, and many other aspects of general metabolism and cellular homeostases. MG can modulate plant stress responses by regulating stomatal opening and closure, the production of reactive oxygen species, cytosolic calcium ion concentrations, the activation of inward rectifying potassium channels and the expression of many stress-responsive genes. MG appears to play important roles in signal transduction by transmitting and amplifying cellular signals and functions that promote adaptation of plants growing under adverse environmental conditions. Thus, MG is now considered as a potential biochemical marker for plant abiotic stress tolerance, and is receiving considerable attention by the scientific community. In this review, we will summarize recent findings regarding MG metabolism in plants under abiotic stress, and evaluate the concept of MG signaling. In addition, we will demonstrate the importance of giving consideration to MG metabolism and the glyoxalase system, when investigating plant adaptation and responses to various environmental stresses. PMID:27679640

  14. The Calcium Sensor CBL-CIPK Is Involved in Plant’s Response to Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    S. M. Nuruzzaman Manik

    2015-01-01

    Full Text Available Abiotic stress halts the physiological and developmental process of plant. During stress condition, CBL-CIPK complex is identified as a primary element of calcium sensor to perceive environmental signals. Recent studies established that this complex regulates downstream targets like ion channels and transporters in adverse stages conditions. Crosstalks between the CBL-CIPK complex and different abiotic stresses can extend our research area, which can improve and increase the production of genetically modified crops in response to abiotic stresses. How this complex links with environmental signals and creates adjustable circumstances under unfavorable conditions is now one of the burning issues. Diverse studies are already underway to delineate this signalling mechanism underlying different interactions. Therefore, up to date experimental results should be concisely published, thus paving the way for further research. The present review will concisely recapitulate the recent and ongoing research progress of positive ions (Mg2+, Na+, and K+, negative ions (NO3-, PO4-, and hormonal signalling, which are evolving from accumulating results of analyses of CBL and CIPK loss- or gain-of-function experiments in different species along with some progress and perspectives of our works. In a word, this review will give one step forward direction for more functional studies in this area.

  15. The 6-phosphogluconate Dehydrogenase Genes Are Responsive to Abiotic Stresses in Rice

    Institute of Scientific and Technical Information of China (English)

    Fu-Yun Hou; Ji Huang; Shan-Lin Yu; Hong-Sheng Zhang

    2007-01-01

    Glucose-6-phosphate dehydrogenase (G6PDH, E.C. 1.1.1.49) and 6-phosphogluconate dehydrogenase (6PGDH, EC 1.1.1.44) are both key enzymes of the pentose phosphate pathway (PPP). The OsG6PDH1 and Os6PGDH1 genes encoding cytosolic G6PDH and cytosolic 6PGDH were isoiated from rice (Oryza satlva L.). We have shown that Os6PGDH1 gene was up-regulated by salt stress. Here we reported the isolation and characterization of Os6PGDH2 from rice, which encode the plastidic counterpart of 6PGDH. Genomic organization analysis indicated that OsG6PDH1 and OsG6PDH2 genes contain multiple introns, whereas two Os6PGDH1 and Os6PGDH2 genes have no introns in their translated regions. In a step towards understanding the functions of the pentose phosphate pathway in plants in response to various abiotic stresses, the expressions of four genes in the rice seedlings treated by drought, cold, high salinity and abscisic acid (ABA) were investigated. The results show that OsG6PDH1 and OsG6PDH2 are not markedly regulated by the abiotic stresses detected. However, the transcript levels of both Os6PGDH1 and Os6PGDH2 are up-regulated in rice seedlings under drought, cold, high salinity and ABA treatments. Meanwhile,the enzyme activities of G6PDH and 6PGDH in the rice seedlings treated by various ablotlc stresses were investigated.Like the mRNA expression patterns, G6PDH activity remains constant but the 6PGDH increases steadily during the treatments. Taken together, we suggest that the pentose phosphate pathway may play an important role in rice responses to abiotlc stresses and the second key enzyme of PPP, 6PGDH, may function as a regulator controlling the efficiency of the pathway under abiotic stresses.

  16. Characterization and abiotic stress-responsive expression analysis of SGT1 genes in Brassica oleracea.

    Science.gov (United States)

    Shanmugam, Ashokraj; Thamilarasan, Senthil Kumar; Park, Jong-In; Jung, Mi Young; Nou, Ill-Sup

    2016-04-01

    SGT1 genes are involved in enhancing plant responses to various biotic and abiotic stresses. Brassica oleracea is known to contain two types of SGT1 genes, namely suppressor of G2 allele of SKP1 and suppressor of GCR2. In this study, through systematic analysis, four putative SGT1 genes were identified and characterized in B. oleracea. In phylogenetic analysis, the genes clearly formed separate groups, namely BolSGT1a, BolSGT1b (both suppressor of G2 allele of SKP1 types), and BolSGT1 (suppressor of GCR2). Functional domain analysis and organ-specific expression patterns suggested possible roles for BolSGT1 genes during stress conditions. BolSGT1 genes showed significant changes in expression in response to heat, cold, drought, salt, or ABA treatment. Interaction network analysis supported the expression analysis, and showed that the BolSGT1a and BolSGT1b genes are strongly associated with co-regulators during stress conditions. However, the BolSGT1 gene did not show any strong association. Hence, BolSGT1 might be a stress resistance-related gene that functions without a co-regulator. Our results show that BolSGT1 genes are potential target genes to improve B. oleracea resistance to abiotic stresses such as heat, cold, and salt. PMID:26966988

  17. 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.

  18. Calcium-Dependent Protein Kinase CPK21 Functions in Abiotic Stress Response in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Sandra Franz; Britta Ehlert; Anja Liese; Joachim Kurth; Anne-Claire Cazalé; Tina Romeis

    2011-01-01

    Calcium-dependent protein kinases(CDPKs)comprise a family of plant serine/threonine protein kinases in which the calcium sensing domain and the kinase effector domain are combined within one molecule.So far,a biological function in abiotic stress signaling has only been reported for few CDPK isoforms,whereas the underlying biochemical mechanism for these CDPKs is still mainly unknown.Here,we show that CPK21 from Arabidopsis thaliana is biochemically activated in vivo in response to hyperosmotic stress.Loss-of-function seedlings of cpk21 are more tolerant to hyperosmotic stress and mutant plants show increased stress responses with respect to marker gene expression and metabolite accumulation.In transgenic Arabidopsis complementation lines in the cpk21 mutant background,in which either CPK21 wildtype,or a full-length enzyme variant carrying an amino-acid substitution were stably expressed,stress responsitivity was restored by CPK21 but not with the kinase inactive variant.The biochemical characterization of in planta synthesized and purified CPK21 protein revealed that within the calcium-binding domain,N-terminal EF1- and EF2-motifs compared to C-terminal EF3- and EF4-motifs differ in their contribution to calcium-regulated kinase activity,suggesting a crucial role for the N-terminal EF-hand pair.Our data provide evidence for CPK21 contributing in abiotic stress signaling and suggest that the N-terminal EF-hand pair is a calcium-sensing determinant controlling specificity of CPK21 function.

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

    Science.gov (United States)

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

    2016-09-01

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

  20. Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and resistance mechanism.

    Science.gov (United States)

    Kissoudis, Christos; Sunarti, Sri; van de Wiel, Clemens; Visser, Richard G F; van der Linden, C Gerard; Bai, Yuling

    2016-09-01

    Stress conditions in agricultural ecosystems can occur at variable intensities. Different resistance mechanisms against abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effect of different levels of salt stress ranging from mild to severe (50, 100, and 150mM NaCl) on powdery mildew resistance and overall performance of tomato introgression lines with contrasting levels of partial resistance, as well as near-isogenic lines (NILs) carrying the resistance gene Ol-1 (associated with a slow hypersensitivity response; HR), ol-2 (an mlo mutant associated with papilla formation), and Ol-4 (an R gene associated with a fast HR). Powdery mildew resistance was affected by salt stress in a genotype- and stress intensity-dependent manner. In susceptible and partial resistant lines, increased susceptibility was observed under mild salt stress (50mM) which was accompanied by accelerated cell death-like senescence. In contrast, severe salt stress (150mM) reduced disease symptoms. Na(+) and Cl(-) accumulation in the leaves was linearly related to the decreased pathogen symptoms under severe stress. In contrast, complete resistance mediated by ol-2 and Ol-4 was unaffected under all treatment combinations, and was associated with a decreased growth penalty. Increased susceptibility and senescence under combined stress in NIL-Ol-1 was associated with the induction of ethylene and jasmonic acid pathway genes and the cell wall invertase gene LIN6. These results highlight the significance of stress severity and resistance type on the plant's performance under the combination of abiotic and biotic stress.

  1. Responses to combined abiotic and biotic stress in tomato are governed by stress intensity and resistance mechanism.

    Science.gov (United States)

    Kissoudis, Christos; Sunarti, Sri; van de Wiel, Clemens; Visser, Richard G F; van der Linden, C Gerard; Bai, Yuling

    2016-09-01

    Stress conditions in agricultural ecosystems can occur at variable intensities. Different resistance mechanisms against abiotic stress and pathogens are deployed by plants. Thus, it is important to examine plant responses to stress combinations under different scenarios. Here, we evaluated the effect of different levels of salt stress ranging from mild to severe (50, 100, and 150mM NaCl) on powdery mildew resistance and overall performance of tomato introgression lines with contrasting levels of partial resistance, as well as near-isogenic lines (NILs) carrying the resistance gene Ol-1 (associated with a slow hypersensitivity response; HR), ol-2 (an mlo mutant associated with papilla formation), and Ol-4 (an R gene associated with a fast HR). Powdery mildew resistance was affected by salt stress in a genotype- and stress intensity-dependent manner. In susceptible and partial resistant lines, increased susceptibility was observed under mild salt stress (50mM) which was accompanied by accelerated cell death-like senescence. In contrast, severe salt stress (150mM) reduced disease symptoms. Na(+) and Cl(-) accumulation in the leaves was linearly related to the decreased pathogen symptoms under severe stress. In contrast, complete resistance mediated by ol-2 and Ol-4 was unaffected under all treatment combinations, and was associated with a decreased growth penalty. Increased susceptibility and senescence under combined stress in NIL-Ol-1 was associated with the induction of ethylene and jasmonic acid pathway genes and the cell wall invertase gene LIN6. These results highlight the significance of stress severity and resistance type on the plant's performance under the combination of abiotic and biotic stress. PMID:27436279

  2. Functional ecological genomics to demonstrate general and specific responses to abiotic stress

    NARCIS (Netherlands)

    Roelofs, D.; Aarts, M.G.M.; Schat, H.; Straalen, van N.M.

    2008-01-01

    1. Stress is a major component of natural selection in soil ecosystems. The most prominent abiotic stress factors in the field are temperature extremes (heat, cold), dehydration (drought), high salinity and specific toxic compounds such as heavy metals. Organisms are able to deal with these stresses

  3. 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. PMID:27672389

  4. MATH-domain family shows response towards abiotic stress in Arabidopsis and rice

    Directory of Open Access Journals (Sweden)

    Hemant Ritturaj Kushwaha

    2016-06-01

    Full Text Available Response to stress represents a highly complex mechanism in plants involving a plethora of genes and gene families. It has been established that plants use some common set of genes and gene families for both biotic and abiotic stress responses leading to cross-talk phenomena. One such family, Meprin And TRAF Homology (MATH domain containing protein (MDCP, has been known to be involved in biotic stress response. In this study, we present genome-wide identification of various members of MDCP family from both Arabidopsis and rice. A large number of members identified in Arabidopsis and rice show the expansion and diversification of family in both the species. Localization of MDCP genes on the chromosomes of both Arabidopsis and rice show their presence in a few specific clusters on various chromosomes such as chromosome III in Arabidopsis and chromosome X in rice. For the functional analysis of MDCP genes, we used publicly available data for plant growth and development as well as biotic stresses and found differential expression of various members of the family. Further, we narrowed down 11 potential candidate genes in rice which showed high expression in various tissues and development stages as well biotic stress conditions. The expression analysis of these 11 genes in rice using qRT-PCR under drought and salinity stress identified OsM4 and OsMB11 to be highly expressed in both the stress conditions. Taken together, these data indicate that OsM4 and OsMB11 can be used as the potential candidates for generating stress resilient crops.

  5. 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.

  6. Coordinating metabolite changes with our perception of plant abiotic stress responses: emerging views revealed by integrative-omic analyses.

    Science.gov (United States)

    Radomiljac, Jordan D; Whelan, James; van der Merwe, Margaretha

    2013-09-06

    Metabolic configuration and adaptation under a range of abiotic stresses, including drought, heat, salinity, cold, and nutrient deprivation, are subjected to an intricate span of molecular pathways that work in parallel in order to enhance plant fitness and increase stress tolerance. In recent years, unprecedented advances have been made in identifying and linking different abiotic stresses, and the current challenge in plant molecular biology is deciphering how the signaling responses are integrated and transduced throughout metabolism. Metabolomics have often played a fundamental role in elucidating the distinct and overlapping biochemical changes that occur in plants. However, a far greater understanding and appreciation of the complexity in plant metabolism under specific stress conditions have become apparent when combining metabolomics with other-omic platforms. This review focuses on recent advances made in understanding the global changes occurring in plant metabolism under abiotic stress conditions using metabolite profiling as an integrated discovery platform.

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

    Directory of Open Access Journals (Sweden)

    Imen Klay

    2014-01-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

  9. Systematic Identification of Rice ABC1 Gene Family and Its Response to Abiotic Stress

    Institute of Scientific and Technical Information of China (English)

    GAO Qing-song; ZHANG Dan; Xu Liang; XU Chen-wu

    2011-01-01

    Members of the activity of bc1 complex (ABC1) family are protein kinases that are widely found in prokaryotes and eukaryotes.Previous studies showed that several plant ABC1 genes participated in the abiotic stress response.Here,we present the systematic identification of rice and Arabidopsis ABC1 genes and the expression analysis of rice ABC1 genes.A total of 15 and 17 ABC1 genes from the rice and Arabidopsis genomes,respectively,were identified using a bioinformatics approach.Phylogenetic analyses of these proteins suggested that the divergence of this family had occurred and their main characteristics were established before the monocot-dicot split.Indeed,species-specific expansion contributed to the evolution of this family in rice and Arabidopsis after the monocot-dicot split.Intron/exon structure analysis indicated that most of the orthologous genes had similar exon sizes,but diverse intron sizes,and the rice genes contained larger introns,moreover,intron gain was an important event accompanying the recent evolution of the rice ABC1 family.Multiple sequence alignment revealed one conserved amino acid segment and four conserved amino acids in the ABC1 domain.Online subcellular localization predicted that nine rice ABC1 proteins were localized in chloroplasts.Real-time RT-PCR established that the rice ABC1 genes were primarily expressed in leaves and the expression could be modulated by a broad range of abiotic factors such as H2O2,abscisic acid,low temperature,drought,darkness and high salinity.These results reveal that the rice ABC1 gene family plays roles in the environmental stress response and specific biological processes of rice.

  10. Global Expressions Landscape of NAC Transcription Factor Family and Their Responses to Abiotic Stresses in Citrullus lanatus

    Science.gov (United States)

    Lv, Xiaolong; Lan, Shanrong; Guy, Kateta Malangisha; Yang, Jinghua; Zhang, Mingfang; Hu, Zhongyuan

    2016-01-01

    Watermelon (Citrullus lanatus) is one xerophyte that has relative higher tolerance to drought and salt stresses as well as more sensitivity to cold stress, compared with most model plants. These characteristics facilitate it a potential model crop for researches on salt, drought or cold tolerance. In this study, a genome-wide comprehensive analysis of the ClNAC transcription factor (TF) family was carried out for the first time, to investigate their transcriptional profiles and potential functions in response to these abiotic stresses. The expression profiling analysis reveals that several NAC TFs are highly responsive to abiotic stresses and development, for instance, subfamily IV NACs may play roles in maintaining water status under drought or salt conditions, as well as water and metabolites conduction and translocation toward fruit. In contrast, rapid and negative responses of most of the ClNACs to low-temperature adversity may be related to the sensitivity to cold stress. Crosstalks among these abiotic stresses and hormone (abscisic acid and jasmonic acid) pathways were also discussed based on the expression of ClNAC genes. Our results will provide useful insights for the functional mining of NAC family in watermelon, as well as into the mechanisms underlying abiotic tolerance in other cash crops. PMID:27491393

  11. Importance of abiotic stress as a range-limit determinant for European plants: insights from species responses to climatic gradients

    DEFF Research Database (Denmark)

    Normand, Signe; Treier, Urs; Randin, Christophe;

    2009-01-01

    Aim We examined whether species occurrences are primarily limited by physiological tolerance in the abiotically more stressful end of climatic gradients (the asymmetric abiotic stress limitation (AASL) hypothesis) and the geographical predictions of this hypothesis: abiotic stress mainly determin...... upper-latitudinal and upper-altitudinal species range limits, and the importance of abiotic stress for these range limits increases the further northwards and upwards a species occurs...

  12. 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 obse

  13. QlicRice: a web interface for abiotic stress responsive QTL and loci interaction channels in rice.

    Science.gov (United States)

    Smita, Shuchi; Lenka, Sangram Keshari; Katiyar, Amit; Jaiswal, Pankaj; Preece, Justin; Bansal, Kailash Chander

    2011-01-01

    The QlicRice database is designed to host publicly accessible, abiotic stress responsive quantitative trait loci (QTLs) in rice (Oryza sativa) and their corresponding sequenced gene loci. It provides a platform for the data mining of abiotic stress responsive QTLs, as well as browsing and annotating associated traits, their location on a sequenced genome, mapped expressed sequence tags (ESTs) and tissue and growth stage-specific expressions on the whole genome. Information on QTLs related to abiotic stresses and their corresponding loci from a genomic perspective has not yet been integrated on an accessible, user-friendly platform. QlicRice offers client-responsive architecture to retrieve meaningful biological information--integrated and named 'Qlic Search'--embedded in a query phrase autocomplete feature, coupled with multiple search options that include trait names, genes and QTL IDs. A comprehensive physical and genetic map and vital statistics have been provided in a graphical manner for deciphering the position of QTLs on different chromosomes. A convenient and intuitive user interface have been designed to help users retrieve associations to agronomically important QTLs on abiotic stress response in rice. Database URL: http://nabg.iasri.res.in:8080/qlic-rice/. PMID:21965557

  14. Calcium sensors as key hubs in plant responses to biotic and abiotic stresses

    Directory of Open Access Journals (Sweden)

    Benoît eRanty

    2016-03-01

    Full Text Available The Ca2+ ion is recognized as a crucial second messenger in signalling pathways coupling the perception of environmental stimuli to plant adaptive responses. Indeed, one of the earliest events following the perception of environmental changes (temperature, salt stress, drought, pathogen or herbivore attack is intracellular variation of free calcium concentrations. These calcium variations differ in their spatio-temporal characteristics (subcellular location, amplitude, kinetics with the nature and strength of the stimulus and, for this reason, they are considered as signatures encrypting information from the initial stimulus. This information is believed to drive a specific response by decoding via calcium-binding proteins.Based on recent examples, we illustrate how individual calcium sensors from the calcium-dependent protein kinase (CPK and calmodulin-like protein (CML families can integrate inputs from various environmental changes. Focusing on members of these two families, shown to be involved in plant responses to both abiotic and biotic stimuli, we discuss their role as key hubs and we put forward hypotheses explaining how they can drive the signalling pathways towards the appropriate plant responses.

  15. Analysis of global gene expression in Brachypodium distachyon reveals extensive network plasticity in response to abiotic stress.

    Directory of Open Access Journals (Sweden)

    Henry D Priest

    Full Text Available Brachypodium distachyon is a close relative of many important cereal crops. Abiotic stress tolerance has a significant impact on productivity of agriculturally important food and feedstock crops. Analysis of the transcriptome of Brachypodium after chilling, high-salinity, drought, and heat stresses revealed diverse differential expression of many transcripts. Weighted Gene Co-Expression Network Analysis revealed 22 distinct gene modules with specific profiles of expression under each stress. Promoter analysis implicated short DNA sequences directly upstream of module members in the regulation of 21 of 22 modules. Functional analysis of module members revealed enrichment in functional terms for 10 of 22 network modules. Analysis of condition-specific correlations between differentially expressed gene pairs revealed extensive plasticity in the expression relationships of gene pairs. Photosynthesis, cell cycle, and cell wall expression modules were down-regulated by all abiotic stresses. Modules which were up-regulated by each abiotic stress fell into diverse and unique gene ontology GO categories. This study provides genomics resources and improves our understanding of abiotic stress responses of Brachypodium.

  16. Involvement of Calmodulin and Calmodulin-like Proteins in Plant Responses to Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    B W Poovaiah

    2015-08-01

    Full Text Available Transient changes in intracellular Ca2+ concentration have been well recognized to act as cell signals coupling various environmental stimuli to appropriate physiological responses with accuracy and specificity in plants. Calmodulin (CaM and calmodulin-like proteins (CMLs are major Ca2+ sensors, playing critical roles in interpreting encrypted Ca2+ signals. Ca2+-loaded CaM/CMLs interact and regulate a broad spectrum of target proteins such as channels/pumps/antiporters for various ions, transcription factors, protein kinases, protein phosphatases, metabolic enzymes and proteins with unknown biochemical functions. Many of the target proteins of CaM/CMLs directly or indirectly regulate plant responses to environmental stresses. Basic information about stimulus-induced Ca2+ signal and overview of Ca2+ signal perception and transduction are briefly discussed in the beginning of this review. How CaM/CMLs are involved in regulating plant responses to abiotic stresses are emphasized in this review. Exciting progress has been made in the past several years, such as the elucidation of Ca2+/CaM-mediated regulation of AtSR1/CAMTA3 and plant responses to chilling and freezing stresses, Ca2+/CaM-mediated regulation of CAT3, MAPK8 and MKP1 in homeostasis control of ROS signals, discovery of CaM7 as a DNA-binding transcription factor regulating plant response to light signals. However, many key questions in Ca2+/CaM-mediated signaling warrant further investigation. Ca2+/CaM-mediated regulation of most of the known target proteins is presumed based on their interaction. The downstream targets of CMLs are mostly unknown, and how specificity of Ca2+ signaling could be realized through the actions of CaM/CMLs and their target proteins is largely unknown. Future breakthroughs in Ca2+/CaM-mediated signaling will not only improve our understanding of how plants respond to environmental stresses, but also provide the knowledge base to improve stress-tolerance of crops.

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

    Directory of Open Access Journals (Sweden)

    Pushpika eUdawat

    2016-04-01

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

  18. G-protein signalling components GCR1 and GPA1 mediate responses to multiple abiotic stresses in Arabidopsis

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    Navjyoti eChakraborty

    2015-11-01

    Full Text Available G-protein signalling components have been implicated in some individual stress responses in Arabidopsis, but have not been comprehensively evaluated at the genetic and biochemical level. Stress emerged as the largest functional category in our whole transcriptome analyses of knock-out mutants of GCR1 and/or GPA1 in Arabidopsis (Chakraborty et al., 2015a, PloS one 10, e0117819 and Chakraborty et al., 2015b, Plant Mol. Biol., doi: 10.1007/s11103-015-0374-2. This led us to ask whether G-protein signalling components offer converging points in the plant’s response to multiple abiotic stresses. In order to test this hypothesis, we carried out detailed analysis of the stress category in the present study, which revealed 144 differentially expressed genes (DEGs, spanning a wide range of abiotic stresses, including heat, cold, salt, light stress etc. Only 10 of these DEGs are shared by all the three mutants, while the single mutants (GCR1/GPA1 shared more DEGs between themselves than with the double mutant (GCR1-GPA1. RT-qPCR validation of 28 of these genes spanning different stresses revealed identical regulation of the DEGs shared between the mutants. We also validated the effects of cold, heat and salt stresses in all the 3 mutants and WT on % germination, root and shoot length, relative water content, proline content, lipid peroxidation and activities of catalase, ascorbate peroxidase and superoxide dismutase. All the 3 mutants showed evidence of stress tolerance, especially to cold, followed by heat and salt, in terms of all the above parameters. This clearly shows the role of GCR1 and GPA1 in mediating the plant’s response to multiple abiotic stresses for the first time, especially cold, heat and salt stresses. This also implies a role for classical G-protein signalling pathways in stress sensitivity in the normal plants of Arabidopsis. This is also the first genetic and biochemical evidence of abiotic stress tolerance rendered by knock

  19. Identification of Synchronized Role of Transcription Factors, Genes, and Enzymes in Arabidopsis thaliana under Four Abiotic Stress Responsive Pathways

    Directory of Open Access Journals (Sweden)

    Samsad Razzaque

    2014-01-01

    Full Text Available Microarray datasets are widely used resources to predict and characterize functional entities of the whole genomics. The study initiated here aims to identify overexpressed stress responsive genes using microarray datasets applying in silico approaches. The target also extended to build a protein-protein interaction model of regulatory genes with their upstream and downstream connection in Arabidopsis thaliana. Four microarray datasets generated treating abiotic stresses like salinity, cold, drought, and abscisic acid (ABA were chosen. Retrieved datasets were firstly filtered based on their expression comparing to control. Filtered datasets were then used to create an expression hub. Extensive literature mining helped to identify the regulatory molecules from the expression hub. The study brought out 42 genes/TF/enzymes as the role player during abiotic stress response. Further bioinformatics study and also literature mining revealed that thirty genes from those forty-two were highly correlated in all four datasets and only eight from those thirty genes were determined as highly responsive to the above abiotic stresses. Later their protein-protein interaction (PPI, conserved sequences, protein domains, and GO biasness were studied. Some web based tools and software like String database, Gene Ontology, InterProScan, NCBI BLASTn suite, etc. helped to extend the study arena.

  20. 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.

  1. Rice Mitogen-activated Protein Kinase Gene Family and Its Role in Biotic and Abiotic Stress Response

    Institute of Scientific and Technical Information of China (English)

    Jai S. Rohila; Yinong Yang

    2007-01-01

    The mitogen-activated protein kinase (MARK) cascade is an important signaling module that transduces extracellular stimuli into intracellular responses in eukaryotic organisms. An increasing body of evidence has shown that the MAPK-mediated cellular signaling is crucial to plant growth and development, as well as biotic and abiotic stress responses. To date, a total of 17 MARK genes have been identified from the rice genome. Expression profiling, biochemical characterization and/or functional analysis were carried out with many members of the rice MARK gene family, especially those associated with biotic and abiotic stress responses. In this review, the phylogenetic relationship and classification of rice MARK genes are discussed to facilitate a simple nomenclature and standard annotation of the rice MARK gene family. Functional data relating to biotic and abiotic stress responses are reviewed for each MARK group and show that despite overlapping in functionality, there is a certain level of functional specificity among different rice MAP kinases. The future challenges are to functionally characterize each MARK, to identify their downstream substrates and upstream kinases, and to genetically manipulate the MARK signaling pathway in rice crops for the improvement of agronomically important traits.

  2. Microarray meta-analysis focused on the response of genes involved in redox homeostasis to diverse abiotic stresses in rice

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    Joao eBraga De Abreu Neto

    2016-01-01

    Full Text Available Plants are exposed to a wide range of abiotic stresses, which often occur in combination. Because physiological investigations typically focus on one stress, our understanding of unspecific stress responses remains limited. The plant redox homeostasis, i.e. the production and removal of reactive oxygen species (ROS, may be involved in many environmental stress conditions. Therefore, this study intended to identify genes, which are activated in diverse abiotic stresses, focusing on ROS–related pathways. We conducted a meta-analysis (MA of microarray experiments, focusing on rice. Transcriptome data were mined from public databases and fellow researchers, which represented 36 different experiments and investigated diverse abiotic stresses, including ozone stress, drought, heat, cold, salinity, and mineral deficiencies/toxicities. To overcome the inherent artefacts of different MA methods, data were processed using Fisher, rOP, REM and product of rank (GeneSelector, and genes identified by most approaches were considered as shared differentially expressed genes (DEGs. Two MA strategies were adopted: first, datasets were separated into shoot, root and seedling experiments, and these tissues were analyzed separately to identify shared DEGs. Second, shoot and seedling experiments were classed into oxidative stress (OS, i.e. ozone and hydrogen peroxide treatments directly producing ROS in plant tissue, and other abiotic stresses (AS, in which ROS production is indirect. In all tissues and stress conditions, genes a priori considered as ROS-related were overrepresented among the DEGs, as they represented 4% of all expressed genes but 7-10% of the DEGs. The combined MA approach was substantially more conservative than individual MA methods and identified 1001 shared DEGs in shoots, 837 shared DEGs in root, and 1172 shared DEGs in seedlings. Within the OS and AS groups, 990 and 1727 shared DEGs were identified, respectively. In total, 311 genes were

  3. 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.

  4. Involvement of rice histone deacetylase HDA705 in seed germination and in response to ABA and abiotic stresses.

    Science.gov (United States)

    Zhao, Jinhui; Li, Mingzhi; Gu, Dachuan; Liu, Xuncheng; Zhang, Jianxia; Wu, Kunlin; Zhang, Xinhua; Teixeira da Silva, Jaime A; Duan, Jun

    2016-02-01

    Histone acetylation and deacetylation play crucial roles in the modification of chromatin structure and regulation of gene expression in eukaryotes. Histone acetyltransferases (HATs) and histone deacetylases (HDACs) assist to maintain the balance of chromatin acetylation status. Previous studies showed that plant HDACs are key regulators involved in response to development and stresses. In this study, we examined the expression pattern and function of HDA705, a member of the RPD3/HDA1-type HDAC in rice. Overexpression of HDA705 in rice decreased ABA and salt stress resistance during seed germination. Delayed seed germination of HDA705 overexpression lines was associated with down-regulated expression of GA biosynthetic genes and up-regulation of ABA biosynthetic genes. Moreover, overexpression of HDA705 in rice enhanced osmotic stress resistance during the seedling stage. Our findings demonstrate that HDA705 may play a role in regulating seed germination and the response to abiotic stresses in rice. PMID:26772883

  5. Differential expression of seven conserved microRNAs in response to abiotic stress and their regulatory network in Helianthus annuus.

    Science.gov (United States)

    Ebrahimi Khaksefidi, Reyhaneh; Mirlohi, Shirin; Khalaji, Fahimeh; Fakhari, Zahra; Shiran, Behrouz; Fallahi, Hossein; Rafiei, Fariba; Budak, Hikmet; Ebrahimie, Esmaeil

    2015-01-01

    Biotic and abiotic stresses affect plant development and production through alternation of the gene expression pattern. Gene expression itself is under the control of different regulators such as miRNAs and transcription factors (TFs). MiRNAs are known to play important roles in regulation of stress responses via interacting with their target mRNAs. Here, for the first time, seven conserved miRNAs, associated with drought, heat, salt and cadmium stresses were characterized in sunflower. The expression profiles of miRNAs and their targets were comparatively analyzed between leaves and roots of plants grown under the mentioned stress conditions. Gene ontology analysis of target genes revealed that they are involved in several important pathways such as auxin and ethylene signaling, RNA mediated silencing and DNA methylation processes. Gene regulatory network highlighted the existence of cross-talks between these stress-responsive miRNAs and the other stress responsive genes in sunflower. Based on network analysis, we suggest that some of these miRNAs in sunflower such as miR172 and miR403 may play critical roles in epigenetic responses to stress. It seems that depending on the stress type, theses miRNAs target several pathways and cellular processes to help sunflower to cope with drought, heat, salt and cadmium stress conditions in a tissue-associated manner. PMID:26442054

  6. Expression Profiling of Abiotic Stress-Inducible Genes in response to Multiple Stresses in Rice (Oryza sativa L. Varieties with Contrasting Level of Stress Tolerance

    Directory of Open Access Journals (Sweden)

    Supratim Basu

    2014-01-01

    Full Text Available The present study considered transcriptional profiles and protein expression analyses from shoot and/or root tissues under three abiotic stress conditions, namely, salinity, dehydration, and cold, as well as following exogenous abscisic acid treatment, at different time points of stress exposure in three indica rice varieties, IR-29 (salt sensitive, Pokkali, and Nonabokra (both salt tolerant. The candidate genes chosen for expression studies were HKT-1, SOS-3, NHX-1, SAPK5, SAPK7, NAC-1, Rab16A, OSBZ8, DREBP2, CRT/DREBP, WRKY24, and WRKY71, along with the candidate proteins OSBZ8, SAMDC, and GST. Gene expression profile revealed considerable differences between the salt-sensitive and salt-tolerant rice varieties, as the expression in the latter was higher even at the constitutive level, whereas it was inducible only by corresponding stress signals in IR-29. Whether in roots or shoots, the transcriptional responses to different stressors peaked following 24 h of stress/ABA exposure, and the transcript levels enhanced gradually with the period of exposure. The generality of stress responses at the transcriptional level was therefore time dependent. Heat map data also showed differential transcript abundance in the three varieties, correlating the observation with transcript profiling. In silico analysis of the upstream regions of all the genes represented the existence of conserved sequence motifs in single or multiple copies that are indispensable to abiotic stress response. Overall, the transcriptome and proteome analysis undertaken in the present study indicated that genes/proteins conferring tolerance, belonging to different functional classes, were overrepresented, thus providing novel insight into the functional basis of multiple stress tolerance in indica rice varieties. The present work will pave the way in future to select gene(s for overexpression, so as to generate broad spectrum resistance to multiple stresses simultaneously.

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

    KAUST Repository

    Zhang, Xiujuan

    2013-06-01

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

  8. X1-homologous genes family as central components in biotic and abiotic stresses response in maize (Zea mays L.).

    Science.gov (United States)

    Zhang, Zhongbao; Chen, Yajuan; Zhao, Dan; Li, Ruifen; Wang, Hongzhi; Zhang, Jiewei; Wei, Jianhua

    2014-03-01

    X1-homologous genes (XHS) encode plant specific proteins containing three basic domains (XH, XS, zf-XS). In spite of their physiological importance, systematic analyses of ZmXHS genes have not yet been explored. In this study, we isolated and characterized ten ZmXHS genes in a whole-of-genome analysis of the maize genome. A total of ten members of this family were identified in maize genome. The ten ZmXHS genes were distributed on seven maize chromosomes. Multiple alignment and motif display results revealed that most ZmXHS proteins share all the three conserved domains. Putative cis-elements involved in abiotic stress responsive, phytohormone, pollen-specific and quantitative, seed development and germination, light and circadian rhythms regulation, Ca(2+)-responsive, root hair cell-specific, and CO(2)-responsive transcriptional activation were observed in the promoters of ZmXHS genes. Yeast hybrid assay revealed that the XH domain of ZmXHS5 was necessary for interaction with itself and ZmXHS2. Microarray data showed that the ZmXHS genes had tissue-specific expression patterns in the maize developmental steps and biotic stresses response. Quantitative real-time PCR analysis results indicated that, except ZmXHS9, the other nine ZmXHS genes were induced in the seedling leaves by at least one of the four abiotic stresses applied. PMID:24676795

  9. 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.

  10. Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses

    Directory of Open Access Journals (Sweden)

    Su Zhen

    2011-07-01

    Full Text Available Abstract Background Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation. Results A microarray experiment was conducted using root samples collected 6, 24, and 48 h after application of 180 mM NaCl. Analysis of 11 statistically significant expression profiles revealed different behaviors between primary and secondary metabolism pathways in response to external stress. Secondary metabolism that helps to maintain osmotic balance was induced. One of the highly induced transcription factor genes was successfully cloned, and was named MtCBF4. Phylogenetic analysis revealed that MtCBF4, which belongs to the AP2-EREBP transcription factor family, is a novel member of the CBF transcription factor in M. truncatula. MtCBF4 is shown to be a nuclear-localized protein. Expression of MtCBF4 in M. truncatula was induced by most of the abiotic stresses, including salt, drought, cold, and abscisic acid, suggesting crosstalk between these abiotic stresses. Transgenic Arabidopsis over-expressing MtCBF4 enhanced tolerance to drought and salt stress, and activated expression of downstream genes that contain DRE elements. Over-expression of MtCBF4 in M. truncatula also enhanced salt tolerance and induced expression level of corresponding downstream genes. Conclusion Comprehensive transcriptomic analysis revealed complex mechanisms exist in plants in response to salt stress. The novel transcription factor gene MtCBF4 identified here played an important role in response to abiotic stresses, indicating that it might be a good candidate gene for genetic improvement to produce stress-tolerant plants.

  11. Circadian regulation of abiotic stress tolerance in plants.

    Science.gov (United States)

    Grundy, Jack; Stoker, Claire; Carré, Isabelle A

    2015-01-01

    Extremes of temperatures, drought and salinity cause widespread crop losses throughout the world and impose severe limitations on the amount of land that can be used for agricultural purposes. Hence, there is an urgent need to develop crops that perform better under such abiotic stress conditions. Here, we discuss intriguing, recent evidence that circadian clock contributes to plants' ability to tolerate different types of environmental stress, and to acclimate to them. The clock controls expression of a large fraction of abiotic stress-responsive genes, as well as biosynthesis and signaling downstream of stress response hormones. Conversely, abiotic stress results in altered expression and differential splicing of the clock genes, leading to altered oscillations of downstream stress-response pathways. We propose a range of mechanisms by which this intimate coupling between the circadian clock and environmental stress-response pathways may contribute to plant growth and survival under abiotic stress.

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

    Institute of Scientific and Technical Information of China (English)

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

    2015-01-01

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

  13. Expression Analysis of MYC Genes from Tamarix hispida in Response to Different Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    Guifeng Liu

    2012-01-01

    Full Text Available The MYC genes are a group of transcription factors containing both bHLH and ZIP motifs that play important roles in the regulation of abscisic acid (ABA-responsive genes. In the present study, to investigate the roles of MYC genes under NaCl, osmotic and ABA stress conditions, nine MYC genes were cloned from Tamarix hispida. Real-time reverse-transcriptase (RT-PCR showed that all nine MYC genes were expressed in root, stem and leaf tissues, but that the levels of the transcripts of these genes in the various tissues differed notably. The MYC genes were highly induced in the roots in response to ABA, NaCl and osmotic stresses after 3 h; however, in the stem and leaf tissues, MYC genes were highly induced only when exposed to these stresses for 6 h. In addition, most of these MYC genes were highly expressed in roots in comparison with stems and leaves. Furthermore, the MYC genes were more highly induced in roots than in stem and leaf tissues, indicating that these genes may play roles in stress responses mainly in the roots rather than the stems and leaves. The results of this present study suggest that MYCs are involved in salt and osmotic stress tolerances and are controlled by the ABA signal transduction pathway.

  14. Genome-wide SNP discovery and linkage analysis in barley based on genes responsive to abiotic stress.

    Science.gov (United States)

    Rostoks, Nils; Mudie, Sharon; Cardle, Linda; Russell, Joanne; Ramsay, Luke; Booth, Allan; Svensson, Jan T; Wanamaker, Steve I; Walia, Harkamal; Rodriguez, Edmundo M; Hedley, Peter E; Liu, Hui; Morris, Jenny; Close, Timothy J; Marshall, David F; Waugh, Robbie

    2005-12-01

    More than 2,000 genome-wide barley single nucleotide polymorphisms (SNPs) were developed by resequencing unigene fragments from eight diverse accessions. The average genome-wide SNP frequency observed in 877 unigenes was 1 SNP per 200 bp. However, SNP frequency was highly variable with the least number of SNP and SNP haplotypes observed within European cultivated germplasm reflecting effects of breeding history on genetic diversity. More than 300 SNP loci were mapped genetically in three experimental mapping populations which allowed the construction of an integrated SNP map incorporating a large number of RFLP, AFLP and SSR markers (1,237 loci in total). The genes used for SNP discovery were selected based on their transcriptional response to a variety of abiotic stresses. A set of known barley abiotic stress QTL was positioned on the linkage map, while the available sequence and gene expression information facilitated the identification of genes potentially associated with these traits. Comparison of the sequenced SNP loci to the rice genome sequence identified several regions of highly conserved gene order providing a framework for marker saturation in barley genomic regions of interest. The integration of genome-wide SNP and expression data with available genetic and phenotypic information will facilitate the identification of gene function in barley and other non-model organisms. PMID:16244872

  15. Basic Techniques to Assess Seed Germination Responses to Abiotic Stress in Arabidopsis thaliana.

    Science.gov (United States)

    Piskurewicz, Urszula; Lopez-Molina, Luis

    2016-01-01

    The model organism Arabidopsis thaliana has been extensively used to unmask the molecular genetic signaling pathways controlling seed germination in plants. In Arabidopsis, the normal seed to seedling developmental transition involves testa rupture soon followed by endosperm rupture, radicle elongation, root hair formation, cotyledon expansion, and greening. Here we detail a number of basic procedures to assess Arabidopsis seed germination in response to different light (red and far-red pulses), temperature (seed thermoinhibition), and water potential (osmotic stress) environmental conditions. We also discuss the role of the endosperm and how its germination-repressive activity can be monitored genetically by means of a seed coat bedding assay. Finally we detail how to evaluate germination responses to changes in gibberellin (GA) and abscisic acid (ABA) levels by manipulating pharmacologically the germination medium. PMID:26867624

  16. Photosynthetic response to fluctuating environments and photoprotective strategies under abiotic stress.

    Science.gov (United States)

    Yamori, Wataru

    2016-05-01

    Plants in natural environments must cope with diverse, highly dynamic, and unpredictable conditions. They have mechanisms to enhance the capture of light energy when light intensity is low, but they can also slow down photosynthetic electron transport to prevent the production of reactive oxygen species and consequent damage to the photosynthetic machinery under excess light. Plants need a highly responsive regulatory system to balance the photosynthetic light reactions with downstream metabolism. Various mechanisms of regulation of photosynthetic electron transport under stress have been proposed, however the data have been obtained mainly under environmentally stable and controlled conditions. Thus, our understanding of dynamic modulation of photosynthesis under dramatically fluctuating natural environments remains limited. In this review, first I describe the magnitude of environmental fluctuations under natural conditions. Next, I examine the effects of fluctuations in light intensity, CO2 concentration, leaf temperature, and relative humidity on dynamic photosynthesis. Finally, I summarize photoprotective strategies that allow plants to maintain the photosynthesis under stressful fluctuating environments. The present work clearly showed that fluctuation in various environmental factors resulted in reductions in photosynthetic rate in a stepwise manner at every environmental fluctuation, leading to the conclusion that fluctuating environments would have a large impact on photosynthesis. PMID:27023791

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

    OpenAIRE

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

    2014-01-01

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

  18. Isolation of a novel peroxisomal catalase gene from sugarcane, which is responsive to biotic and abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Yachun Su

    Full Text Available Catalase is an iron porphyrin enzyme, which serves as an efficient scavenger of reactive oxygen species (ROS to avoid oxidative damage. In sugarcane, the enzymatic activity of catalase in a variety (Yacheng05-179 resistant to the smut pathogen Sporisorium scitamineum was always higher than that of the susceptible variety (Liucheng03-182, suggesting that catalase activity may have a positive correlation with smut resistance in sugarcane. To understand the function of catalase at the molecular level, a cDNA sequence of ScCAT1 (GenBank Accession No. KF664183, was isolated from sugarcane infected by S. scitamineum. ScCAT1 was predicted to encode 492 amino acid residues, and its deduced amino acid sequence shared a high degree of homology with other plant catalases. Enhanced growth of ScCAT1 in recombinant Escherichia coli Rosetta cells under the stresses of CuCl2, CdCl2 and NaCl indicated its high tolerance. Q-PCR results showed that ScCAT1 was expressed at relatively high levels in the bud, whereas expression was moderate in stem epidermis and stem pith. Different kinds of stresses, including S. scitamineum challenge, plant hormones (SA, MeJA and ABA treatments, oxidative (H2O2 stress, heavy metal (CuCl2 and hyper-osmotic (PEG and NaCl stresses, triggered a significant induction of ScCAT1. The ScCAT1 protein appeared to localize in plasma membrane and cytoplasm. Furthermore, histochemical assays using DAB and trypan blue staining, as well as conductivity measurement, indicated that ScCAT1 may confer the sugarcane immunity. In conclusion, the positive response of ScCAT1 to biotic and abiotic stresses suggests that ScCAT1 is involved in protection of sugarcane against reactive oxidant-related environmental stimuli.

  19. Overexpression of calmodulin-like (ShCML44) stress-responsive gene from Solanum habrochaites enhances tolerance to multiple abiotic stresses.

    Science.gov (United States)

    Munir, Shoaib; Liu, Hui; Xing, Yali; Hussain, Saddam; Ouyang, Bo; Zhang, Yuyang; Li, Hanxia; Ye, Zhibiao

    2016-01-01

    Calmodulin-like (CML) proteins are important Ca(2+) sensors, which play significant role in mediating plant stress tolerance. In the present study, cold responsive calmodulin-like (ShCML44) gene was isolated from cold tolerant wild tomato (Solanum habrochaites), and functionally characterized. The ShCML44 was differentially expressed in all plant tissues including root, stem, leaf, flower and fruit, and was strongly up-regulated under cold, drought and salinity stresses along with plant growth hormones. Under cold stress, progressive increase in the expression of ShCML44 was observed particularly in cold-tolerant S. habrochaites. The ShCML44-overexpressed plants showed greater tolerance to cold, drought, and salinity stresses, and recorded higher germination and better seedling growth. Transgenic tomato plants demonstrated higher antioxidant enzymes activity, gas exchange and water retention capacity with lower malondialdehyde accumulation and membrane damage under cold and drought stresses compared to wild-type. Moreover, transgenic plants exhibited reduced reactive oxygen species and higher relative water contents under cold and drought stress, respectively. Greater stress tolerance of transgenic plants was further reflected by the up-/down-regulation of stress-related genes including SOD, GST, CAT, POD, LOX, PR and ERD. In crux, these results strengthen the molecular understanding of ShCML44 gene to improve the abiotic stress tolerance in tomato. PMID:27546315

  20. Overexpression of the NDR1/HIN1-Like Gene NHL6 Modifies Seed Germination in Response to Abscisic Acid and Abiotic Stresses in Arabidopsis.

    Science.gov (United States)

    Bao, Yan; Song, Wei-Meng; Pan, Jing; Jiang, Chun-Mei; Srivastava, Renu; Li, Bei; Zhu, Lu-Ying; Su, Hong-Yan; Gao, Xiao-Shu; Liu, Hua; Yu, Xiang; Yang, Lei; Cheng, Xian-Hao; Zhang, Hong-Xia

    2016-01-01

    NHL (NDR1/HIN1-like) genes play crucial roles in pathogen induced plant responses to biotic stress. Here, we report the possible function of NHL6 in plant response to abscisic acid (ABA) and abiotic stress. NHL6 was highly expressed in non-germinated seeds, and its expression was strongly induced by ABA and multiple abiotic stress signals. Loss-of-function of NHL6 decreased sensitivity to ABA in the early developmental stages including seed germination and post-germination seedling growth of the nhl6 mutants. However, overexpression of NHL6 increased sensitivity to ABA, salt and osmotic stress of the transgenic plants. Further studies indicated that the increased sensitivity in the 35S::NHL6 overexpressing plants could be a result of both ABA hypersensitivity and increased endogenous ABA accumulation under the stress conditions. It was also seen that the ABA-responsive element binding factors AREB1, AREB2 and ABF3 could regulate NHL6 expression at transcriptional level. Our results indicate that NHL6 plays an important role in the abiotic stresses-induced ABA signaling and biosynthesis, particularly during seed germination and early seedling development in Arabidopsis.

  1. When bad guys become good ones: the key role of reactive oxygen species and nitric oxide in the plant responses to abiotic stress

    Directory of Open Access Journals (Sweden)

    Fernanda Dos Santos Farnese

    2016-04-01

    Full Text Available The natural environment of plants is composed of a complex set of abiotic stresses and their ability to respond to these stresses is highly flexible and finely balanced through the interaction between signaling molecules. In this review, we highlight the integrated action between reactive oxygen species (ROS and reactive nitrogen species (RNS, particularly nitric oxide (NO, involved in the acclimation to different abiotic stresses. Under stressful conditions, the biosynthesis transport and the metabolism of ROS and NO influence plant response mechanisms. The enzymes involved in ROS and NO synthesis and scavenging can be found in different cells compartments and their temporal and spatial locations are determinant for signaling mechanisms. Both ROS and NO are involved in long distances signaling (ROS wave and GSNO transport, promoting an acquired systemic acclimation to abiotic stresses. The mechanisms of abiotic stresses response triggered by ROS and NO involve some general steps, as the enhancement of antioxidant systems, but also stress-specific mechanisms, according to the stress type (drought, hypoxia, heavy metals, etc, and demand the interaction with other signaling molecules, such as MAPK, plant hormones and calcium. The transduction of ROS and NO bioactivity involves post-translational modifications of proteins, particularly S-glutathionylation for ROS, and S-nitrosylation for NO. These changes may alter the activity, stability, and interaction with other molecules or subcellular location of proteins, changing the entire cell dynamics and contributing to the maintenance of homeostasis. However, despite the recent advances about the roles of ROS and NO in signaling cascades, many challenges remain, and future studies focusing on the signaling of these molecules in planta are still necessary.

  2. Molecular approaches to improve rice abiotic stress tolerance.

    Science.gov (United States)

    Mizoi, Junya; Yamaguchi-Shinozaki, Kazuko

    2013-01-01

    Abiotic stress is a major factor limiting productivity of rice crops in large areas of the world. Because plants cannot avoid abiotic stress by moving, they have acquired various mechanisms for stress tolerance in the course of their evolution. Enhancing or introducing such mechanisms in rice is one effective way to develop stress-tolerant cultivars. Based on physiological studies on stress responses, recent progress in plant molecular biology has enabled discovery of many genes involved in stress tolerance. These genes include regulatory genes, which regulate stress response (e.g., transcription factors and protein kinases), and functional genes, which protect the cell (e.g., enzymes for generating protective metabolites and proteins). Both kinds of genes are used to increase stress tolerance in rice. In addition, several quantitative trait loci (QTLs) associated with higher stress tolerance have been cloned, contributing to the discovery of significantly important genes for stress tolerance.

  3. Responses of transgenic Arabidopsis plants and recombinant yeast cells expressing a novel durum wheat manganese superoxide dismutase TdMnSOD to various abiotic stresses.

    Science.gov (United States)

    Kaouthar, Feki; Ameny, Farhat-Khemakhem; Yosra, Kamoun; Walid, Saibi; Ali, Gargouri; Faiçal, Brini

    2016-07-01

    In plant cells, the manganese superoxide dismutase (Mn-SOD) plays an elusive role in the response to oxidative stress. In this study, we describe the isolation and functional characterization of a novel Mn-SOD from durum wheat (Triticum turgidum L. subsp. Durum), named TdMnSOD. Molecular phylogeny analysis showed that the durum TdMnSOD exhibited high amino acids sequence identity with other Mn-SOD plants. The three-dimensional structure showed that TdMnSOD forms a homotetramer and each subunit is composed of a predominantly α-helical N-terminal domain and a mixed α/β C-terminal domain. TdMnSOD gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdMnSOD enhances tolerance of the transformed yeast cells to salt, osmotic, cold and H2O2-induced oxidative stresses. Moreover, the analysis of TdMnSOD transgenic Arabidopsis plants subjected to different environmental stresses revealed low H2O2 and high proline levels as compared to the wild-type plants. Compared with the non-transformed plants, an increase in the total SOD and two other antioxidant enzyme activities including catalase (CAT) and peroxidases (POD) was observed in the three transgenic lines subjected to abiotic stress. Taken together, these data provide evidence for the involvement of durum wheat TdMnSOD in tolerance to multiple abiotic stresses in crop plants. PMID:27152457

  4. Ethylene is involved in brassinosteroids induced alternative respiratory pathway in cucumber (Cucumis sativus L. seedlings response to abiotic stress

    Directory of Open Access Journals (Sweden)

    Lijie eWei

    2015-11-01

    Full Text Available Effects of brassinosteroids (BRs on cucumber (Cucumis sativus L. abiotic stresses resistance to salt, polyethylene glycol (PEG, cold and the potential mechanisms were investigated in this work. Previous reports have indicated that BRs can induce ethylene production and enhance alternative oxidase (AOX pathway. The mechanisms whether ethylene is involved as a signal molecule which connected BR with AOX in regulating stress tolerance are still unknown. Here, we found that pretreatment with 1 µM brassinolide (BL, the most active BRs relieved stress-caused oxidative damage in cucumber seedlings and clearly enhanced the capacity of AOX and the ethylene biosynthesis. Furthermore, transcription level of ethylene signaling biosynthesis genes including ripening-related ACC synthase1 (CSACS1, ripening-related ACC synthase2 (CSACS2, ripening-related ACC synthase3 (CSACS3, 1-aminocyclopropane-1-carboxylate oxidase1 (CSACO1, 1-aminocyclopropane-1-carboxylate oxidase2 (CSACO2 and CSAOX were increased after BL treatment. Importantly, the application of the salicylhydroxamic acid (SHAM, AOX inhibitor and ethylene biosynthesis inhibitor aminooxyacetic acid (AOA decreased plant resistance to environmental stress by blocking BRs-induced alternative respiration. Taken together, our results demonstrated that ethylene was involved in BRs-induced AOX activity which played important roles in abiotic stresses tolerance in cucumber seedlings.

  5. 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. PMID:27582749

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Identiifcation of the Regulator of G-Protein Signaling Protein Responsive to Plant Hormones and Abiotic Stresses in Brassica napus

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun; ZHU Xia; ZHU Xiao-bin; YU Yi-fan; GE Hui-min; GAO Yong; LIANG Jian-sheng

    2014-01-01

    Regulator of G protein signaling proteins (RGS) accelerate the rate of GTP hydrolysis by Gαproteins, thus acting as negative regulators of G-protein signaling. Studies on Arabidopsis and soybean have proven that RGS proteins are physiologically important in plants and contribute to the signaling pathways regulated by different stimuli. Brassica napus is an important agriculturally relevant plant, the wildly planted oilseed rape in the world, which possesses an identiifed Gα, Gβand Gγsubunits. In the present study, we identiifed and characterized a Brassica napus RGS gene, BnRGS1, which contained an open reading frame of 1 380 bp encoding a putative 52.6 kDa polypeptide of 459 amino acids, within seven putative transmembrane domains in the N-terminal and RGS box in the C-terminal. BnRGS1 is located on the membrane in onion epidermal cells and tobacco leaves, and interacts with BnGA1 in the mating-based split-ubiquitin system. The expression levels of BnRGS1 were quite different in different tissues and developmental stages, and induced by abscisic acid (ABA) and indole-3-acetic acid (IAA). The effects of gibberellin (GA3) and brassinolide (BR) on the expression of BnRGS1 were irregular under the concentrations tested. Moreover, the transcript level of BnRGS1 was also induced by polyethylene glycol (PEG), whereas remained little changed by 200 mmol L-1 NaCl. These results suggested that the BnRGS1 may be involved in B. napus response to plant hormone signaling and abiotic stresses.

  9. IRE1/bZIP60-mediated unfolded protein response plays distinct roles in plant immunity and abiotic stress responses.

    Directory of Open Access Journals (Sweden)

    Adrian A Moreno

    Full Text Available Endoplasmic reticulum (ER-mediated protein secretion and quality control have been shown to play an important role in immune responses in both animals and plants. In mammals, the ER membrane-located IRE1 kinase/endoribonuclease, a key regulator of unfolded protein response (UPR, is required for plasma cell development to accommodate massive secretion of immunoglobulins. Plant cells can secrete the so-called pathogenesis-related (PR proteins with antimicrobial activities upon pathogen challenge. However, whether IRE1 plays any role in plant immunity is not known. Arabidopsis thaliana has two copies of IRE1, IRE1a and IRE1b. Here, we show that both IRE1a and IRE1b are transcriptionally induced during chemically-induced ER stress, bacterial pathogen infection and treatment with the immune signal salicylic acid (SA. However, we found that IRE1a plays a predominant role in the secretion of PR proteins upon SA treatment. Consequently, the ire1a mutant plants show enhanced susceptibility to a bacterial pathogen and are deficient in establishing systemic acquired resistance (SAR, whereas ire1b is unaffected in these responses. We further demonstrate that the immune deficiency in ire1a is due to a defect in SA- and pathogen-triggered, IRE1-mediated cytoplasmic splicing of the bZIP60 mRNA, which encodes a transcription factor involved in the expression of UPR-responsive genes. Consistently, IRE1a is preferentially required for bZIP60 splicing upon pathogen infection, while IRE1b plays a major role in bZIP60 processing upon Tunicamycin (Tm-induced stress. We also show that SA-dependent induction of UPR-responsive genes is altered in the bzip60 mutant resulting in a moderate susceptibility to a bacterial pathogen. These results indicate that the IRE1/bZIP60 branch of UPR is a part of the plant response to pathogens for which the two Arabidopsis IRE1 isoforms play only partially overlapping roles and that IRE1 has both bZIP60-dependent and bZIP60-independent

  10. EgRBP42 encoding an hnRNP-like RNA-binding protein from Elaeis guineensis Jacq. is responsive to abiotic stresses.

    Science.gov (United States)

    Yeap, Wan-Chin; Ooi, Tony Eng Keong; Namasivayam, Parameswari; Kulaveerasingam, Harikrishna; Ho, Chai-Ling

    2012-10-01

    RNA-binding proteins (RBPs) have been implicated as regulatory proteins involved in the post-transcriptional processes of gene expression in plants under various stress conditions. In this study, we report the cloning and characterization of a gene, designated as EgRBP42, encoding a member of the plant heterogeneous nuclear ribonucleoprotein (hnRNP)-like RBP family from oil palm (Elaeis guineensis Jacq.). EgRBP42 consists of two N-terminal RNA recognition motifs and a glycine-rich domain at the C-terminus. The upstream region of EgRBP42 has multiple light-responsive, stress-responsive regulatory elements and regulatory elements associated with flower development. Real-time RT-PCR analysis of EgRBP42 showed that EgRBP42 was expressed in oil palm tissues tested, including leaf, shoot apical meristem, root, female inflorescence, male inflorescence and mesocarp with the lowest transcript level in the roots. EgRBP42 protein interacted with transcripts associated with transcription, translation and stress responses using pull-down assay and electrophoretic mobility shift assay. The accumulation of EgRBP42 and its interacting transcripts were induced by abiotic stresses, including salinity, drought, submergence, cold and heat stresses in leaf discs. Collectively, the data suggested that EgRBP42 is a RBP, which responds to various abiotic stresses and could be advantageous for oil palm under stress conditions. Key message EgRBP42 may be involved in the post-transcriptional regulation of stress-related genes important for plant stress response and adaptation. PMID:22699852

  11. Cloning and analysis of expression patterns and transcriptional regulation of RghBNG in response to plant growth regulators and abiotic stresses in Rehmannia glutinosa.

    Science.gov (United States)

    Zhou, Yanqing; Zhang, Yonghua; Wei, Jun; Zhang, Yu; Li, Jingyun; Wang, Wanshen; Duan, Hongying; Chen, Juanjuan

    2015-01-01

    RghBNG, a gene of unknown function, was cloned from Rehmannia glutinosa by reverse transcription PCR and rapid amplification of cDNA ends. The full-length cDNA of RghBNG was 548 bp with a282-bp open reading frame. It encoded a polypeptide of 93 amino acids with a predicted molecular weight of 10.5 kDa and a theoretical isoelectric point of 9.25. Bioinformatics analysis indicated that RghBNG had no homology to any known plant genes, whereas the RghBNG polypeptide was highly similar to other plant proteins and possessed one conserved B12D protein family functional domain. Phylogenetic analysis revealed that RghBNG encoded for a dicot protein. RghBNG spatial and temporal expression patterns and responses to abiotic stresses and plant growth regulators were investigated by qRT-PCR. RghBNG transcripts were detected in roots, stems, leaves, petals, receptacles, stamens and pistils with the highest and lowest levels respectively observed in petals and leaves of mature plants. Additionally, RghBNG transcripts were detected at three developmental stages of roots, stems and leaves; the highest levels were observed in roots at seedling stage; Transcript levels changed to varying degrees in different tissues and stages; We also studied the effects of abiotic stress and plant growth regulators in roots and leaves. RghBNG expression was significantly increased (p plant growth regulators and abiotic stresses.

  12. Heavy-metal responsive genes in maize: identification and comparison of their expression upon various forms of abiotic stress

    International Nuclear Information System (INIS)

    To identify genes involved in defense against heavy-metal stresses, a cDNA library originating from mercuric chloride-treated maize (Zea mays L. cv. INRA 258) leaves was constructed and analysed by differential screening using cDNAs derived from treated and untreated plants. Transcriptionally activated cDNA clones, designated CHEM (chemically-activated), were isolated and characterized. They represent various known proteins, such as glycine-rich proteins, pathogenesis-related proteins, chaperones and membrane proteins. The expression of the genes encoding these proteins was studied in maize subjected to other forms of abiotic stress. Expression of glycine-rich proteins was greatly enhanced by heat stress, and also stimulated by NaCl, polluted rainwater, wounding and cold stress. Pathogenesis-related proteins were strongly induced by ultraviolet light and to a lesser extent by NaCl, polluted rainwater and wounding. Heat-shock protein was mainly induced by heat and cold, and ubiquitin by wounding. Expression of the membrane channel protein was stimulated by heat stress, NaCl, polluted rainwater and ultraviolet-light irradiation. (author)

  13. Transcriptome Profiling of the Green Alga Spirogyra pratensis (Charophyta) Suggests an Ancestral Role for Ethylene in Cell Wall Metabolism, Photosynthesis, and Abiotic Stress Responses1[OPEN

    Science.gov (United States)

    2016-01-01

    It is well known that ethylene regulates a diverse set of developmental and stress-related processes in angiosperms, yet its roles in early-diverging embryophytes and algae are poorly understood. Recently, it was shown that ethylene functions as a hormone in the charophyte green alga Spirogyra pratensis. Since land plants evolved from charophytes, this implies conservation of ethylene as a hormone in green plants for at least 450 million years. However, the physiological role of ethylene in charophyte algae has remained unknown. To gain insight into ethylene responses in Spirogyra, we used mRNA sequencing to measure changes in gene expression over time in Spirogyra filaments in response to an ethylene treatment. Our analyses show that at the transcriptional level, ethylene predominantly regulates three processes in Spirogyra: (1) modification of the cell wall matrix by expansins and xyloglucan endotransglucosylases/hydrolases, (2) down-regulation of chlorophyll biosynthesis and photosynthesis, and (3) activation of abiotic stress responses. We confirmed that the photosynthetic capacity and chlorophyll content were reduced by an ethylene treatment and that several abiotic stress conditions could stimulate cell elongation in an ethylene-dependent manner. We also found that the Spirogyra transcriptome harbors only 10 ethylene-responsive transcription factor (ERF) homologs, several of which are regulated by ethylene. These results provide an initial understanding of the hormonal responses induced by ethylene in Spirogyra and help to reconstruct the role of ethylene in ancestral charophytes prior to the origin of land plants. PMID:27489312

  14. Recent Advances in Polyamine Metabolism and Abiotic Stress Tolerance

    Directory of Open Access Journals (Sweden)

    Parimalan Rangan

    2014-01-01

    Full Text Available Global warming is an alarming problem in agriculture and its effect on yield loss has been estimated to be five per cent for every degree centigrade rise in temperature. Plants exhibit multiple mechanisms like optimizing signaling pathway, involvement of secondary messengers, production of biomolecules specifically in response to stress, modulation of various metabolic networks in accordance with stress, and so forth, in order to overcome abiotic stress factors. Many structural genes and networks of pathway were identified and reported in plant systems for abiotic stress tolerance. One such crucial metabolic pathway that is involved in normal physiological function and also gets modulated during stress to impart tolerance is polyamine metabolic pathway. Besides the role of structural genes, it is also important to know the mechanism by which these structural genes are regulated during stress. Present review highlights polyamine biosynthesis, catabolism, and its role in abiotic stress tolerance with special reference to plant systems. Additionally, a system based approach is discussed as a potential strategy to dissect the existing variation in crop species in unraveling the interacting regulatory components/genetic determinants related to PAs mediated abiotic stress tolerance.

  15. Effects of abiotic stress on plants: a systems biology perspective

    OpenAIRE

    Cramer Grant R; Urano Kaoru; Delrot Serge; Pezzotti Mario; Shinozaki Kazuo

    2011-01-01

    Abstract The natural environment for plants is composed of a complex set of abiotic stresses and biotic stresses. Plant responses to these stresses are equally complex. Systems biology approaches facilitate a multi-targeted approach by allowing one to identify regulatory hubs in complex networks. Systems biology takes the molecular parts (transcripts, proteins and metabolites) of an organism and attempts to fit them into functional networks or models designed to describe and predict the dynam...

  16. Cell wall remodeling under abiotic stress

    OpenAIRE

    Tenhaken, Raimund

    2015-01-01

    Plants exposed to abiotic stress respond to unfavorable conditions on multiple levels. One challenge under drought stress is to reduce shoot growth while maintaining root growth, a process requiring differential cell wall synthesis and remodeling. Key players in this process are the formation of reactive oxygen species (ROS) and peroxidases, which initially cross-link phenolic compounds and glycoproteins of the cell walls causing stiffening. The function of ROS shifts after having converted a...

  17. Abscisic Acid and Abiotic Stress Tolerance in Crop Plants.

    Science.gov (United States)

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

    2016-01-01

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

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

    KAUST Repository

    Alqurashi, May

    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.

  19. Safety aspects of genetically modified crops with abiotic stress tolerance

    NARCIS (Netherlands)

    Liang, C.; Prins, T.W.; Wiel, van de C.C.M.; Kok, E.J.

    2014-01-01

    Abiotic stress, such as drought, salinity, and temperature extremes, significantly reduce crop yields. Hence, development of abiotic stress-tolerant crops by modern biotechnology may contribute to global food security. Prior to introducing genetically modified crops with abiotic stress tolerance to

  20. Genome-wide analyses of the bZIP family reveal their involvement in the development, ripening and abiotic stress response in banana.

    Science.gov (United States)

    Hu, Wei; Wang, Lianzhe; Tie, Weiwei; Yan, Yan; Ding, Zehong; Liu, Juhua; Li, Meiying; Peng, Ming; Xu, Biyu; Jin, Zhiqiang

    2016-01-01

    The leucine zipper (bZIP) transcription factors play important roles in multiple biological processes. However, less information is available regarding the bZIP family in the important fruit crop banana. In this study, 121 bZIP transcription factor genes were identified in the banana genome. Phylogenetic analysis showed that MabZIPs were classified into 11 subfamilies. The majority of MabZIP genes in the same subfamily shared similar gene structures and conserved motifs. The comprehensive transcriptome analysis of two banana genotypes revealed the differential expression patterns of MabZIP genes in different organs, in various stages of fruit development and ripening, and in responses to abiotic stresses, including drought, cold, and salt. Interaction networks and co-expression assays showed that group A MabZIP-mediated networks participated in various stress signaling, which was strongly activated in Musa ABB Pisang Awak. This study provided new insights into the complicated transcriptional control of MabZIP genes and provided robust tissue-specific, development-dependent, and abiotic stress-responsive candidate MabZIP genes for potential applications in the genetic improvement of banana cultivars. PMID:27445085

  1. 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. PMID:25274312

  2. Cucumis sativus L. WAX2 Plays a Pivotal Role in Wax Biosynthesis, Influencing Pollen Fertility and Plant Biotic and Abiotic Stress Responses.

    Science.gov (United States)

    Wang, Wenjiao; Liu, Xingwang; Gai, Xinshuang; Ren, Jiaojiao; Liu, Xiaofeng; Cai, Yanling; Wang, Qian; Ren, Huazhong

    2015-07-01

    Cuticular waxes play an important part in protecting plant aerial organs from biotic and abiotic stresses. In previous studies, the biosynthetic pathway of cuticular waxes and relative functional genes has been researched and understood; however, little is known in cucumber (Cucumis sativus L.). In this study, we cloned and characterized an AtWAX2 homolog, CsWAX2, in cucumber and found that it is highly expressed in the epidermis, where waxes are synthesized, while subcellular localization showed that CsWAX2 protein is localized to the endoplasmic reticulum (ER). The transcriptional expression of CsWAX2 was found to be induced by low temperature, drought, salt stress and ABA, while the ectopic expression of CsWAX2 in an Arabidopsis wax2 mutant could partially complement the glossy stem phenotype. Abnormal expression of CsWAX2 in transgenic cucumbers specifically affected both very long chain (VLC) alkanes and cutin biosynthesis. Furthermore, transgenic cucumber plants of CsWAX2 showed significant changes in pollen viability and fruit resistance to water loss and pathogens compared with the wild type. Collectively, these results indicated that CsWAX2 plays a pivotal role in wax biosynthesis, influencing pollen fertility and the plant's response to biotic and abiotic stresses. PMID:26023108

  3. Cucumis sativus L. WAX2 Plays a Pivotal Role in Wax Biosynthesis, Influencing Pollen Fertility and Plant Biotic and Abiotic Stress Responses.

    Science.gov (United States)

    Wang, Wenjiao; Liu, Xingwang; Gai, Xinshuang; Ren, Jiaojiao; Liu, Xiaofeng; Cai, Yanling; Wang, Qian; Ren, Huazhong

    2015-07-01

    Cuticular waxes play an important part in protecting plant aerial organs from biotic and abiotic stresses. In previous studies, the biosynthetic pathway of cuticular waxes and relative functional genes has been researched and understood; however, little is known in cucumber (Cucumis sativus L.). In this study, we cloned and characterized an AtWAX2 homolog, CsWAX2, in cucumber and found that it is highly expressed in the epidermis, where waxes are synthesized, while subcellular localization showed that CsWAX2 protein is localized to the endoplasmic reticulum (ER). The transcriptional expression of CsWAX2 was found to be induced by low temperature, drought, salt stress and ABA, while the ectopic expression of CsWAX2 in an Arabidopsis wax2 mutant could partially complement the glossy stem phenotype. Abnormal expression of CsWAX2 in transgenic cucumbers specifically affected both very long chain (VLC) alkanes and cutin biosynthesis. Furthermore, transgenic cucumber plants of CsWAX2 showed significant changes in pollen viability and fruit resistance to water loss and pathogens compared with the wild type. Collectively, these results indicated that CsWAX2 plays a pivotal role in wax biosynthesis, influencing pollen fertility and the plant's response to biotic and abiotic stresses.

  4. Boron influences immune and antioxidant responses by modulating hepatic superoxide dismutase activity under calcium deficit abiotic stress in Wistar rats.

    Science.gov (United States)

    Bhasker, T Vijay; Gowda, N K S; Mondal, S; Krishnamoorthy, P; Pal, D T; Mor, A; Bhat, S Karthik; Pattanaik, A K

    2016-07-01

    The influence of Boron (B) supplementation on immune and antioxidant status of rats with or without abiotic stress induced by dietary calcium (Ca) restriction was studied in a feeding trial of 90 days. Wistar strain rats (3-4 wk age, n=84) were divided into 7 dietary groups (4 replicates of 3 each) viz., normal-calcium (100%) basal diet alone (NC, control) or supplemented with B at 5 (NCB-5), 10 (NCB-10), 20 (NCB-20) and 40ppm (NCB-40) levels; low-calcium (50%) basal diet alone (LC) or supplemented with 40ppm B (LCB-40). After 75 days of experimental feeding, rats were challenged with intraperitoneal injection of sheep RBCs to assess their humoral immunity. At the end of the trial, cell-mediated immunity was assessed as foot pad reaction to sheep RBCs injected into the hind leg paws. Eight rats from each group were sacrificed to collect blood for estimation of minerals and total antioxidant activity, and liver for superoxide dismutase gene expression analysis. Supplementation of graded levels of B (5, 10, 20 and 40ppm) as borax in NC diets significantly increased (Pcopper (Cu) and zinc (Zn) remained similar among the dietary groups, while the manganese (Mn) content was significantly decreased (P<0.01) with increased levels of dietary B. In conclusion, B supplementation increased the hepatic mRNA expression levels of both SOD isoenzymes, thereby improving the immune and antioxidant status. PMID:27259355

  5. Genome-Wide Identification, Phylogeny, and Expression Analyses of the 14-3-3 Family Reveal Their Involvement in the Development, Ripening, and Abiotic Stress Response in Banana

    Science.gov (United States)

    Li, Meiying; Ren, Licheng; Xu, Biyu; Yang, Xiaoliang; Xia, Qiyu; He, Pingping; Xiao, Susheng; Guo, Anping; Hu, Wei; Jin, Zhiqiang

    2016-01-01

    Plant 14-3-3 proteins act as critical components of various cellular signaling processes and play an important role in regulating multiple physiological processes. However, less information is known about the 14-3-3 gene family in banana. In this study, 25 14-3-3 genes were identified from the banana genome. Based on the evolutionary analysis, banana 14-3-3 proteins were clustered into ε and non-ε groups. Conserved motif analysis showed that all identified banana 14-3-3 genes had the typical 14-3-3 motif. The gene structure of banana 14-3-3 genes showed distinct class-specific divergence between the ε group and the non-ε group. Most banana 14-3-3 genes showed strong transcript accumulation changes during fruit development and postharvest ripening in two banana varieties, indicating that they might be involved in regulating fruit development and ripening. Moreover, some 14-3-3 genes also showed great changes after osmotic, cold, and salt treatments in two banana varieties, suggested their potential role in regulating banana response to abiotic stress. Taken together, this systemic analysis reveals the involvement of banana 14-3-3 genes in fruit development, postharvest ripening, and response to abiotic stress and provides useful information for understanding the functions of 14-3-3 genes in banana. PMID:27713761

  6. The α-Crystallin Domain Containing Genes: Identification, Phylogeny and Expression Profiling in Abiotic Stress, Phytohormone Response and Development in Tomato (Solanum lycopersicum).

    Science.gov (United States)

    Paul, Asosii; Rao, Sombir; Mathur, Saloni

    2016-01-01

    The α-crystallin domain (ACD) is an ancient domain conserved among all kingdoms. Plant ACD proteins have roles in abiotic stresses, transcriptional regulation, inhibiting virus movement, and DNA demethylation. An exhaustive in-silico analysis using Hidden Markov Model-based conserved motif search of the tomato proteome yielded a total of 50 ACD proteins that belonged to four groups, sub-divided further into 18 classes. One of these groups belongs to the small heat shock protein (sHSP) class of proteins, molecular chaperones implicated in heat tolerance. Both tandem and segmental duplication events appear to have shaped the expansion of this gene family with purifying selection being the primary driving force for evolution. The expression profiling of the Acd genes in two different heat stress regimes suggested that their transcripts are differentially regulated with roles in acclimation and adaptive response during recovery. The co-expression of various genes in response to different abiotic stresses (heat, low temperature, dehydration, salinity, and oxidative stress) and phytohormones (abscisic acid and salicylic acid) suggested possible cross-talk between various members to combat a myriad of stresses. Further, several genes were highly expressed in fruit, root, and flower tissues as compared to leaf signifying their importance in plant development too. Evaluation of the expression of this gene family in field grown tissues highlighted the prominent role they have in providing thermo-tolerance during daily temperature variations. The function of three putative sHSPs was established as holdase chaperones as evidenced by protection to malate-dehydrogenase against heat induced protein-aggregation. This study provides insights into the characterization of the Acd genes in tomato and forms the basis for further functional validation in-planta. PMID:27066058

  7. The α-Crystallin Domain Containing Genes: Identification, Phylogeny and Expression Profiling in Abiotic Stress, Phytohormone Response and Development in Tomato (Solanum lycopersicum

    Directory of Open Access Journals (Sweden)

    Asosii ePaul

    2016-03-01

    Full Text Available The α-crystallin domain (ACD is an ancient domain conserved among all kingdoms. Plant ACD proteins have roles in abiotic stresses, transcriptional regulation, inhibiting virus movement and DNA demethylation. An exhaustive in-silico analysis using Hidden Markof Model-based conserved motif search of the tomato proteome yielded a total of 50 ACD proteins that belonged to 4 groups, sub-divided further into18 classes. One of these groups belongs to the small heat shock protein (sHSP class of proteins, molecular chaperones implicated in heat tolerance. Both tandem and segmental duplication events appear to have shaped the expansion of this gene family with purifying selection being the primary driving force for evolution. The expression profiling of the Acd genes in two different heat stress regimes suggested that their transcripts are differentially regulated with roles in acclimation and adaptive response during recovery. The co-expression of various genes in response to different abiotic stresses (heat, low temperature, dehydration, salinity and oxidative stress and phytohormones (abscisic acid and salicylic acid suggested possible cross-talk between various members to combat a myriad of stresses. Further, several genes were highly expressed in fruit, root and flower tissues as compared to leaf signifying their importance in plant development too. Evaluation of the expression of this gene family in field grown tissues highlighted the prominent role they have in providing thermo-tolerance during daily temperature variations. The function of three putative sHSPs was established as holdase chaperones as evidenced by protection to malate-dehydrogenase against heat induced protein-aggregation. This study provides insights into the characterization of the Acd genes in tomato and forms the basis for further functional validation in-planta.

  8. 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

    Directory of Open Access Journals (Sweden)

    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

  9. 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...

  10. Cloning and functional characterization of two abiotic stress-responsive Jerusalem artichoke (Helianthus tuberosus) fructan 1-exohydrolases (1-FEHs).

    Science.gov (United States)

    Xu, Huanhuan; Liang, Mingxiang; Xu, Li; Li, Hui; Zhang, Xi; Kang, Jian; Zhao, Qingxin; Zhao, Haiyan

    2015-01-01

    Two fructan hydrolases were previously reported to exist in Jerusalem artichoke (Helianthus tuberosus) and one native fructan-β-fructosidase (1-FEH) was purified to homogeneity by SDS-PAGE, but no corresponding cDNA was cloned. Here, we cloned two full-length 1-FEH cDNA sequences from Jerusalem artichoke, named Ht1-FEH I and Ht1-FEH II, which showed high levels of identity with chicory 1-FEH I and 1-FEH II. Functional characterization of the corresponding recombinant proteins in Pichia pastoris X-33 demonstrated that both Ht1-FEHs had high levels of hydrolase activity towards β(2,1)-linked fructans, but low or no activity towards β(2,6)-linked levan and sucrose. Like other plant FEHs, the activities of the recombinant Ht1-FEHs were greatly inhibited by sucrose. Real-time quantitative PCR analysis showed that Ht1-FEH I transcripts accumulated to high levels in the developing leaves and stems of artichoke, whereas the expression levels of Ht1-FEH II increased in tubers during tuber sprouting, which implies that the two Ht1-FEHs play different roles. The levels of both Ht1-FEH I and II transcript were significantly increased in the stems of NaCl-treated plants. NaCl treatment also induced transcription of both Ht1-FEHs in the tubers, while PEG treatments slightly inhibited the expression of Ht1-FEH II in tubers. Analysis of sugar-metabolizing enzyme activities and carbohydrate concentration via HPLC showed that the enzyme activities of 1-FEHs were increased but the fructose content was decreased under NaCl and PEG treatments. Given that FEH hydrolyzes fructan to yield Fru, we discuss possible explanations for the inconsistency between 1-FEH activity and fructan dynamics in artichokes subjected to abiotic stress. PMID:25522837

  11. The auxin response factor gene family in banana: genome-wide identification and expression analyses during development, ripening, and abiotic stress.

    Science.gov (United States)

    Hu, Wei; Zuo, Jiao; Hou, Xiaowan; Yan, Yan; Wei, Yunxie; Liu, Juhua; Li, Meiying; Xu, Biyu; Jin, Zhiqiang

    2015-01-01

    Auxin signaling regulates various auxin-responsive genes via two types of transcriptional regulators, Auxin Response Factors (ARF) and Aux/IAA. ARF transcription factors act as critical components of auxin signaling that play important roles in modulating various biological processes. However, limited information about this gene family in fruit crops is currently available. Herein, 47 ARF genes were identified in banana based on its genome sequence. Phylogenetic analysis of the ARFs from banana, rice, and Arabidopsis suggested that the ARFs could be divided into four subgroups, among which most ARFs from the banana showed a closer relationship with those from rice than those from Arabidopsis. Conserved motif analysis showed that all identified MaARFs had typical DNA-binding and ARF domains, but 12 members lacked the dimerization domain. Gene structure analysis showed that the number of exons in MaARF genes ranged from 5 to 21, suggesting large variation amongst banana ARF genes. The comprehensive expression profiles of MaARF genes yielded useful information about their involvement in diverse tissues, different stages of fruit development and ripening, and responses to abiotic stresses in different varieties. Interaction networks and co-expression assays indicated the strong transcriptional response of banana ARFs and ARF-mediated networks in early fruit development for different varieties. Our systematic analysis of MaARFs revealed robust tissue-specific, development-dependent, and abiotic stress-responsive candidate MaARF genes for further functional assays in planta. These findings could lead to potential applications in the genetic improvement of banana cultivars, and yield new insights into the complexity of the control of MaARF gene expression at the transcriptional level. Finally, they support the hypothesis that ARFs are a crucial component of the auxin signaling pathway, which regulates a wide range of physiological processes. PMID:26442055

  12. The auxin response factor gene family in banana: genome-wide identification and expression analyses during development, ripening, and abiotic stress

    Directory of Open Access Journals (Sweden)

    Wei eHu

    2015-09-01

    Full Text Available Auxin signaling regulates various auxin-responsive genes via two types of transcriptional regulators, Auxin Response Factors (ARF and Aux/IAA. ARF transcription factors act as critical components of auxin signaling that play important roles in modulating various biological processes. However, limited information about this gene family in fruit crops is currently available. Herein, 47 ARF genes were identified in banana based on its genome sequence. Phylogenetic analysis of the ARFs from banana, rice, and Arabidopsis suggested that the ARFs could be divided into four subgroups, among which most ARFs from the banana showed a closer relationship with those from rice than those from Arabidopsis. Conserved motif analysis showed that all identified MaARFs had typical DNA-binding and ARF domains, but 12 members lacked the dimerization domain. Gene structure analysis showed that the number of exons in MaARF genes ranged from 5 to 21, suggesting large variation amongst banana ARF genes. The comprehensive expression profiles of MaARF genes yielded useful information about their involvement in diverse tissues, different stages of fruit development and ripening, and responses to abiotic stresses in different varieties. Interaction networks and co-expression assays indicated the strong transcriptional response of banana ARFs and ARF-mediated networks in early fruit development for different varieties. Our systematic analysis of MaARFs revealed robust tissue-specific, development-dependent, and abiotic stress-responsive candidate MaARF genes for further functional assays in planta. These findings could lead to potential applications in the genetic improvement of banana cultivars, and yield new insights into the complexity of the control of MaARF gene expression at the transcriptional level. Finally, they support the hypothesis that ARFs are a crucial component of the auxin signaling pathway, which regulates a wide range of physiological processes.

  13. Introduction of Pea DNA Helicase 45 Into Sugarcane (Saccharum spp. Hybrid) Enhances Cell Membrane Thermostability And Upregulation Of Stress-responsive Genes Leads To Abiotic Stress Tolerance.

    Science.gov (United States)

    Augustine, Sruthy Maria; Ashwin Narayan, J; Syamaladevi, Divya P; Appunu, C; Chakravarthi, M; Ravichandran, V; Tuteja, Narendra; Subramonian, N

    2015-05-01

    DNA helicases are motor proteins that play an essential role in nucleic acid metabolism, by providing a duplex-unwinding function. To improve the drought and salinity tolerance of sugarcane, a DEAD-box helicase gene isolated from pea with a constitutive promoter, Port Ubi 2.3 was transformed into the commercial sugarcane variety Co 86032 through Agrobacterium-mediated transformation, and the transgenics were screened for tolerance to soil moisture stress and salinity. The transgene integration was confirmed through polymerase chain reaction, and the V 0 transgenic events showed significantly higher cell membrane thermostability under normal irrigated conditions. The V 1 transgenic events were screened for tolerance to soil moisture stress and exhibited significantly higher cell membrane thermostability, transgene expression, relative water content, gas exchange parameters, chlorophyll content, and photosynthetic efficiency under soil moisture stress compared to wild-type (WT). The overexpression of PDH45 transgenic sugarcane also led to the upregulation of DREB2-induced downstream stress-related genes. The transgenic events demonstrated higher germination ability and better chlorophyll retention than WT under salinity stress. Our results suggest the possibility for development of increased abiotic stress tolerant sugarcane cultivars through overexpression of PDH45 gene. Perhaps this is the first report, which provides evidence for increased drought and salinity tolerance in sugarcane through overexpression of PDH45.

  14. The cowpea RING ubiquitin ligase VuDRIP interacts with transcription factor VuDREB2A for regulating abiotic stress responses.

    Science.gov (United States)

    Sadhukhan, Ayan; Panda, Sanjib Kumar; Sahoo, Lingaraj

    2014-10-01

    Cowpea (Vigna unguiculata L. Walp) is an important grain legume cultivated in drought-prone parts of the world, having higher tolerance to heat and drought than many other crops. The transcription factor, Dehydration-Responsive Element-Binding protein 2A (DREB2A), controls expression of many genes involved in osmotic and heat stress responses of plants. In Arabidopsis, DREB2A-interacting proteins (DRIPs), which function as E3 ubiquitin ligases (EC 6.3.2.19), regulate the stability of DREB2A by targeting it for proteasome-mediated degradation. In this study, we cloned the cowpea ortholog of DRIP (VuDRIP) using PCR based methods. The 1614 bp long VuDRIP mRNA encoded a protein of 433 amino acids having a C3HC4-type Really Interesting New Gene (RING) domain in the N-terminus and a C-terminal conserved region, similar to Arabidopsis DRIP1 and DRIP2. We found VuDRIP up-regulation in response to various abiotic stresses and phytohormones. Using yeast (Saccharomyces cerevisae) two-hybrid analysis, VuDRIP was identified as a VuDREB2A-interacting protein. The results indicate negative regulation of VuDREB2A by ubiquitin ligases in cowpea similar to Arabidopsis along with their other unknown roles in stress and hormone signaling pathways. PMID:25090086

  15. Chemical Priming of Plants Against Multiple Abiotic Stresses: Mission Possible?

    Science.gov (United States)

    Savvides, Andreas; Ali, Shawkat; Tester, Mark; Fotopoulos, Vasileios

    2016-04-01

    Crop plants are subjected to multiple abiotic stresses during their lifespan that greatly reduce productivity and threaten global food security. Recent research suggests that plants can be primed by chemical compounds to better tolerate different abiotic stresses. Chemical priming is a promising field in plant stress physiology and crop stress management. We review here promising chemical agents such as sodium nitroprusside, hydrogen peroxide, sodium hydrosulfide, melatonin, and polyamines that can potentially confer enhanced tolerance when plants are exposed to multiple abiotic stresses. The challenges and opportunities of chemical priming are addressed, with the aim to boost future research towards effective application in crop stress management.

  16. Chemical Priming of Plants Against Multiple Abiotic Stresses: Mission Possible?

    Science.gov (United States)

    Savvides, Andreas; Ali, Shawkat; Tester, Mark; Fotopoulos, Vasileios

    2016-04-01

    Crop plants are subjected to multiple abiotic stresses during their lifespan that greatly reduce productivity and threaten global food security. Recent research suggests that plants can be primed by chemical compounds to better tolerate different abiotic stresses. Chemical priming is a promising field in plant stress physiology and crop stress management. We review here promising chemical agents such as sodium nitroprusside, hydrogen peroxide, sodium hydrosulfide, melatonin, and polyamines that can potentially confer enhanced tolerance when plants are exposed to multiple abiotic stresses. The challenges and opportunities of chemical priming are addressed, with the aim to boost future research towards effective application in crop stress management. PMID:26704665

  17. Chemical Priming of Plants Against Multiple Abiotic Stresses: Mission Possible?

    KAUST Repository

    Savvides, Andreas

    2015-12-15

    Crop plants are subjected to multiple abiotic stresses during their lifespan that greatly reduce productivity and threaten global food security. Recent research suggests that plants can be primed by chemical compounds to better tolerate different abiotic stresses. Chemical priming is a promising field in plant stress physiology and crop stress management. We review here promising chemical agents such as sodium nitroprusside, hydrogen peroxide, sodium hydrosulfide, melatonin, and polyamines that can potentially confer enhanced tolerance when plants are exposed to multiple abiotic stresses. The challenges and opportunities of chemical priming are addressed, with the aim to boost future research towards effective application in crop stress management.

  18. Expression profiles of 12 late embryogenesis abundant protein genes from Tamarix hispida in response to abiotic stress.

    Science.gov (United States)

    Gao, Caiqiu; Liu, Yali; Wang, Chao; Zhang, Kaimin; Wang, Yucheng

    2014-01-01

    Twelve embryogenesis abundant protein (LEA) genes (named ThLEA-1 to -12) were cloned from Tamarix hispida. The expression profiles of these genes in response to NaCl, PEG, and abscisic acid (ABA) in roots, stems, and leaves of T. hispida were assessed using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). These ThLEAs all showed tissue-specific expression patterns in roots, stems, and leaves under normal growth conditions. However, they shared a high similar expression patterns in the roots, stems, and leaves when exposed to NaCl and PEG stress. Furthermore, ThLEA-1, -2, -3, -4, and -11 were induced by NaCl and PEG, but ThLEA-5, -6, -8, -10, and -12 were downregulated by salt and drought stresses. Under ABA treatment, some ThLEA genes, such as ThLEA-1, -2, and -3, were only slightly differentially expressed in roots, stems, and leaves, indicating that they may be involved in the ABA-independent signaling pathway. These findings provide a basis for the elucidation of the function of LEA genes in future work. PMID:25133264

  19. Genome-Wide Analysis of C2H2 Zinc-Finger Family Transcription Factors and Their Responses to Abiotic Stresses in Poplar (Populus trichocarpa.

    Directory of Open Access Journals (Sweden)

    Quangang Liu

    Full Text Available C2H2 zinc-finger (C2H2-ZF proteins are a large gene family in plants that participate in various aspects of normal plant growth and development, as well as in biotic and abiotic stress responses. To date, no overall analysis incorporating evolutionary history and expression profiling of the C2H2-ZF gene family in model tree species poplar (Populus trichocarpa has been reported.Here, we identified 109 full-length C2H2-ZF genes in P. trichocarpa, and classified them into four groups, based on phylogenetic analysis. The 109 C2H2-ZF genes were distributed unequally on 19 P. trichocarpa linkage groups (LGs, with 39 segmental duplication events, indicating that segmental duplication has been important in the expansion of the C2H2-ZF gene family. Promoter cis-element analysis indicated that most of the C2H2-ZF genes contain phytohormone or abiotic stress-related cis-elements. The expression patterns of C2H2-ZF genes, based on heatmap analysis, suggested that C2H2-ZF genes are involved in tissue and organ development, especially root and floral development. Expression analysis based on quantitative real-time reverse transcription polymerase chain reaction indicated that C2H2-ZF genes are significantly involved in drought, heat and salt response, possibly via different mechanisms.This study provides a thorough overview of the P. trichocarpa C2H2-ZF gene family and presents a new perspective on the evolution of this gene family. In particular, some C2H2-ZF genes may be involved in environmental stress tolerance regulation. PtrZFP2, 19 and 95 showed high expression levels in leaves and/or roots under environmental stresses. Additionally, this study provided a solid foundation for studying the biological roles of C2H2-ZF genes in Populus growth and development. These results form the basis for further investigation of the roles of these candidate genes and for future genetic engineering and gene functional studies in Populus.

  20. Calcium-Mediated Abiotic Stress Signaling in Roots.

    Science.gov (United States)

    Wilkins, Katie A; Matthus, Elsa; Swarbreck, Stéphanie M; Davies, Julia M

    2016-01-01

    Roots are subjected to a range of abiotic stresses as they forage for water and nutrients. Cytosolic free calcium is a common second messenger in the signaling of abiotic stress. In addition, roots take up calcium both as a nutrient and to stimulate exocytosis in growth. For calcium to fulfill its multiple roles must require strict spatio-temporal regulation of its uptake and efflux across the plasma membrane, its buffering in the cytosol and its sequestration or release from internal stores. This prompts the question of how specificity of signaling output can be achieved against the background of calcium's other uses. Threats to agriculture such as salinity, water availability and hypoxia are signaled through calcium. Nutrient deficiency is also emerging as a stress that is signaled through cytosolic free calcium, with progress in potassium, nitrate and boron deficiency signaling now being made. Heavy metals have the capacity to trigger or modulate root calcium signaling depending on their dose and their capacity to catalyze production of hydroxyl radicals. Mechanical stress and cold stress can both trigger an increase in root cytosolic free calcium, with the possibility of membrane deformation playing a part in initiating the calcium signal. This review addresses progress in identifying the calcium transporting proteins (particularly channels such as annexins and cyclic nucleotide-gated channels) that effect stress-induced calcium increases in roots and explores links to reactive oxygen species, lipid signaling, and the unfolded protein response. PMID:27621742

  1. Genetic improvement of rice for biotic and abiotic stress tolerance

    OpenAIRE

    ANSARI, MAHMOOD UR RAHMAN; Shaheen, Tayyaba; BUKHARI, SHAZAI; Husnain, Tayyab

    2015-01-01

    Rice (Oryza sativa L.) is among the most important food crops that provide a staple food for nearly half of the world's population. Rice crops are prone to various types of stresses, both biotic and abiotic. Biotic stresses include insect pests, fungus, bacteria, viruses, and herbicide toxicity. Among abiotic stresses, drought, cold, and salinity are also well studied in rice. Various genes have been identified, cloned, and characterized to combat these stresses and protect rice crops. T...

  2. Phenotyping for Abiotic Stress Tolerance in Maize

    Institute of Scientific and Technical Information of China (English)

    Benhilda Masuka; Jose Luis Araus; Biswanath Das; Kai Sonder; Jill E. Cairns

    2012-01-01

    The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change.Molecular breeding offers the tools to accelerate cereal breeding; however,suitable phenotyping protocols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized.To facilitate the full potential of molecular tools,greater emphasis needs to be given to reducing the within-experimental site variability,application of stress and characterization of the environment and appropriate phenotyping tools.Yield is a function of many processes throughout the plant cycle,and thus integrative traits that encompass crop performance over time or organization level (i.e.canopy level) will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process.Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status.Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen.

  3. HOS3, an ELO-Like Gene, Inhibits Effects of ABA and Implicates a S-1-P/Ceramide Control System for Abiotic Stress Responses in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Tanya M. Quist; Irina Sokolchik; Huazhong Shi; Robert J. Joly; Ray A. Bressan; Albino Maggio; Meena Narsimhan; Xia Li

    2009-01-01

    A hyper-osmotically sensitive mutant of Arabidopsis thaliana, designated hos3-1 (high expression of osmotically responsive genes), was identified based on its hyper-luminescence of RD29A:LUC promoter fusion plants upon treatment with NaCI and ABA. These responses implicate the disrupted gene as a direct or indirect negative regulator of the RD29A stress-responsive pathway. By sequencing the flanking regions of the T-DNA borders, it was determined that the disrupted gene is at locus At4g36830, annotated as encoding a putative protein with high homology to CIG30 (ELO2/FEN1).CIG30 has been implicated in synthesis of very long chain fatty acids (VLCFA), which are essential precursors for sphingolipids and ceramides. Altered stress responses characteristic of ABA-hypersensitivity, including reduced root growth inhibition and reduced germination with ABA treatment and reduced water loss from leaves, were exhibited by allelic hos3-1 and hos3-2 mutants. The hos3-2 mutant is partially suppressed in its transcript abundance and is inherited as a recessive trait. Further, the HOS30RF under the control of the 35SCaMV promoter restored wild-type NaCI- and ABA-root growth sensitivity as well as RD29A:LUC luminescence in mutant plants. We also show here that the HOS3 wild-type gene functionally complements the sensitivity of elo2 and elo3 yeast mutants to monensin. Furthermore, both hos3-1 and hos3-2 alleles shared increased sensitivity to the herbicide Metolachlor, which inhibits acyl chain elongation in synthesis of VLCFA, and HOS3 functionally complemented both elo2 and elo3 and restored levels of VLCFA. Together, these data establish that HOS3 inhibits ABA-mediated stress responses and implicate the VLCFA pathway and products as control points for several aspects of abiotic stress signaling and responses. The results also provide support for a role of ceramide in the control of stomatal behavior.

  4. Composition of the SAGA complex in plants and its role in controlling gene expression in response to abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Felipe eMoraga

    2015-10-01

    Full Text Available Protein complexes involved in epigenetic regulation of transcription have evolved as molecular strategies to face environmental stress in plants. SAGA (Spt–Ada–Gcn5 Acetyltransferase is a transcriptional co-activator complex that regulates numerous cellular processes through the coordination of multiple post-translational histone modifications, including acetylation, deubiquitination, and chromatin recognition. The diverse functions of the SAGA complex involve distinct modules that are highly conserved between yeast, flies, and mammals. In this review, the composition of the SAGA complex in plants is described and its role in gene expression regulation under stress conditions summarized. Some of these proteins are likely involved in the regulation of the inducible expression of genes under light, cold, drought, salt, and iron stress, although the functions of several of its components remain unknown.

  5. Hydrogen sulfide regulates abiotic stress tolerance and biotic stress resistance in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Haitao Shi; Tiantian Ye; Ning Han; Hongwu Bian; Xiaodong Liu; Zhulong Chan

    2015-01-01

    Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated expressions of two cysteine desulfhydrases, and exogenous H2S donor (sodium hydrosulfide, NaHS) and H2S scavenger (hypotaurine, HT) pre-treated plants were used to dissect the involvement of H2S in plant stress responses. The cysteine desulfhydrases overexpressing plants and NaHS pre-treated plants exhibited higher endogenous H2S level and improved abiotic stress tolerance and biotic stress resistance, while cysteine desulfhydrases knockdown plants and HT pre-treated plants displayed lower endogenous H2S level and decreased stress resistance. Moreover, H2S upregulated the transcripts of multiple abiotic and biotic stress-related genes, and inhibited reactive oxygen species (ROS) accumulation. Interest-ingly, MIR393-mediated auxin signaling including MIR393a/b and their target genes (TIR1, AFB1, AFB2, and AFB3) was transcrip-tional y regulated by H2S, and was related with H2S-induced antibacterial resistance. Moreover, H2S regulated 50 carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines. Taken together, these results indicated that cysteine desulfhydrase and H2S conferred abiotic stress tolerance and biotic stress resistance, via affecting the stress-related gene expressions, ROS metabolism, metabolic homeostasis, and MIR393-targeted auxin receptors.

  6. Hydrogen sulfide regulates abiotic stress tolerance and biotic stress resistance in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Han, Ning; Bian, Hongwu; Liu, Xiaodong; Chan, Zhulong

    2015-07-01

    Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated expressions of two cysteine desulfhydrases, and exogenous H2S donor (sodium hydrosulfide, NaHS) and H2S scavenger (hypotaurine, HT) pre-treated plants were used to dissect the involvement of H2S in plant stress responses. The cysteine desulfhydrases overexpressing plants and NaHS pre-treated plants exhibited higher endogenous H2S level and improved abiotic stress tolerance and biotic stress resistance, while cysteine desulfhydrases knockdown plants and HT pre-treated plants displayed lower endogenous H2S level and decreased stress resistance. Moreover, H2S upregulated the transcripts of multiple abiotic and biotic stress-related genes, and inhibited reactive oxygen species (ROS) accumulation. Interestingly, MIR393-mediated auxin signaling including MIR393a/b and their target genes (TIR1, AFB1, AFB2, and AFB3) was transcriptionally regulated by H2S, and was related with H2S-induced antibacterial resistance. Moreover, H2S regulated 50 carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines. Taken together, these results indicated that cysteine desulfhydrase and H2S conferred abiotic stress tolerance and biotic stress resistance, via affecting the stress-related gene expressions, ROS metabolism, metabolic homeostasis, and MIR393-targeted auxin receptors.

  7. Hydrogen sulfide regulates abiotic stress tolerance and biotic stress resistance in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Han, Ning; Bian, Hongwu; Liu, Xiaodong; Chan, Zhulong

    2015-07-01

    Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated expressions of two cysteine desulfhydrases, and exogenous H2S donor (sodium hydrosulfide, NaHS) and H2S scavenger (hypotaurine, HT) pre-treated plants were used to dissect the involvement of H2S in plant stress responses. The cysteine desulfhydrases overexpressing plants and NaHS pre-treated plants exhibited higher endogenous H2S level and improved abiotic stress tolerance and biotic stress resistance, while cysteine desulfhydrases knockdown plants and HT pre-treated plants displayed lower endogenous H2S level and decreased stress resistance. Moreover, H2S upregulated the transcripts of multiple abiotic and biotic stress-related genes, and inhibited reactive oxygen species (ROS) accumulation. Interestingly, MIR393-mediated auxin signaling including MIR393a/b and their target genes (TIR1, AFB1, AFB2, and AFB3) was transcriptionally regulated by H2S, and was related with H2S-induced antibacterial resistance. Moreover, H2S regulated 50 carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines. Taken together, these results indicated that cysteine desulfhydrase and H2S conferred abiotic stress tolerance and biotic stress resistance, via affecting the stress-related gene expressions, ROS metabolism, metabolic homeostasis, and MIR393-targeted auxin receptors. PMID:25329496

  8. Regulation of Translation Initiation under Biotic and Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    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.

  9. Three TaFAR genes function in the biosynthesis of primary alcohols and the response to abiotic stresses in Triticum aestivum.

    Science.gov (United States)

    Wang, Meiling; Wang, Yong; Wu, Hongqi; Xu, Jing; Li, Tingting; Hegebarth, Daniela; Jetter, Reinhard; Chen, Letian; Wang, Zhonghua

    2016-01-01

    Cuticular waxes play crucial roles in protecting plants against biotic and abiotic stresses. They are complex mixtures of very-long-chain fatty acids and their derivatives, including C20-C32 fatty alcohols. Here, we report the identification of 32 FAR-like genes and the detailed characterization of TaFAR2, TaFAR3 and TaFAR4, wax biosynthetic genes encoding fatty acyl-coenzyme A reductase (FAR) in wheat leaf cuticle. Heterologous expression of the three TaFARs in wild-type yeast and mutated yeast showed that TaFAR2, TaFAR3 and TaFAR4 were predominantly responsible for the accumulation of C18:0, C28:0 and C24:0 primary alcohols, respectively. Transgenic expression of the three TaFARs in tomato fruit and Arabidopsis cer4 mutant led to increased production of C22:0-C30:0 primary alcohols. GFP-fusion protein injection assay showed that the three encoded TaFAR proteins were localized to the endoplasmic reticulum (ER), the site of wax biosynthesis. The transcriptional expression of the three TaFAR genes was induced by cold, salt, drought and ABA. Low air humidity led to increased expression of TaFAR genes and elevated wax accumulation in wheat leaves. Collectively, these data suggest that TaFAR2, TaFAR3 and TaFAR4 encode active alcohol-forming FARs involved in the synthesis of primary alcohol in wheat leaf and the response to environmental stresses. PMID:27112792

  10. Characterization of reference genes for RT-qPCR in the desert moss Syntrichia caninervis in response to abiotic stress and desiccation/rehydration

    OpenAIRE

    Li, Xiaoshuang; Zhang, Daoyuan; Li, Haiyan; Gao, Bei; Yang, Honglan; Zhang, Yuanming; Wood, Andrew J.

    2015-01-01

    Syntrichia caninervis is the dominant bryophyte of the biological soil crusts found in the Gurbantunggut desert. The extreme desert environment is characterized by prolonged drought, temperature extremes, high radiation and frequent cycles of hydration and dehydration. S. caninervis is an ideal organism for the identification and characterization of genes related to abiotic stress tolerance. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) expression analysis i...

  11. High-quality reference genes for quantifying the transcriptional responses of Oryza sativa L.(ssp.indica and japonica) to abiotic stress conditions

    Institute of Scientific and Technical Information of China (English)

    MAKSUP Sarunyaporn; SUPAIBULWATANA Kanyaratt; SELVARAJ Gopalan

    2013-01-01

    Rice (Oryza sativa L.) is important to food security and is also an excellent model plant for numerous cereal crops.A functional genomics study in rice includes characterization of the expression dynamics of genes by quantitative real-time PCR (qPCR) analysis; this is a significant key for developing rice varieties that perform well in the face of adverse climate change.The qPCR analysis requires the use of appropriate reference genes in order to make any quantitative interpretations meaningful.Here,the new potential reference genes were selected from a huge public database of rice microarray experiments.The expression stability of 14 candidates and 4 conventional reference genes was validated by geNormPLUs and NormFinder software.Seven candidates are superior to the conventionally used reference genes in qPCR and three genes can be used reliably for quantitating the expression of genes involved in abiotic stress responses.These high-quality references EP (LOC_Os05g08980),HNR (LOC_Os01g71770),and TBC (LOC_Os09g34040) worked very well in three indica genotypes and one japonica genotype.One of indica genotypes including the Jasmine rice,KDML105 developed in Thailand for which no reference genes have been reported until now.

  12. The rice RCN11 gene encodes β1,2-xylosyltransferase and is required for plant responses to abiotic stresses and phytohormones.

    Science.gov (United States)

    Takano, Sho; Matsuda, Shuichi; Funabiki, Atsushi; Furukawa, Jun-ichi; Yamauchi, Takaki; Tokuji, Yoshihiko; Nakazono, Mikio; Shinohara, Yasuro; Takamure, Itsuro; Kato, Kiyoaki

    2015-07-01

    Seed germination rates and plant development and growth under abiotic stress are important aspects of crop productivity. Here, our characterization of the rice (Oryza sativa L.) mutant reduced culm number11 (rcn11) showed that RCN11 controls growth of plants exposed to abnormal temperature, salinity and drought conditions. RCN11 also mediates root aerenchyma formation under oxygen-deficient conditions and ABA sensitivity during seed germination. Molecular studies showed that the rcn11 mutation resulted from a 966-bp deletion that caused loss of function of β1,2-xylosyltransferase (OsXylT). This enzyme is located in the Golgi apparatus where it catalyzes the transfer of xylose from UDP-xylose to the core β-linked mannose of N-glycans. RCN11/OsXylT promoter activity was observed in the basal part of the shoot containing the shoot and axillary meristems and in the base of crown roots. The level of RCN11/OsXylT expression was regulated by multiple phytohormones and various abiotic stresses suggesting that plant specific N-glycosylation is regulated by multiple signals in rice plants. The present study is the first to demonstrate that rice β1,2-linked xylose residues on N-glycans are critical for seed germination and plant development and growth under conditions of abiotic stress. PMID:26025522

  13. Global expression profiling of rice microRNAs by one-tube stem-loop reverse transcription quantitative PCR revealed important roles of microRNAs in abiotic stress responses.

    Science.gov (United States)

    Shen, Jianqiang; Xie, Kabin; Xiong, Lizhong

    2010-12-01

    MicroRNAs are a class of endogenous small RNA molecules (20-24 nucleotides) that have pivotal roles in regulating gene expression mostly at posttranscriptional levels in plants. Plant microRNAs have been implicated in the regulation of diverse biological processes including growth and stress responses. However, the information about microRNAs in regulating abiotic stress responses in rice is limited. We optimized a one-tube stem-loop reverse transcription quantitative PCR (ST-RT qPCR) for high-throughput expression profiling analysis of microRNAs in rice under normal and stress conditions. The optimized ST-RT qPCR method was as accurate as small RNA gel blotting and was more convenient and time-saving than other methods in quantifying microRNAs. With this method, 41 rice microRNAs were quantified for their relative expression levels after drought, salt, cold, and abscisic acid (ABA) treatments. Thirty-two microRNAs showed induced or suppressed expression after stress or ABA treatment. Further analysis suggested that stress-responsive cis-elements were enriched in the promoters of stress-responsive microRNA genes. The expressions of five and seven microRNAs were significantly affected in the rice plant with defects in stress tolerance regulatory genes OsSKIPa and OsbZIP23, respectively. Some of the predicted target genes of these microRNAs were also related to abiotic stresses. We conclude that ST-RT qPCR is an efficient and reliable method for expression profiling of microRNAs and a significant portion of rice microRNAs participate in abiotic stress response and regulation.

  14. Stress-responsive expression patterns and functional characterization of cold shock domain proteins in cabbage (Brassica rapa) under abiotic stress conditions.

    Science.gov (United States)

    Choi, Min Ji; Park, Ye Rin; Park, Su Jung; Kang, Hunseung

    2015-11-01

    Although the functional roles of cold shock domain proteins (CSDPs) have been demonstrated during the growth, development, and stress adaptation of Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa), and wheat (Triticum aestivum), the functions of CSDPs in other plants species, including cabbage (Brassica rapa), are largely unknown. To gain insight into the roles of CSDPs in cabbage under stress conditions, the genes encoding CSDPs in cabbage were isolated, and the functional roles of CSDPs in response to environmental stresses were analyzed. Real-time RT-PCR analysis revealed that the levels of BrCSDP transcripts increased during cold, salt, or drought stress, as well as upon ABA treatment. Among the five BrCSDP genes found in the cabbage genome, one CSDP (BRU12051), named BrCSDP3, was unique in that it is localized to the chloroplast as well as to the nucleus. Ectopic expression of BrCSDP3 in Arabidopsis resulted in accelerated seed germination and better seedling growth compared to the wild-type plants under high salt or dehydration stress conditions, and in response to ABA treatment. BrCSDP3 did not affect the splicing of intron-containing genes and processing of rRNAs in the chloroplast. BrCSDP3 had the ability to complement RNA chaperone-deficient Escherichia coli mutant cells under low temperatures as well as DNA- and RNA-melting abilities, suggesting that it possesses RNA chaperone activity. Taken together, these results suggest that BrCSDP3, harboring RNA chaperone activity, plays a role as a positive regulator in seed germination and seedling growth under stress conditions. PMID:26263516

  15. Mitigating abiotic stress in crop plants by microorganisms

    OpenAIRE

    Milošević Nada A.; Marinković Jelena B.; Tintor Branislava B.

    2012-01-01

    Microorganisms could play an important role in adaptation strategies and increase of tolerance to abiotic stresses in agricultural plants. Plant-growth-promoting rhizobacteria (PGPR) mitigate most effectively the impact of abiotic stresses (drought, low temperature, salinity, metal toxicity, and high temperatures) on plants through the production of exopolysaccharates and biofilm formation. PGPR mitigate the impact of drought on plants through a process so-called induced systemic tolera...

  16. The tomato DWD motif-containing protein DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase and plays a pivotal role in abiotic stress responses

    International Nuclear Information System (INIS)

    Highlights: • We identify DDI1 as a DAMAGED DNA BINDING PROTEIN1 (DDB1)-interacting protein. • DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase in the nucleus. • DDI1 plays a positive role in regulating abiotic stress response in tomato. - Abstract: CULLIN4(CUL4)–DAMAGED DNA BINDING PROTEIN1 (DDB1)-based ubiquitin ligase plays significant roles in multiple physiological processes via ubiquitination-mediated degradation of relevant target proteins. The DDB1–CUL4-associated factor (DCAF) acts as substrate receptor in the CUL4–DDB1 ubiquitin ligase complex and determines substrate specificity. In this study, we identified a tomato (Solanum lycopersicum) DDB1-interacting (DDI1) protein as a DCAF protein involved in response to abiotic stresses, including UV radiation, high salinity and osmotic stress. Co-immunoprecipitation and bimolecular fluorescence complementation assay indicated that DDI1 associates with CUL4–DDB1 in the nucleus. Quantitative RT-PCR analysis indicated the DDI1 gene is induced by salt, mannitol and UV-C treatment. Moreover, transgenic tomato plants with overexpression or knockdown of the DDI1 gene exhibited enhanced or attenuated tolerance to salt/mannitol/UV-C, respectively. Thus, our data suggest that DDI1 functions as a substrate receptor of the CUL4–DDB1 ubiquitin ligase, positively regulating abiotic stress response in tomato

  17. The tomato DWD motif-containing protein DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase and plays a pivotal role in abiotic stress responses

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Min [Ministry of Education Key Laboratory for Bio-resource and Eco-environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064 (China); School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China); Department of Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339 (United States); Zhu, Yunye [School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China); Qiao, Maiju [Ministry of Education Key Laboratory for Bio-resource and Eco-environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064 (China); Tang, Xiaofeng [Ministry of Education Key Laboratory for Bio-resource and Eco-environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064 (China); School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China); Zhao, Wei [School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China); Xiao, Fangming [Department of Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339 (United States); Liu, Yongsheng, E-mail: liuyongsheng1122@hfut.edu.cn [Ministry of Education Key Laboratory for Bio-resource and Eco-environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610064 (China); School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China)

    2014-08-08

    Highlights: • We identify DDI1 as a DAMAGED DNA BINDING PROTEIN1 (DDB1)-interacting protein. • DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase in the nucleus. • DDI1 plays a positive role in regulating abiotic stress response in tomato. - Abstract: CULLIN4(CUL4)–DAMAGED DNA BINDING PROTEIN1 (DDB1)-based ubiquitin ligase plays significant roles in multiple physiological processes via ubiquitination-mediated degradation of relevant target proteins. The DDB1–CUL4-associated factor (DCAF) acts as substrate receptor in the CUL4–DDB1 ubiquitin ligase complex and determines substrate specificity. In this study, we identified a tomato (Solanum lycopersicum) DDB1-interacting (DDI1) protein as a DCAF protein involved in response to abiotic stresses, including UV radiation, high salinity and osmotic stress. Co-immunoprecipitation and bimolecular fluorescence complementation assay indicated that DDI1 associates with CUL4–DDB1 in the nucleus. Quantitative RT-PCR analysis indicated the DDI1 gene is induced by salt, mannitol and UV-C treatment. Moreover, transgenic tomato plants with overexpression or knockdown of the DDI1 gene exhibited enhanced or attenuated tolerance to salt/mannitol/UV-C, respectively. Thus, our data suggest that DDI1 functions as a substrate receptor of the CUL4–DDB1 ubiquitin ligase, positively regulating abiotic stress response in tomato.

  18. ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses.

    Science.gov (United States)

    Cheung, Ming-Yan; Li, Xiaorong; Miao, Rui; Fong, Yu-Hang; Li, Kwan-Pok; Yung, Yuk-Lin; Yu, Mei-Hui; Wong, Kam-Bo; Chen, Zhongzhou; Lam, Hon-Ming

    2016-03-01

    G proteins are involved in almost all aspects of the cellular regulatory pathways through their ability to bind and hydrolyze GTP. The YchF subfamily, interestingly, possesses the unique ability to bind both ATP and GTP, and is possibly an ancestral form of G proteins based on phylogenetic studies and is present in all kingdoms of life. However, the biological significance of such a relaxed ligand specificity has long eluded researchers. Here, we have elucidated the different conformational changes caused by the binding of a YchF homolog in rice (OsYchF1) to ATP versus GTP by X-ray crystallography. Furthermore, by comparing the 3D relationships of the ligand position and the various amino acid residues at the binding sites in the crystal structures of the apo-bound and ligand-bound versions, a mechanism for the protein's ability to bind both ligands is revealed. Mutation of the noncanonical G4 motif of the OsYchF1 to the canonical sequence for GTP specificity precludes the binding/hydrolysis of ATP and prevents OsYchF1 from functioning as a negative regulator of plant-defense responses, while retaining its ability to bind/hydrolyze GTP and its function as a negative regulator of abiotic stress responses, demonstrating the specific role of ATP-binding/hydrolysis in disease resistance. This discovery will have a significant impact on our understanding of the structure-function relationships of the YchF subfamily of G proteins in all kingdoms of life. PMID:26912459

  19. ATP binding by the P-loop NTPase OsYchF1 (an unconventional G protein) contributes to biotic but not abiotic stress responses.

    Science.gov (United States)

    Cheung, Ming-Yan; Li, Xiaorong; Miao, Rui; Fong, Yu-Hang; Li, Kwan-Pok; Yung, Yuk-Lin; Yu, Mei-Hui; Wong, Kam-Bo; Chen, Zhongzhou; Lam, Hon-Ming

    2016-03-01

    G proteins are involved in almost all aspects of the cellular regulatory pathways through their ability to bind and hydrolyze GTP. The YchF subfamily, interestingly, possesses the unique ability to bind both ATP and GTP, and is possibly an ancestral form of G proteins based on phylogenetic studies and is present in all kingdoms of life. However, the biological significance of such a relaxed ligand specificity has long eluded researchers. Here, we have elucidated the different conformational changes caused by the binding of a YchF homolog in rice (OsYchF1) to ATP versus GTP by X-ray crystallography. Furthermore, by comparing the 3D relationships of the ligand position and the various amino acid residues at the binding sites in the crystal structures of the apo-bound and ligand-bound versions, a mechanism for the protein's ability to bind both ligands is revealed. Mutation of the noncanonical G4 motif of the OsYchF1 to the canonical sequence for GTP specificity precludes the binding/hydrolysis of ATP and prevents OsYchF1 from functioning as a negative regulator of plant-defense responses, while retaining its ability to bind/hydrolyze GTP and its function as a negative regulator of abiotic stress responses, demonstrating the specific role of ATP-binding/hydrolysis in disease resistance. This discovery will have a significant impact on our understanding of the structure-function relationships of the YchF subfamily of G proteins in all kingdoms of life.

  20. 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 ch

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

    Science.gov (United States)

    Ramu, Vemanna S; Paramanantham, Anjugam; Ramegowda, Venkategowda; Mohan-Raju, Basavaiah; Udayakumar, Makarla; Senthil-Kumar, Muthappa

    2016-01-01

    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.

  2. Characterization of reference genes for RT-qPCR in the desert moss Syntrichia caninervis in response to abiotic stress and desiccation/rehydration

    Science.gov (United States)

    Li, Xiaoshuang; Zhang, Daoyuan; Li, Haiyan; Gao, Bei; Yang, Honglan; Zhang, Yuanming; Wood, Andrew J.

    2015-01-01

    Syntrichia caninervis is the dominant bryophyte of the biological soil crusts found in the Gurbantunggut desert. The extreme desert environment is characterized by prolonged drought, temperature extremes, high radiation and frequent cycles of hydration and dehydration. S. caninervis is an ideal organism for the identification and characterization of genes related to abiotic stress tolerance. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) expression analysis is a powerful analytical technique that requires the use of stable reference genes. Using available S. caninervis transcriptome data, we selected 15 candidate reference genes and analyzed their relative expression stabilities in S. caninervis gametophores exposed to a range of abiotic stresses or a hydration-desiccation-rehydration cycle. The programs geNorm, NormFinder, and RefFinder were used to assess and rank the expression stability of the 15 candidate genes. The stability ranking results of reference genes under each specific experimental condition showed high consistency using different algorithms. For abiotic stress treatments, the combination of two genes (α-TUB2 and CDPK) were sufficient for accurate normalization. For the hydration-desiccation-rehydration process, the combination of two genes (α-TUB1 and CDPK) were sufficient for accurate normalization. 18S was among the least stable genes in all of the experimental sets and was unsuitable as reference gene in S. caninervis. This is the first systematic investigation and comparison of reference gene selection for RT-qPCR work in S. caninervis. This research will facilitate gene expression studies in S. caninervis, related moss species from the Syntrichia complex and other mosses. PMID:25699066

  3. Nitric oxide, stomatal closure, and abiotic stress.

    Science.gov (United States)

    Neill, Steven; Barros, Raimundo; Bright, Jo; Desikan, Radhika; Hancock, John; Harrison, Judith; Morris, Peter; Ribeiro, Dimas; Wilson, Ian

    2008-01-01

    Various data indicate that nitric oxide (NO) is an endogenous signal in plants that mediates responses to several stimuli. Experimental evidence in support of such signalling roles for NO has been obtained via the application of NO, usually in the form of NO donors, via the measurement of endogenous NO, and through the manipulation of endogenous NO content by chemical and genetic means. Stomatal closure, initiated by abscisic acid (ABA), is effected through a complex symphony of intracellular signalling in which NO appears to be one component. Exogenous NO induces stomatal closure, ABA triggers NO generation, removal of NO by scavengers inhibits stomatal closure in response to ABA, and ABA-induced stomatal closure is reduced in mutants that are impaired in NO generation. The data indicate that ABA-induced guard cell NO generation requires both nitric oxide synthase-like activity and, in Arabidopsis, the NIA1 isoform of nitrate reductase (NR). NO stimulates mitogen-activated protein kinase (MAPK) activity and cGMP production. Both these NO-stimulated events are required for ABA-induced stomatal closure. ABA also stimulates the generation of H2O2 in guard cells, and pharmacological and genetic data demonstrate that NO accumulation in these cells is dependent on such production. Recent data have extended this model to maize mesophyll cells where the induction of antioxidant defences by water stress and ABA required the generation of H2O2 and NO and the activation of a MAPK. Published data suggest that drought and salinity induce NO generation which activates cellular processes that afford some protection against the oxidative stress associated with these conditions. Exogenous NO can also protect cells against oxidative stress. Thus, the data suggest an emerging model of stress responses in which ABA has several ameliorative functions. These include the rapid induction of stomatal closure to reduce transpirational water loss and the activation of antioxidant defences

  4. Identification of Cassava MicroRNAs under Abiotic Stress.

    Science.gov (United States)

    Ballén-Taborda, Carolina; Plata, Germán; Ayling, Sarah; Rodríguez-Zapata, Fausto; Becerra Lopez-Lavalle, Luis Augusto; Duitama, Jorge; Tohme, Joe

    2013-01-01

    The study of microRNAs (miRNAs) in plants has gained significant attention in recent years due to their regulatory role during development and in response to biotic and abiotic stresses. Although cassava (Manihot esculenta Crantz) is tolerant to drought and other adverse conditions, most cassava miRNAs have been predicted using bioinformatics alone or through sequencing of plants challenged by biotic stress. Here, we use high-throughput sequencing and different bioinformatics methods to identify potential cassava miRNAs expressed in different tissues subject to heat and drought conditions. We identified 60 miRNAs conserved in other plant species and 821 potential cassava-specific miRNAs. We also predicted 134 and 1002 potential target genes for these two sets of sequences. Using real time PCR, we verified the condition-specific expression of 5 cassava small RNAs relative to a non-stress control. We also found, using publicly available expression data, a significantly lower expression of the predicted target genes of conserved and nonconserved miRNAs under drought stress compared to other cassava genes. Gene Ontology enrichment analysis along with condition specific expression of predicted miRNA targets, allowed us to identify several interesting miRNAs which may play a role in stress-induced posttranscriptional regulation in cassava and other plants. PMID:24328029

  5. Identification of Cassava MicroRNAs under Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Carolina Ballén-Taborda

    2013-01-01

    Full Text Available The study of microRNAs (miRNAs in plants has gained significant attention in recent years due to their regulatory role during development and in response to biotic and abiotic stresses. Although cassava (Manihot esculenta Crantz is tolerant to drought and other adverse conditions, most cassava miRNAs have been predicted using bioinformatics alone or through sequencing of plants challenged by biotic stress. Here, we use high-throughput sequencing and different bioinformatics methods to identify potential cassava miRNAs expressed in different tissues subject to heat and drought conditions. We identified 60 miRNAs conserved in other plant species and 821 potential cassava-specific miRNAs. We also predicted 134 and 1002 potential target genes for these two sets of sequences. Using real time PCR, we verified the condition-specific expression of 5 cassava small RNAs relative to a non-stress control. We also found, using publicly available expression data, a significantly lower expression of the predicted target genes of conserved and nonconserved miRNAs under drought stress compared to other cassava genes. Gene Ontology enrichment analysis along with condition specific expression of predicted miRNA targets, allowed us to identify several interesting miRNAs which may play a role in stress-induced posttranscriptional regulation in cassava and other plants.

  6. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest their Role in Abiotic Stress Response

    Directory of Open Access Journals (Sweden)

    Annapurna eBhattacharjee

    2016-05-01

    Full Text Available Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22 and OsHOX24. These genes were highly upregulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA, auxin, salicylic acid and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/TATTG and AH2 (CAAT(C/GATTG. Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses.

  7. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest Their Role in Abiotic Stress Response.

    Science.gov (United States)

    Bhattacharjee, Annapurna; Khurana, Jitendra P; Jain, Mukesh

    2016-01-01

    Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22, and OsHOX24. These genes were highly up-regulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA), auxin, salicylic acid, and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/T)ATTG) and AH2 (CAAT(C/G)ATTG). Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses. PMID:27242831

  8. Ecogenomics of plant resistance to biotic and abiotic stresses

    NARCIS (Netherlands)

    Davila Olivas, N.H.

    2016-01-01

    Summary

    In natural and agricultural ecosystems, plants are exposed to a wide diversity of abiotic and biotic stresses such as drought, salinity, pathogens and insect herbivores. Under natural conditions, these stresses do not occur in isolation but commonly occur simultaneo

  9. Progress in research of dehydrin response to abiotic stress%非生物胁迫下植物脱水素的研究进展

    Institute of Scientific and Technical Information of China (English)

    马杰; 刘翠芳; 李灵之; 向建华; 陈信波

    2012-01-01

    脱水素是LEA蛋白中的一类,广泛存在于植物的各个组织器官及植物胚胎发育后期.脱水素是植物在受低温、干旱和高盐等非生物逆境胁迫时合成的一类高亲水性保护蛋白,具有保护核酸、胞内蛋白和膜结构免受损害的功能.许多研究已经证实在非生物胁迫下,植物脱水素的表达与积累和植物抗逆性之间存在着紧密的联系.对脱水素的结构、亚细胞定位、基因表达模式及非生物胁迫下脱水素作用的最新研究成果进行了综述.%Dehydrins, known as a group of late embryogenesis abundant (LEA) proteins, are present in all plant organs and during late embryogenesis. Dehydrins have extremely hydrophilicity and are produced to protect plants from structural and molecular damage caused by abiotic stresses like low temperature, drought and salt stress. The positive correlation between the accumulation of dehydrin and abiotic stress tolerance in plants was reported. This review summarized the current knowledge about the structural characters, sub-cellular localization and gene expression of dehydrins and the functions in plant stress tolerance.

  10. Simultaneous expression of abiotic stress responsive transcription factors, AtDREB2A, AtHB7 and AtABF3 improves salinity and drought tolerance in peanut (Arachis hypogaea L..

    Directory of Open Access Journals (Sweden)

    Vittal Pruthvi

    Full Text Available Drought, salinity and extreme temperatures are the most common abiotic stresses, adversely affecting plant growth and productivity. Exposure of plants to stress activates stress signalling pathways that induce biochemical and physiological changes essential for stress acclimation. Stress tolerance is governed by multiple traits, and importance of a few traits in imparting tolerance has been demonstrated. Under drought, traits linked to water mining and water conservation, water use efficiency and cellular tolerance (CT to desiccation are considered to be relevant. In this study, an attempt has been made to improve CT in drought hardy crop, peanut (Arachis hypogaea L., cv. TMV2 by co-expressing stress-responsive transcription factors (TFs, AtDREB2A, AtHB7 and AtABF3, associated with downstream gene expression. Transgenic plants simultaneously expressing these TFs showed increased tolerance to drought, salinity and oxidative stresses compared to wild type, with an increase in total plant biomass. The transgenic plants exhibited improved membrane and chlorophyll stability due to enhanced reactive oxygen species scavenging and osmotic adjustment by proline synthesis under stress. The improvement in stress tolerance in transgenic lines were associated with induced expression of various CT related genes like AhGlutaredoxin, AhAldehyde reductase, AhSerine threonine kinase like protein, AhRbx1, AhProline amino peptidase, AhHSP70, AhDIP and AhLea4. Taken together the results indicate that co-expression of stress responsive TFs can activate multiple CT pathways, and this strategy can be employed to improve abiotic stress tolerance in crop plants.

  11. Mitigating abiotic stress in crop plants by microorganisms

    Directory of Open Access Journals (Sweden)

    Milošević Nada A.

    2012-01-01

    Full Text Available Microorganisms could play an important role in adaptation strategies and increase of tolerance to abiotic stresses in agricultural plants. Plant-growth-promoting rhizobacteria (PGPR mitigate most effectively the impact of abiotic stresses (drought, low temperature, salinity, metal toxicity, and high temperatures on plants through the production of exopolysaccharates and biofilm formation. PGPR mitigate the impact of drought on plants through a process so-called induced systemic tolerance (IST, which includes: a bacterial production of cytokinins, b production of antioxidants and c degradation of the ethylene precursor ACC by bacterial ACC deaminase. Symbiotic fungi (arbuscular mycorrhizal fungi and dual symbiotic systems (endophytic rhizospheric bacteria and symbiotic fungi also tend to mitigate the abiotic stress in plants.

  12. The LysM Receptor-Like Kinase LysM RLK1 Is Required to Activate Defense and Abiotic-Stress Responses Induced by Overexpression of Fungal Chitinases in Arabidopsis Plants

    Institute of Scientific and Technical Information of China (English)

    Yariv Brotman; Ada Viterbo; Udi Landau; Smadar Pnini; Jan Lisec; Salma Balazadeh; Bernd Mueller-Roeber; Aviah Zilberstein; Lothar Willmitzer; Ilan Chet

    2012-01-01

    Application of crab shell chitin or pentamer chitin oligosaccharide to Arabidopsis seedlings increased tolerance to salinity in wild-type but not in knockout mutants of the LysM Receptor-Like Kinase1 (CERK1/LysM RLK1) gene,known to play a critical role in signaling defense responses induced by exogenous chitin.Arabidopsis plants overexpressing the endochitinase chit36 and hexoaminidase excy1 genes from the fungus Trichoderma asperelleoides T203 showed increased tolerance to salinity,heavy-metal stresses,and Botrytis cinerea infection.Resistant lines,overexpressing fungal chitinases at different levels,were outcrossed to lysm rlk1 mutants.Independent homozygous hybrids lost resistance to biotic and abiotic stresses,despite enhanced chitinase activity.Expression analysis of 270 stress-related genes,including those induced by reactive oxygen species (ROS) and chitin,revealed constant up-regulation (at least twofold) of 10 genes in the chitinase-overexpressing line and an additional 76 salt-induced genes whose expression was not elevated in the lysm rlk1 knockout mutant or the hybrids harboring the mutation.These findings elucidate that chitin-induced signaling mediated by LysM RLK1 receptor is not limited to biotic stress response but also encompasses abiotic-stress signaling and can be conveyed by ectopic expression of chitinases in plants.

  13. 植物DNA甲基化变异对生物和非生物胁迫的响应机制%DNA Methylation Variation of Biological and Abiotic Stress Response Mechanism in Plant

    Institute of Scientific and Technical Information of China (English)

    王晓凤; 曾凡锁; 詹亚光

    2011-01-01

    高等植物具有复杂的机制使其对环境的变化做出响应,这种机制是通过长期进化建立起来的.它们能够对出现的生物和非生物胁迫产生响应.在分子水平上,植物对各种胁迫的响应是受多基因表达变化调控的,包括植物激素水杨酸、脱落酸等信号途径在整合、协调植物胁迫过程中起关键作用.近年来的研究表明,在植物响应胁迫这一过程中还进行着表观遗传调控这一进程.我们简要综述了生物胁迫和非生物胁迫对表观遗传的影响以及胁迫印记的产生,并讨论了植物响应胁迫的表观遗传调控机制.%Plants have complex mechanisms to respond to environmental changes, such a mechanism is established through long-term evolution. They can response to biological and abiotic stress. At the molecular level, plants of various stress response are regulated by multiple gene expression, including the plant hormone salicylic acid, ABA signaling pathways in the integration, coordination of plant stress play a key role in the process. Recent studies showed that plant responses to stress are also engaged in the process of epigenetic regulation in this process. In this paper we reviewed the biological stress and abiotic stress on the impact of epigenetic imprint stress generation,and discussed the plant response to stress epigenetic mechanisms.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Influence of abiotic stress during soybean germination followed by recovery on the phenolic compounds of radicles and their antioxidant capacity

    OpenAIRE

    Sylwia Swigonska; Ryszard Amarowicz; Angelika Król; Agnieszka Mostek; Anna Badowiec; Stanisław Weidner

    2014-01-01

    Abiotic stress factors are among the major causes of lower crop yields. It is known, that in response to cold and/or osmotic stress, crops activate various defense mechanisms, including morphological, physiological and metabolic adaptations. Secondary metabolism, especially phenolic compounds, seem to be an important factor of stress-induced metabolic re-engineering as their levels are alternated by abiotic stress in plants. Despite the fact, that the nature and function of phenolic compounds...

  16. Cloning of PEPC-1 from a C4 halophyte Suaeda aralocaspica without Kranz anatomy and its recombinant enzymatic activity in responses to abiotic stresses.

    Science.gov (United States)

    Cheng, Gang; Wang, Lu; Lan, Haiyan

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) is a key enzyme of C4 photosynthetic pathway and plays an important biochemical role in higher plants and micro organisms. To gain understanding of the role of PEPC in stress adaptation in plant, we cloned PEPC gene from Suaeda aralocaspica, a C4 species without Kranz anatomy, and performed a series of experiments with PEPC gene expressed in Escherichia coli under various abiotic stresses. Results showed that, based on the homology cloning and 5'-RACE technique, the full-length cDNA sequence of PEPC (2901 bp) from S. aralocaspica was obtained, which shares the typical conserved domains to documented PEPCs and was identified as PEPC-1 in accord to the reported partial sequence (ppc-1) in S. aralocaspica. qRT-PCR analysis revealed the expression patterns of PEPC-1 and PEPC-2 (known as ppc-2, another plant type of PEPC) in S. aralocaspica, suggesting that PEPC-1 was up-regulated during seed germination and under NaCl stress, and presented higher level in chlorenchyma than other tissues, which were significantly different with PEPC-2. Afterwards, PEPC-1 was recombinant in E. coli (pET-28a-PEPC) and expressed as an approximate 110 kDa protein. Under various abiotic stresses, the recombinant E. coli strain harboring with PEPC-1 showed significant advantage in growth at 400-800 mmol L(-1) NaCl, 10-20% PEG6000, 25 and 30 °C lower temperature, 50-200 μmol L(-1) methyl viologen, and pH 5.0 and 9.0 condition, compared to control. Further analysis of the enzymatic characteristics of the recombinant PEPC-1 suggests that it was the higher enzyme activity of PEPC-1 which might confer the stress tolerance to E. coli. We speculate that over expression of PEPC-1 is probably related to regulation of oxaloacetate (OAA) in tricarboxylic acid (TCA) cycle in E. coli, which may contribute to further understanding of the physiological function of PEPC in S. aralocaspica. PMID:26777251

  17. 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.

  18. Differential expression profiles of poplar MAP kinase kinases in response to abiotic stresses and plant hormones, and overexpression of PtMKK4 improves the drought tolerance of poplar.

    Science.gov (United States)

    Wang, Lei; Su, Hongyan; Han, Liya; Wang, Chuanqi; Sun, Yanlin; Liu, Fenghong

    2014-07-15

    Mitogen-activated protein kinase (MAPK) cascades are universal signal transduction modules that play essential roles in plant growth, development and stress response. MAPK kinases (MAPKKs), which link MAPKs and MAPKK kinases (MAPKKKs), are integral in mediating various stress responses in plants. However, to date few data about the roles of poplar MAPKKs in stress signal transduction are available. In this study, we performed a systemic analysis of poplar MAPKK gene family expression profiles in response to several abiotic stresses and stress-associated hormones. Furthermore, Populus trichocarpa MAPKK4 (PtMKK4) was chosen for functional characterization. Transgenic analysis showed that overexpression of the PtMKK4 gene remarkably enhanced drought stress tolerance in the transgenic poplar plants. The PtMKK4-overexpressing plants also exhibited much lower levels of H2O2 and higher antioxidant enzyme activity after exposure to drought stress compared to the wide type lines. Besides, some drought marker genes including PtP5CS, PtSUS3, PtLTP3 and PtDREB8 exhibited higher expression levels in the transgenic lines than in the wide type under drought conditions. This study provided valuable information for understanding the putative functions of poplar MAPKKs involved in important signaling pathways under different stress conditions.

  19. Mechanism of Plant Response to Abiotic Stresses Regulated by AP2/ERF Proteins%AP2/ERF蛋白调控植物的非生物胁迫应答机制

    Institute of Scientific and Technical Information of China (English)

    杨德鑫; 周时荣; 权瑞党; 黄荣峰

    2012-01-01

    The AP2/ERF proteins, one family of plant-specific transcription factors, invole in plant growth and development, and regulate plant resistance to biotic and abiotic stresses. Studies have shown that AP2/ERF proteins could not only form a complex transcriptional regulatory network with other types of transcription factors to regulate the expression of functional genes through multiple signal transduction pathways, but also regulate plant abiotic stresses as sensing factor of external signal. This paper reviews the progress on studying AP2/ERF proteins in response to abiotic stress, including plant hormone synthesis, wax synthesis, hypoxia stress response, ROS scavenging and protein modification, etc. , and prospects the research orientations in the future.%AP2/ERF蛋白是植物所特有的转录因子,参与植物生长发育以及调控生物和非生物胁迫反应.研究表明,AP2/ERF蛋白不仅与其它类型转录因子共同形成复杂的转录调控网络,通过多种信号转导途径调控功能基因的表达,而且可以作为外界信号的感应因子调控植物的非生物胁迫应答.主要从AP2/ERF蛋白在植物激素合成、蜡质合成、低氧胁迫应答、ROS清除以及蛋白质修饰等方面综述了AP2/ERF蛋白在植物非生物胁迫应答中的研究进展,并展望了今后的研究方向.

  20. Roles of ERF Transcription Factors in Biotic and Abiotic Stress Response in Plants%ERF转录因子在植物对生物和非生物胁迫反应中的作用

    Institute of Scientific and Technical Information of China (English)

    莫纪波; 李大勇; 张慧娟; 宋凤鸣

    2011-01-01

    The ethylene responsive factors (ERF) belong to a subfamily of the AP2/ERF superfamily in plants. The ERF family was defined by the presence of a conserved ERF domain consisting of 58 or 59 amino acids and has been demonstrated to be widely involved in regulation of various aspects of plant growth and development as well as in responses to different abiotic and biotic stresses. In this minireview, we summarize the functions and mechanisms of the ERF transcription factors in regulation of responses to abiotic and biotic stresses and discuss the future directions of studies on the ERF transcription factors in plants.%ERF (ethylene responsive factor)转录因子是植物AP2/ERF转录因子超家族的一个亚家族,其特征是蛋白序列中含有一个高度保守的58或59个氨基酸组成的ERF结构域,广泛参与植物生长发育及各种逆境胁迫反应的调控.文章简要介绍ERF转录因子在植物抗生物和非生物胁迫反应中的作用及其可能机制,并讨论了今后的研究重点.

  1. Research Progress of ERF Transcription Factors in Plant Biotic and Abiotic Stress Responses%ERF 转录因子在植物抗逆境胁迫的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘建光; 王永强; 张寒霜; 赵俊丽; 郭娴; 孟宪鹏

    2013-01-01

    ERF( Ethylene responsive factors )转录因子广泛存在于各类植物中,通过识别和结合不同的顺式元件参与植物逆境胁迫的应答。主要介绍ERF转录因子结构特征及其功能特性,在植物应答生物和非生物的胁迫中可能的调控机制,并讨论了今后的研究重点。%Ethylene responsive factors ( ERF) transcription factors primary exist in many kinds of plants ,they play an important role in plant biotic and abiotic stress responses by recognition and binding the different cis -acting element.In this review,we introduce the structure features and functional characterization of the ERF transcription factors,possible regulatory mechanism in plant biotic and abiotic stress responses and discuss the future directions of studies on the ERF transcription factors in plants .

  2. 逆境条件下烟草维生素B6存在形态的变化%Changes of the Existing Forms of Vitamin B6 in Tobacco in Response to Abiotic Stress

    Institute of Scientific and Technical Information of China (English)

    王灵红; 黄龙全; 张剑韵

    2013-01-01

    维生素B6(VB6)是一类吡啶化合物的总称.以组培烟草为材料,采用高效液相色谱结合荧光检测技术,分析紫外线、低温、盐和弱光胁迫对烟草体内VB6各存在形态含量的影响.结果表明:逆境条件下,VB6各存在形态含量发生变化,其中以磷酸吡哆醛和吡哆醇含量升高最明显.%Vitamin B6(VB6)is the general term for a kind of pyridine compounds.The paper aims to study the changes of the existing forms of vitamin B6 in response to abiotic stress.In this experiment,the influence of UV-B,chilling,salt and weak light stress on the content of the existing forms of VB6 in tobacco plants was determined using HPLC with fluorescence detector.The results showed that in response to abiotic stress,the content of the existing forms of VB6 changed with pyridoxal 5'-phosphate and pyridoxine increased most obviously.

  3. Biotic and abiotic stress can induce cystatin expression in chestnut.

    Science.gov (United States)

    Pernas, M; Sánchez-Monge, R; Salcedo, G

    2000-02-11

    A cysteine proteinase inhibitor (cystatin) from chestnut (Castanea sativa) seeds, designated CsC, has been previously characterized. Its antifungal, acaricide and inhibitory activities have allowed to involve CsC in defence mechanisms. The CsC transcription levels decreased during seed maturation and increased throughout germination, an opposite behavior to that shown by most phytocystatins. No inhibition of endogenous proteinase activity by purified CsC was found during the seed maturation or germination processes. CsC message accumulation was induced in chestnut leaves after fungal infection, as well as by wounding and jasmonic acid treatment. Induction in roots was also observed by the last two treatments. Furthermore, CsC transcript levels strongly raised, both in roots and leaves, when chestnut plantlets were subjected to cold- and saline-shocks, and also in roots by heat stress. All together, these data suggest that chestnut cystatin is not only involved in defence responses to pests and pathogen invasion, but also in those related to abiotic stress.

  4. Review of recent transgenic studies on abiotic stress tolerance and future molecular breeding in potato

    OpenAIRE

    Kikuchi, Akira; Huynh, Huu Duc; Endo, Tsukasa; Watanabe, Kazuo

    2015-01-01

    Global warming has become a major issue within the last decade. Traditional breeding programs for potato have focused on increasing productivity and quality and disease resistance, thus, modern cultivars have limited tolerance of abiotic stresses. The introgression of abiotic stress tolerance into modern cultivars is essential work for the future. Recently, many studies have investigated abiotic stress using transgenic techniques. This manuscript focuses on the study of abiotic stress, in par...

  5. Screening for Abiotic Stress Tolerance in Rice: Salt, Cold, and Drought.

    Science.gov (United States)

    Almeida, Diego M; Almadanim, M Cecília; Lourenço, Tiago; Abreu, Isabel A; Saibo, Nelson J M; Oliveira, M Margarida

    2016-01-01

    Rice (Oryza sativa) is the primary source of food for more than half of the world population. Most rice varieties are severely injured by abiotic stresses, with strong social and economic impact. Understanding rice responses to stress may help breeding for more tolerant varieties. However, papers dealing with stress experiments often describe very different experimental designs, thus making comparisons difficult. The use of identical setups is the only way to generate comparable data. This chapter is organized into three sections, describing the experimental conditions established at the Genomics of Plant Stress (GPlantS) unit of ITQB to assess the response of rice plants to three different abiotic stresses--high salinity, cold stress, and drought. All sections include a detailed description of the materials and methodology, as well as useful notes gathered from the GPlantS team's experience. We use rice seedlings as plants at this stage show high sensitivity to abiotic stresses. For the salt and cold stress assays we use hydroponic cultures, while for the drought assay plants are grown in soil and subjected to water withholding. All setups enable visual score determination and are suitable for sample collection along the imposition of stress. The proposed methodologies are simple and affordable to implement in most labs, allowing the discrimination of several rice genotypes at the molecular and phenotypic level. PMID:26867623

  6. Biological Networks Underlying Abiotic Stress Tolerance in Temperate Crops—A Proteomic Perspective

    Directory of Open Access Journals (Sweden)

    Klára Kosová

    2015-09-01

    Full Text Available Abiotic stress factors, especially low temperatures, drought, and salinity, represent the major constraints limiting agricultural production in temperate climate. Under the conditions of global climate change, the risk of damaging effects of abiotic stresses on crop production increases. Plant stress response represents an active process aimed at an establishment of novel homeostasis under altered environmental conditions. Proteins play a crucial role in plant stress response since they are directly involved in shaping the final phenotype. In the review, results of proteomic studies focused on stress response of major crops grown in temperate climate including cereals: common wheat (Triticum aestivum, durum wheat (Triticum durum, barley (Hordeum vulgare, maize (Zea mays; leguminous plants: alfalfa (Medicago sativa, soybean (Glycine max, common bean (Phaseolus vulgaris, pea (Pisum sativum; oilseed rape (Brassica napus; potato (Solanum tuberosum; tobacco (Nicotiana tabaccum; tomato (Lycopersicon esculentum; and others, to a wide range of abiotic stresses (cold, drought, salinity, heat, imbalances in mineral nutrition and heavy metals are summarized. The dynamics of changes in various protein functional groups including signaling and regulatory proteins, transcription factors, proteins involved in protein metabolism, amino acid metabolism, metabolism of several stress-related compounds, proteins with chaperone and protective functions as well as structural proteins (cell wall components, cytoskeleton are briefly overviewed. Attention is paid to the differences found between differentially tolerant genotypes. In addition, proteomic studies aimed at proteomic investigation of multiple stress factors are discussed. In conclusion, contribution of proteomic studies to understanding the complexity of crop response to abiotic stresses as well as possibilities to identify and utilize protein markers in crop breeding processes are discussed.

  7. DREB1/CBF transcription factors: their structure, function and role in abiotic stress tolerance in plants

    Indian Academy of Sciences (India)

    M. Akhtar; A. Jaiswal; G. Taj; J. P. Jaiswal; M. I. Qureshi; N. K. Singh

    2012-12-01

    Drought, high salinity and low temperature are major abiotic stresses that influence survival, productivity and geographical distribution of many important crops across the globe. Plants respond to these environmental challenges via physiological, cellular and molecular processes, which results in adjusted metabolic and structural alterations. The dehydration-responsive-element-binding (DREB) protein / C-repeat binding factors (CBFs) belong to APETALA2 (AP2) family transcription factors that bind to DRE/CRT cis-element and regulate the expression of stress-responsive genes. DREB1/CBF genes, therefore, play an important role in increasing stress tolerance in plants and their deployment using transgenic technology seems to be a potential alternative in management of abiotic stresses in crop plants. This review is mainly focussed on the structural characteristics as well as transcriptional regulation of gene expression in response to various abiotic stresses, with particular emphasis on the role of DREB1/CBF regulon in stress-responsive gene expression. The recent progress related to genetic engineering of DREB1/CBF transcription factors in various crops and model plants is also summarized.

  8. Autophagy, a Conserved Mechanism for Protein Degradation, Responds to Heat, and Other Abiotic Stresses in Capsicum annuum L.

    Science.gov (United States)

    Zhai, Yufei; Guo, Meng; Wang, Hu; Lu, Jinping; Liu, Jinhong; Zhang, Chong; Gong, Zhenhui; Lu, Minghui

    2016-01-01

    Abiotic stresses negatively affect plants growth and development by inducing protein denaturation, and autophagy degrades the damaged proteins to alleviate their toxicity, however, little is known about the involvement of autophagy in pepper (Capsicum annuum L.) tolerances to abiotic stresses. In this study, we identified autophagy-related gene (ATG) members in the whole genome of pepper by HMM method and analyzed their expression profiles in response to heat and other abiotic stresses by quantitative real-time PCR. The results showed that the CaATG contained 15 core ATG members including 29 ATG proteins with their respective conserved functional domains, involving the whole process of autophagy. Under normal environmental condition, the expression of CaATG genes showed tissue- and developmental stage-specific patterns, while under abiotic stresses of salt, drought, heat, cold and carbohydrate starvation, the accumulation of autophagosome punctate increased and the expression level of CaATG genes changed with stress type-dependent pattern, which indicates the linkage of autophagy in pepper response to abiotic stresses. After treated with heat stress, both the number of up-regulated CaATG genes and the increment of autophagosome punctate were higher in pepper thermotolerant line R9 than those in thermosensitive line B6, implying an association of autophagy with heat tolerance. In addition, CaATG6 was predicted to interact with CaHSP90 family members. Our study suggests that autophagy is connected to pepper tolerances to heat and other abiotic stresses. PMID:26904087

  9. Autophagy, a conserved mechanism for protein degradation, responds to heat and other abiotic stresses in Capsicum annuum L.

    Directory of Open Access Journals (Sweden)

    Yufei eZhai

    2016-02-01

    Full Text Available Abiotic stresses negatively affect plants growth and development by inducing protein denaturation, and autophagy degrades the damaged proteins to alleviate their toxicity, however, little is known about the involvement of autophagy in pepper (Capsicum annuum L. tolerances to abiotic stresses. In this study, we identified autophagy-related gene (ATG members in the whole genome of pepper by HMM method and analyzed their expression profiles in response to heat and other abiotic stresses by quantitative real-time PCR. The results showed that the CaATG contained 15 core ATG members including 29 ATG proteins with their respective conserved functional domains, involving the whole process of autophagy. Under normal environmental condition, the expression of CaATG genes showed tissue- and developmental stage-specific patterns, while under abiotic stresses of salt, drought, heat, cold and carbohydrate starvation, the accumulation of autophagosome punctate increased and the expression level of CaATG genes changed with stress type-dependent pattern, which indicates the linkage of autophagy in pepper response to abiotic stresses. After treated with heat stress, both the number of up-regulated CaATG genes and the increment of autophagosome punctate were higher in pepper thermotolerant line R9 than those in thermosensitive line B6, implying an association of autophagy with heat tolerance. In addition, CaATG6 was predicted to interact with CaHSP90 family members. Our study suggests that autophagy is connected to pepper tolerances to heat and other abiotic stresses.

  10. Novel NAC transcription factor TaNAC67 confers enhanced multi-abiotic stress tolerances in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Xinguo Mao

    Full Text Available Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. NAC transcription factors play pivotal roles in abiotic stress signaling in plants. As a staple crop, wheat production is severely constrained by abiotic stresses whereas only a few NAC transcription factors have been characterized functionally. To promote the application of NAC genes in wheat improvement by biotechnology, a novel NAC gene designated TaNAC67 was characterized in common wheat. To determine its role, transgenic Arabidopsis overexpressing TaNAC67-GFP controlled by the CaMV-35S promoter was generated and subjected to various abiotic stresses for morphological and physiological assays. Gene expression showed that TaNAC67 was involved in response to drought, salt, cold and ABA treatments. Localization assays revealed that TaNAC67 localized in the nucleus. Morphological analysis indicated the transgenics had enhanced tolerances to drought, salt and freezing stresses, simultaneously supported by enhanced expression of multiple abiotic stress responsive genes and improved physiological traits, including strengthened cell membrane stability, retention of higher chlorophyll contents and Na(+ efflux rates, improved photosynthetic potential, and enhanced water retention capability. Overexpression of TaNAC67 resulted in pronounced enhanced tolerances to drought, salt and freezing stresses, therefore it has potential for utilization in transgenic breeding to improve abiotic stress tolerance in crops.

  11. Genome-wide identification of BURP domain-containing genes in rice reveals a gene family with diverse structures and responses to abiotic stresses.

    Science.gov (United States)

    Ding, Xipeng; Hou, Xin; Xie, Kabin; Xiong, Lizhong

    2009-06-01

    Increasing evidence suggests that a gene family encoding proteins containing BURP domains have diverse functions in plants, but systematic characterization of this gene family have not been reported. In this study, 17 BURP family genes (OsBURP01-17) were identified and analyzed in rice (Oryza sativa L.). These genes have diverse exon-intron structures and distinct organization of putative motifs. Based on the phylogenetic analysis of BURP protein sequences from rice and other plant species, the BURP family was classified into seven subfamilies, including two subfamilies (BURP V and BURP VI) with members from rice only and one subfamily (BURP VII) with members from monocotyledons only. Two BURP gene clusters, belonging to BURP V and BURP VI, were located in the duplicated region on chromosome 5 and 6 of rice, respectively. Transcript level analysis of BURP genes of rice in various tissues and organs revealed different tempo-spatial expression patterns, suggesting that these genes may function at different stages of plant growth and development. Interestingly, all the genes of the BURP VII subfamily were predominantly expressed in flower organs. We also investigated the expression patterns of BURP genes of rice under different stress conditions. The results suggested that, except for two genes (OsBURP01 and OsBURP13), all other members were induced by at least one of the stresses including drought, salt, cold, and abscisic acid treatment. Two genes (OsBURP05 and OsBURP16) were responsive to all the stress treatments and most of the OsBURP genes were responsive to salt stress. Promoter sequence analysis revealed an over-abundance of stress-related cis-elements in the stress-responsive genes. The data presented here provide important clues for elucidating the functions of genes of this family. PMID:19363683

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

    Science.gov (United States)

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

    2016-01-01

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

  13. Enhancing crop resilience to combined abiotic and biotic stress through the dissection of physiological and molecular crosstalk.

    Science.gov (United States)

    Kissoudis, Christos; van de Wiel, Clemens; Visser, Richard G F; van der Linden, Gerard

    2014-01-01

    Plants growing in their natural habitats are often challenged simultaneously by multiple stress factors, both abiotic and biotic. Research has so far been limited to responses to individual stresses, and understanding of adaptation to combinatorial stress is limited, but indicative of non-additive interactions. Omics data analysis and functional characterization of individual genes has revealed a convergence of signaling pathways for abiotic and biotic stress adaptation. Taking into account that most data originate from imposition of individual stress factors, this review summarizes these findings in a physiological context, following the pathogenesis timeline and highlighting potential differential interactions occurring between abiotic and biotic stress signaling across the different cellular compartments and at the whole plant level. Potential effects of abiotic stress on resistance components such as extracellular receptor proteins, R-genes and systemic acquired resistance will be elaborated, as well as crosstalk at the levels of hormone, reactive oxygen species, and redox signaling. Breeding targets and strategies are proposed focusing on either manipulation and deployment of individual common regulators such as transcription factors or pyramiding of non- (negatively) interacting components such as R-genes with abiotic stress resistance genes. We propose that dissection of broad spectrum stress tolerance conferred by priming chemicals may provide an insight on stress cross regulation and additional candidate genes for improving crop performance under combined stress. Validation of the proposed strategies in lab and field experiments is a first step toward the goal of achieving tolerance to combinatorial stress in crops.

  14. Enhancing crop resilience to combined abiotic and biotic stress through the dissection of physiological and molecular crosstalk.

    Science.gov (United States)

    Kissoudis, Christos; van de Wiel, Clemens; Visser, Richard G F; van der Linden, Gerard

    2014-01-01

    Plants growing in their natural habitats are often challenged simultaneously by multiple stress factors, both abiotic and biotic. Research has so far been limited to responses to individual stresses, and understanding of adaptation to combinatorial stress is limited, but indicative of non-additive interactions. Omics data analysis and functional characterization of individual genes has revealed a convergence of signaling pathways for abiotic and biotic stress adaptation. Taking into account that most data originate from imposition of individual stress factors, this review summarizes these findings in a physiological context, following the pathogenesis timeline and highlighting potential differential interactions occurring between abiotic and biotic stress signaling across the different cellular compartments and at the whole plant level. Potential effects of abiotic stress on resistance components such as extracellular receptor proteins, R-genes and systemic acquired resistance will be elaborated, as well as crosstalk at the levels of hormone, reactive oxygen species, and redox signaling. Breeding targets and strategies are proposed focusing on either manipulation and deployment of individual common regulators such as transcription factors or pyramiding of non- (negatively) interacting components such as R-genes with abiotic stress resistance genes. We propose that dissection of broad spectrum stress tolerance conferred by priming chemicals may provide an insight on stress cross regulation and additional candidate genes for improving crop performance under combined stress. Validation of the proposed strategies in lab and field experiments is a first step toward the goal of achieving tolerance to combinatorial stress in crops. PMID:24904607

  15. Enhancing crop resilience to combined abiotic and biotic stress through the dissection of physiological and molecular crosstalk

    Directory of Open Access Journals (Sweden)

    Christos eKissoudis

    2014-05-01

    Full Text Available Plants growing in their natural habitats are often challenged simultaneously by multiple stress factors, both abiotic and biotic. Research has so far been limited to responses to individual stresses, and understanding of adaptation to combinatorial stress is limited, but indicative of non-additive interactions. Omics data analysis and functional characterization of individual genes has revealed a convergence of signalling pathways for abiotic and biotic stress adaptation. Taking into account that most data originate from imposition of individual stress factors, this review summarizes these findings in a physiological context, following the pathogenesis timeline and highlighting potential differential interactions occurring between abiotic and biotic stress signalling across the different cellular compartments and at the whole plant level. Potential effects of abiotic stress on resistance components such as extracellular receptor proteins, R-genes and systemic acquired resistance will be elaborated, as well as crosstalk at the levels of hormone, ROS and redox signalling. Breeding targets and strategies are proposed focusing on either manipulation and deployment of individual common regulators such as transcription factors or pyramiding of non- (negatively interacting components such as R-genes with abiotic stress resistance genes. We propose that dissection of broad spectrum stress tolerance conferred by priming chemicals may provide an insight on stress cross regulation and additional candidate genes for improving crop performance under combined stress. Validation of the proposed strategies in lab and field experiments is a first step towards the goal of achieving tolerance to combinatorial stress in crops.

  16. Enhancing crop resilience to combined abiotic and biotic stress through the dissection of physiological and molecular crosstalk

    NARCIS (Netherlands)

    Kissoudis, C.; Wiel, van de C.C.M.; Visser, R.G.F.; Linden, van der C.G.

    2014-01-01

    Plants growing in their natural habitats are often challenged simultaneously by multiple stress factors, both abiotic and biotic. Research has so far been limited to responses to individual stresses, and understanding of adaptation to combinatorial stress is limited, but indicative of non-additive i

  17. 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

    2016-08-01

    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. PMID:27296141

  18. 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

    2016-08-01

    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.

  19. A Central Role for Thiols in Plant Tolerance to Abiotic Stress

    Directory of Open Access Journals (Sweden)

    Lyuben Zagorchev

    2013-04-01

    Full Text Available Abiotic stress poses major problems to agriculture and increasing efforts are being made to understand plant stress response and tolerance mechanisms and to develop new tools that underpin successful agriculture. However, the molecular mechanisms of plant stress tolerance are not fully understood, and the data available is incomplete and sometimes contradictory. Here, we review the significance of protein and non-protein thiol compounds in relation to plant tolerance of abiotic stress. First, the roles of the amino acids cysteine and methionine, are discussed, followed by an extensive discussion of the low-molecular-weight tripeptide, thiol glutathione, which plays a central part in plant stress response and oxidative signalling and of glutathione-related enzymes, including those involved in the biosynthesis of non-protein thiol compounds. Special attention is given to the glutathione redox state, to phytochelatins and to the role of glutathione in the regulation of the cell cycle. The protein thiol section focuses on glutaredoxins and thioredoxins, proteins with oxidoreductase activity, which are involved in protein glutathionylation. The review concludes with a brief overview of and future perspectives for the involvement of plant thiols in abiotic stress tolerance.

  20. Stress hormones and abiotic stresses have different effects on antioxidants in maize lines with different sensitivity.

    Science.gov (United States)

    Kellos, T; Tímár, I; Szilágyi, V; Szalai, G; Galiba, G; Kocsy, G

    2008-09-01

    The effect of stress hormones and abiotic stress treatments on reactive oxygen species and on antioxidants was compared in two maize (Zea mays L.) lines (Penjalinan and Z7) having different stress tolerance. Following treatment with abscisic acid, salicylic acid or hydrogen peroxide, the amount of hydrogen peroxide and lipid peroxides increased, while after osmotic stress or cultivation in continuous darkness, the levels were unchanged or decreased. The higher amount of lipid peroxides in Penjalinan indicated its greater sensitivity compared to Z7. The level of the examined antioxidants was increased by nearly all treatments. Glutathione and cysteine contents were higher after salicylic acid, hydrogen peroxide and polyethylene glycol treatments and lower after application of abscisic acid, NaCl and growth in darkness in Z7 than in Penjalinan. The activity of glutathione reductase, ascorbate peroxidase, catalase and glutathione S-transferase was higher after almost all treatments in Z7. The expression of the glutathione synthetase (EC 6.3.2.3) gene was not affected by the treatments, while the level of gamma-glutamylcysteine synthetase (EC 6.3.2.2) and glutathione reductase (EC 1.6.4.2) transcripts increased after most treatments. The two stress hormones and the stress treatments resulted in different changes in antioxidant levels in the two maize lines, which indicates the specific, stress tolerance-dependent response of plants to the various growth regulators and adverse environmental effects that were examined. PMID:18761495

  1. An A20/AN1-zinc-finger domain containing protein gene in tea is differentially expressed during winter dormancy and in response to abiotic stress and plant growth regulators

    Directory of Open Access Journals (Sweden)

    Asosii Paul

    2015-03-01

    Full Text Available The present manuscript describes cloning and expression characterization of A20/AN1-zinc-finger domain containing protein (CsZfp gene in an evergreen tree tea [Camellia sinensis (L. O. Kuntze] in response to winter dormancy (WD, abiotic stresses (polyethylene glycol, hydrogen peroxide, and sodium chloride and plant growth regulators [abscisic acid (ABA, and gibberellic acid (GA3]. CsZfp encoded a putative protein of 173 amino acids with a calculated molecular weight of 18.44 kDa, an isoelectric point (pI of 6.50 and grand average of hydropathicity (GRAVY value of −0.334. The gene did not have an intron, and belonged to a multi-gene family. During the period of active growth (PAG, CsZfp showed maximum expression in root and fruit as compared to leaf, floral bud and stem. Interaction studies between temperature and plant growth regulators on the expression of CsZfp showed that ABA upregulated CsZfp expression at growth temperature (GT; 25 °C but had no effect at low temperature (LT; 4 °C. In response to GA3, upregulation was observed at LT but not at GT. Further, the expression was not modulated by LT either in the tissue harvested during PAG or during WD. It was interesting to record that the expression of CsZfp was upregulated by hydrogen peroxide and sodium chloride, whereas it was non-responsive to polyethylene glycol. The possible role of CsZfp in playing key but differential roles in tea to various abiotic stresses is discussed.

  2. Overexpression of Arabidopsis AnnAt8 Alleviates Abiotic Stress in Transgenic Arabidopsis and Tobacco

    Science.gov (United States)

    Yadav, Deepanker; Ahmed, Israr; Shukla, Pawan; Boyidi, Prasanna; Kirti, Pulugurtha Bharadwaja

    2016-01-01

    Abiotic stress results in massive loss of crop productivity throughout the world. Because of our limited knowledge of the plant defense mechanisms, it is very difficult to exploit the plant genetic resources for manipulation of traits that could benefit multiple stress tolerance in plants. To achieve this, we need a deeper understanding of the plant gene regulatory mechanisms involved in stress responses. Understanding the roles of different members of plant gene families involved in different stress responses, would be a step in this direction. Arabidopsis, which served as a model system for the plant research, is also the most suitable system for the functional characterization of plant gene families. Annexin family in Arabidopsis also is one gene family which has not been fully explored. Eight annexin genes have been reported in the genome of Arabidopsis thaliana. Expression studies of different Arabidopsis annexins revealed their differential regulation under various abiotic stress conditions. AnnAt8 (At5g12380), a member of this family has been shown to exhibit ~433 and ~175 fold increase in transcript levels under NaCl and dehydration stress respectively. To characterize Annexin8 (AnnAt8) further, we have generated transgenic Arabidopsis and tobacco plants constitutively expressing AnnAt8, which were evaluated under different abiotic stress conditions. AnnAt8 overexpressing transgenic plants exhibited higher seed germination rates, better plant growth, and higher chlorophyll retention when compared to wild type plants under abiotic stress treatments. Under stress conditions transgenic plants showed comparatively higher levels of proline and lower levels of malondialdehyde compared to the wild-type plants. Real-Time PCR analyses revealed that the expression of several stress-regulated genes was altered in AnnAt8 over-expressing transgenic tobacco plants, and the enhanced tolerance exhibited by the transgenic plants can be correlated with altered expressions of

  3. Metabolomics as a Tool to Investigate Abiotic Stress Tolerance in Plants

    Directory of Open Access Journals (Sweden)

    Aurelio Gómez-Cadenas

    2013-03-01

    Full Text Available Metabolites reflect the integration of gene expression, protein interaction and other different regulatory processes and are therefore closer to the phenotype than mRNA transcripts or proteins alone. Amongst all –omics technologies, metabolomics is the most transversal and can be applied to different organisms with little or no modifications. It has been successfully applied to the study of molecular phenotypes of plants in response to abiotic stress in order to find particular patterns associated to stress tolerance. These studies have highlighted the essential involvement of primary metabolites: sugars, amino acids and Krebs cycle intermediates as direct markers of photosynthetic dysfunction as well as effectors of osmotic readjustment. On the contrary, secondary metabolites are more specific of genera and species and respond to particular stress conditions as antioxidants, Reactive Oxygen Species (ROS scavengers, coenzymes, UV and excess radiation screen and also as regulatory molecules. In addition, the induction of secondary metabolites by several abiotic stress conditions could also be an effective mechanism of cross-protection against biotic threats, providing a link between abiotic and biotic stress responses. Moreover, the presence/absence and relative accumulation of certain metabolites along with gene expression data provides accurate markers (mQTL or MWAS for tolerant crop selection in breeding programs.

  4. Rubisco Activase Is Also a Multiple Responder to Abiotic Stresses in Rice.

    Directory of Open Access Journals (Sweden)

    Yue Chen

    Full Text Available Ribulose-1,5-bisphosphate carboxylase/oxygenase activase (RCA is a nuclear gene that encodes a chloroplast protein that plays an important role in photosynthesis. Some reports have indicated that it may play a role in acclimation to different abiotic stresses. In this paper, we analyzed the stress-responsive elements in the 2.0 kb 5'-upstream regions of the RCA gene promoter and the primary, secondary and tertiary structure of the protein. We identified some cis-elements of multiple stress-related components in the RCA promoter. Amino acid and evolution analyses showed that the RCA protein had conserved regions between different species; however, the size and type varied. The secondary structures, binding sites and tertiary structures of the RCA proteins were also different. This might reflect the differences in the transcription and translation levels of the two RCA isoforms during adaptation to different abiotic stresses. Although both the transcription and translation levels of RCA isoforms in the rice leaves increased under various stresses, the large isoform was increased more significantly in the chloroplast stroma and thylakoid. It can be concluded that RCA, especially RCAL, is also a multiple responder to abiotic stresses in rice, which provides new insights into RCA functions.

  5. Transcriptional Regulation of Expression of the Maize Aldehyde Dehydrogenase 7 Gene (ZmALDH7B6) in Response to Abiotic Stresses

    Institute of Scientific and Technical Information of China (English)

    GU Ri-liang

    2014-01-01

    Aldehyde dehydrogenases (ALDHs) represent a large protein family, which includes several members that catalyze the oxidation of an aldehyde to its corresponding carboxylic acid in plants. Genes encoding members of theALDH7 subfamily have been suggested to play important roles in various stress adaptations in plants. In this study, quantitative RT-PCR analysis revealed that a maizeALDH7 subfamily member (ZmALDH7B6) was constitutively expressed in various organs, including roots, leaves, immature ears, tassels, and developing seeds. The abundance ofZmALDH7B6 mRNA transcripts in maize roots was increased by ammonium, NaCl, and mannitol treatments. To further analyze tissue-speciifc and stress-induced expression patterns, the 1.5-kb 5´-lfankingZmALDH7B6 promoter region was fused to the β-glucuronidase (GUS) reporter gene and introduced into maize plants. In roots of independent transgenic lines, there was signiifcant induction of GUS activity in response to ammonium supply, conifrming ammonium-dependent expression ofZmALDH7B6 at the transcript level. Histochemical staining showed that GUS activity driven by theZmALDH7B6 promoter was mainly localized in the vascular tissues of maize roots. These results suggested thatZmALDH7B6 is induced by multiple environmental stresses in maize roots, and may play a role in detoxifying aldehydes, particularly in vascular tissue.

  6. The Miscanthus NAC transcription factor MlNAC9 enhances abiotic stress tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Zhao, Xun; Yang, Xuanwen; Pei, Shengqiang; He, Guo; Wang, Xiaoyu; Tang, Qi; Jia, Chunlin; Lu, Ying; Hu, Ruibo; Zhou, Gongke

    2016-07-15

    NAC (NAM, ATAF1/2, and CUC2) transcription factors are known to play important roles in responses to abiotic stresses in plants. Currently, little information regarding the functional roles of NAC genes in stress tolerance is available in Miscanthus lutarioriparius, a promising bioenergy plant for cellulosic ethanol production. In this study, we carried out the functional characterization of MlNAC9 in abiotic stresses. MlNAC9 was shown to act as a nuclear localized transcription activator with the activation domain in its C-terminus. The overexpression of MlNAC9 in Arabidopsis conferred hypersensitivity to abscisic acid (ABA) at seed germination and root elongation stages. In addition, the overexpression of MlNAC9 led to increased seed germination rate and root growth under salt (NaCl) treatment. Meanwhile, the transgenic Arabidopsis overexpressing MlNAC9 showed enhanced tolerance to drought and cold stresses. The expression of stress-responsive marker genes was significantly increased in MlNAC9 overexpression lines compared to that of WT under ABA, drought, salt, and cold stresses. Correspondingly, the activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased and the malondialdehyde (MDA) content was lower accumulated in MlNAC9 overexpression lines under drought and salt treatments. These results indicated that the overexpression of MlNAC9 improved the tolerance to abiotic stresses via an ABA-dependent pathway, and the enhanced tolerance of transgenic plants was mainly attributed to the increased expression of stress-responsive genes and the enhanced scavenging capability of reactive oxygen species (ROS). PMID:27085481

  7. Wheat breeding in abiotic stress conditions of solonetz

    Directory of Open Access Journals (Sweden)

    Dimitrijević Miodrag

    2012-01-01

    Full Text Available The complex stress environment at locality Kumane (Banat primarily is caused by alkaline soil of solonetz type, but includes the other sources of wheat variability, water-logging and occasional extreme temperatures, as well. In order to obtain wheat varieties that could fulfill the requirement of enhanced tolerance to abiotic stress conditions of alkaline soil a set of wheat varieties was examined in parallel trials in Kumane (solonetz, and at Rimski Šančevi on chernzem (black soil. The multiyear results helped to select usable wheat genetic material among the existing varietal genetic variability. That variability was used as parents in in situ established crosses. The results in segregating F2 offspring surpassed the average parental values for examined traits - plant height, grain number and grain weight per spike. Hence, selecting desirable genetic variability in novel variability through years could lead to wheat plant ideotype capable to bring forth a economically justified yield.

  8. Abiotic stress tolerance and competition-related traits underlie phylogenetic clustering in soil bacterial communities.

    Science.gov (United States)

    Goberna, Marta; Navarro-Cano, Jose A; Valiente-Banuet, Alfonso; García, Carlos; Verdú, Miguel

    2014-10-01

    Soil bacteria typically coexist with close relatives generating widespread phylogenetic clustering. This has been ascribed to the abiotic filtering of organisms with shared ecological tolerances. Recent theoretical developments suggest that competition can also explain the phylogenetic similarity of coexisting organisms by excluding large low-competitive clades. We propose that combining the environmental patterns of traits associated with abiotic stress tolerances or competitive abilities with phylogeny and abundance data, can help discern between abiotic and biotic mechanisms underlying the coexistence of phylogenetically related bacteria. We applied this framework in a model system composed of interspersed habitats of highly contrasted productivity and comparatively dominated by biotic and abiotic processes, i.e. the plant patch-gap mosaic typical of drylands. We examined the distribution of 15 traits and 3290 bacterial taxa in 28 plots. Communities showed a marked functional response to the environment. Conserved traits related to environmental stress tolerance (e.g. desiccation, formation of resistant structures) were differentially selected in either habitat, while competition related traits (e.g. organic C consumption, formation of nutrient-scavenging structures) prevailed under high resource availability. Phylogenetic clustering was stronger in habitats dominated by biotic filtering, suggesting that competitive exclusion of large clades might underlie the ecological similarity of co-occurring soil bacteria.

  9. Abiotic Stresses Downregulate Key Genes Involved in Nitrogen Uptake and Assimilation in Brassica juncea L.

    Directory of Open Access Journals (Sweden)

    Parul Goel

    Full Text Available Abiotic stresses such as salinity, drought and extreme temperatures affect nitrogen (N uptake and assimilation in plants. However, little is known about the regulation of N pathway genes at transcriptional level under abiotic stress conditions in Brassica juncea. In the present work, genes encoding nitrate transporters (NRT, ammonium transporters (AMT, nitrate reductase (NR, nitrite reductase (NiR, glutamine synthetase (GS, glutamate synthase (GOGAT, glutamate dehydrogenase (GDH, asparagines synthetase (ASN were cloned from Brassica juncea L. var. Varuna. The deduced protein sequences were analyzed to predict their subcellular localization, which confirmed localization of all the proteins in their respective cellular organelles. The protein sequences were also subjected to conserved domain identification, which confirmed presence of characteristic domains in all the proteins, indicating their putative functions. Moreover, expression of these genes was studied after 1h and 24h of salt (150 mM NaCl, osmotic (250 mM Mannitol, cold (4°C and heat (42°C stresses. Most of the genes encoding nitrate transporters and enzymes responsible for N assimilation and remobilization were found to be downregulated under abiotic stresses. The expression of BjAMT1.2, BjAMT2, BjGS1.1, BjGDH1 and BjASN2 was downregulated after 1hr, while expression of BjNRT1.1, BjNRT2.1, BjNiR1, BjAMT2, BjGDH1 and BjASN2 was downregulated after 24h of all the stress treatments. However, expression of BjNRT1.1, BjNRT1.5 and BjGDH2 was upregulated after 1h of all stress treatments, while no gene was found to be upregulated after 24h of stress treatments, commonly. These observations indicate that expression of most of the genes is adversely affected under abiotic stress conditions, particularly under prolonged stress exposure (24h, which may be one of the reasons of reduction in plant growth and development under abiotic stresses.

  10. Abiotic Stresses Downregulate Key Genes Involved in Nitrogen Uptake and Assimilation in Brassica juncea L.

    Science.gov (United States)

    Goel, Parul; Singh, Anil Kumar

    2015-01-01

    Abiotic stresses such as salinity, drought and extreme temperatures affect nitrogen (N) uptake and assimilation in plants. However, little is known about the regulation of N pathway genes at transcriptional level under abiotic stress conditions in Brassica juncea. In the present work, genes encoding nitrate transporters (NRT), ammonium transporters (AMT), nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), glutamate synthase (GOGAT), glutamate dehydrogenase (GDH), asparagines synthetase (ASN) were cloned from Brassica juncea L. var. Varuna. The deduced protein sequences were analyzed to predict their subcellular localization, which confirmed localization of all the proteins in their respective cellular organelles. The protein sequences were also subjected to conserved domain identification, which confirmed presence of characteristic domains in all the proteins, indicating their putative functions. Moreover, expression of these genes was studied after 1h and 24h of salt (150 mM NaCl), osmotic (250 mM Mannitol), cold (4°C) and heat (42°C) stresses. Most of the genes encoding nitrate transporters and enzymes responsible for N assimilation and remobilization were found to be downregulated under abiotic stresses. The expression of BjAMT1.2, BjAMT2, BjGS1.1, BjGDH1 and BjASN2 was downregulated after 1hr, while expression of BjNRT1.1, BjNRT2.1, BjNiR1, BjAMT2, BjGDH1 and BjASN2 was downregulated after 24h of all the stress treatments. However, expression of BjNRT1.1, BjNRT1.5 and BjGDH2 was upregulated after 1h of all stress treatments, while no gene was found to be upregulated after 24h of stress treatments, commonly. These observations indicate that expression of most of the genes is adversely affected under abiotic stress conditions, particularly under prolonged stress exposure (24h), which may be one of the reasons of reduction in plant growth and development under abiotic stresses. PMID:26605918

  11. Promoter Analysis and Transcriptional Profiling of Ginkgo biloba 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase (GbHMGR gene in Abiotic Stress Responses

    Directory of Open Access Journals (Sweden)

    Yongling LIAO

    2015-04-01

    Full Text Available The terpene trilactones (TTLs are believed to be important for the pharmacological properties of Ginkgo biloba leaves extract. 3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGR is a critical enzyme involved in the biosynthetic pathway of TTLs. In this study, an 1.2-kb fragment of 5’ flanking region of the HMGR gene (GbHMGR, was isolated from G. biloba by genome walking. Extensive sequence analysis revealed the presence of evolutionarily conserved and over-represented putative cis-acting elements in light-regulated transcription,  hormone signaling (gibberellic acid, jasmonate and salicylic acid, elicitor and stress responses (cold/dehydration responses, and plant defense signaling (W-box/WRKY that are common to the promoter region of GbHMGR. EMSA analysis suggested possible functionality of W-box in GbHMGR promoter region. The behavior of gene transcripts in ginkgo callus upon light, low temperature, MeJA and SA treatments further verified the regulatory function of GbHMGR promoter. A significant positive relationship between gene expression level and total TTL contents suggested that GbHMGR might be one of key genes involved in TTL biosynthesis in G. biloba.

  12. Identification of the dehydrin gene family from grapevine species and analysis of their responsiveness to various forms of abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Yang Yazhou

    2012-08-01

    Full Text Available Abstract Background Dehydrins (DHNs protect plant cells from desiccation damage during environmental stress, and also participate in host resistance to various pathogens. In this study, we aimed to identify and characterize the DHN gene families from Vitis vinifera and wild V. yeshanensis, which is tolerant to both drought and cold, and moderately resistant to powdery mildew. Results Four DHN genes were identified in both V. vinifera and V. yeshanensis, which shared a high sequence identity between the two species but little homology between the genes themselves. These genes were designated DHN1, DHN2, DHN3 and DHN4. All four of the DHN proteins were highly hydrophilic and were predicted to be intrinsically disordered, but they differed in their isoelectric points, kinase selectivities and number of functional motifs. Also, the expression profiles of each gene differed appreciably from one another. Grapevine DHN1 was not expressed in vegetative tissues under normal growth conditions, but was induced by drought, cold, heat, embryogenesis, as well as the application of abscisic acid (ABA, salicylic acid (SA, and methyl jasmonate (MeJA. It was expressed earlier in V. yeshanensis under drought conditions than in V. vinifera, and also exhibited a second round of up-regulation in V. yeshanensis following inoculation with Erysiphe necator, which was not apparent in V. vinifera. Like DHN1, DHN2 was induced by cold, heat, embryogenesis and ABA; however, it exhibited no responsiveness to drought, E. necator infection, SA or MeJA, and was also expressed constitutively in vegetative tissues under normal growth conditions. Conversely, DHN3 was only expressed during seed development at extremely low levels, and DHN4 was expressed specifically during late embryogenesis. Neither DHN3 nor DHN4 exhibited responsiveness to any of the treatments carried out in this study. Interestingly, the presence of particular cis-elements within the promoter regions of each

  13. Impacts of biotic and abiotic stress on major quality attributing metabolites of coffee beans.

    Science.gov (United States)

    Vaddadi, Sridevi; Parvatam, Giridhar

    2015-03-01

    Biotic stress factors such as Rhizopus oligosporus and Aspergillus niger mycelial extracts and abiotic elements methyljasmonate (MJ) and salicylic acid (SA), when administered through floral spray to Coffea canephora, showed significant influence on major bioactive metabolites of beans. Up to 42% caffeine, 39% theobromine and 46% trigonelline, along with 32% cafestol and kahweol content elevation was evident under respective elicitor treatments. Over all, the surge in respective metabolites depends on elicitor stress type and concentration. Abiotic factors MJ and SA were found to be efficient at 1 to 5 microM concentration in augmenting all the metabolites, compared to R. oligosporus and A. niger spray at 0.5-2.0% wherein the response was moderate as compared to abiotic stress, however significant compared to control. Though this elevation in caffeine, theobromine, cafestol and kahweol is not warranted from quality point of view, increase in trigonelline improves coffee quality. Besides increase in metabolites, stress mediated augmentation of bioactive compounds in coffee has a wide scope for studying gene expression pattern. PMID:25895259

  14. Genome-wide identification and characterization of the apple (Malus domestica) HECT ubiquitin-protein ligase family and expression analysis of their responsiveness to abiotic stresses.

    Science.gov (United States)

    Xu, Jianing; Xing, Shanshan; Cui, Haoran; Chen, Xuesen; Wang, Xiaoyun

    2016-04-01

    The ubiquitin-protein ligases (E3s) directly participate in ubiquitin (Ub) transferring to the target proteins in the ubiquitination pathway. The HECT ubiquitin-protein ligase (UPL), one type of E3s, is characterized as containing a conserved HECT domain of approximately 350 amino acids in the C terminus. Some UPLs were found to be involved in trichome development and leaf senescence in Arabidopsis. However, studies on plant UPLs, such as characteristics of the protein structure, predicted functional motifs of the HECT domain, and the regulatory expression of UPLs have all been limited. Here, we present genome-wide identification of the genes encoding UPLs (HECT gene) in apple. The 13 genes (named as MdUPL1-MdUPL13) from ten different chromosomes were divided into four groups by phylogenetic analysis. Among these groups, the encoding genes in the intron-exon structure and the included additional functional domains were quite different. Notably, the F-box domain was first found in MdUPL7 in plant UPLs. The HECT domain in different MdUPL groups also presented different spatial features and three types of conservative motifs were identified. The promoters of each MdUPL member carried multiple stress-response related elements by cis-acting element analysis. Experimental results demonstrated that the expressions of several MdUPLs were quite sensitive to cold-, drought-, and salt-stresses by qRT-PCR assay. The results of this study helped to elucidate the functions of HECT proteins, especially in Rosaceae plants.

  15. Alfalfa Cellulose synthase gene expression under abiotic stress: a Hitchhiker's guide to RT-qPCR normalization.

    Directory of Open Access Journals (Sweden)

    Gea Guerriero

    Full Text Available Abiotic stress represents a serious threat affecting both plant fitness and productivity. One of the promptest responses that plants trigger following abiotic stress is the differential expression of key genes, which enable to face the adverse conditions. It is accepted and shown that the cell wall senses and broadcasts the stress signal to the interior of the cell, by triggering a cascade of reactions leading to resistance. Therefore the study of wall-related genes is particularly relevant to understand the metabolic remodeling triggered by plants in response to exogenous stresses. Despite the agricultural and economical relevance of alfalfa (Medicago sativa L., no study, to our knowledge, has addressed specifically the wall-related gene expression changes in response to exogenous stresses in this important crop, by monitoring the dynamics of wall biosynthetic gene expression. We here identify and analyze the expression profiles of nine cellulose synthases, together with other wall-related genes, in stems of alfalfa plants subjected to different abiotic stresses (cold, heat, salt stress at various time points (e.g. 0, 24, 72 and 96 h. We identify 2 main responses for specific groups of genes, i.e. a salt/heat-induced and a cold/heat-repressed group of genes. Prior to this analysis we identified appropriate reference genes for expression analyses in alfalfa, by evaluating the stability of 10 candidates across different tissues (namely leaves, stems, roots, under the different abiotic stresses and time points chosen. The results obtained confirm an active role played by the cell wall in response to exogenous stimuli and constitute a step forward in delineating the complex pathways regulating the response of plants to abiotic stresses.

  16. Cullin-RING Ubiquitin Ligase Family in Plant Abiotic Stress Pathways

    Institute of Scientific and Technical Information of China (English)

    Liquan Guo; Cynthia D.Nezames; Lianxi Sheng; Xingwang Deng; Ning Wei

    2013-01-01

    The ubiquitin-proteasome system is a key mechanism that plants use to generate adaptive responses in coping with various environmental stresses.Cullin-RING (CRL) complexes represent a predominant group of ubiquitin E3 ligases in this system.In this review,we focus on the CRL E3s that have been implicated in abiotic stress signaling pathways in Arabidopsis.By comparing and analyzing these cases,we hope to gain a better understanding on how CRL complexes work under various settings in an attempt to decipher the clues about the regulatory mechanism of CRL E3s.

  17. Exogenous application of hydrogen sulfide donor sodium hydrosulfide enhanced multiple abiotic stress tolerance in bermudagrass (Cynodon dactylon (L). Pers.).

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Chan, Zhulong

    2013-10-01

    As a gaseous molecule, hydrogen sulfide (H2S) has been recently found to be involved in plant responses to multiple abiotic stress. In this study, salt (150 and 300 mM NaCl), osmotic (15% and 30% PEG6000) and cold (4 °C) stress treatments induced accumulation of endogenous H2S level, indicating that H2S might play a role in bermudagrass responses to salt, osmotic and cold stresses. Exogenous application of H2S donor (sodium hydrosulfide, NaHS) conferred improved salt, osmotic and freezing stress tolerances in bermudagrass, which were evidenced by decreased electrolyte leakage and increased survival rate under stress conditions. Additionally, NaHS treatment alleviated the reactive oxygen species (ROS) burst and cell damage induced by abiotic stress, via modulating metabolisms of several antioxidant enzymes [catalase (CAT), peroxidase (POD) and GR (glutathione reductase)] and non-enzymatic glutathione antioxidant pool and redox state. Moreover, exogenous NaHS treatment led to accumulation of osmolytes (proline, sucrose and soluble total sugars) in stressed bermudagrass plants. Taken together, all these data indicated the protective roles of H2S in bermudagrass responses to salt, osmotic and freezing stresses, via activation of the antioxidant response and osmolyte accumulation. These findings might be applicable to grass and crop engineering to improve abiotic stress tolerance.

  18. Late Embryogenesis Abundant (LEA Constitutes a Large and Diverse Family of Proteins Involved in Development and Abiotic Stress Responses in Sweet Orange (Citrus sinensis L. Osb..

    Directory of Open Access Journals (Sweden)

    Andresa Muniz Pedrosa

    Full Text Available Late Embryogenesis Abundant (LEA proteins are an ubiquitous group of polypeptides that were first described to accumulate during plant seed dehydration, at the later stages of embryogenesis. Since then they have also been recorded in vegetative plant tissues experiencing water limitation and in anhydrobiotic bacteria and invertebrates and, thereby, correlated with the acquisition of desiccation tolerance. This study provides the first comprehensive study about the LEA gene family in sweet orange (Citrus sinensis L. Osb., the most important and widely grown fruit crop around the world. A surprisingly high number (72 of genes encoding C. sinensis LEAs (CsLEAs were identified and classified into seven groups (LEA_1, LEA_2, LEA_3 and LEA_4, LEA_5, DEHYDRIN and SMP based on their predicted amino acid sequences and also on their phylogenetic relationships with the complete set of Arabidopsis thaliana LEA proteins (AtLEAs. Approximately 60% of the CsLEAs identified in this study belongs to the unusual LEA_2 group of more hydrophobic LEA proteins, while the other LEA groups contained a relatively small number of members typically hydrophilic. A correlation between gene structure and motif composition was observed within each LEA group. Investigation of their chromosomal localizations revealed that the CsLEAs were non-randomly distributed across all nine chromosomes and that 33% of all CsLEAs are segmentally or tandemly duplicated genes. Analysis of the upstream sequences required for transcription revealed the presence of various stress-responsive cis-acting regulatory elements in the promoter regions of CsLEAs, including ABRE, DRE/CRT, MYBS and LTRE. Expression analysis using both RNA-seq data and quantitative real-time RT-PCR (qPCR revealed that the CsLEA genes are widely expressed in various tissues, and that many genes containing the ABRE promoter sequence are induced by drought, salt and PEG. These results provide a useful reference for further

  19. Late Embryogenesis Abundant (LEA) Constitutes a Large and Diverse Family of Proteins Involved in Development and Abiotic Stress Responses in Sweet Orange (Citrus sinensis L. Osb.).

    Science.gov (United States)

    Pedrosa, Andresa Muniz; Martins, Cristina de Paula Santos; Gonçalves, Luana Pereira; Costa, Marcio Gilberto Cardoso

    2015-01-01

    Late Embryogenesis Abundant (LEA) proteins are an ubiquitous group of polypeptides that were first described to accumulate during plant seed dehydration, at the later stages of embryogenesis. Since then they have also been recorded in vegetative plant tissues experiencing water limitation and in anhydrobiotic bacteria and invertebrates and, thereby, correlated with the acquisition of desiccation tolerance. This study provides the first comprehensive study about the LEA gene family in sweet orange (Citrus sinensis L. Osb.), the most important and widely grown fruit crop around the world. A surprisingly high number (72) of genes encoding C. sinensis LEAs (CsLEAs) were identified and classified into seven groups (LEA_1, LEA_2, LEA_3 and LEA_4, LEA_5, DEHYDRIN and SMP) based on their predicted amino acid sequences and also on their phylogenetic relationships with the complete set of Arabidopsis thaliana LEA proteins (AtLEAs). Approximately 60% of the CsLEAs identified in this study belongs to the unusual LEA_2 group of more hydrophobic LEA proteins, while the other LEA groups contained a relatively small number of members typically hydrophilic. A correlation between gene structure and motif composition was observed within each LEA group. Investigation of their chromosomal localizations revealed that the CsLEAs were non-randomly distributed across all nine chromosomes and that 33% of all CsLEAs are segmentally or tandemly duplicated genes. Analysis of the upstream sequences required for transcription revealed the presence of various stress-responsive cis-acting regulatory elements in the promoter regions of CsLEAs, including ABRE, DRE/CRT, MYBS and LTRE. Expression analysis using both RNA-seq data and quantitative real-time RT-PCR (qPCR) revealed that the CsLEA genes are widely expressed in various tissues, and that many genes containing the ABRE promoter sequence are induced by drought, salt and PEG. These results provide a useful reference for further exploration of

  20. Field evaluation of durum wheat landraces for prevailing abiotic and biotic stresses in highland rainfed regions of Iran

    Institute of Scientific and Technical Information of China (English)

    Reza Mohammadi; Behzad Sadeghzadeh; Hasan Ahmadi; Nowzar Bahrami; Ahmed Amri

    2015-01-01

    Biotic and abiotic stresses are major limiting factors for high crop productivity worldwide. A landrace collection consisting of 380 durum wheat (Triticum turgidum L. var. durum) entries originating in several countries along with four check varieties were evaluated for biotic stresses:yellow rust (Puccinia stri formis Westendorf f. sp. tritici) and wheat stem sawfly (WSS) Cephus cinctus Norton (Hymenoptera:Cephidae), and abiotic stresses:cold and drought. The main objectives were to (i) quantify phenotypic diversity and identify variation in the durum wheat landraces for the different stresses and (ii) characterize the agronomic profiles of landraces in reaction to the stresses. Significant changes in reactions of landraces to stresses were observed. Landraces resistant to each stress were identified and agronomically characterized. Percentage reduction due to the stresses varied from 11.4% (yellow rust) to 21.6% (cold stress) for 1000-kernel weight (TKW) and from 19.9 (yellow rust) to 91.9%(cold stress) for grain yield. Landraces from Asia and Europe showed enhanced genetic potential for both grain yield and cold tolerance under highland rainfed conditions of Iran. The findings showed that TKW and yield productivity could be used to assess the response of durum wheat landraces to different stresses. In conclusion, landraces showed high levels of resistance to both biotic and abiotic stresses, and selected landraces can serve in durum wheat breeding for adaptation to cold and drought-prone environments.

  1. Field evaluation of durum wheat landraces for prevailing abiotic and biotic stresses in highland rainfed regions of Iran

    Institute of Scientific and Technical Information of China (English)

    Reza; Mohammadi; Behzad; Sadeghzadeh; Hasan; Ahmadi; Nowzar; Bahrami; Ahmed; Amri

    2015-01-01

    Biotic and abiotic stresses are major limiting factors for high crop productivity worldwide. A landrace collection consisting of 380 durum wheat(Triticum turgidum L. var. durum) entries originating in several countries along with four check varieties were evaluated for biotic stresses:yellow rust(Puccinia striiformis Westendorf f. sp. tritici) and wheat stem sawfly(WSS) Cephus cinctus Norton(Hymenoptera: Cephidae), and abiotic stresses: cold and drought. The main objectives were to(i) quantify phenotypic diversity and identify variation in the durum wheat landraces for the different stresses and(ii) characterize the agronomic profiles of landraces in reaction to the stresses. Significant changes in reactions of landraces to stresses were observed.Landraces resistant to each stress were identified and agronomically characterized.Percentage reduction due to the stresses varied from 11.4%(yellow rust) to 21.6%(cold stress) for 1000-kernel weight(TKW) and from 19.9(yellow rust) to 91.9%(cold stress) for grain yield. Landraces from Asia and Europe showed enhanced genetic potential for both grain yield and cold tolerance under highland rainfed conditions of Iran. The findings showed that TKW and yield productivity could be used to assess the response of durum wheat landraces to different stresses. In conclusion, landraces showed high levels of resistance to both biotic and abiotic stresses, and selected landraces can serve in durum wheat breeding for adaptation to cold and drought-prone environments.

  2. Multiple Reaction Monitoring Mode Based Liquid Chromatography-Mass Spectrometry Method for Simultaneous Quantification of Brassinolide and Other Plant Hormones Involved in Abiotic Stresses

    OpenAIRE

    Deepak M. Kasote; Ritesh Ghosh; Jun Young Chung; Jonggeun Kim; Inhwan Bae; Hanhong Bae

    2016-01-01

    Plant hormones are the key regulators of adaptive stress response. Abiotic stresses such as drought and salt are known to affect the growth and productivity of plants. It is well known that the levels of plant hormones such as zeatin (ZA), abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and brassinolide (BR) fluctuate upon abiotic stress exposure. At present, there is not any single suitable liquid chromatography-mass spectrometry (LC-MS) method for simultaneous analysis of BR a...

  3. Phytohormones and their metabolic engineering for abiotic stress tolerance in crop plants

    Institute of Scientific and Technical Information of China (English)

    Shabir H. Wani; Vinay Kumar; Varsha Shriram; Saroj Kumar Sah

    2016-01-01

    Abiotic stresses including drought, salinity, heat, cold, flooding, and ultraviolet radiation causes crop losses worldwide. In recent times, preventing these crop losses and producing more food and feed to meet the demands of ever-increasing human populations have gained unprecedented importance. However, the proportion of agricultural lands facing multiple abiotic stresses is expected only to rise under a changing global climate fueled by anthropogenic activities. Identifying the mechanisms developed and deployed by plants to counteract abiotic stresses and maintain their growth and survival under harsh conditions thus holds great significance. Recent investigations have shown that phytohormones, including the classical auxins, cytokinins, ethylene, and gibberellins, and newer members including brassinosteroids, jasmonates, and strigolactones may prove to be important metabolic engineering targets for producing abiotic stress-tolerant crop plants. In this review, we summarize and critically assess the roles that phytohormones play in plant growth and development and abiotic stress tolerance, besides their engineering for conferring abiotic stress tolerance in transgenic crops. We also describe recent successes in identifying the roles of phytohormones under stressful conditions. We conclude by describing the recent progress and future prospects including limitations and challenges of phytohormone engineering for inducing abiotic stress tolerance in crop plants.

  4. Phytohormones and their metabolic engineering for abiotic stress tolerance in crop plants

    Directory of Open Access Journals (Sweden)

    Shabir H. Wani

    2016-06-01

    Full Text Available Abiotic stresses including drought, salinity, heat, cold, flooding, and ultraviolet radiation causes crop losses worldwide. In recent times, preventing these crop losses and producing more food and feed to meet the demands of ever-increasing human populations have gained unprecedented importance. However, the proportion of agricultural lands facing multiple abiotic stresses is expected only to rise under a changing global climate fueled by anthropogenic activities. Identifying the mechanisms developed and deployed by plants to counteract abiotic stresses and maintain their growth and survival under harsh conditions thus holds great significance. Recent investigations have shown that phytohormones, including the classical auxins, cytokinins, ethylene, and gibberellins, and newer members including brassinosteroids, jasmonates, and strigolactones may prove to be important metabolic engineering targets for producing abiotic stress-tolerant crop plants. In this review, we summarize and critically assess the roles that phytohormones play in plant growth and development and abiotic stress tolerance, besides their engineering for conferring abiotic stress tolerance in transgenic crops. We also describe recent successes in identifying the roles of phytohormones under stressful conditions. We conclude by describing the recent progress and future prospects including limitations and challenges of phytohormone engineering for inducing abiotic stress tolerance in crop plants.

  5. Sugar signalling and gene expression in relation to carbohydrate metabolism under abiotic stresses in plants

    Indian Academy of Sciences (India)

    Anil K Gupta; Narinder Kaur

    2005-12-01

    Sucrose is required for plant growth and development. The sugar status of plant cells is sensed by sensor proteins. The signal generated by signal transduction cascades, which could involve mitogen-activated protein kinases, protein phosphatases, Ca2+ and calmodulins, results in appropriate gene expression. A variety of genes are either induced or repressed depending upon the status of soluble sugars. Abiotic stresses to plants result in major alterations in sugar status and hence affect the expression of various genes by down- and up-regulating their expression. Hexokinase-dependent and hexokinase-independent pathways are involved in sugar sensing. Sucrose also acts as a signal molecule as it affects the activity of a proton-sucrose symporter. The sucrose transporter acts as a sucrose sensor and is involved in phloem loading. Fructokinase may represent an additional sensor that bypasses hexokinase phosphorylation especially when sucrose synthase is dominant. Mutants isolated on the basis of response of germination and seedling growth to sugars and reporter-based screening protocols are being used to study the response of altered sugar status on gene expression. Common cis-acting elements in sugar signalling pathways have been identified. Transgenic plants with elevated levels of sugars/sugar alcohols like fructans, raffinose series oligosaccharides, trehalose and mannitol are tolerant to different stresses but have usually impaired growth. Efforts need to be made to have transgenic plants in which abiotic stress responsive genes are expressed only at the time of adverse environmental conditions instead of being constitutively synthesized.

  6. Short leaf mutation and modified plant architecture as potential traits for improving biomass and abiotic stress tolerance in sorghum

    Science.gov (United States)

    The significant contributions of plant architecture to yield and biomass production have been the focus of attention in a number of crop plants. Recently, the relationship between plant architecture, biomass characteristics and responses to abiotic stresses has also been a subject of considerable in...

  7. HvPap-1 C1A protease actively participates in barley proteolysis mediated by abiotic stresses.

    Science.gov (United States)

    Velasco-Arroyo, Blanca; Diaz-Mendoza, Mercedes; Gandullo, Jacinto; Gonzalez-Melendi, Pablo; Santamaria, M Estrella; Dominguez-Figueroa, Jose D; Hensel, Goetz; Martinez, Manuel; Kumlehn, Jochen; Diaz, Isabel

    2016-07-01

    Protein breakdown and mobilization from old or stressed tissues to growing and sink organs are some of the metabolic features associated with abiotic/biotic stresses, essential for nutrient recycling. The massive degradation of proteins implies numerous proteolytic events in which cysteine-proteases are the most abundant key players. Analysing the role of barley C1A proteases in response to abiotic stresses is crucial due to their impact on plant growth and grain yield and quality. In this study, dark and nitrogen starvation treatments were selected to induce stress in barley. Results show that C1A proteases participate in the proteolytic processes triggered in leaves by both abiotic treatments, which strongly induce the expression of the HvPap-1 gene encoding a cathepsin F-like protease. Differences in biochemical parameters and C1A gene expression were found when comparing transgenic barley plants overexpressing or silencing the HvPap-1 gene and wild-type dark-treated leaves. These findings associated with morphological changes evidence a lifespan-delayed phenotype of HvPap-1 silenced lines. All these data elucidate on the role of this protease family in response to abiotic stresses and the potential of their biotechnological manipulation to control the timing of plant growth. PMID:27217548

  8. Expression of a finger millet transcription factor, EcNAC1, in tobacco confers abiotic stress-tolerance.

    Directory of Open Access Journals (Sweden)

    Venkategowda Ramegowda

    Full Text Available NAC (NAM, ATAF1-2, and CUC2 proteins constitute one of the largest families of plant-specific transcription factors and have been shown to be involved in diverse plant processes including plant growth, development, and stress-tolerance. In this study, a stress-responsive NAC gene, EcNAC1, was isolated from the subtracted stress cDNA library generated from a drought adapted crop, finger millet, and characterized for its role in stress-tolerance. The expression analysis showed that EcNAC1 was highly induced during water-deficit and salt stress. EcNAC1 shares high amino acid similarity with rice genes that have been phylogenetically classified into stress-related NAC genes. Our results demonstrated that tobacco transgenic plants expressing EcNAC1 exhibit tolerance to various abiotic stresses like simulated osmotic stress, by polyethylene glycol (PEG and mannitol, and salinity stress. The transgenic plants also showed enhanced tolerance to methyl-viologen (MV induced oxidative stress. Reduced levels of reactive oxygen species (ROS and ROS-induced damage were noticed in pot grown transgenic lines under water-deficit and natural high light conditions. Root growth under stress and recovery growth after stress alleviation was more in transgenic plants. Many stress-responsive genes were found to be up-regulated in transgenic lines expressing EcNAC1. Our results suggest that EcNAC1 overexpression confers tolerance against abiotic stress in susceptible species, tobacco.

  9. Differentially expressed seed aging responsive heat shock protein OsHSP18.2 implicates in seed vigor, longevity and improves germination and seedling establishment under abiotic stress

    OpenAIRE

    Kaur, Harmeet; Petla, Bhanu P.; Kamble, Nitin U.; Singh, Ajeet; Rao, Venkateswara; Salvi, Prafull; Ghosh, Shraboni; Majee, Manoj

    2015-01-01

    Small heat shock proteins (sHSPs) are a diverse group of proteins and are highly abundant in plant species. Although majority of these sHSPs were shown to express specifically in seed, their potential function in seed physiology remains to be fully explored. Our proteomic analysis revealed that OsHSP18.2, a class II cytosolic HSP is an aging responsive protein as its abundance significantly increased after artificial aging in rice seeds. OsHSP18.2 transcript was found to markedly increase at ...

  10. Differentially expressed seed aging responsive heat shock protein OsHSP18.2 implicates in seed vigor, longevity and improves germination and seedling establishment under abiotic stress.

    Directory of Open Access Journals (Sweden)

    Harmeet eKaur

    2015-09-01

    Full Text Available Small heat shock proteins (sHSP are a diverse group of proteins and are highly abundant in plant species. Although majority of these sHSPs were shown to express specifically in seed, their potential function in seed physiology remains to be fully explored. Our proteomic analysis revealed that OsHSP18.2, a class II cytosolic HSP is an aging responsive protein as its abundance significantly increased after artificial aging in rice seeds. OsHSP18.2 transcript was found to markedly increase at the late maturation stage being highly abundant in dry seeds and sharply decreased after germination. Our biochemical study clearly demonstrated that OsHSP18.2 forms homooligomeric complex and is dodecameric in nature and functions as a molecular chaperon. OsHSP18.2 displayed chaperone activity as it was effective in preventing thermal inactivation of Citrate Synthase. Further, to analyze the function of this protein in seed physiology, seed specific Arabidopsis overexpression lines for OsHSP18.2 were generated. Our subsequent functional analysis clearly demonstrated that OsHSP18.2 has ability to improve seed vigor and longevity by reducing deleterious ROS accumulation in seeds. In addition, transformed Arabidopsis seeds displayed better performance in germination and cotyledon emergence under adverse conditions as well. Collectively, our work demonstrates that OsHSP18.2 is an aging responsive protein which functions as a molecular chaperon and possibly protect and stabilize the cellular proteins from irreversible damage particularly during maturation drying, desiccation and aging in seeds by restricting ROS accumulation and thereby improves seed vigor, longevity and seedling establishment.

  11. Differentially expressed seed aging responsive heat shock protein OsHSP18.2 implicates in seed vigor, longevity and improves germination and seedling establishment under abiotic stress.

    Science.gov (United States)

    Kaur, Harmeet; Petla, Bhanu P; Kamble, Nitin U; Singh, Ajeet; Rao, Venkateswara; Salvi, Prafull; Ghosh, Shraboni; Majee, Manoj

    2015-01-01

    Small heat shock proteins (sHSPs) are a diverse group of proteins and are highly abundant in plant species. Although majority of these sHSPs were shown to express specifically in seed, their potential function in seed physiology remains to be fully explored. Our proteomic analysis revealed that OsHSP18.2, a class II cytosolic HSP is an aging responsive protein as its abundance significantly increased after artificial aging in rice seeds. OsHSP18.2 transcript was found to markedly increase at the late maturation stage being highly abundant in dry seeds and sharply decreased after germination. Our biochemical study clearly demonstrated that OsHSP18.2 forms homooligomeric complex and is dodecameric in nature and functions as a molecular chaperone. OsHSP18.2 displayed chaperone activity as it was effective in preventing thermal inactivation of Citrate Synthase. Further, to analyze the function of this protein in seed physiology, seed specific Arabidopsis overexpression lines for OsHSP18.2 were generated. Our subsequent functional analysis clearly demonstrated that OsHSP18.2 has ability to improve seed vigor and longevity by reducing deleterious ROS accumulation in seeds. In addition, transformed Arabidopsis seeds also displayed better performance in germination and cotyledon emergence under adverse conditions. Collectively, our work demonstrates that OsHSP18.2 is an aging responsive protein which functions as a molecular chaperone and possibly protect and stabilize the cellular proteins from irreversible damage particularly during maturation drying, desiccation and aging in seeds by restricting ROS accumulation and thereby improves seed vigor, longevity and seedling establishment. PMID:26442027

  12. The Arabidopsis PLAT domain protein1 is critically involved in abiotic stress tolerance

    DEFF Research Database (Denmark)

    Hyun, Tae Kyung; van der Graaff, Eric; Albacete, Alfonso;

    2014-01-01

    of functional genetic and physiological approaches. PLAT1 overexpression conferred increased abiotic stress tolerance, including cold, drought and salt stress, while loss-of-function resulted in opposite effects on abiotic stress tolerance. Strikingly, PLAT1 promoted growth under non-stressed conditions...... and belong to the PLAT-plant-stress protein family are ubiquitously present in monocot and dicots. However, the function of PLAT-plant-stress proteins is still poorly understood. Therefore, we have assessed the function of the uncharacterised Arabidopsis PLAT-plant-stress family members through a combination....... Abiotic stress treatments induced PLAT1 expression and caused expansion of its expression domain. The ABF/ABRE transcription factors, which are positive mediators of abscisic acid signalling, activate PLAT1 promoter activity in transactivation assays and directly bind to the ABRE elements located...

  13. Multiple abiotic stress tolerance of the transformants yeast cells and the transgenic Arabidopsis plants expressing a novel durum wheat catalase.

    Science.gov (United States)

    Feki, Kaouthar; Kamoun, Yosra; Ben Mahmoud, Rihem; Farhat-Khemakhem, Ameny; Gargouri, Ali; Brini, Faiçal

    2015-12-01

    Catalases are reactive oxygen species scavenging enzymes involved in response to abiotic and biotic stresses. In this study, we described the isolation and functional characterization of a novel catalase from durum wheat, designed TdCAT1. Molecular Phylogeny analyses showed that wheat TdCAT1 exhibited high amino acids sequence identity to other plant catalases. Sequence homology analysis showed that TdCAT1 protein contained the putative calmodulin binding domain and a putative conserved internal peroxisomal targeting signal PTS1 motif around its C-terminus. Predicted three-dimensional structural model revealed the presence of four putative distinct structural regions which are the N-terminal arm, the β-barrel, the wrapping and the α-helical domains. TdCAT1 protein had the heme pocket that was composed by five essential residues. TdCAT1 gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdCAT1 in yeast cells and Arabidopsis plants conferred tolerance to several abiotic stresses. Compared with the non-transformed plants, the transgenic lines maintained their growth and accumulated more proline under stress treatments. Furthermore, the amount of H2O2 was lower in transgenic lines, which was due to the high CAT and POD activities. Taken together, these data provide the evidence for the involvement of durum wheat catalase TdCAT1 in tolerance to multiple abiotic stresses in crop plants. PMID:26555900

  14. Cloning of four DREB genes from Tibetan Sophora moorcroftiana and analysis of their expression during abiotic stress

    Institute of Scientific and Technical Information of China (English)

    Weijie Yao; Yaru Fu; Yanfu Zhang; Hui-e Li

    2016-01-01

    Sophora moorcroftiana is an endemic, drought-resistant shrub that grows in Tibet and has some degree of resistance to salt, cold, heat, and drought. In the present study, four dehydration responsive element-binding (DREB) genes (SmDREB1, SmDREB2, SmDREB and SmDREB1) were isolated from S. moorcroftiana for the first time and their expression and proline content under abiotic stress were analyzed. Proline accumulated in seedlings under drought, salt, cold, and heat stress treat-ments. The four genes were variously expressed in response to the four abiotic stresses. SmDREB1 was induced by drought, cold, and heat stresses;SmDREB2 and SmDREB4 were both induced by salt, cold, and heat stresses, whereas SmDREB3 was induced by drought and heat stresses. Thus, these four genes may participate in conferring tolerance to these four abiotic stresses and are candidate genes for genetic engineering in the future.

  15. Rice phospholipase A superfamily: organization, phylogenetic and expression analysis during abiotic stresses and development.

    Directory of Open Access Journals (Sweden)

    Amarjeet Singh

    Full Text Available BACKGROUND: Phospholipase A (PLA is an important group of enzymes responsible for phospholipid hydrolysis in lipid signaling. PLAs have been implicated in abiotic stress signaling and developmental events in various plants species. Genome-wide analysis of PLA superfamily has been carried out in dicot plant Arabidopsis. A comprehensive genome-wide analysis of PLAs has not been presented yet in crop plant rice. METHODOLOGY/PRINCIPAL FINDINGS: A comprehensive bioinformatics analysis identified a total of 31 PLA encoding genes in the rice genome, which are divided into three classes; phospholipase A(1 (PLA(1, patatin like phospholipases (pPLA and low molecular weight secretory phospholipase A(2 (sPLA(2 based on their sequences and phylogeny. A subset of 10 rice PLAs exhibited chromosomal duplication, emphasizing the role of duplication in the expansion of this gene family in rice. Microarray expression profiling revealed a number of PLA members expressing differentially and significantly under abiotic stresses and reproductive development. Comparative expression analysis with Arabidopsis PLAs revealed a high degree of functional conservation between the orthologs in two plant species, which also indicated the vital role of PLAs in stress signaling and plant development across different plant species. Moreover, sub-cellular localization of a few candidates suggests their differential localization and functional role in the lipid signaling. CONCLUSION/SIGNIFICANCE: The comprehensive analysis and expression profiling would provide a critical platform for the functional characterization of the candidate PLA genes in crop plants.

  16. A stress-associated NAC transcription factor (SlNAC35) from tomato plays a positive role in biotic and abiotic stresses.

    Science.gov (United States)

    Wang, Guodong; Zhang, Song; Ma, Xiaocui; Wang, Yong; Kong, Fanying; Meng, Qingwei

    2016-09-01

    The NAC transcription factor family participates in responses to various kinds of environmental stimuli in plants. Responses of NAC genes to abiotic stresses have been widely studied, but their functions in response to biotic stress are little reported in plants, especially in crops. In the present study, we examined the functions of a novel tomato (Solanum lycopersicum) NAC protein (SlNAC35) in abiotic and biotic stress resistance by using transgenic tobacco. Expression analysis found that SlNAC35 expression was induced by drought stress, salt stress, bacterial pathogen, and signaling molecules, suggesting its involvement in plant responses to biotic and abiotic stimuli. Moreover, transgenic lines exhibited a greater number of lateral roots and longer root length compared with Vec lines (empty vector lines) after drought and salt treatment. These results indicate that overexpression of SlNAC35 promoted root growth and development under drought and salt stresses. Higher expressions of NtARF1, NtARF2 and NtARF8 were observed under drought and salt stresses in transgenic lines, suggesting that overexpression of SlNAC35 promoted growth and development of roots in transgenic lines possibly by involving auxin signaling and by regulating NtARF expression. In addition, SlNAC35 overexpression improved resistance to bacterial pathogen in transgenic tobacco, and reactive oxygen species may be in the upstream of salicylic acid (SA) signaling in transgenic tobacco during defense response.

  17. A stress-associated NAC transcription factor (SlNAC35) from tomato plays a positive role in biotic and abiotic stresses.

    Science.gov (United States)

    Wang, Guodong; Zhang, Song; Ma, Xiaocui; Wang, Yong; Kong, Fanying; Meng, Qingwei

    2016-09-01

    The NAC transcription factor family participates in responses to various kinds of environmental stimuli in plants. Responses of NAC genes to abiotic stresses have been widely studied, but their functions in response to biotic stress are little reported in plants, especially in crops. In the present study, we examined the functions of a novel tomato (Solanum lycopersicum) NAC protein (SlNAC35) in abiotic and biotic stress resistance by using transgenic tobacco. Expression analysis found that SlNAC35 expression was induced by drought stress, salt stress, bacterial pathogen, and signaling molecules, suggesting its involvement in plant responses to biotic and abiotic stimuli. Moreover, transgenic lines exhibited a greater number of lateral roots and longer root length compared with Vec lines (empty vector lines) after drought and salt treatment. These results indicate that overexpression of SlNAC35 promoted root growth and development under drought and salt stresses. Higher expressions of NtARF1, NtARF2 and NtARF8 were observed under drought and salt stresses in transgenic lines, suggesting that overexpression of SlNAC35 promoted growth and development of roots in transgenic lines possibly by involving auxin signaling and by regulating NtARF expression. In addition, SlNAC35 overexpression improved resistance to bacterial pathogen in transgenic tobacco, and reactive oxygen species may be in the upstream of salicylic acid (SA) signaling in transgenic tobacco during defense response. PMID:26991441

  18. The effects of bacterial volatile emissions on plant abiotic stress tolerance

    OpenAIRE

    Xiao-min LIU; Zhang, Huiming

    2015-01-01

    Plant growth-promoting rhizobacteria (PGPR) are beneficial plant symbionts that have been successfully used in agriculture to increase seedling emergence, plant weight, crop yield, and disease resistance. Some PGPR strains release volatile organic compounds (VOCs) that can directly and/or indirectly mediate increases in plant biomass, disease resistance, and abiotic stress tolerance. This mini-review focuses on the enhancement of plant abiotic stress tolerance by bacterial VOCs. The review co...

  19. Regulatory roles of serotonin and melatonin in abiotic stress tolerance in plants

    OpenAIRE

    Kaur, Harmeet; Mukherjee, Soumya; Baluska, Frantisek; Bhatla, Satish C

    2015-01-01

    Understanding the physiological and biochemical basis of abiotic stress tolerance in plants has always been one of the major aspects of research aiming to enhance plant productivity in arid and semi-arid cultivated lands all over the world. Growth of stress-tolerant transgenic crops and associated agricultural benefits through increased productivity, and related ethical issues, are also the major concerns of current research in various laboratories. Interesting data on the regulation of abiot...

  20. Induction of Glutathione Synthesis and Glutathione Reductase Activity by Abiotic Stresses in Maize and Wheat

    Directory of Open Access Journals (Sweden)

    Gábor Kocsy

    2002-01-01

    Full Text Available The effect of different abiotic stresses (extreme temperatures and osmotic stress on the synthesis of glutathione and hydroxymethylglutathione, on the ratio of the reduced to oxidised forms of these thiols (GSH/GSSG, hmGSH/hmGSSG, and on the glutathione reductase (GR activity was studied in maize and wheat genotypes having different sensitivity to low temperature stress. Cold treatment induced a greater increase in total glutathione (TG content and in GR activity in tolerant genotypes of both species than in sensitive ones. The GSH/GSSG and hmGSH/hmGSSG ratios were increased by this treatment only in the frost-tolerant wheat variety. High-temperature stress increased the TG content and the GSH/GSSG ratio only in the chilling-sensitive maize genotype, but GR activity was greater after this treatment in both maize genotypes. Osmotic stress resulted in a great increase in the TG content in wheat and the GR activity in maize. The amount of total hydroxymethylglutathione increased following all stress treatments. These results indicate the involvement of these antioxidants in the stress responses of wheat and maize.

  1. Isolation and Expression Analysis of a Novel Abiotic Stress-Induced Gene W89 from Wheat

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui-yue; XU Zhao-shi; LI Lian-cheng; CHEN Ming; MA You-zhi

    2007-01-01

    Water stress and cold stress are important factors restricting plant growth. However, there is little knowledge on the function of stress-responsive genes in plants. Therefore, it is necessary to clone some important genes to study the mechanism of plant adaptation to abiotic stress for improvement of plant resistance. A putative water stress-induced gene, W89, was cloned from the cDNA library of drought-treated wheat seedlings by phage hybridization in situ, and its entire length was obtained using 5'-rapid amplification of cDNA ends (RACE) and reverse transcription-polymerase chain reaction (RT-PCR). The full-length cDNA of W89 consists of 2 392 bp and contains a 1 896 bp open reading frame (ORF) encoding a 631 amino acid protein. Southern blot analysis indicated that W89 was a single-copy gene. RT-PCR analysis revealed that the expression of W89 was upregulated by drought, cold, and abscisic acid (ABA). Amino acid sequence analysis discovered that W89 had a conserved region of DUF248 (pfam03141), which contained a methyltransferase domain with a sterile alpha motif (SAM)-binding motif. Phylogenetic analysis showed that W89 was 66% identical to Oryza sativa dehydration-responsive protein (BAD67956). It was supposed that W89 was a novel dehydration-responsive protein encoding gene. On the basis of the functions of methyltransferase and the SAM-binding motif, the SAM-binding motif of W89 was supposed to be connected with other proteins or transcription factors to transduce stress signals and finally regulate the expression of stress-responsive genes on the early stage of drought stress.

  2. Molecular characterization of BZR transcription factor family and abiotic stress induced expression profiling in Brassica rapa.

    Science.gov (United States)

    Saha, Gopal; Park, Jong-In; Jung, Hee-Jeong; Ahmed, Nasar Uddin; Kayum, Md Abdul; Kang, Jong-Goo; Nou, Ill-Sup

    2015-07-01

    BRASSINAZOLE-RESISTANT (BZR) transcription factors (TFs) are primarily well known as positive regulators of Brassinosteroid (BR) signal transduction in different plants. BR is a plant specific steroid hormone, which has multiple stress resistance functions besides various growth regulatory roles. Being an important regulator of the BR synthesis, BZR TFs might have stress resistance related activities. However, no stress resistance related functional study of BZR TFs has been reported in any crop plants so far. Therefore, this study identified 15 BZR TFs of Brassica rapa (BrBZR) from a genome-wide survey and characterized them through sequence analysis and expression profiling against several abiotic stresses. Various systematic in silico analysis of these TFs validated the fundamental properties of BZRs, where a high degree of similarity also observed with recognized BZRs of other plant species from the comparison studies. In the organ specific expression analyses, 6 BrBZR TFs constitutively expressed in flower developmental stages indicating their flower specific functions. Subsequently, from the stress resistance related expression profiles differential transcript abundance levels were observed by 6 and 11 BrBZRs against salt and drought stresses, respectively. All BrBZRs showed several folds up-regulation against exogenous ABA treatment. All BrBZRs also showed differential expression against low temperature stress treatments and these TFs were proposed as transcriptional activators of CBF cold response pathway of B. rapa. Notably, three BrBZRs gave co-responsive expression against all the stresses tested here, suggesting their multiple stress resistance related functions. Thus, the findings would be helpful in resolving the complex regulatory mechanism of BZRs in stress resistance and further functional genomics study of these potential TFs in different Brassica crops. PMID:25931321

  3. Transgenic poplar expressing codA exhibits enhanced growth and abiotic stress tolerance.

    Science.gov (United States)

    Ke, Qingbo; Wang, Zhi; Ji, Chang Yoon; Jeong, Jae Cheol; Lee, Haeng-Soon; Li, Hongbing; Xu, Bingcheng; Deng, Xiping; Kwak, Sang-Soo

    2016-03-01

    Glycine betaine (GB), a compatible solute, effectively stabilizes the structure and function of macromolecules and enhances abiotic stress tolerance in plants. We generated transgenic poplar plants (Populus alba × Populus glandulosa) expressing a bacterial choline oxidase (codA) gene under the control of the oxidative stress-inducible SWPA2 promoter (referred to as SC plants). Among the 13 SC plants generated, three lines (SC4, SC14 and SC21) were established based on codA transcript levels, tolerance to methyl viologen-mediated oxidative stress and Southern blot analysis. Growth was better in SC plants than in non-transgenic (NT) plants, which was related to elevated transcript levels of auxin-response genes. SC plants accumulated higher levels of GB under oxidative stress compared to the NT plants. In addition, SC plants exhibited increased tolerance to drought and salt stress, which was associated with increased efficiency of photosystem II activity. Finally, SC plants maintained lower levels of ion leakage and reactive oxygen species under cold stress compared to the NT plants. These observations suggest that SC plants might be useful for reforestation on global marginal lands, including desertification and reclaimed areas. PMID:26795732

  4. Speculation: Polyamines are important in abiotic stress signaling.

    Science.gov (United States)

    Pál, Magda; Szalai, Gabriella; Janda, Tibor

    2015-08-01

    The main role of polyamines was originally assumed to be as direct protective compounds important under stress conditions. Although in some cases a correlation was found between the endogenous polyamine content and stress tolerance, this relationship cannot be generalized. Polyamines should no longer be considered simply as protective molecules, but rather as compounds that are involved in a complex signaling system and have a key role in the regulation of stress tolerance. The major links in polyamine signaling may be H2O2 and NO, which are not only produced in the course of the polyamine metabolism, but also transmit signals that influence gene expression via an increase in the cytoplasmic Ca(2+) level. Polyamines can also influence Ca(2+) influx independently of the H2O2- and/or NO-mediated pathways. Furthermore, these pathways may converge. In addition, several protein kinases have been shown to be influenced at the transcriptional or post-translational level by polyamines. Individual polyamines can be converted into each other in the polyamine cycle. In addition, their metabolism is linked with other hormones or signaling molecules. However, as individual polyamines trigger different transcriptional responses, other mechanisms and the existence of polyamine-responsive elements and the corresponding transacting protein factors are also involved in polyamine-related signaling pathways.

  5. Connecting RNA Processing to Abiotic Environmental Response in Arabidopsis: the role of a polyadenylation factor

    Science.gov (United States)

    Li, Q. Q.; Xu, R.; Hunt, A. G.; Falcone, D. L.

    Plants are constantly challenged by numerous environmental stresses both biotic and abiotic It is clear that plants have evolved to counter these stresses using all but limited means We recently discovered the potential role of a messenger RNA processing factor namely the Arabidopsis cleavage and polyadenylation specificity factor 30 kDa subunit AtCPSF30 when a mutant deficient in this factor displayed altered responses to an array of abiotic stresses This AtCPSF30 mutant named oxt6 exhibited an elevated tolerance to oxidative stress Microarray experiments of oxt6 and its complemented lines revealed an altered gene expression profile among which were antioxidative defense genes Interestingly the same gene encoding AtCPSF30 can also be transcribed into a large transcript that codes for a potential splicing factor Both protein products have a domain for RNA binding and a calmodulin binding domain activities of which have been confirmed by biochemical assays Surprisingly binding of AtCPSF30 to calmodulin inhibits the RNA-binding activity of the protein Mutational analysis shows that a small part of the protein is responsible for calmodulin binding and point mutations in this region abolished both RNA binding activity and the inhibition of this activity by calmodulin Analyses of the potential splicing factor are on going and the results will be presented The interesting possibilities for both the interplay between splicing and polyadenylation and the regulation of these processes by stimuli that act through

  6. Mechanisms of silicon-mediated alleviation of abiotic stresses in higher plants: A review

    International Nuclear Information System (INIS)

    Although silicon (Si) is the second most abundant element both on the surface of the Earth's crust and in soils, it has not yet been listed among the essential elements for higher plants. However, the beneficial role of Si in stimulating the growth and development of many plant species has been generally recognized. Silicon is known to effectively mitigate various abiotic stresses such as manganese, aluminum and heavy metal toxicities, and salinity, drought, chilling and freezing stresses. However, mechanisms of Si-mediated alleviation of abiotic stresses remain poorly understood. The key mechanisms of Si-mediated alleviation of abiotic stresses in higher plants include: (1) stimulation of antioxidant systems in plants, (2) complexation or co-precipitation of toxic metal ions with Si, (3) immobilization of toxic metal ions in growth media, (4) uptake processes, and (5) compartmentation of metal ions within plants. Future research needs for Si-mediated alleviation of abiotic stresses are also discussed. - This review article overviews roles Si plays in alleviating abiotic stress in higher plants and discusses future research directions

  7. ANTHOCYANIN PIGMENTATION IN TRITICUM AESTIVUM L.: GENETIC BASIS AND ROLE UNDER ABIOTIC STRESS CONDITIONS

    Directory of Open Access Journals (Sweden)

    Tereshchenko O.Yu.

    2012-08-01

    Full Text Available Anthocyanins are secondary metabolites of plants. They have a wide range of biological activity such as antioxidant, photoprotection, osmoregulation, heavy metal ions chelation, antimicrobial and antifungal activities, which help plants to survive under different stress conditions. Bread wheat (T. aestivum L. can have purple pigmentation provided by anthocyanin compounds in different organs, such as grain pericarp, coleoptile, culm, leaf blades, leaf sheaths, glumes and anthers. However, the genetic mechanisms underlying formation of these traits as well as contribution of the pigmentation to stress tolerance have not been widely studied in wheat. The aim of the current study was to investigate molecular-genetic mechanisms underlying anthocyanin pigmentation in different wheat organs and to estimate the role of the pigmentation under different abiotic stress conditions in wheat seedlings. In the current study, near-isogenic lines (NILs: cv. ‘Saratovskaya 29’ (‘S29’ and lines i:S29Pp1Pp2PF and i:S29Pp1Pp3P developed on the ‘S29’ background but having grain pericarp coloration (genes Pp and more intense coleoptile (Rc, culm (Pc, leaf blade (Plb, leaf sheath (Pls pigmentation in comparison with ‘S29’, were used. Comparative transcriptional analysis of the five structural genes Chs, Chi, F3h, Dfr, Ans, encoding enzymes participating in the anthocyanin biosynthesis, was performed in different organs of NILs. It was shown that the presence of the Rc, Pc, Plb, Pls and Pp alleles conferring strong anthocyanin pigmentation induced more intense transcription of the structural genes, suggesting the genes Rc, Pc, Plb, Pls and Pp to play a regulatory role in anthocyanin biosynthesis network. To evaluate the role of anthocyanins in stress response at the seedling stage, growth ability of the NILs and anthocyanin content in their coleoptiles were assessed after treatments with NaCl (100 and 200 mM, CdCl2 (25 and 50 μM and 15% PEG 6000

  8. Relationship between calcium decoding elements and plant abiotic-stress resistance

    Directory of Open Access Journals (Sweden)

    Wei-Yi Song, Zheng-Bin Zhang, Hong-Bo Shao, Xiu-Lin Guo, Hong-Xing Cao, Hong-Bin Zhao, Zheng-Yan Fu, Xiao-Jun Hu

    2008-01-01

    Full Text Available Serving as an important second messenger, calcium ion has unique properties and universal ability to transmit diverse signals that trigger primary physiological actions in cells in response to hormones, pathogens, light, gravity, and stress factors. Being a second messenger of paramount significance, calcium is required at almost all stages of plant growth and development, playing a fundamental role in regulating polar growth of cells and tissues and participating in plant adaptation to various stress factors. Many researches showed that calcium signals decoding elements are involved in ABA-induced stomatal closure and plant adaptation to drought, cold, salt and other abiotic stresses. Calcium channel proteins like AtTPC1 and TaTPC1 can regulate stomatal closure. Recently some new studies show that Ca2+ is dissolved in water in the apoplast and transported primarily from root to shoot through the transpiration stream. The oscillating amplitudes of [Ca2+]o and [Ca2+]i are controlled by soil Ca2+ concentrations and transpiration rates. Because leaf water use efficiency (WUE is determined by stomatal closure and transpiration rate, so there may be a close relationship between Ca2+ transporters and stomatal closure as well as WUE, which needs to be studied. The selection of varieties with better drought resistance and high WUE plays an increasing role in bio-watersaving in arid and semi-arid areas on the globe. The current paper reviews the relationship between calcium signals decoding elements and plant drought resistance as well as other abiotic stresses for further study.

  9. Evaluation of abiotic stresses of temperate estuaries by using resident zooplankton: A community vs. population approach

    Science.gov (United States)

    Paul, Sourav; Wooldridge, Tris; Perissinotto, Renzo

    2016-03-01

    By using permanently resident zooplankton, we assessed the ecological level (i.e. community and or population) that provides more in-depth indication of the stress related to salinity and temperature fluctuations in temperate estuaries. In the semi-arid warm temperate South Africa, the Gamtoos estuary experiences a full salinity gradient maintained by irregular but relatively frequent freshwater pulses, whereas the Kromme estuary is euhaline throughout its extent and receives only occasional freshwater inputs when the storage reservoir six km upstream overtops. Changes in the species evenness index of Pielou and the abundances of estuarine resident zooplankton species were modelled against salinity and temperature variations of respective estuaries. In the Gamtoos estuary, response of individual populations provided more in-depth information regarding zooplankton variability. However the most abundant resident zooplankton i.e. Acartia longipatella a copepod was not the best predictor of the salinity and temperature fluctuations. Conversely, the Kromme estuary study provided insights into the potential vulnerability of the resident estuarine zooplankton community to cold. Further, the population level study exposed responses of specific species against salinity changes. We discuss the pros and cons of designing ecological indicators of abiotic stress based on specific species, targeted to specific ecological level, and needs of considering the frequency and magnitude of fresh water inflow in an estuary. A suggestion is to use specific taxonomic group(s) (e.g. Copepods) to better understand the abiotic stress factors of specific set of estuaries (e.g. freshwater rich/starved) until a 'one size fits all' indicator is found for temperate estuaries.

  10. The effects of bacterial volatile emissions on plant abiotic stress tolerance

    Directory of Open Access Journals (Sweden)

    Xiao-Min eLiu

    2015-09-01

    Full Text Available Plant growth-promoting rhizobacteria (PGPR are beneficial plant symbionts that have been successfully used in agriculture to increase seedling emergence, plant weight, crop yield, and disease resistance. Some PGPR strains release volatile organic compounds (VOCs that can directly and/or indirectly mediate increases in plant biomass, disease resistance, and abiotic stress tolerance. This mini-review focuses on the enhancement of plant abiotic stress tolerance by bacterial VOCs. The review considers how PGPR VOCs induce tolerance to salinity and drought stress and also how they improve sulfur and iron nutrition in plants. The potential complexities in evaluating the effects of PGPR VOCs are also discussed.

  11. Protection of in-vitro grown Arabidopsis seedlings against abiotic stresses

    OpenAIRE

    Klerk, de, G.J.M.; Pumisutapon, P.

    2008-01-01

    Severe abiotic stresses may cause permanent damage leading to death. In Arabidopsis seedlings germinating in vitro, we examined whether stress-related damage could be reduced by addition of protective low-molecular-weight compounds (trehalose and putrescine), addition of a specific signal molecule (acetylsalicylic acid), culture in the dark before and/or after the stress, and hardening mild-stress pretreatments. All four tested protective procedures increased survival after exposure to drough...

  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 str

  13. ABI-like transcription factor gene TaABL1 from wheat improves multiple abiotic stress tolerances in transgenic plants.

    Science.gov (United States)

    Xu, Dong-Bei; Gao, Shi-Qing; Ma, You-Zhi; Xu, Zhao-Shi; Zhao, Chang-Ping; Tang, Yi-Miao; Li, Xue-Yin; Li, Lian-Cheng; Chen, Yao-Feng; Chen, Ming

    2014-12-01

    The phytohormone abscisic acid (ABA) plays crucial roles in adaptive responses of plants to abiotic stresses. ABA-responsive element binding proteins (AREBs) are basic leucine zipper transcription factors that regulate the expression of downstream genes containing ABA-responsive elements (ABREs) in promoter regions. A novel ABI-like (ABA-insensitive) transcription factor gene, named TaABL1, containing a conserved basic leucine zipper (bZIP) domain was cloned from wheat. Southern blotting showed that three copies were present in the wheat genome. Phylogenetic analyses indicated that TaABL1 belonged to the AREB subfamily of the bZIP transcription factor family and was most closely related to ZmABI5 in maize and OsAREB2 in rice. Expression of TaABL1 was highly induced in wheat roots, stems, and leaves by ABA, drought, high salt, and low temperature stresses. TaABL1 was localized inside the nuclei of transformed wheat mesophyll protoplast. Overexpression of TaABL1 enhanced responses of transgenic plants to ABA and hastened stomatal closure under stress, thereby improving tolerance to multiple abiotic stresses. Furthermore, overexpression of TaABL1 upregulated or downregulated the expression of some stress-related genes controlling stomatal closure in transgenic plants under ABA and drought stress conditions, suggesting that TaABL1 might be a valuable genetic resource for transgenic molecular breeding.

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

    OpenAIRE

    Ghanashyam, Challa; Jain, Mukesh

    2009-01-01

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

  15. A wheat salinity-induced WRKY transcription factor TaWRKY93 confers multiple abiotic stress tolerance in Arabidopsis thaliana.

    Science.gov (United States)

    Qin, Yuxiang; Tian, Yanchen; Liu, Xiuzhi

    2015-08-21

    Wheat is an important crop in the world. But most of the cultivars are salt sensitive, and often adversely affected by salt stress. WRKY transcription factors play a major role in plant responses to salt stress, but the effective salinity regulatory WRKYs identified in bread wheat are limited and the mechanism of salt stress tolerance is also not well explored. Here, we identified a salt (NaCl) induced class II WRKY transcription factor TaWRKY93. Its transcript level was strongly induced by salt (NaCl) and exogenous abscisic acid (ABA). Over-expression of TaWRKY93 in Arabidopsis thaliana enhanced salt (NaCl), drought, low temperature and osmotic (mannitol) stress tolerance, mainly demonstrated by transgenic plants forming longer primary roots or more lateral roots on MS plates supplemented with NaCl and mannitol individually, higher survival rate under drought and low temperature stress. Further, transgenic plants maintained a more proline content, higher relative water content and less electrolyte leakage than the wild type plants. The transcript abundance of a series of abiotic stress-related genes was up-regulated in the TaWRKY93 transgenic plants. In summary, TaWRKY93 is a new positive regulator of abiotic stress, it may increase salinity, drought and low temperature stress tolerance through enhancing osmotic adjustment, maintaining membrane stability and increasing transcription of stress related genes, and contribute to the superior agricultural traits of SR3 through promoting root development. It can be used as a candidate gene for wheat transgenic engineering breeding against abiotic stress.

  16. 3个水稻类病变基因的逆境胁迫及激素响应特征%Abiotic Stresses and Hormones Responses in Expression of Three LMM Genes in Rice

    Institute of Scientific and Technical Information of China (English)

    肖桂青; 卢向阳; 黄荣峰; 张海文

    2015-01-01

    A few candidate lesion mimic mutant (LMM) genes had been isolated from rice. Among them, OsSP-L7, OsSPL11 and OsSPL28 encode different functional proteins, respectively. There are multiple cis-acting elements in promoter sequences of these three LMM genes in response to various stresses and hormone signaling. The expression patterns analyses using real time PCR showed that these LMM genes had no tissue specialty in expression. However, they exhibited different expression characterizations under low temperature, salt, drought, ABA, ACC, JA and SA treatments. For examples, the expression of OsSPL7 was suppressed by cold, drought , ACC and JA and induced by ABA and SA;the transcripts of OsSPL11 was inhibited by low temperature, drought and JA and enhanced significantly by SA;while the expression of OsSPL28 was strongly suppressed by JA and insensitive to low temperature. These results could provide clues for further investigating the functional mechanism of lesion mimic under hormone and abiotic stress.%水稻中已克隆出十几个控制类病变(lesion mimic, LM)性状的基因,其中以SPL (spotted leaf)命名的基因如OsSPL7、OsSPL11、OsSPL28分别编码不同功能的蛋白质。本研究首先分析OsSPL7、OsSPL11和OsSPL28启动子序列,发现均含有大量应答激素和逆境的顺式作用元件,并采用实时定量PCR检测这3个Os SPL基因在水稻不同部位的表达情况,以及逆境和激素等不同处理对它们在转录水平表达的影响。结果表明:OsSPL7、OsSPL11和OsSPL28在不同时期水稻组织中没有明显的时空差异表达;低温、盐、干旱胁迫和ABA、ACC、JA、SA四种激素在转录水平调控OsSPL7、OsSPL11和OsSPL28表达,其中OsSPL7表达受低温、干旱、ACC和JA抑制而受ABA、SA诱导,Os SPL 11表达受低温、干旱和JA抑制而受SA显著诱导,Os SPL 28表达受到JA强烈抑制而对低温不敏感。研究结果可为进一步研究激素和非生物胁迫调控植

  17. 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.

  18. 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. PMID:27105420

  19. Melatonin induces the transcripts of CBF/DREB1s and their involvement in both abiotic and biotic stresses in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Qian, Yongqiang; Tan, Dun-Xian; Reiter, Russel J; He, Chaozu

    2015-10-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a naturally occurring small molecule that acts as an important secondary messenger in plant stress responses. However, the mechanism underlying the melatonin-mediated signaling pathway in plant stress responses has not been established. C-repeat-binding factors (CBFs)/Drought response element Binding 1 factors (DREB1s) encode transcription factors that play important roles in plant stress responses. This study has determined that endogenous melatonin and transcripts level of CBFs (AtCBF1, AtCBF2, and AtCBF3) in Arabidopsis leaves were significantly induced by salt, drought, and cold stresses and by pathogen Pseudomonas syringe pv. tomato (Pst) DC3000 infection. Moreover, both exogenous melatonin treatment and overexpression of CBFs conferred enhanced resistance to both abiotic and biotic stresses in Arabidopsis. Notably, AtCBFs and exogenous melatonin treatment positively regulated the mRNA expression of several stress-responsive genes (COR15A, RD22, and KIN1) and accumulation of soluble sugars content such as sucrose in Arabidopsis under control and stress conditions. Additionally, exogenous sucrose also conferred improved resistance to both abiotic and biotic stresses in Arabidopsis. Taken together, this study indicates that AtCBFs confer enhanced resistance to both abiotic and biotic stresses, and AtCBF-mediated signaling pathway and sugar accumulation may be involved in melatonin-mediated stress response in Arabidopsis, at least partially.

  20. Melatonin induces the transcripts of CBF/DREB1s and their involvement in both abiotic and biotic stresses in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Qian, Yongqiang; Tan, Dun-Xian; Reiter, Russel J; He, Chaozu

    2015-10-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a naturally occurring small molecule that acts as an important secondary messenger in plant stress responses. However, the mechanism underlying the melatonin-mediated signaling pathway in plant stress responses has not been established. C-repeat-binding factors (CBFs)/Drought response element Binding 1 factors (DREB1s) encode transcription factors that play important roles in plant stress responses. This study has determined that endogenous melatonin and transcripts level of CBFs (AtCBF1, AtCBF2, and AtCBF3) in Arabidopsis leaves were significantly induced by salt, drought, and cold stresses and by pathogen Pseudomonas syringe pv. tomato (Pst) DC3000 infection. Moreover, both exogenous melatonin treatment and overexpression of CBFs conferred enhanced resistance to both abiotic and biotic stresses in Arabidopsis. Notably, AtCBFs and exogenous melatonin treatment positively regulated the mRNA expression of several stress-responsive genes (COR15A, RD22, and KIN1) and accumulation of soluble sugars content such as sucrose in Arabidopsis under control and stress conditions. Additionally, exogenous sucrose also conferred improved resistance to both abiotic and biotic stresses in Arabidopsis. Taken together, this study indicates that AtCBFs confer enhanced resistance to both abiotic and biotic stresses, and AtCBF-mediated signaling pathway and sugar accumulation may be involved in melatonin-mediated stress response in Arabidopsis, at least partially. PMID:26182834

  1. AtMYB12 regulates flavonoids accumulation and abiotic stress tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Feibing; Kong, Weili; Wong, Gary; Fu, Lifeng; Peng, Rihe; Li, Zhenjun; Yao, Quanhong

    2016-08-01

    In plants, transcriptional regulation is the most important tool for modulating flavonoid biosynthesis. The AtMYB12 gene from Arabidopsis thaliana has been shown to regulate the expression of key enzyme genes involved in flavonoid biosynthesis, leading to the increased accumulation of flavonoids. In this study, the codon-optimized AtMYB12 gene was chemically synthesized. Subcellular localization analysis in onion epidermal cells indicated that AtMYB12 was localized to the nucleus. Its overexpression significantly increased accumulation of flavonoids and enhanced salt and drought tolerance in transgenic Arabidopsis plants. Real-time quantitative PCR (qRT-PCR) analysis showed that overexpression of AtMYB12 resulted in the up-regulation of genes involved in flavonoid biosynthesis, abscisic acid (ABA) biosynthesis, proline biosynthesis, stress responses and ROS scavenging under salt and drought stresses. Further analyses under salt and drought stresses showed significant increases of ABA, proline content, superoxide dismutase (SOD) and peroxidase (POD) activities, as well as significant reduction of H2O2 and malonaldehyde (MDA) content. The results demonstrate the explicit role of AtMYB12 in conferring salt and drought tolerance by increasing the levels of flavonoids and ABA in transgenic Arabidopsis. The AtMYB12 gene has the potential to be used to enhance tolerance to abiotic stresses in plants. PMID:27033553

  2. A Cyanobacterium Synechocystis sp. PCC 6803 Glutaredoxin Gene (slr1562 Protects Escherichia coli against Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    Ahmed Gaber

    2012-01-01

    Full Text Available Problem statement: Glutaredoxins (GRXs are ubiquitous small heat stable glutathione-dependent oxidoreductase enzymes that play a crucial role in plant development and response to oxidative stress. Approach: Cyanobacterium Synechocystis strain PCC 6803 contains two genes (slr1562 and ssr2061 encoding glutaredoxins. In the present investigation the slr1562 gene (grxC was isolated and characterized. Results: The results revealed that the amino acid sequence deduced from GrxC protein share high identity with those of GRXs from other organisms and contain the consensus GRX family domain with a CPFC active site. Northern blotting analysis revealed that the expression of slr1562 gene could be induced by oxidative and salt stresses. Moreover, the protein GrxC was successfully overexpressed as a soluble fraction in Escherichia coli JM109. The over-expression of GrxC in Escherichia coli cells significantly increased resistance of cells to oxidative, drought and salt stresses. Conclusion/Recommendations: These results suggest that the slr1562 gene could play an important role in regulating abiotic tolerance against oxidative, drought and salt stresses in different organisms.

  3. Divergent DNA Methylation Patterns Associated with Abiotic Stress in Hevea brasiliensis

    Institute of Scientific and Technical Information of China (English)

    Thomas K. Uthup; Mlnlmol Ravindran; K. Bini; Saha Thakurdas

    2011-01-01

    Cytosine methylation is a fundamental epigenetic mechanism for gene-expression regulation and development in plants.Here,we report for the first time the identification of DNA methylation patterns and their putative relationship with abiotic stress in the tree crop Hevea brasiliensis (source of 99% of natural rubber in the world).Regulatory sequences of four major genes involved in the mevalonate pathway (rubber biosynthesis pathway) and one general defense-related gene of three high-yielding popular rubber clones grown at two different agroclimatic conditions were analyzed for the presence of methylation.We found several significant variations in the methylation pattern at core DNA binding motifs within all the five genes.Several consistent clone-specific and location-specific methylation patterns were identified.The differences in methylation pattern observed at certain pivotal cis-regulatory sites indicate the direct impact of stress on the genome and support the hypothesis of site-specific stress-induced DNA methylation.It is assumed that some of the methylation patterns observed may be involved in the stress-responsive mechanism in plants by which they adapt to extreme conditions.The study also provide clues towards the existence of highly divergent phenotypic characters among Hevea clones despite their very similar genetic make-up.Altogether,the observations from this study prove beyond doubt that there exist epigenetic variations in Hevea and environmental factors play a significant role in the induction of site-specific epigenetic mutations in its genome.

  4. Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress

    KAUST Repository

    Liu, Junwei

    2015-02-26

    Main conclusion: Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress.Abstract: Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators of environmental stimuli in resource allocation processes; to contribute to adaptive adjustments, therefore, their pathway must be responsive to environmental cues. To investigate the relationship between SLs and abiotic stress in Lotus japonicus, we compared wild-type and SL-depleted plants, and studied SL metabolism in roots stressed osmotically and/or phosphate starved. SL-depleted plants showed increased stomatal conductance, both under normal and stress conditions, and impaired resistance to drought associated with slower stomatal closure in response to abscisic acid (ABA). This confirms that SLs contribute to drought resistance in species other than Arabidopsis. However, we also observed that osmotic stress rapidly and strongly decreased SL concentration in tissues and exudates of wild-type Lotus roots, by acting on the transcription of biosynthetic and transporter-encoding genes and independently of phosphate abundance. Pre-treatment with exogenous SLs inhibited the osmotic stress-induced ABA increase in wild-type roots and down-regulated the transcription of the ABA biosynthetic gene LjNCED2. We propose that a transcriptionally regulated, early SL decrease under osmotic stress is needed (but not sufficient) to allow the physiological increase of ABA in roots. This work shows that SL metabolism and effects on ABA are seemingly opposite in roots and shoots under stress.

  5. Identification of plant genes for abiotic stress resistance

    NARCIS (Netherlands)

    Dixit, S.A.

    2008-01-01

    As water and salt stresses occur frequently and can affect many habitats, plants have developed several strategies to cope with these challenges: either adaptation mechanisms, which allow them to survive the adverse conditions, or specific growth habits to avoid stress conditions. Stress-tolerant pl

  6. Induction of Glutathione Synthesis and Glutathione Reductase Activity by Abiotic Stresses in Maize and Wheat

    OpenAIRE

    Gabor Kocsy; Gabriella Szalai; Gabor Galiba

    2002-01-01

    The effect of different abiotic stresses (extreme temperatures and osmotic stress) on the synthesis of glutathione and hydroxymethylglutathione, on the ratio of the reduced to oxidised forms of these thiols (GSH/GSSG, hmGSH/hmGSSG), and on the glutathione reductase (GR) activity was studied in maize and wheat genotypes having different sensitivity to low temperature stress. Cold treatment induced a greater increase in total glutathione (TG) content and in GR activity in tolerant genotypes of ...

  7. Comprehensive analysis of trihelix genes and their expression under biotic and abiotic stresses in Populus trichocarpa

    Science.gov (United States)

    Wang, Zhanchao; Liu, Quangang; Wang, Hanzeng; Zhang, Haizhen; Xu, Xuemei; Li, Chenghao; Yang, Chuanping

    2016-01-01

    Trihelix genes play important roles in plant growth and development and responses to biotic and abiotic stresses. Here, we identified 56 full-length trihelix genes in Populus trichocarpa and classified them into five groups. Most genes within a given group had similar gene structures and conserved motifs. The trihelix genes were unequally distributed across 19 different linkage groups. Fifteen paralogous pairs were identified, 14 of which have undergone segmental duplication events. Promoter cis-element analysis indicated that most trihelix genes contain stress- or phytohormone-related cis-elements. The expression profiles of the trihelix genes suggest that they are primarily expressed in leaves and roots. Quantitative real-time reverse transcription polymerase chain reaction analysis indicated that members of the trihelix gene family are significantly induced in response to osmotic, abscisic acid, salicylic acid, methyl jasmonate and pathogen infection. PtrGT10 was identified as a target gene of miR172d, which is involved in the osmotic response. Repression of PtrGT10 could increase reactive oxygen species scavenging ability and decrease cell death. This study provides novel insights into the phylogenetic relationships and functions of the P. trichocarpa trihelix genes, which will aid future functional studies investigating the divergent roles of trihelix genes belonging to other species. PMID:27782188

  8. Mutational analysis to dissect oxidative and abiotic stress in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    A genetic approach was used to identify mutants more tolerant to oxidative and abiotic stress. Large collections of Arabidopsis thaliana mutant lines generated by chemical and T-DNA mutagenesis were screened for survivors under conditions that trigger oxidative stress-induced programmed cell death (PCD). The fungal AAL-toxin triggers PCD through perturbations of sphingolipid metabolism in AAL-toxin-sensitive plants. While Arabidopsis is relatively insensitive to the toxin, the loh2 mutant is sensitive to AAL-toxin due to knockout of a gene involved in sphingolipid metabolism. EMS mutagenesis of loh2 resulted in second-site mutants that are more tolerant than loh2 to the toxin. Nine of these mutants were characterized towards their response to oxidative stress-induced cell death. Either application of the catalase inhibitor aminotriazole, leading to H2O2 accumulation was used, or paraquat, leading to superoxide radicals generation. Some mutants were more tolerant to aminotriazole, paraquat, or both herbicides. One of the mutants with tolerance to both aminotriazole and paraquat, called atr1 (AAL-toxin-resistant 1), was subjected to microarray analyses under conditions that trigger cell death in loh2 and no visible damage in atr1. Majority of the genes showed similar expression pattern in both mutants. Genes encoding for nitrate and ammonium transporters, peroxidases, transcription factors and DNAJ /DNA K were upregulated, while genes related to cell wall extension and cell growth were downregulated in both mutants. Genes from the heat-shock regulon were more clearly induced in loh2. In another approach, T-DNA mutagenized wild type seeds were germinated on plant growth media supplemented with aminotriazole and one survivor was recovered. As many types of abiotic stresses are connected with oxidative stress, this T-DNA mutant together with atr1 and their respective controls were subjected to chilling stress. Both the T-DNA mutant and atr1 showed reduced chilling

  9. A seed preferential heat shock transcription factor from wheat provides abiotic stress tolerance and yield enhancement in transgenic Arabidopsis under heat stress environment.

    Directory of Open Access Journals (Sweden)

    Harsh Chauhan

    Full Text Available Reduction in crop yield and quality due to various abiotic stresses is a worldwide phenomenon. In the present investigation, a heat shock factor (HSF gene expressing preferentially in developing seed tissues of wheat grown under high temperatures was cloned. This newly identified heat shock factor possesses the characteristic domains of class A type plant HSFs and shows high similarity to rice OsHsfA2d, hence named as TaHsfA2d. The transcription factor activity of TaHsfA2d was confirmed through transactivation assay in yeast. Transgenic Arabidopsis plants overexpressing TaHsfA2d not only possess higher tolerance towards high temperature but also showed considerable tolerance to salinity and drought stresses, they also showed higher yield and biomass accumulation under constant heat stress conditions. Analysis of putative target genes of AtHSFA2 through quantitative RT-PCR showed higher and constitutive expression of several abiotic stress responsive genes in transgenic Arabidopsis plants over-expressing TaHsfA2d. Under stress conditions, TaHsfA2d can also functionally complement the T-DNA insertion mutants of AtHsfA2, although partially. These observations suggest that TaHsfA2d may be useful in molecular breeding of crop plants, especially wheat, to improve yield under abiotic stress conditions.

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

    Science.gov (United States)

    Singh, Raksha; Jwa, Nam-Soo

    2013-11-01

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

  11. Comprehensive expression profiling of rice tetraspanin genes reveals diverse roles during development and abiotic stress

    Directory of Open Access Journals (Sweden)

    Balaji eM

    2015-12-01

    Full Text Available Tetraspanin family is comprised of evolutionarily conserved integral membrane proteins. The incredible ability of tetraspanins to form ‘micro domain complexes’ and their preferential targeting to membranes emphasizes their active association with signal recognition and communication with neighboring cells, thus acting as key modulators of signaling cascades. In animals, tetraspanins are associated with multitude of cellular processes. Unlike animals, the biological relevance of tetraspanins in plants has not been well investigated. In Arabidopsis tetraspanins are known to contribute in important plant development processes such as leaf morphogenesis, root and floral organ formation. In the present study we investigated the genomic organization, chromosomal distribution, phylogeny and domain structure of 15 rice tetraspanin proteins (OsTETs. OsTET proteins had similar domain structure and signature ‘GCCK/R’ motif as reported in Arabidopsis. Comprehensive expression profiling of OsTET genes suggested their possible involvement during rice development. While OsTET9 and 10 accumulated predominantly in flowers, OsTET5, 8 and 12 were preferentially expressed in root tissues. Noticeably, seven OsTETs exhibited more than 2-fold up regulation at early stages of flag leaf senescence in rice. Furthermore, several OsTETs were differentially regulated in rice seedlings exposed to abiotic stresses, exogenous treatment of hormones and nutrient deprivation. Transient subcellular localization studies of eight OsTET proteins in tobacco epidermal cells showed that these proteins localized in plasma membrane. The present study provides valuable insights into the possible roles of tetraspanins in regulating development and defining response to abiotic stresses in rice. Targeted proteomic studies would be useful in identification of their interacting partners under different conditions and ultimately their biological function in plants

  12. Unveiling the Redox Control of Plant Reproductive Development during Abiotic Stress

    Science.gov (United States)

    Zinta, Gaurav; Khan, Asif; AbdElgawad, Hamada; Verma, Vipasha; Srivastava, Ashish Kumar

    2016-01-01

    Plants being sessile in nature are often challenged to various abiotic stresses including temperature fluctuations, water supply, salinity, and nutrient availability. Exposure of plants to such environmental perturbations result in the formation of reactive oxygen species (ROS) in cells. To scavenge ROS, enzymatic and molecular antioxidants are produced at a cellular level. ROS act as a signaling entity at lower concentrations maintaining normal growth and development, but if their levels increase beyond certain threshold, they produce toxic effects in plants. Some developmental stages, such as development of reproductive organs are more sensitive to abiotic stress than other stages of growth. As success of plant reproductive development is directly correlated with grain yield, stresses coinciding with reproductive phase results in the higher yield losses. In this article, we summarize the redox control of plant reproductive development, and elaborate how redox homeostasis is compromised during abiotic stress exposure. We highlight why more emphasis should be given to understand redox control of plant reproductive organ development during abiotic stress exposure96to engineer crops with better crop yield. We specifically discuss the role of ROS as a signaling molecule and its cross-talk with other signaling molecules such as hormones and sugars. PMID:27379102

  13. Sugar beet M14 glyoxalase I gene can enhance plant tolerance to abiotic stresses.

    Science.gov (United States)

    Wu, Chuan; Ma, Chunquan; Pan, Yu; Gong, Shilong; Zhao, Chenxi; Chen, Sixue; Li, Haiying

    2013-05-01

    Glyoxalase I is the first enzyme of the glyoxalase system that can detoxify methylglyoxal, a cytotoxic compound increased rapidly under stress conditions. Here we report cloning and characterization of a glyoxalase I from sugar beet M14 line (an interspecific hybrid between a wild species Beta corolliflora Zoss and a cultivated species B. vulgaris L). The full-length gene BvM14-glyoxalase I has 1,449 bp in length with an open reading frame of 1,065 bp encoding 354 amino acids. Sequence analysis shows the conserved glyoxalase I domains, metal and glutathione binding sites and secondary structure (α-helixes and β-sheets). The BvM14-glyoxalase I gene was ubiquitously expressed in different tissues of sugar beet M14 line and up-regulated in response to salt, mannitol and oxidative stresses. Heterologous expression of BvM14-glyoxalase I could increase E. coli tolerance to methylglyoxal. Transgenic tobacco plants constitutively expressing BvM14-glyoxalase I were generated. Both leaf discs and seedlings showed significant tolerance to methylglyoxal, salt, mannitol and H2O2. These results suggest an important role of BvM14-glyoxalase I in cellular detoxification and tolerance to abiotic stresses.

  14. Sugar beet M14 glyoxalase I gene can enhance plant tolerance to abiotic stresses.

    Science.gov (United States)

    Wu, Chuan; Ma, Chunquan; Pan, Yu; Gong, Shilong; Zhao, Chenxi; Chen, Sixue; Li, Haiying

    2013-05-01

    Glyoxalase I is the first enzyme of the glyoxalase system that can detoxify methylglyoxal, a cytotoxic compound increased rapidly under stress conditions. Here we report cloning and characterization of a glyoxalase I from sugar beet M14 line (an interspecific hybrid between a wild species Beta corolliflora Zoss and a cultivated species B. vulgaris L). The full-length gene BvM14-glyoxalase I has 1,449 bp in length with an open reading frame of 1,065 bp encoding 354 amino acids. Sequence analysis shows the conserved glyoxalase I domains, metal and glutathione binding sites and secondary structure (α-helixes and β-sheets). The BvM14-glyoxalase I gene was ubiquitously expressed in different tissues of sugar beet M14 line and up-regulated in response to salt, mannitol and oxidative stresses. Heterologous expression of BvM14-glyoxalase I could increase E. coli tolerance to methylglyoxal. Transgenic tobacco plants constitutively expressing BvM14-glyoxalase I were generated. Both leaf discs and seedlings showed significant tolerance to methylglyoxal, salt, mannitol and H2O2. These results suggest an important role of BvM14-glyoxalase I in cellular detoxification and tolerance to abiotic stresses. PMID:23203352

  15. An ATL78-Like RING-H2 Finger Protein Confers Abiotic Stress Tolerance through Interacting with RAV2 and CSN5B in Tomato.

    Science.gov (United States)

    Song, Jianwen; Xing, Yali; Munir, Shoaib; Yu, Chuying; Song, Lulu; Li, Hanxia; Wang, Taotao; Ye, Zhibiao

    2016-01-01

    RING finger proteins play an important role in plant adaptation to abiotic stresses. In the present study, a wild tomato (Solanum habrochaites) cold-induced RING-H2 finger gene, ShATL78L, was isolated, which has been identified as an abiotic stress responsive gene in tomato. The results showed that ShATL78L was constitutively expressed in various tissues such as root, leaf, petiole, stem, flower, and fruit. Cold stress up-regulated ShATL78L in the cold-tolerant S. habrochaites compared to the susceptible cultivated tomato (S. lycopersicum). Furthermore, ShATL78L expression was also regulated under different stresses such as drought, salt, heat, wound, osmotic stress, and exogenous hormones. Functional characterization showed that cultivated tomato overexpressing ShATL78L had improved tolerance to cold, drought and oxidative stresses compared to the wild-type and the knockdown lines. To understand the underlying molecular mechanism of ShATL78L regulating abiotic stress responses, we performed yeast one-hybrid and two-hybrid assays and found that RAV2 could bind to the promoter of ShATL78L and activates/alters its transcription, and CSN5B could interact with ShATL78L to regulate abiotic stress responses. Taken together, these results show that ShATL78L plays an important role in regulating plant adaptation to abiotic stresses through bound by RAV2 and interacting with CSN5B. Highlight: RAV2 binds to the promoter of ShATL78L to activates/alters its transcription to adapt the environmental conditions; furthermore, ShATL78L interacts with CSN5B to regulate the stress tolerance. PMID:27621744

  16. Priming as a mechanism behind induced resistance against pathogens, insects and abiotic stress

    NARCIS (Netherlands)

    Ton, J.; Ent, S. van der; Hulten, M.H.A. van; Pozo, M.; Oosten, V. van; Loon, L.C. van; Mauch-Mani, B.; Turlings, T.C.J.; Pieterse, C.M.J.

    2009-01-01

    Upon treatment with a resistance-inducing agent, plants acquire an enhanced defensive capacity that results in a faster and/or stronger defence reaction at the moment the plant is exposed to biotic or abiotic stress. This phenomenon is commonly known as priming and has been associated with different

  17. 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 ...

  18. Role of Nitric oxide in regulation of H2O2 mediating tolerance of plants to abiotic stress: A synergistic signaling approach

    Directory of Open Access Journals (Sweden)

    Taqi Ahmed Khan

    2011-05-01

    Full Text Available The relationship between abiotic stress, nitric oxide (NO and Hydrogen peroxide (H2O2 is a challenging one. It is now clear that H2O2 and NO function as signaling molecules in plants. A wide range of abiotic stresses results in H2O2 generation, from a variety of sources and it has many essential roles in plant metabolism but at the same time, accumulation related to virtually any environmental stress is potentially damaging. NO is gaining increasing attention as a regulator of diverse pathophysiological processes in plant science, mainly due to its properties (free radicals, small size, no charge, short-lived, and highly diffusible across biological membranes and multifunctional roles in plant growth, development and regulation of remarkably broad myriad of plant cellular mechanisms. Various abiotic stresses can induce NO synthesis, but its origin and mode of action in plants have not yet been completely resolved. Recent studies on NO production have tended to high light the questions that still remain unanswered rather than telling us more about NO metabolism. But regarding NO-H2O2 signaling and functions, new findings have given an impression of the intricacy of NO-H2O2 related signaling networks against abiotic stresses. Cellular responses to NO-H2O2 are complex, with considerable cross-talk between responses to several abiotic stresses. In last few years, the role of NO in H2O2 mediating tolerance in plants to abiotic stress has established much consideration.

  19. Stomata prioritize their responses to multiple biotic and abiotic signal inputs.

    Directory of Open Access Journals (Sweden)

    Xiaobin Ou

    Full Text Available Stomata are microscopic pores in leaf epidermis that regulate gas exchange between plants and the environment. Being natural openings on the leaf surface, stomata also serve as ports for the invasion of foliar pathogenic bacteria. Each stomatal pore is enclosed by a pair of guard cells that are able to sense a wide spectrum of biotic and abiotic stresses and respond by precisely adjusting the pore width. However, it is not clear whether stomatal responses to simultaneously imposed biotic and abiotic signals are mutually dependent on each other. Here we show that a genetically engineered Escherichia coli strain DH5α could trigger stomatal closure in Vicia faba, an innate immune response that might depend on NADPH oxidase-mediated ROS burst. DH5α-induced stomatal closure could be abolished or disguised under certain environmental conditions like low [CO2], darkness, and drought, etc. Foliar spraying of high concentrations of ABA could reduce stomatal aperture in high humidity-treated faba bean plants. Consistently, the aggressive multiplication of DH5α bacteria in Vicia faba leaves under high humidity could be alleviated by exogenous application of ABA. Our data suggest that a successful colonization of bacteria on the leaf surface is correlated with stomatal aperture regulation by a specific set of environmental factors.

  20. A comprehensive genome-wide study on tissue-specific and abiotic stress-specific miRNAs in Triticum aestivum.

    Directory of Open Access Journals (Sweden)

    Ritu Pandey

    Full Text Available Productivity of wheat crop is largely dependent on its growth and development that, in turn, is mainly regulated by environmental conditions, including abiotic stress factors. miRNAs are key regulators of gene expression networks involved in diverse aspects of development and stress responses in plants. Using high-throughput sequencing of eight small RNA libraries prepared from diverse abiotic stresses and tissues, we identified 47 known miRNAs belonging to 20 families, 49 true novel and 1030 candidate novel miRNAs. Digital gene expression analysis revealed that 257 miRNAs exhibited tissue-specific expression and 74 were associated with abiotic stresses. Putative target genes were predicted for miRNAs identified in this study and their grouping into functional categories indicated that the putative targets were involved in diverse biological processes. RLM-RACE of predicted targets of three known miRNAs (miR156, miR160 and miR164 confirmed their mRNA cleavage, thus indicating their regulation at post-transcriptional level by the corresponding miRNAs. Mapping of the sequenced data onto the wheat progenitors and closely related monocots revealed a large number of evolutionary conserved miRNAs. Additional expression profiling of some of these miRNAs in other abiotic stresses underline their involvement in multiple stresses. Our findings provide valuable resource for an improved understanding of the role of miRNAs in stress tolerance as well as plant development.

  1. Resistance to biotic and abiotic stresses in avena

    OpenAIRE

    Sánchez Martín, Javier

    2012-01-01

    Oat is an important grain and forage crop cultivated over than 9 million hectares globally. However, drought and biotrophic fungal diseases, such as crown rust (Puccinia coronata f. sp. avenae) and powdery mildew (Blumeria graminis f. sp. avenae) seriously threaten oat production. To combat this, agricultural scientists must develop a comprehensive understanding of the mechanisms through which plants can tolerate/resist stress and translate this to crop breeding programmes. Thu...

  2. Characterization of abiotic stress genes from different species of eucalyptus

    International Nuclear Information System (INIS)

    The stresses causing dehydration damage to the plant cell like cold, drought, and high salinity are the most frequent environmental stresses that influence plant growth, development and restraining productivity in cultivated areas world-wide. Many drought, salinity and cold inducible genes causing tolerance to environmental stresses in many plants include Dehydrin1 (DHN1), Dehydrin2 (DHN2), Dehydrin10 (DHN10), putative phosphate transporter (Ecpt2), choline monooxygenase (CMO) and DREB/CBF1c genes. Gene specific primer pairs were designed for each gene using DNAStar software. These genes were amplified from different species of eucalyptus such as Eucalyptus camaldulensis, E. globulus, E. tereticornis and E. gunii through PCR. Dehydrin2 gene of E. camaldulensis and dehydrin10 gene of E. globulus were cloned using the TA Cloning Kit with pCR 2.1 vector and sequenced. The Dehydrin genes sequences were submitted to GeneBank: Eucalyptus globulus dehydrin10 gene (Accession No. HG915712) and E. camaldulensis dehydrin 2 gene (Accession No. HG813113). The amino acid sequence of Dehydrin10 from E. globulus showed 97% homology to E. globulus DHN10 (JN052210) and Dehydrin2 from E. camaldulensis presented 94% homology to E. globulus DHN2 (JN052209). These genes can be employed in generating drought resistant crop plants. (author)

  3. Monitoring expression profiles of rice (Oryza sativa L.) genes under abiotic stresses using cDNA Microarray Analysis (abstract)

    International Nuclear Information System (INIS)

    Transcript regulation in response to cold, drought, high salinity and ABA application was investigated in rice (Oryza sativa L., Nipponbare) with microarray analysis including approx. 1700 independent DNA elements derived from three cDNA libraries constructed from 15-day old rice seedlings stressed with drought, cold and high salinity. A total of 141 non-redundant genes were identified, whose expression ratios were more than three-fold compared with the control genes for at least one of stress treatments in microarray analysis. However, after RNA gel blot analysis, a total of 73 genes were identified, among them the transcripts of 36, 62, 57 and 43 genes were found increased after cold, drought, high salinity and ABA application, respectively. Sixteen of these identified genes have been reported previously to be stress inducible in rice, while 57 of which are novel that have not been reported earlier as stress responsive in rice. We observed a strong association in the expression patterns of stress responsive genes and found 15 stress inducible genes that responded to all four treatments. Based on Venn diagram analysis, 56 genes were induced by both drought and high salinity, whereas 22 genes were upregulated by both cold and high salinity stress. Similarly 43 genes were induced by both drought stress and ABA application, while only 17 genes were identified as cold and ABA inducible genes. These results indicated the existence of greater cross talk between drought, ABA and high salinity stress signaling processes than those between cold and ABA, and cold and high salinity stress signaling pathways. The cold, drought, high salinity and ABA inducible genes were classified into four gene groups from their expression profiles. Analysis of data enabled us to identify a number of promoters and possible cis-acting DNA elements of several genes induced by a variety of abiotic stresses by combining expression data with genomic sequence data of rice. Comparative analysis of

  4. Cytosine methylation alteration in natural populations of Leymus chinensis induced by multiple abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Yingjie Yu

    Full Text Available BACKGROUND: Human activity has a profound effect on the global environment and caused frequent occurrence of climatic fluctuations. To survive, plants need to adapt to the changing environmental conditions through altering their morphological and physiological traits. One known mechanism for phenotypic innovation to be achieved is environment-induced rapid yet inheritable epigenetic changes. Therefore, the use of molecular techniques to address the epigenetic mechanisms underpinning stress adaptation in plants is an important and challenging topic in biological research. In this study, we investigated the impact of warming, nitrogen (N addition, and warming+nitrogen (N addition stresses on the cytosine methylation status of Leymus chinensis Tzvel. at the population level by using the amplified fragment length polymorphism (AFLP, methylation-sensitive amplified polymorphism (MSAP and retrotransposon based sequence-specific amplification polymorphism (SSAP techniques. METHODOLOGY/PRINCIPAL FINDINGS: Our results showed that, although the percentages of cytosine methylation changes in SSAP are significantly higher than those in MSAP, all the treatment groups showed similar alteration patterns of hypermethylation and hypomethylation. It meant that the abiotic stresses have induced the alterations in cytosine methylation patterns, and the levels of cytosine methylation changes around the transposable element are higher than the other genomic regions. In addition, the identification and analysis of differentially methylated loci (DML indicated that the abiotic stresses have also caused targeted methylation changes at specific loci and these DML might have contributed to the capability of plants in adaptation to the abiotic stresses. CONCLUSIONS/SIGNIFICANCE: Our results demonstrated that abiotic stresses related to global warming and nitrogen deposition readily evoke alterations of cytosine methylation, and which may provide a molecular basis for rapid

  5. Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

    Science.gov (United States)

    Nie, Qiong; Gao, Guo-Li; Fan, Qing-jie; Qiao, Guang; Wen, Xiao-Peng; Liu, Tao; Peng, Zhi-Jun; Cai, Yong-Qiang

    2015-05-25

    Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.g. drought, heat and poor soil. However, involvement of the pitaya catalase gene (HuCAT) in tolerance to abiotic stresses is unknown. In the present study, a full-length HuCAT3 cDNA (1870 bp) was isolated from pitaya based on our previous microarray data and RACE method. The cDNA sequence and deduced amino acid sequence shared 73-77% and 75-80% identity with other plant catalases, respectively. HuCAT3 contains conserved catalase family domain and catalytic sites. Pairwise comparison and phylogenetic analysis indicated that HuCAT3 is most similar to Eriobotrya japonica CAT, followed by Dimocarpus longan CAT and Nicotiana tabacum CAT1. Expression profile analysis demonstrated that HuCAT3 is mainly expressed in green cotyledons and mature stems, and was regulated by H2O2, drought, cold and salt stress, whereas, its expression patterns and maximum expression levels varied with stress types. HuCAT activity increased as exposure to the tested stresses, and the fluctuation of HuCAT activity was consistent with HuCAT3 mRNA abundance (except for 0.5 days upon drought stress). HuCAT3 mRNA elevations and HuCAT activities changes under cold stress were also in conformity with the cold tolerances among the four genotypes. The obtained results confirmed a major role of HuCAT3 in abiotic stress response of pitaya. This may prove useful in understanding pitaya's high tolerance to abiotic stresses at molecular level.

  6. Corynebacterium pseudotuberculosis RNA-seq data from abiotic stresses

    OpenAIRE

    Pablo H.C.G. de Sá; Veras, Adonney A. O.; Carneiro, Adriana R.; Baraúna, Rafael A.; Luís C. Guimarães; Pinheiro, Kenny C.; Pinto, Anne C.; Soares, Siomar C.; Schneider, Maria P. C.; Vasco Azevedo; Artur Silva; Ramos, Rommel T. J.

    2015-01-01

    Corynebacterium pseudotuberculosis causes significant loss to goat and sheep farmers because it is the causal agent of the infectious disease caseous lymphadenitis, which may lead to outcomes ranging from skin injury to animal death (Ruiz et al., 2011) [1]. This bacterium was grown under osmotic (2 M), acid (pH) and heat (50 °C) stress and under control (Normal-BHI brain heart infusion) conditions, which simulate the conditions faced by the bacteria during the infectious process. Subsequently...

  7. Chemiluminescent examination of abiotic oxidative stress of watercress.

    Science.gov (United States)

    Beals, Christopher; Byl, Thomas

    2014-04-01

    Watercress (Nasturtium officinale) is an aquatic plant that readily bioaccumulates heavy metals that may be found in contaminated aquatic systems. Toxic effects of contaminants on the physiological processes cause changes in oxidase enzymatic activity in watercress, which can be measured with a luminometer. The luminometer uses the reaction produced when peroxidases break down hydrogen peroxide into water and an oxygen radical. The resulting oxyradical binds to and oxidizes phenolic groups, producing a measureable luminescent reaction. Nasturtium officinale plants were exposed to 3 different concentrations of heavy metals, including lead, nickel, copper, and manganese for 24 h, 48 h, and 72 h. Aquatic exposure to the 4 heavy metals caused a significant increase in oxidative enzyme production. Fluorometric and morphometric measurements were also conducted to compare plant stress with the oxidative enzyme analyses. Fluorometric measurements performed on plants stressed by exposure to heavy metals revealed no significant decreases in photosystem II efficiency. Morphometric measurements of root length showed decreased root growth resulting from exposures to Ni, Cu, and Mn. PMID:24306856

  8. Auxin response under osmotic stress.

    Science.gov (United States)

    Naser, Victoria; Shani, Eilon

    2016-08-01

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

  9. Auxin response under osmotic stress.

    Science.gov (United States)

    Naser, Victoria; Shani, Eilon

    2016-08-01

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

  10. Protective function of nitric oxide on marine phytoplankton under abiotic stresses.

    Science.gov (United States)

    Li, Peifeng; Liu, Chun-Ying; Liu, Huanhuan; Zhang, Qiang; Wang, Lili

    2013-09-01

    As an important signaling molecule, nitric oxide (NO) plays diverse physiological functions in plants, which has gained particular attention in recent years. We investigated the roles of NO in the growth of marine phytoplankton Platymonas subcordiforms and Skeletonema costatum under abiotic stresses. The growth of these two microalgae was obviously inhibited under non-metal stress (sodium selenium, Na2SeO3), heavy metal stress (lead nitrate, Pb(NO3)2), pesticide stress (methomyl) and UV radiation stress. After the addition of different low concentrations of exogenous NO (10(-10)-10(-8) mol L(-1)) twice each day during cultivation, the growth of these two microalgae was obviously promoted. Results showed that NO could relieve the oxidative stresses to protect the growth of the two microalgae. For different environmental stress, there is a different optimum NO concentration for marine phytoplankton. It is speculated that the protective effect of NO is related to its antioxidant ability. PMID:23810732

  11. Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Li Xu

    Full Text Available Members of the plant NUCLEAR FACTOR Y (NF-Y family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola, each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14 were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12 and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14 were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12 and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14 and two NF-YC members (BnNF-YC2 and BnNF-YC3 were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides

  12. Abiotic Stress Tolerance: From Gene Discovery in Model Organisms to Crop Improvement

    Institute of Scientific and Technical Information of China (English)

    Ray Bressan; Hans Bohnert; Jian-Kang Zhu

    2009-01-01

    Productive and sustainable agriculture necessitates growing plants in sub-optimal environments with less input of precious resources such as fresh water. For a better understanding and rapid improvement of abiotic stress tolerance, it is important to link physiological and biochemical work to molecular studies in genetically tractable model organisms. With the use of several technologies for the discovery of stress tolerance genes and their appropriate alleles,transgenic approaches to improving stress tolerance in crops remarkably parallels breeding principles with a greatly expanded germplasm base and will succeed eventually.

  13. Corynebacterium pseudotuberculosis RNA-seq data from abiotic stresses.

    Science.gov (United States)

    de Sá, Pablo H C G; Veras, Adonney A O; Carneiro, Adriana R; Barúna, Rafael A; Guimarães, Luís C; Pinheiro, Kenny C; Pinto, Anne C; Soares, Siomar C; Schneider, Maria P C; Azevedo, Vasco; Silva, Artur; Ramos, Rommel T J

    2015-12-01

    Corynebacterium pseudotuberculosis causes significant loss to goat and sheep farmers because it is the causal agent of the infectious disease caseous lymphadenitis, which may lead to outcomes ranging from skin injury to animal death (Ruiz et al., 2011) [1]. This bacterium was grown under osmotic (2 M), acid (pH) and heat (50 °C) stress and under control (Normal-BHI brain heart infusion) conditions, which simulate the conditions faced by the bacteria during the infectious process. Subsequently, cDNA of each condition was sequenced by the SOLiD3 Plus platform using the RNA-Seq technique [2], [3], [4]. The data produced was processed to evaluate the differential gene expression, which is helpful to understand the adaptation mechanisms during the infection in the host. The sequencing data of all conditions are available in the European Bioinformatics Institute (EBI) repository under accession number E-MTAB-2017. PMID:26702428

  14. Corynebacterium pseudotuberculosis RNA-seq data from abiotic stresses

    Directory of Open Access Journals (Sweden)

    Pablo H.C.G. de Sá

    2015-12-01

    Full Text Available Corynebacterium pseudotuberculosis causes significant loss to goat and sheep farmers because it is the causal agent of the infectious disease caseous lymphadenitis, which may lead to outcomes ranging from skin injury to animal death (Ruiz et al., 2011 [1]. This bacterium was grown under osmotic (2 M, acid (pH and heat (50 °C stress and under control (Normal-BHI brain heart infusion conditions, which simulate the conditions faced by the bacteria during the infectious process. Subsequently, cDNA of each condition was sequenced by the SOLiD3 Plus platform using the RNA-Seq technique [2–4]. The data produced was processed to evaluate the differential gene expression, which is helpful to understand the adaptation mechanisms during the infection in the host. The sequencing data of all conditions are available in the European Bioinformatics Institute (EBI repository under accession number E-MTAB-2017.

  15. HyPRP1 Gene Suppressed by Multiple Stresses Plays a Negative Role in Abiotic Stress Tolerance in Tomato.

    Science.gov (United States)

    Li, Jinhua; Ouyang, Bo; Wang, Taotao; Luo, Zhidan; Yang, Changxian; Li, Hanxia; Sima, Wei; Zhang, Junhong; Ye, Zhibiao

    2016-01-01

    Many hybrid proline-rich protein (HyPRP) genes respond to biotic and abiotic stresses in plants, but little is known about their roles other than as putative cell-wall structural proteins. A HyPRP1 gene encodes a protein with proline-rich domain, and an eight-cysteine motif was identified from our previous microarray experiments on drought-tolerant tomato. In this study, the expression of the HyPRP1 gene in tomato was suppressed under various abiotic stresses, such as drought, high salinity, cold, heat, and oxidative stress. Transgenic functional analysis showed no obvious changes in phenotypes, but enhanced tolerance to various abiotic stresses (e.g., oxidative stress, dehydration, and salinity) was observed in RNAi transgenic plants. Interestingly, several SO2 detoxification-related enzymes, including sulfite oxidase, ferredoxins (Fds), and methionine sulfoxide reductase A (Msr A), were revealed in HyPRP1-interacting proteins identified by Yeast Two-Hybrid screening. More sulfates and transcripts of Msr A and Fds were accumulated in HyPRP1 knockdown lines when wild-type plants were exposed to SO2 gas. Our findings illustrate that the tomato HyPRP1 is a negative regulator of salt and oxidative stresses and is probably involved in sulfite metabolism. PMID:27446190

  16. HyPRP1 Gene Suppressed by Multiple Stresses Plays a Negative Role in Abiotic Stress Tolerance in Tomato

    Science.gov (United States)

    Li, Jinhua; Ouyang, Bo; Wang, Taotao; Luo, Zhidan; Yang, Changxian; Li, Hanxia; Sima, Wei; Zhang, Junhong; Ye, Zhibiao

    2016-01-01

    Many hybrid proline-rich protein (HyPRP) genes respond to biotic and abiotic stresses in plants, but little is known about their roles other than as putative cell-wall structural proteins. A HyPRP1 gene encodes a protein with proline-rich domain, and an eight-cysteine motif was identified from our previous microarray experiments on drought-tolerant tomato. In this study, the expression of the HyPRP1 gene in tomato was suppressed under various abiotic stresses, such as drought, high salinity, cold, heat, and oxidative stress. Transgenic functional analysis showed no obvious changes in phenotypes, but enhanced tolerance to various abiotic stresses (e.g., oxidative stress, dehydration, and salinity) was observed in RNAi transgenic plants. Interestingly, several SO2 detoxification-related enzymes, including sulfite oxidase, ferredoxins (Fds), and methionine sulfoxide reductase A (Msr A), were revealed in HyPRP1-interacting proteins identified by Yeast Two-Hybrid screening. More sulfates and transcripts of Msr A and Fds were accumulated in HyPRP1 knockdown lines when wild-type plants were exposed to SO2 gas. Our findings illustrate that the tomato HyPRP1 is a negative regulator of salt and oxidative stresses and is probably involved in sulfite metabolism. PMID:27446190

  17. Identification of Festuca arundinacea Schreb Cat1 Catalase Gene and Analysis of its Expression Under Abiotic Stresses

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Abiotic stresses, such as drought, high salinity, and cold/freezing, lead plants to produce excess reactive oxygen species. Catalase, a unique hydrogen peroxide-scavenging enzyme, plays a very important role in plants. To characterize the catalase involved in plant response to abiotic stresses, we constructed a cDNA library from 4 ℃-treated Festuca arundinacea Schreb seedlings and isolated a catalase gene from this library.The cDNA (FaCat1, 1 735 bp) contained an open reading frame of 1 479 bp. BLAST analysis indicated that the deduced amino acid sequence showed 96% identity with that from wheat TaCat1 and 87% identity with that from maize ZmCat2. Northern blotting analysis showed an obvious increase of FaCat1 transcripts in leaves in contrast with roots. Time-course analysis of the expression of FaCat1 in F. arundinacea leaves showed that FaCat1 expression was upregulated in cold- and salt-stressed leaves, with the FaCat1 transcripts accumulating mostly at 4 or 2 h after cold or salt stress, respectively. No significant changes in FaCat1 transcription were observed in dried leaves and inhibition of FaCat1 transcription was found in abscisic acid (ABA)-treated leaves,indicating that the FaCat1 gene is differentially expressed during cold, high salt, drought, and ABA treatment in F. arundinacea leaves.

  18. Impact of biotic and abiotic stresses on the competitive ability of multiple herbicide resistant wild oat (Avena fatua.

    Directory of Open Access Journals (Sweden)

    Erik A Lehnhoff

    Full Text Available Ecological theory predicts that fitness costs of herbicide resistance should lead to the reduced relative abundance of resistant populations upon the cessation of herbicide use. This greenhouse research investigated the potential fitness costs of two multiple herbicide resistant (MHR wild oat (Avena fatua populations, an economically important weed that affects cereal and pulse crop production in the Northern Great Plains of North America. We compared the competitive ability of two MHR and two herbicide susceptible (HS A. fatua populations along a gradient of biotic and abiotic stresses The biotic stress was imposed by three levels of wheat (Triticum aestivum competition (0, 4, and 8 individuals pot(-1 and an abiotic stress by three nitrogen (N fertilization rates (0, 50 and 100 kg N ha(-1. Data were analyzed with linear mixed-effects models and results showed that the biomass of all A. fatua populations decreased with increasing T. aestivum competition at all N rates. Similarly, A. fatua relative growth rate (RGR decreased with increasing T. aestivum competition at the medium and high N rates but there was no response with 0 N. There were no differences between the levels of biomass or RGR of HS and MHR populations in response to T. aestivum competition. Overall, the results indicate that MHR does not confer growth-related fitness costs in these A. fatua populations, and that their relative abundance will not be diminished with respect to HS populations in the absence of herbicide treatment.

  19. Impact of biotic and abiotic stresses on the competitive ability of multiple herbicide resistant wild oat (Avena fatua).

    Science.gov (United States)

    Lehnhoff, Erik A; Keith, Barbara K; Dyer, William E; Menalled, Fabian D

    2013-01-01

    Ecological theory predicts that fitness costs of herbicide resistance should lead to the reduced relative abundance of resistant populations upon the cessation of herbicide use. This greenhouse research investigated the potential fitness costs of two multiple herbicide resistant (MHR) wild oat (Avena fatua) populations, an economically important weed that affects cereal and pulse crop production in the Northern Great Plains of North America. We compared the competitive ability of two MHR and two herbicide susceptible (HS) A. fatua populations along a gradient of biotic and abiotic stresses The biotic stress was imposed by three levels of wheat (Triticum aestivum) competition (0, 4, and 8 individuals pot(-1)) and an abiotic stress by three nitrogen (N) fertilization rates (0, 50 and 100 kg N ha(-1)). Data were analyzed with linear mixed-effects models and results showed that the biomass of all A. fatua populations decreased with increasing T. aestivum competition at all N rates. Similarly, A. fatua relative growth rate (RGR) decreased with increasing T. aestivum competition at the medium and high N rates but there was no response with 0 N. There were no differences between the levels of biomass or RGR of HS and MHR populations in response to T. aestivum competition. Overall, the results indicate that MHR does not confer growth-related fitness costs in these A. fatua populations, and that their relative abundance will not be diminished with respect to HS populations in the absence of herbicide treatment.

  20. Grapevine NAC1 transcription factor as a convergent node in developmental processes, abiotic stresses, and necrotrophic/biotrophic pathogen tolerance.

    Science.gov (United States)

    Le Hénanff, Gaëlle; Profizi, Camille; Courteaux, Barbara; Rabenoelina, Fanja; Gérard, Clémentine; Clément, Christophe; Baillieul, Fabienne; Cordelier, Sylvain; Dhondt-Cordelier, Sandrine

    2013-11-01

    Transcription factors of the NAC family are known to be involved in various developmental processes and in response to environmental stresses. Whereas NAC genes have been widely studied in response to abiotic stresses, little is known about their role in response to biotic stresses, especially in crops. Here, the first characterization of a Vitis vinifera L. NAC member, named VvNAC1, and involved in organ development and defence towards pathogens is reported. Expression profile analysis of VvNAC1 showed that its expression is closely associated with later stages of leaf, flower, and berry development, suggesting a role in plant senescence. Moreover, VvNAC1 expression is stimulated in Botrytis cinerea- or microbe-associated molecular pattern (MAMP)-infected berries or leaves. Furthermore, cold, wounding, and defence-related hormones such as salicylic acid, methyl jasmonate, ethylene, and abscisic acid are all able to induce VvNAC1 expression in grapevine leaves. VvNAC1-overexpressing Arabidopsis plants exhibit enhanced tolerance to osmotic, salt, and cold stresses and to B. cinerea and Hyaloperonospora arabidopsidis pathogens. These plants present a modified pattern of defence gene markers (AtPR-1, AtPDF1.2, and AtVSP1) after stress application, suggesting that VvNAC1 is an important regulatory component of the plant signalling defence cascade. Collectively, these results provide evidence that VvNAC1 could represent a node of convergence regulating grapevine development and stress responses, including defence against necrotrophic and biotrophic pathogens.

  1. Expression Patterns of ERF Genes Underlying Abiotic Stresses in Di-Haploid Populus simonii × P. nigra

    Directory of Open Access Journals (Sweden)

    Shengji Wang

    2014-01-01

    Full Text Available 176 ERF genes from Populus were identified by bioinformatics analysis, 13 of these in di-haploid Populus simonii × P. nigra were investigate by real-time RT-PCR, the results demonstrated that 13 ERF genes were highly responsive to salt stress, drought stress and ABA treatment, and all were expressed in root, stem, and leaf tissues, whereas their expression levels were markedly different in the various tissues. In roots, PthERF99, 110, 119, and 168 were primarily downregulated under drought and ABA treatment but were specifically upregulated under high salt condition. Interestingly, in poplar stems, all ERF genes showed the similar trends in expression in response to NaCl stress, drought stress, and ABA treatment, indicating that they may not play either specific or unique roles in stems in abiotic stress responses. In poplar leaves, PthERF168 was highly induced by ABA treatment, but was suppressed by high salinity and drought stresses, implying that PthERF168 participated in the ABA signaling pathway. The results of this study indicated that ERF genes could play essential but distinct roles in various plant tissues in response to different environment cues and hormonal treatment.

  2. The influence of Plant Growth Promoting Rhizobacteria (PGPR on the reduction of abiotic stresses in crops

    Directory of Open Access Journals (Sweden)

    Omid Alizadeh

    2011-12-01

    Full Text Available Plants are always subjected to biotic and abiotic stresses in the environment which haveinfluences on the growth and development of the plants. Beneficial free-living soil bacteria are usuallyreferred as Plant-Growth Promoting Rhizobacteria or PGPR. Different plant growth-promotingRhizosphere bacteria, including associative bacteria such as: Azospirillum, Bacillus, Pseudomonas andEnterobacter group have been used for their beneficial influences on plants. Typically, PGPRs areassociated with plants root and augment plant productivity and immunity; however, recent worksshowed that PGPRs not have just induced the systemic tolerance to abiotic stress such as salt anddrought, but also they have increased the nutrient uptake from soils, and as a result the hazardousaccumulation of nitrates and phosphates in the agricultural soils can be reduced by usage of them.

  3. Genetically engineered Rice with transcription factor DREB genes for abiotic stress tolerance(abstract)

    International Nuclear Information System (INIS)

    Water stress (drought and Salinity) is the most severe limitation to rice productivity. Several breeding approaches (MAS, QTL) applied to suitable genotypes are in place at IRRI and elsewhere. Phenotyping of water stress tolerance is in progress with potential predictability. Dr. Shinozaki's group has cloned a number of transcription factor genes, which have been shown to work in Arabidopsis to achieve drought, cold, and salinity tolerant plants. None of these genes have as yet displayed their potential functioning in rice. Genetic engineering aims at cross talk between different stress signaling pathways leading to stress tolerance. Osmotic Adjustment (OA) is an effective component of abiotic stress (drought and salinity) tolerance in many plants including rice. When plant experiences water stress, OA contributes to turgor maintenance of both shoots and roots. Conventional breeding could not achieve the OA in rice excepting a few rice cultivars, which are partially adapted to water-stress conditions. Several stress-related genes have now been cloned and transferred in to enhance the osmolytes and some transgenic lines showed increased tolerance to osmotic stress. A few strategies could be effectively deployed for a better understanding of water-stress tolerance in rice and to develop transgenic rice, which can survive for a critical period of water-stress conditions: 1) Switching on of transcription factor regulating the expression of several genes related to abiotic stress, 2) Use of a suitable stress inducible promoter driving the target gene for an efficient and directed expression in plants, 3) Understanding of phenotyping and GxE in a given environment, 4) Selection of a few adaptive rice cultivars suitable in drought/salinity prone areas, 5) Microarray, proteomics, QTL and MAS may expedite the cloning and characterizing the stress induced genes, and 6) Finally, the efficient transformation system for generating a large number of transgenic rice of different

  4. Assessing the effects of abiotic stress and livestock grazing disturbance on an alpine grassland with CSR model

    Science.gov (United States)

    Wang, Jun; Luo, Peng; Mou, Chengxiang; Yang, Hao; Mo, Li; Luo, Chuan; Kattge, Jens

    2016-04-01

    How the abiotic factors represented by cold environment and biotic factors represented by livestock grazing will affect the vegetation structure of alpine grassland is a core issue in understanding the cause of biodiversity change on Tibetan Plateau. Past studies on changes of floristic composition, growth forms did not adequately answer question. Given the fact that the response of plant to environment change depend on its life strategy, a synthetical method that based on plant life strategy may deepen our understanding of the mechanism. Using Grime's concept of CSR plant classification, we carried out a vegetation survey along a gradient (three levels) of graze intensity on the south-east of Tibet Plateau, in order to evaluate the role and mechanism of abiotic stress and grazing disturbance in driving plant diversity change, by analyzing the plant life strategy compositions in each of the community and by comparing the characteristic of the strategy compositions along the graze gradient. When the graze intensity was relative low, the dominant plant life strategy gathered in the stress tolerance corner, which conformed the theory of environmental filter, indicating that the ideal top plant community may be dominated by the species with stress tolerant strategy. We also found that the response of strategy dominance to graze intensity increase is positively correlated with the competitive capacity (R 2=0.671; PCSR plant strategy be a useful tool to evaluate the effects of abiotic and biotic factors on plant community assembly of alpine grassland, which may contribute to predict the impacts of climate change and human activity on alpine grassland plant diversity and ecosystem service function related.

  5. Silicon, the silver bullet for mitigating biotic and abiotic stress, and improving grain quality, in rice?

    OpenAIRE

    Meharg, Caroline; Meharg, Andrew A.

    2015-01-01

    Adequate silicon fertilization greatly boosts rice yield and mitigates biotic and abiotic stress, and improves grain quality through lowering the content of cadmium and inorganic arsenic. This review on silicon dynamics in rice considers recent advances in our understanding of the role of silicon in rice, and the challenges of maintaining adequate silicon fertility within rice paddy systems. Silicon is increasingly considered as an element required for optimal plant performance, particularly ...

  6. Moderate abiotic stresses increase rhizome growth and outgrowth of axillary buds in Alstroemeria cultured in vitro

    OpenAIRE

    Pumisutapon, P.; Visser, R. G. F.; Klerk, de, L.A.

    2012-01-01

    Alstroemeria is multiplied in vitro by forced outgrowth of lateral rhizomes from rhizome explants. The multiplication rate is very low because of strong apical dominance and poor rhizome growth. We report here that moderate abiotic stresses stimulate both rhizome growth and outgrowth of lateral rhizomes, and accordingly increase multiplication. Rhizome explants were exposed to heat by a hot-water treatment (HWT) or by a hot-air treatment. Both increased rhizome growth when applied for 1 or 2 ...

  7. Nutrient seed priming improves abiotic stress tolerance in Zea mays L. and Glycine max L.

    OpenAIRE

    Imran, Muhammad

    2014-01-01

    Seed reserves are the primary source of mineral nutrients for early seedling development. ?Nutrient seed priming? is a technique in which seeds are soaked in nutrient solution and subsequently dried back to initial moisture content for storage. It is an efficient approach to increase seed nutrient contents along with priming effects to improve seed quality, germination speed and seedling establishment. Various abiotic stresses, such as sub-optimal temperature, drought, submergence and soil pH...

  8. Genome-wide characterization and analysis of bZIP transcription factor gene family related to abiotic stress in cassava.

    Science.gov (United States)

    Hu, Wei; Yang, Hubiao; Yan, Yan; Wei, Yunxie; Tie, Weiwei; Ding, Zehong; Zuo, Jiao; Peng, Ming; Li, Kaimian

    2016-01-01

    The basic leucine zipper (bZIP) transcription factor family plays crucial roles in various aspects of biological processes. Currently, no information is available regarding the bZIP family in the important tropical crop cassava. Herein, 77 bZIP genes were identified from cassava. Evolutionary analysis indicated that MebZIPs could be divided into 10 subfamilies, which was further supported by conserved motif and gene structure analyses. Global expression analysis suggested that MebZIPs showed similar or distinct expression patterns in different tissues between cultivated variety and wild subspecies. Transcriptome analysis of three cassava genotypes revealed that many MebZIP genes were activated by drought in the root of W14 subspecies, indicating the involvement of these genes in the strong resistance of cassava to drought. Expression analysis of selected MebZIP genes in response to osmotic, salt, cold, ABA, and H2O2 suggested that they might participate in distinct signaling pathways. Our systematic analysis of MebZIPs reveals constitutive, tissue-specific and abiotic stress-responsive candidate MebZIP genes for further functional characterization in planta, yields new insights into transcriptional regulation of MebZIP genes, and lays a foundation for understanding of bZIP-mediated abiotic stress response. PMID:26947924

  9. Overexpression of GmHsp90s, a heat shock protein 90 (Hsp90 gene family cloning from soybean, decrease damage of abiotic stresses in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Jinyan Xu

    Full Text Available Hsp90 is one of the most conserved and abundant molecular chaperones and is an essential component of the protective stress response; however, its roles in abiotic stress responses in soybean (Glycine max remain obscure. Here, 12 GmHsp90 genes from soybean were identified and found to be expressed and to function differentially under abiotic stresses. The 12 GmHsp90 genes were isolated and named GmHsp90A1-GmHsp90A6, GmHsp90B1, GmHsp90B2, GmHsp90C1.1, GmHsp90C1.2, GmHsp90C2.1 and GmHsp90C2.2 based on their characteristics and high homology to other Hsp90s according to a new nomenclature system. Quantitative real-time PCR expression data revealed that all the genes exhibited higher transcript levels in leaves and could be strongly induced under heat, osmotic and salt stress but not cold stress. Overexpression of five typical genes (GmHsp90A2, GmHsp90A4, GmHsp90B1, GmHsp90C1.1 and GmHsp90C2.1 in Arabidopsis thaliana provided useful evidences that GmHsp90 genes can decrease damage of abiotic stresses. In addition, an abnormal accumulation of proline was detected in some transgenic Arabidopsis plants suggested overexpressing GmHsp90s may affect the synthesis and response system of proline. Our work represents a systematic determination of soybean genes encoding Hsp90s, and provides useful evidence that GmHsp90 genes function differently in response to abiotic stresses and may affect the synthesis and response system of proline.

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

    Science.gov (United States)

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

    2015-01-01

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

  11. Study of a new alternative antioxidant in soybean plants subjected to abiotic stress

    International Nuclear Information System (INIS)

    We have recently, demonstrated that the induction of heme oxygenase-1 (HO-1) plays a protective role for soybean plants against oxidative stress produced by cadmium and UV-B radiation. At this moment we propose to investigate if the enzyme has the same capacity against another type of abiotic stress, such as drought, for to demonstrate that heme oxygenase acts as an enzyme of plant antioxidant defense system under several different stress situations, as occur in mammalian tissues. To carry out this objective we propose to study, in leaf, root and nodule of soybean plants, the oxidative stress generation; the behavior of classical antioxidant system; the behavior of HO-1 activity and protein and gene expression; the effect of its reaction products and inhibitors on the oxidative stress parameters; the signaling mechanism that produce HO-1 induction and the immunohistochemistry localization of the enzyme in the different plant tissues. The results obtained let us undoubtedly demonstrate the involvement of HO-1 in the antioxidant defense system in plants. This finding will allow the increase in the knowledge of the defense mechanisms in interesting economic plants for our country, such as soybean, and against drought, an abiotic stress considered one of the most important factors limiting plant performance and yield worldwide. (authors)

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

    Directory of Open Access Journals (Sweden)

    Amarjeet Singh

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

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

    OpenAIRE

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

    2014-01-01

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

  14. A wheat WRKY transcription factor TaWRKY10 confers tolerance to multiple abiotic stresses in transgenic tobacco.

    Directory of Open Access Journals (Sweden)

    Chen Wang

    Full Text Available WRKY transcription factors are reported to be involved in defense regulation, stress response and plant growth and development. However, the precise role of WRKY transcription factors in abiotic stress tolerance is not completely understood, especially in crops. In this study, we identified and cloned 10 WRKY genes from genome of wheat (Triticum aestivum L.. TaWRKY10, a gene induced by multiple stresses, was selected for further investigation. TaWRKY10 was upregulated by treatment with polyethylene glycol, NaCl, cold and H2O2. Result of Southern blot indicates that the wheat genome contains three copies of TaWRKY10. The TaWRKY10 protein is localized in the nucleus and functions as a transcriptional activator. Overexpression of TaWRKY10 in tobacco (Nicotiana tabacum L. resulted in enhanced drought and salt stress tolerance, mainly demonstrated by the transgenic plants exhibiting of increased germination rate, root length, survival rate, and relative water content under these stress conditions. Further investigation showed that transgenic plants also retained higher proline and soluble sugar contents, and lower reactive oxygen species and malonaldehyde contents. Moreover, overexpression of the TaWRKY10 regulated the expression of a series of stress related genes. Taken together, our results indicate that TaWRKY10 functions as a positive factor under drought and salt stresses by regulating the osmotic balance, ROS scavenging and transcription of stress related genes.

  15. ISOLATION OF MESOPHYLL PROTOPLASTS FROM MEDITERRANEAN WOODY PLANTS FOR THE STUDY OF DNA INTEGRITY UNDER ABIOTIC STRESS

    Directory of Open Access Journals (Sweden)

    Elena Kuzminsky

    2016-08-01

    Full Text Available Abiotic stresses have considerable negative impact on Mediterranean plant ecosystems and better comprehension of the genetic control of response and adaptation of trees to global changes is urgently needed. The Single Cell Gel Electrophoresis assay could be considered a good estimator of DNA damage in an individual eukaryotic cell. This method has been mainly employed in animal tissues, because the plant cell wall represents an obstacle for the extraction of nuclei; moreover, in Mediterranean woody species, especially in the sclerophyll plants, this procedure can be quite difficult because of the presence of sclerenchyma and hardened cells. On the other hand, these plants represent an interesting material to be studied because of the ability of these plants to tolerate abiotic stress. For instance, holm oak (Quercus ilex L. has been selected as the model plant to identify critical levels of O3 for Southern European forests. Consequently, a quantitative method for the evaluation of cell injury of leaf tissues of this species is required. Optimal conditions for high-yield nuclei isolation were obtained by using protoplast technology and a detailed description of the method is provided and discussed. White poplar (Populus alba L. was used as an internal control for protoplast isolation. Such a method has not been previously reported in newly fully developed leaves of holm oak. This method combined with Single Cell Gel Electrophoresis assay represents a new tool for testing the DNA integrity of leaf tissues in higher plants under stress conditions.

  16. Isolation of Mesophyll Protoplasts from Mediterranean Woody Plants for the Study of DNA Integrity under Abiotic Stress.

    Science.gov (United States)

    Kuzminsky, Elena; Meschini, Roberta; Terzoli, Serena; Pavani, Liliana; Silvestri, Cristian; Choury, Zineb; Scarascia-Mugnozza, Giuseppe

    2016-01-01

    Abiotic stresses have considerable negative impact on Mediterranean plant ecosystems and better comprehension of the genetic control of response and adaptation of trees to global changes is urgently needed. The single cell gel electrophoresis (SCGE) assay could be considered a good estimator of DNA damage in an individual eukaryotic cell. This method has been mainly employed in animal tissues, because the plant cell wall represents an obstacle for the extraction of nuclei; moreover, in Mediterranean woody species, especially in the sclerophyll plants, this procedure can be quite difficult because of the presence of sclerenchyma and hardened cells. On the other hand, these plants represent an interesting material to be studied because of the ability of these plants to tolerate abiotic stress. For instance, holm oak (Quercus ilex L.) has been selected as the model plant to identify critical levels of O3 for Southern European forests. Consequently, a quantitative method for the evaluation of cell injury of leaf tissues of this species is required. Optimal conditions for high-yield nuclei isolation were obtained by using protoplast technology and a detailed description of the method is provided and discussed. White poplar (Populus alba L.) was used as an internal control for protoplast isolation. Such a method has not been previously reported in newly fully developed leaves of holm oak. This method combined with SCGE assay represents a new tool for testing the DNA integrity of leaf tissues in higher plants under stress conditions.

  17. Isolation of Mesophyll Protoplasts from Mediterranean Woody Plants for the Study of DNA Integrity under Abiotic Stress.

    Science.gov (United States)

    Kuzminsky, Elena; Meschini, Roberta; Terzoli, Serena; Pavani, Liliana; Silvestri, Cristian; Choury, Zineb; Scarascia-Mugnozza, Giuseppe

    2016-01-01

    Abiotic stresses have considerable negative impact on Mediterranean plant ecosystems and better comprehension of the genetic control of response and adaptation of trees to global changes is urgently needed. The single cell gel electrophoresis (SCGE) assay could be considered a good estimator of DNA damage in an individual eukaryotic cell. This method has been mainly employed in animal tissues, because the plant cell wall represents an obstacle for the extraction of nuclei; moreover, in Mediterranean woody species, especially in the sclerophyll plants, this procedure can be quite difficult because of the presence of sclerenchyma and hardened cells. On the other hand, these plants represent an interesting material to be studied because of the ability of these plants to tolerate abiotic stress. For instance, holm oak (Quercus ilex L.) has been selected as the model plant to identify critical levels of O3 for Southern European forests. Consequently, a quantitative method for the evaluation of cell injury of leaf tissues of this species is required. Optimal conditions for high-yield nuclei isolation were obtained by using protoplast technology and a detailed description of the method is provided and discussed. White poplar (Populus alba L.) was used as an internal control for protoplast isolation. Such a method has not been previously reported in newly fully developed leaves of holm oak. This method combined with SCGE assay represents a new tool for testing the DNA integrity of leaf tissues in higher plants under stress conditions. PMID:27574524

  18. Nicotiana tabacum Tsip1-Interacting Ferredoxin 1 Affects Biotic and Abiotic Stress Resistance

    OpenAIRE

    Huh, Sung Un; Lee, In-Ju; Ham, Byung-Kook; Paek, Kyung-Hee

    2012-01-01

    Tsip1, a Zn finger protein that was isolated as a direct interactor with tobacco stress-induced 1 (Tsi1), plays an important role in both biotic and abiotic stress signaling. To further understand Tsip1 function, we searched for more Tsip1-interacting proteins by yeast two-hybrid screening using a tobacco cDNA library. Screening identified a new Tsip1-interacting protein, Nicotiana tabacum Tsip1-interacting ferredoxin 1 (NtTfd1), and binding specificity was confirmed both in vitro and in vivo...

  19. Ionomic profiling of Nicotiana langsdorffii wild-type and mutant genotypes exposed to abiotic stresses.

    Science.gov (United States)

    Ardini, Francisco; Soggia, Francesco; Abelmoschi, Maria Luisa; Magi, Emanuele; Grotti, Marco

    2013-01-01

    To provide a new insight into the response of plants to abiotic stresses, the ionomic profiles of Nicotiana langsdorffii specimens have been determined before and after exposure to toxic metals (chromium) or drought conditions. The plants were genetically transformed with the rat glucocorticoid receptor (GR) or the gene for Agrobacterium rhizogenes rolC, because these modifications are known to produce an imbalance in phytohormone equilibria and a significant change in the defence response of the plant. Elemental profiles were obtained by developing and applying analytical procedures based on inductively coupled plasma atomic emission and mass spectrometry (ICP-AES/MS). In particular, the removal of isobaric interferences affecting the determination of Cr and V by ICP-MS was accomplished by use of a dynamic reaction cell, after optimization of the relevant conditions. The combined use of ICP atomic emission and mass spectrometry enabled the determination of 29 major and trace elements (Ba, Bi, Ca, Cd, Co, Cr, Cu, Eu, Fe, Ga, K, Li, Mg, Mn, Mo, Na, P, Pb, Pt, Rb, S, Sb, Sn, Sr, Te, V, W, Y, and Zn) in different parts of the plants (roots, stems, and leaves), with high accuracy and precision. Multivariate data processing and study of element distribution patterns provided new information about the ionomic response of the target organism to chemical treatment or water stress. Genetic modification mainly affected the distribution of Bi, Cr, Mo, Na, and S, indicating that these elements were involved in biochemical processes controlled by the GR or rolC genes. Chemical stress strongly affected accumulation of several elements (Ba, Ca, Fe, Ga, K, Li, Mn, Mo, Na, P, Pb, Rb, S, Sn, Te, V, and Zn) in different ways; for Ca, Fe, K, Mn, Na, and P the effect was quite similar to that observed in other studies after treatment with other transition elements, for example Cu and Cd. The effect of water deficit was less evident, mainly consisting in a decrease of Ba, Cr, Na, and Sr

  20. In Vitro Screening for Abiotic Stress Tolerance in Potent Biocontrol and Plant Growth Promoting Strains of Pseudomonas and Bacillus spp.

    OpenAIRE

    G. Praveen Kumar; Mir Hassan Ahmed, S. K.; Suseelendra Desai; Leo Daniel Amalraj, E.; Abdul Rasul

    2014-01-01

    Plant growth promoting rhizobacteria (PGPR) has been identified as a group of microbes that are used for plant growth enhancement and biocontrol for management of plant diseases. The inconsistency in performance of these bacteria from laboratory to field conditions is compounded due to the prevailing abiotic stresses in the field. Therefore, selection of bacterial strains with tolerance to abiotic stresses would benefit the end-user by successful establishment of the strain for showing desire...

  1. Biotechnological Approaches to Study Plant Responses to Stress

    OpenAIRE

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

    2013-01-01

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

  2. Development of abiotic-stress resistant warm season trufgrasses by proton-beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Y. W.; Kim, J. Y.; Jeong, S. H. [Korea Univ., Seoul (Korea, Republic of)

    2007-04-15

    The direct use of mutation is a valuable approach to generate genetic variation in crop species by altering agronomically useful major traits. The proton beam, as a mutagen, was applied to improve resistance traits of Zoysia grass under various abiotic stresses. Proton beam was irradiated to mature dry seeds of Zenith (Zoysia grass), which is well-adapted to Korean climate, using a proton- accelerator with seven different doses (50, 100, 150, 200, 250, 300, 400 Gy). Individual seedling of M1 plant was transplanted from the seed bed and allowed to reach appropriate plant mass. Clones that showed superior growth were chosen and transplanted to pots for further clone propagation and field evaluation. Growth characteristics of turfgrass, such as plant height, leaf length, leaf width, number of tiller were evaluated ninety days after sowing. Although large variation within each dose, noticeable differences were found among different irradiated doses. Most of the mutant clones derived from the irradiation treatment showed more vigorous growth than the control plants. RAPD (Random Amplified Polymorphic DNA) and AFLP (Amplified Fragment Length Polymorphism) methods were conducted to analyze genomic variations associated with proton beam irradiation. In order to establish selection criteria for selection of salt-stress resistance plants, an in vitro method that is able to select salt-stress resistant mutants in liquid media without ambient disturbances. Total 647 predominance clones that were considered as abiotic stress resistant mutants were transplanted to the field for further evaluation.

  3. Genome-wide analysis of heat shock proteins in C4 model, foxtail millet identifies potential candidates for crop improvement under abiotic stress.

    Science.gov (United States)

    Singh, Roshan Kumar; Jaishankar, Jananee; Muthamilarasan, Mehanathan; Shweta, Shweta; Dangi, Anand; Prasad, Manoj

    2016-01-01

    Heat shock proteins (HSPs) perform significant roles in conferring abiotic stress tolerance to crop plants. In view of this, HSPs and their encoding genes were extensively characterized in several plant species; however, understanding their structure, organization, evolution and expression profiling in a naturally stress tolerant crop is necessary to delineate their precise roles in stress-responsive molecular machinery. In this context, the present study has been performed in C4 panicoid model, foxtail millet, which resulted in identification of 20, 9, 27, 20 and 37 genes belonging to SiHSP100, SiHSP90, SiHSP70, SiHSP60 and SisHSP families, respectively. Comprehensive in silico characterization of these genes followed by their expression profiling in response to dehydration, heat, salinity and cold stresses in foxtail millet cultivars contrastingly differing in stress tolerance revealed significant upregulation of several genes in tolerant cultivar. SisHSP-27 showed substantial higher expression in response to heat stress in tolerant cultivar, and its over-expression in yeast system conferred tolerance to several abiotic stresses. Methylation analysis of SiHSP genes suggested that, in susceptible cultivar, higher levels of methylation might be the reason for reduced expression of these genes during stress. Altogether, the study provides novel clues on the role of HSPs in conferring stress tolerance. PMID:27586959

  4. Genome-wide analysis of heat shock proteins in C4 model, foxtail millet identifies potential candidates for crop improvement under abiotic stress

    Science.gov (United States)

    Singh, Roshan Kumar; Jaishankar, Jananee; Muthamilarasan, Mehanathan; Shweta, Shweta; Dangi, Anand; Prasad, Manoj

    2016-01-01

    Heat shock proteins (HSPs) perform significant roles in conferring abiotic stress tolerance to crop plants. In view of this, HSPs and their encoding genes were extensively characterized in several plant species; however, understanding their structure, organization, evolution and expression profiling in a naturally stress tolerant crop is necessary to delineate their precise roles in stress-responsive molecular machinery. In this context, the present study has been performed in C4 panicoid model, foxtail millet, which resulted in identification of 20, 9, 27, 20 and 37 genes belonging to SiHSP100, SiHSP90, SiHSP70, SiHSP60 and SisHSP families, respectively. Comprehensive in silico characterization of these genes followed by their expression profiling in response to dehydration, heat, salinity and cold stresses in foxtail millet cultivars contrastingly differing in stress tolerance revealed significant upregulation of several genes in tolerant cultivar. SisHSP-27 showed substantial higher expression in response to heat stress in tolerant cultivar, and its over-expression in yeast system conferred tolerance to several abiotic stresses. Methylation analysis of SiHSP genes suggested that, in susceptible cultivar, higher levels of methylation might be the reason for reduced expression of these genes during stress. Altogether, the study provides novel clues on the role of HSPs in conferring stress tolerance. PMID:27586959

  5. Differential Regulation of Genes Coding for Organelle and Cytosolic ClpATPases under Biotic and Abiotic Stresses in Wheat

    Science.gov (United States)

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

    2016-01-01

    A sub-group of class I Caseinolytic proteases (Clps) function as molecular chaperone and confer thermotolerance to plants. We identified class I Clp family consisting of five ClpB/HSP100, two ClpC, and two ClpD genes from bread wheat. Phylogenetic analysis showed that these genes were highly conserved across grass genomes. Subcellular localization prediction revealed that TaClpC and TaClpD subgroup proteins and TaClpB1 proteins are potentially targeted to chloroplast, while TaClpB5 to mitochondria, and TaClpB2, TaClpB3, and TaClpB4 to cytoplasm. Spatio-temporal expression pattern analysis revealed that four TaClpB and TaClpD2 genes are expressed in majority of all tissues and developmental stages of wheat. Real-time RT-PCR analysis of expression levels of Clp genes in seven wheat genotypes under different abiotic stresses revealed that genes coding for the cytosolic Clps namely TaClpB2 and TaClpB3 were upregulated under heat, salt and oxidative stress but were downregulated by cold stress in most genotypes. In contrast, genes coding for the chloroplastic Clps TaClpC1, TaClpC2, and TaClpD1 genes were significantly upregulated by mainly by cold stress in most genotypes, while TaClpD2 gene was upregulated >2 fold by salt stress in DBW16. The TaClpB5 gene coding for mitochondrial Clp was upregulated in all genotypes under heat, salt and oxidative stresses. In addition, we found that biotic stresses also upregulated TaClpB4 and TaClpD1. Among biotic stresses, Tilletia caries induced TaClpB2, TaClpB3, TaClpC1, and TaClpD1. Differential expression pattern under different abiotic and biotic stresses and predicted differential cellular localization of Clps suggest their non-redundant organelle and stress-specific roles. Our results also suggest the potential role of Clps in cold, salt and biotic stress responses in addition to the previously established role in thermotolerance of wheat. PMID:27446158

  6. Differential Regulation of Genes Coding for Organelle and Cytosolic ClpATPases under Biotic and Abiotic Stresses in Wheat.

    Science.gov (United States)

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

    2016-01-01

    A sub-group of class I Caseinolytic proteases (Clps) function as molecular chaperone and confer thermotolerance to plants. We identified class I Clp family consisting of five ClpB/HSP100, two ClpC, and two ClpD genes from bread wheat. Phylogenetic analysis showed that these genes were highly conserved across grass genomes. Subcellular localization prediction revealed that TaClpC and TaClpD subgroup proteins and TaClpB1 proteins are potentially targeted to chloroplast, while TaClpB5 to mitochondria, and TaClpB2, TaClpB3, and TaClpB4 to cytoplasm. Spatio-temporal expression pattern analysis revealed that four TaClpB and TaClpD2 genes are expressed in majority of all tissues and developmental stages of wheat. Real-time RT-PCR analysis of expression levels of Clp genes in seven wheat genotypes under different abiotic stresses revealed that genes coding for the cytosolic Clps namely TaClpB2 and TaClpB3 were upregulated under heat, salt and oxidative stress but were downregulated by cold stress in most genotypes. In contrast, genes coding for the chloroplastic Clps TaClpC1, TaClpC2, and TaClpD1 genes were significantly upregulated by mainly by cold stress in most genotypes, while TaClpD2 gene was upregulated >2 fold by salt stress in DBW16. The TaClpB5 gene coding for mitochondrial Clp was upregulated in all genotypes under heat, salt and oxidative stresses. In addition, we found that biotic stresses also upregulated TaClpB4 and TaClpD1. Among biotic stresses, Tilletia caries induced TaClpB2, TaClpB3, TaClpC1, and TaClpD1. Differential expression pattern under different abiotic and biotic stresses and predicted differential cellular localization of Clps suggest their non-redundant organelle and stress-specific roles. Our results also suggest the potential role of Clps in cold, salt and biotic stress responses in addition to the previously established role in thermotolerance of wheat. PMID:27446158

  7. Brassinosteroids make plant life easier under abiotic stresses mainly by modulating major components of antioxidant defense system

    Directory of Open Access Journals (Sweden)

    Bojjam V. Vardhini

    2015-01-01

    Full Text Available Various abiotic stress factors significantly contribute to major worldwide-losses in crop productivity by mainly impacting plant’s stress tolerance/adaptive capacity. The latter is largely governed by the efficiency of antioxidant defense system for the metabolism of elevated reactive oxygen species (ROS, caused by different abiotic stresses. Plant antioxidant defense system includes both enzymatic (such as superoxide dismutase, SOD, E.C. 1.15.1.1; catalase, CAT, E.C. 1.11.1.6; glutathione reductase, GR, E.C. 1.6.4.2; peroxidase, POD, E.C. 1.11.1.7; ascorbate peroxidase, APX, E.C. 1.11.1.11; guaiacol peroxidase, GPX, E.C. 1.11.1.7 and non-enzymatic (such as ascorbic acid, AsA; glutathione, GSH; tocopherols; phenolics, proline etc. components. Research reports on the status of various abiotic stresses and their impact on plant growth, development and productivity are extensive. However, least information is available on sustainable strategies for the mitigation of abiotic stress-mediated major consequences in plants. Brassinosteroids (BRs are a novel group of phytohormones with significant growth promoting nature. BRs are considered as growth regulators with pleiotropic effects, as they influence diverse physiological processes like growth, germination of seeds, rhizogenesis, senescence etc. and also confer abiotic stress resistance in plants. In the light of recent reports this paper: (a overviews major abiotic stresses and plant antioxidant defense system, (b introduces BRs and highlights their significance in general plant growth and development, and (c appraises recent literature available on BRs mediated modulation of various components of antioxidant defense system in plants under major abiotic stresses including metals/metalloids, drought, salinity, and temperature regimes. The outcome can be significant in devising future research in the current direction.

  8. The SsDREB Transcription Factor from the Succulent Halophyte Suaeda salsa Enhances Abiotic Stress Tolerance in Transgenic Tobacco

    Directory of Open Access Journals (Sweden)

    Xu Zhang

    2015-01-01

    Full Text Available Dehydration-responsive element-binding (DREB transcription factor (TF plays a key role for abiotic stress tolerance in plants. In this study, a novel cDNA encoding DREB transcription factor, designated SsDREB, was isolated from succulent halophyte Suaeda salsa. This protein was classified in the A-6 group of DREB subfamily based on multiple sequence alignments and phylogenetic characterization. Yeast one-hybrid assays showed that SsDREB protein specifically binds to the DRE sequence and could activate the expression of reporter genes in yeast, suggesting that the SsDREB protein was a CBF/DREB transcription factor. Real-time RT-PCR showed that SsDREB was significantly induced under salinity and drought stress. Overexpression of SsDREB cDNA in transgenic tobacco plants exhibited an improved salt and drought stress tolerance in comparison to the nontransformed controls. The transgenic plants revealed better growth, higher chlorophyll content, and net photosynthesis rate, as well as higher level of proline and soluble sugars. The semiquantitative PCR of transgenics showed higher expression of stress-responsive genes. These data suggest that the SsDREB transcription factor is involved in the regulation of salt stress tolerance in tobacco by the activation of different downstream gene expression.

  9. The SsDREB Transcription Factor from the Succulent Halophyte Suaeda salsa Enhances Abiotic Stress Tolerance in Transgenic Tobacco.

    Science.gov (United States)

    Zhang, Xu; Liu, Xiaoxue; Wu, Lei; Yu, Guihong; Wang, Xiue; Ma, Hongxiang

    2015-01-01

    Dehydration-responsive element-binding (DREB) transcription factor (TF) plays a key role for abiotic stress tolerance in plants. In this study, a novel cDNA encoding DREB transcription factor, designated SsDREB, was isolated from succulent halophyte Suaeda salsa. This protein was classified in the A-6 group of DREB subfamily based on multiple sequence alignments and phylogenetic characterization. Yeast one-hybrid assays showed that SsDREB protein specifically binds to the DRE sequence and could activate the expression of reporter genes in yeast, suggesting that the SsDREB protein was a CBF/DREB transcription factor. Real-time RT-PCR showed that SsDREB was significantly induced under salinity and drought stress. Overexpression of SsDREB cDNA in transgenic tobacco plants exhibited an improved salt and drought stress tolerance in comparison to the nontransformed controls. The transgenic plants revealed better growth, higher chlorophyll content, and net photosynthesis rate, as well as higher level of proline and soluble sugars. The semiquantitative PCR of transgenics showed higher expression of stress-responsive genes. These data suggest that the SsDREB transcription factor is involved in the regulation of salt stress tolerance in tobacco by the activation of different downstream gene expression. PMID:26504772

  10. QTLs for Tolerance of Drought and Breeding for Tolerance of Abiotic and Biotic Stress: An Integrated Approach

    OpenAIRE

    Shalabh Dixit; B Emma Huang; Ma Teresa Sta Cruz; Maturan, Paul T; Jhon Christian E Ontoy; Arvind Kumar

    2014-01-01

    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-tole...

  11. Protein Synthesis Inhibition Activity by Strawberry Tissue Protein Extracts during Plant Life Cycle and under Biotic and Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    Walther Faedi

    2013-07-01

    Full Text Available Ribosome-inactivating proteins (RIPs, enzymes that are widely distributed in the plant kingdom, inhibit protein synthesis by depurinating rRNA and many other polynucleotidic substrates. Although RIPs show antiviral, antifungal, and insecticidal activities, their biological and physiological roles are not completely understood. Additionally, it has been described that RIP expression is augmented under stressful conditions. In this study, we evaluated protein synthesis inhibition activity in partially purified basic proteins (hereafter referred to as RIP activity from tissue extracts of Fragaria × ananassa (strawberry cultivars with low (Dora and high (Record tolerance to root pathogens and fructification stress. Association between the presence of RIP activity and the crop management (organic or integrated soil, growth stage (quiescence, flowering, and fructification, and exogenous stress (drought were investigated. RIP activity was found in every tissue tested (roots, rhizomes, leaves, buds, flowers, and fruits and under each tested condition. However, significant differences in RIP distribution were observed depending on the soil and growth stage, and an increase in RIP activity was found in the leaves of drought-stressed plants. These results suggest that RIP expression and activity could represent a response mechanism against biotic and abiotic stresses and could be a useful tool in selecting stress-resistant strawberry genotypes.

  12. A single gene all3940 (Dps) overexpression in Anabaena sp. PCC 7120 confers multiple abiotic stress tolerance via proteomic alterations.

    Science.gov (United States)

    Narayan, Om Prakash; Kumari, Nidhi; Bhargava, Poonam; Rajaram, Hema; Rai, Lal Chand

    2016-01-01

    DNA-binding proteins (Dps) induced during starvation play an important role in gene regulation and maintaining homeostasis in bacteria. The nitrogen-fixing cyanobacterium, Anabaena PCC7120, has four genes annotated as coding for Dps; however, the information on their physiological roles is limiting. One of the genes coding for Dps, 'all3940' was found to be induced under different abiotic stresses in Anabaena and upon overexpression enhanced the tolerance of Anabaena to a multitude of stresses, which included salinity, heat, heavy metals, pesticide, and nutrient starvation. On the other hand, mutation in the gene resulted in decreased growth of Anabaena. The modulation in the levels of All3940 in Anabaena, achieved either by overexpression of the protein or mutation of the gene, resulted in changes in the proteome, which correlated well with the physiological changes observed. Proteins required for varied physiological activities, such as photosynthesis, carbon-metabolism, oxidative stress alleviation, exhibited change in protein profile upon modulation of All3940 levels in Anabaena. This suggested a direct or an indirect effect of All3940 on the expression of the above stress-responsive proteins, thereby enhancing tolerance in Anabaena PCC7120. Thus, All3940, though categorized as a Dps, is possibly a general stress protein having a global role in regulating tolerance to multitude of stresses in Anabaena.

  13. Arabidopsis thaliana glyoxalase 2-1 is required during abiotic stress but is not essential under normal plant growth.

    Directory of Open Access Journals (Sweden)

    Sriram Devanathan

    Full Text Available The glyoxalase pathway, which consists of the two enzymes, GLYOXALASE 1 (GLX 1 (E.C.: 4.4.1.5 and 2 (E.C.3.1.2.6, has a vital role in chemical detoxification. In Arabidopsis thaliana there are at least four different isoforms of glyoxalase 2, two of which, GLX2-1 and GLX2-4 have not been characterized in detail. Here, the functional role of Arabidopsis thaliana GLX2-1 is investigated. Glx2-1 loss-of-function mutants and plants that constitutively over-express GLX2-1 resemble wild-type plants under normal growth conditions. Insilico analysis of publicly available microarray datasets with ATTEDII, Mapman and Genevestigator indicate potential role(s in stress response and acclimation. Results presented here demonstrate that GLX2-1 gene expression is up-regulated in wild type Arabidopsis thaliana by salt and anoxia stress, and by excess L-Threonine. Additionally, a mutation in GLX2-1 inhibits growth and survival during abiotic stresses. Metabolic profiling studies show alterations in the levels of sugars and amino acids during threonine stress in the plants. Elevated levels of polyamines, which are known stress markers, are also observed. Overall our results suggest that Arabidopsis thaliana GLX2-1 is not essential during normal plant life, but is required during specific stress conditions.

  14. Identification and expression of C2H2 transcription factor genes in Carica papaya under abiotic and biotic stresses.

    Science.gov (United States)

    Jiang, Ling; Pan, Lin-jie

    2012-06-01

    C2H2 proteins belong to a group of transcription factors (TFs) existing as a superfamily that plays important roles in defense responses and various other physiological processes in plants. The present study aimed to screen for and identify C2H2 proteins associated with defense responses to abiotic and biotic stresses in Carica papaya L. Data were collected for 47,483 papaya-expressed sequence tags (ESTs). The full-length cDNA nucleotide sequences of 87 C2H2 proteins were predicated by BioEdit. All 91 C2H2 proteins were aligned, and a phylogenetic tree was constructed using DNAman. The expression levels of 42 C2H2 were analyzed under conditions of salt stress by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Methyl jasmonate treatment rapidly upregulated ZF(23.4) and ZF(30,912.1) by 18.6- and 21.7-fold, respectively. ZF(1.3), ZF(138.44), ZF(94.49), ZF(29.160), and ZF(20.206) were found to be downregulated after low temperature treatment at very significant levels (p papaya ringspot virus pathogen. ZF(30,912.1) was subcellularly localized in the nucleus by a transgenic fusion of pBS-ZF(30,912.1)-GFP into the protoplast of papaya. The results of the present study showed that ZF(30,912.1) could be an important TF that mediates responses to abiotic and biotic stresses in papaya.

  15. Effects of abiotic stress on physiological plasticity and water use of Setaria viridis (L.).

    Science.gov (United States)

    Saha, Prasenjit; Sade, Nir; Arzani, Ahmad; Rubio Wilhelmi, Maria Del Mar; Coe, Kevin M; Li, Bosheng; Blumwald, Eduardo

    2016-10-01

    The emerging model Setaria viridis with its C4 photosynthesis and adaptation to hot and dry locations is a promising system to investigate water use and abiotic stress tolerance. We investigated the physiological plasticity of six S. viridis natural accessions that originated from different regions of the world under normal conditions and conditions of water-deficit stress and high temperatures. Accessions Zha-1, A10.1 and Ula-1 showed significantly higher leaf water potential (Ψleaf), photosynthesis (A), transpiration (E), and stomatal conductance (gs) rates compared to Ast-1, Aba-1 and Sha-1 when grown under stress conditions. Expression analysis of genes associated with C4 photosynthesis, aquaporins, ABA biosynthesis and signaling including genes involved in stress revealed an increased sensitivity of Ast-1, Aba-1 and Sha-1 to stresses. Correlation analysis of gene expression data with physiological and biochemical changes characterized A10.1 and Ast-1 as two extreme tolerant and sensitive accessions originated from United States and Azerbaijan under water-deficit and heat stress, respectively. Although preliminary, our study demonstrated the plasticity of S. viridis accessions under stress, and allows the identification of tolerant and sensitive accessions that could be use to study the mechanisms associated with stress tolerance and to characterize of the regulatory networks involved in C4 grasses. PMID:27593471

  16. Increase of starch accumulation in the duckweed Lemna minor under abiotic stress

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    K. SOWJANYA SREE

    2014-06-01

    Full Text Available Abiotic stresses often result in suppression of photosynthesis and plant growth. Using the duckweed species Lemna minor and subjecting these plants to abiotic stress viz., (1 application of heavy metals, (2 application of salt (NaCl, and (3 lack of phosphate, we showed that photosynthesis was inhibited to a lesser degree than plant growth. This became evident by detecting the accumulation of starch under these conditions: (1 Cadmium ions and other heavy metals induced the accumulation of starch after 4 days of treatment at concentrations when growth was almost completely suppressed (e. g. 80 %. (2 Application of NaCl at a concentration of 150 mM also resulted in accumulation of starch but the highest level could be observed only after 7 days. (3 Depletion of phosphate in the growth medium had similar effects leading to starch accumulation after 14 days of treatment. Starch can accumulate to approximately 50% of dry mass under the three different conditions. We suggest the following common molecular mechanism: The stress factor suppresses growth more effectively than photosynthesis. The resulting surplus of carbohydrates is then stored as starch. This hypothesis has biotechnological relevance since stressors may be applied for increasing starch accumulation in duckweed and thus could be used to optimize bioethanol production from this aquatic crop.

  17. Function of S-nitrosoglutathione reductase (GSNOR) in plant development and under biotic/abiotic stress

    Science.gov (United States)

    Leterrier, Marina; Chaki, Mounira; Airaki, Morad; Valderrama, Raquel; Palma, José M; Barroso, Juan B

    2011-01-01

    During the last decade, it was established that the class III alcohol dehydrogenase (ADH3) enzyme, also known as glutathione-dependent formaldehyde dehydrogenase (FALDH; EC 1.2.1.1), catalyzes the NADH-dependent reduction of S-nitrosoglutathione (GSNO) and therefore was also designated as GSNO reductase. This finding has opened new aspects in the metabolism of nitric oxide (NO) and NO-derived molecules where GSNO is a key component. In this article, current knowledge of the involvement and potential function of this enzyme during plant development and under biotic/abiotic stress is briefly reviewed. PMID:21543898

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

    OpenAIRE

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

    2015-01-01

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

  19. 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.

  20. Improved tolerance to various abiotic stresses in transgenic sweet potato (Ipomoea batatas expressing spinach betaine aldehyde dehydrogenase.

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    Weijuan Fan

    Full Text Available Abiotic stresses are critical delimiters for the increased productivity and cultivation expansion of sweet potato (Ipomoea batatas, a root crop with worldwide importance. The increased production of glycine betaine (GB improves plant tolerance to various abiotic stresses without strong phenotypic changes, providing a feasible approach to improve stable yield production under unfavorable conditions. The gene encoding betaine aldehyde dehydrogenase (BADH is involved in the biosynthesis of GB in plants, and the accumulation of GB by the heterologous overexpression of BADH improves abiotic stress tolerance in plants. This study is to improve sweet potato, a GB accumulator, resistant to multiple abiotic stresses by promoted GB biosynthesis. A chloroplastic BADH gene from Spinacia oleracea (SoBADH was introduced into the sweet potato cultivar Sushu-2 via Agrobacterium-mediated transformation. The overexpression of SoBADH in the transgenic sweet potato improved tolerance to various abiotic stresses, including salt, oxidative stress, and low temperature. The increased BADH activity and GB accumulation in the transgenic plant lines under normal and multiple environmental stresses resulted in increased protection against cell damage through the maintenance of cell membrane integrity, stronger photosynthetic activity, reduced reactive oxygen species (ROS production, and induction or activation of ROS scavenging by the increased activity of free radical-scavenging enzymes. The increased proline accumulation and systemic upregulation of many ROS-scavenging genes in stress-treated transgenic plants also indicated that GB accumulation might stimulate the ROS-scavenging system and proline biosynthesis via an integrative mechanism. This study demonstrates that the enhancement of GB biosynthesis in sweet potato is an effective and feasible approach to improve its tolerance to multiple abiotic stresses without causing phenotypic defects. This strategy for trait

  1. Overexpression of small heat shock protein LimHSP16.45 in Arabidopsis enhances tolerance to abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Changjun Mu

    Full Text Available Small heat shock proteins (smHSPs play important and extensive roles in plant defenses against abiotic stresses. We cloned a gene for a smHSP from the David Lily (Lilium davidii (E. H. Wilson Raffill var. Willmottiae, which we named LimHSP16.45 based on its protein molecular weight. Its expression was induced by many kinds of abiotic stresses in both the lily and transgenic plants of Arabidopsis. Heterologous expression enhanced cell viability of the latter under high temperatures, high salt, and oxidative stress, and heat shock granules (HSGs formed under heat or salinity treatment. Assays of enzymes showed that LimHSP16.45 overexpression was related to greater activity by superoxide dismutase and catalase in transgenic lines. Therefore, we conclude that heterologous expression can protect plants against abiotic stresses by preventing irreversible protein aggregation, and by scavenging cellular reactive oxygen species.

  2. The ATAF1 transcription factor: At the convergence point of ABA-dependent plant defense against biotic and abiotic stresses

    Institute of Scientific and Technical Information of China (English)

    Brigitte Mauch-Mani; Victor Flors

    2009-01-01

    @@ Because of their sessile lifestyle, plants have evolved sophisticated ways of coping with the various biotic and abiotic stresses they can encounter during their life. Their defensive reac-tions to a given stress have to be rapid and well adapted to the situation. They are the results of tightly coordinated changes at the molecular level involving the contributions of different signaling pathways.

  3. Ecological relevance of strigolactones in nutrient uptake and other abiotic stresses, and in plant-microbe interactions below ground

    NARCIS (Netherlands)

    Andreo Jimenez, B.; Ruyter-Spira, C.P.; Bouwmeester, H.J.; Lopez-Raez, J.A.

    2015-01-01

    Background Plants are exposed to ever changing and often unfavourable environmental conditions, which cause both abiotic and biotic stresses. They have evolved sophisticated mechanisms to flexibly adapt themselves to these stress conditions. To achieve such adaptation, they need to control and coord

  4. Arabidopsis Raf-Like Mitogen-Activated Protein Kinase Kinase Kinase Gene Raf43 Is Required for Tolerance to Multiple Abiotic Stresses.

    Directory of Open Access Journals (Sweden)

    Nasar Virk

    Full Text Available Mitogen-activated protein kinase (MAPK cascades are critical signaling modules that mediate the transduction of extracellular stimuli into intracellular response. A relatively large number of MAPKKKs have been identified in a variety of plant genomes but only a few of them have been studied for their biological function. In the present study, we identified an Arabidopsis Raf-like MAPKKK gene Raf43 and studied its function in biotic and abiotic stress response using a T-DNA insertion mutant raf43-1 and two Raf43-overexpressing lines Raf43-OE#1 and Raf43-OE#13. Expression of Raf43 was induced by multiple abiotic and biotic stresses including treatments with drought, mannitol and oxidative stress or defense signaling molecule salicylic acid and infection with necrotrophic fungal pathogen Botrytis cinerea. Seed germination and seedling root growth of raf43-1 were significantly inhibited on MS medium containing mannitol, NaCl, H2O2 or methyl viologen (MV while seed germination and seedling root growth of the Raf43-OE#1 and Raf43-OE#13 lines was similar to wild type Col-0 under the above stress conditions. Soil-grown raf43-1 plants exhibited reduced tolerance to MV, drought and salt stress. Abscisic acid inhibited significantly seed germination and seedling root growth of the raf43-1 line but had no effect on the two Raf43-overexpressing lines. Expression of stress-responsive RD17 and DREB2A genes was significantly down-regulated in raf43-1 plants. However, the raf43-1 and Raf43-overexpressing plants showed similar disease phenotype to the wild type plants after infection with B. cinerea or Pseudomonas syringae pv. tomato DC3000. Our results demonstrate that Raf43, encoding for a Raf-like MAPKKK, is required for tolerance to multiple abiotic stresses in Arabidopsis.

  5. Genome-Wide Analysis of Genes Encoding Methionine-Rich Proteins in Arabidopsis and Soybean Suggesting Their Roles in the Adaptation of Plants to Abiotic Stress.

    Science.gov (United States)

    Chu, Ha Duc; Le, Quynh Ngoc; Nguyen, Huy Quang; Le, Dung Tien

    2016-01-01

    Oxidation and reduction of methionine (Met) play important roles in scavenging reactive oxygen species (ROS) and signaling in living organisms. To understand the impacts of Met oxidation and reduction in plants during stress, we surveyed the genomes of Arabidopsis and soybean (Glycine max L.) for genes encoding Met-rich proteins (MRPs). We found 121 and 213 genes encoding MRPs in Arabidopsis and soybean, respectively. Gene annotation indicated that those with known function are involved in vital cellular processes such as transcriptional control, calcium signaling, protein modification, and metal transport. Next, we analyzed the transcript levels of MRP-coding genes under normal and stress conditions. We found that 57 AtMRPs were responsive either to drought or to high salinity stress in Arabidopsis; 35 GmMRPs were responsive to drought in the leaf of late vegetative or early reproductive stages of soybean. Among the MRP genes with a known function, the majority of the abiotic stress-responsive genes are involved in transcription control and calcium signaling. Finally, Arabidopsis plant which overexpressed an MRP-coding gene, whose transcripts were downregulated by abiotic stress, was more sensitive to paraquat than the control. Taken together, our report indicates that MRPs participate in various vital processes of plants under normal and stress conditions. PMID:27635394

  6. Genome-Wide Analysis of Genes Encoding Methionine-Rich Proteins in Arabidopsis and Soybean Suggesting Their Roles in the Adaptation of Plants to Abiotic Stress

    Science.gov (United States)

    Chu, Ha Duc; Le, Quynh Ngoc; Nguyen, Huy Quang

    2016-01-01

    Oxidation and reduction of methionine (Met) play important roles in scavenging reactive oxygen species (ROS) and signaling in living organisms. To understand the impacts of Met oxidation and reduction in plants during stress, we surveyed the genomes of Arabidopsis and soybean (Glycine max L.) for genes encoding Met-rich proteins (MRPs). We found 121 and 213 genes encoding MRPs in Arabidopsis and soybean, respectively. Gene annotation indicated that those with known function are involved in vital cellular processes such as transcriptional control, calcium signaling, protein modification, and metal transport. Next, we analyzed the transcript levels of MRP-coding genes under normal and stress conditions. We found that 57 AtMRPs were responsive either to drought or to high salinity stress in Arabidopsis; 35 GmMRPs were responsive to drought in the leaf of late vegetative or early reproductive stages of soybean. Among the MRP genes with a known function, the majority of the abiotic stress-responsive genes are involved in transcription control and calcium signaling. Finally, Arabidopsis plant which overexpressed an MRP-coding gene, whose transcripts were downregulated by abiotic stress, was more sensitive to paraquat than the control. Taken together, our report indicates that MRPs participate in various vital processes of plants under normal and stress conditions.

  7. Evaluation of Arbuscular Mycorrhizal Fungi Capacity to Alleviate Abiotic Stress of Olive (Olea europaea L.) Plants at Different Transplant Conditions

    Science.gov (United States)

    Bompadre, María Josefina; Pérgola, Mariana; Fernández Bidondo, Laura; Colombo, Roxana Paula; Silvani, Vanesa Analía; Pardo, Alejandro Guillermo; Ocampo, Juan Antonio; Godeas, Alicia Margarita

    2014-01-01

    The capacity of roots to sense soil physicochemical parameters plays an essential role in maintaining plant nutritional and developmental functions under abiotic stress. These conditions generate reactive oxygen species (ROS) in plant tissues causing oxidation of proteins and lipids among others. Some plants have developed adaptive mechanisms to counteract such adverse conditions such as symbiotic association with arbuscular mycorrhizal fungi (AMF). AMF enhance plant growth and improve transplant survival by protecting host plants against environmental stresses. The aim of this study was to evaluate the alleviation of transplanting stress by two strains of Rhizophagus irregularis (GC2 and GA5) in olive. Our results show that olive plants have an additional energetic expense in growth due to an adaptative response to the growing stage and to the mycorrhizal colonization at the first transplant. However, at the second transplant the coinoculation improves olive plant growth and protects against oxidative stress followed by the GA5-inoculation. In conclusion, a combination of two AMF strains at the beginning of olive propagation produces vigorous plants successfully protected in field cultivation even with an additional cost at the beginning of growth. PMID:24688382

  8. Evaluation of arbuscular mycorrhizal fungi capacity to alleviate abiotic stress of olive (Olea europaea L.) plants at different transplant conditions.

    Science.gov (United States)

    Bompadre, María Josefina; Pérgola, Mariana; Fernández Bidondo, Laura; Colombo, Roxana Paula; Silvani, Vanesa Analía; Pardo, Alejandro Guillermo; Ocampo, Juan Antonio; Godeas, Alicia Margarita

    2014-01-01

    The capacity of roots to sense soil physicochemical parameters plays an essential role in maintaining plant nutritional and developmental functions under abiotic stress. These conditions generate reactive oxygen species (ROS) in plant tissues causing oxidation of proteins and lipids among others. Some plants have developed adaptive mechanisms to counteract such adverse conditions such as symbiotic association with arbuscular mycorrhizal fungi (AMF). AMF enhance plant growth and improve transplant survival by protecting host plants against environmental stresses. The aim of this study was to evaluate the alleviation of transplanting stress by two strains of Rhizophagus irregularis (GC2 and GA5) in olive. Our results show that olive plants have an additional energetic expense in growth due to an adaptative response to the growing stage and to the mycorrhizal colonization at the first transplant. However, at the second transplant the coinoculation improves olive plant growth and protects against oxidative stress followed by the GA5-inoculation. In conclusion, a combination of two AMF strains at the beginning of olive propagation produces vigorous plants successfully protected in field cultivation even with an additional cost at the beginning of growth.

  9. Evaluation of Arbuscular Mycorrhizal Fungi Capacity to Alleviate Abiotic Stress of Olive (Olea europaea L. Plants at Different Transplant Conditions

    Directory of Open Access Journals (Sweden)

    María Josefina Bompadre

    2014-01-01

    Full Text Available The capacity of roots to sense soil physicochemical parameters plays an essential role in maintaining plant nutritional and developmental functions under abiotic stress. These conditions generate reactive oxygen species (ROS in plant tissues causing oxidation of proteins and lipids among others. Some plants have developed adaptive mechanisms to counteract such adverse conditions such as symbiotic association with arbuscular mycorrhizal fungi (AMF. AMF enhance plant growth and improve transplant survival by protecting host plants against environmental stresses. The aim of this study was to evaluate the alleviation of transplanting stress by two strains of Rhizophagus irregularis (GC2 and GA5 in olive. Our results show that olive plants have an additional energetic expense in growth due to an adaptative response to the growing stage and to the mycorrhizal colonization at the first transplant. However, at the second transplant the coinoculation improves olive plant growth and protects against oxidative stress followed by the GA5-inoculation. In conclusion, a combination of two AMF strains at the beginning of olive propagation produces vigorous plants successfully protected in field cultivation even with an additional cost at the beginning of growth.

  10. The Response of a Putative Maize Zinc-Finger Protein Gene ZmAN14 in Transgenic Tabacco to Abiotic Stress%玉米锌指蛋白基因ZmAN14过表达转基因烟草对非生物胁迫的响应

    Institute of Scientific and Technical Information of China (English)

    宣宁; 柳絮; 张华; 陈高; 刘国霞; 边斐; 姚方印

    2015-01-01

    [Objective]ZmAN14is a member of the maize A20/AN1 zinc finger protein gene family. This gene family of rice is involved in the response to abiotic stress. The expression ofZmAN14inthe maize inbred line H21 and transgenic ZmAN14tobacco under abiotic stress was analyzed. The results will provide novel information for the comprehensive analysis of the functional and molecular mechanisms of maizeZmAN14and the entire gene family.[Method] Sequence analysis ofZmAN14was performed to confirm that this gene is a member of the maize A20/AN1 zinc finger protein gene family. The experiment was conducted by using maize inbred line H2. At the three-leaf stage, the seedlings were treated with multiple abiotic stress or induced by ABA. After treatment for 0, 1, 3, 6, 12 and 24 h, the whole plants were harvested. In the meantime, the roots, stems, leaves, coleptiles, pistil, stamen, silks and bract leaves were harvested from different growing periods of maize. Real-time quantitative fluorescence PCR was used to analyze the expression profile in different tissues and abiotic stress response ofZmAN14and its ABA-induced expression profile. Thecis-acting element of the promoter area was cloned to perform the comparative analysis. TheZmAN14coding sequence was cloned onto the GFP expressing vector pMDC85. A subcellular localization method was used to verify the localization of the ZmAN14 protein in the cell. TheZmAN14coding sequence was cloned onto the GAL4 DNA-binding domain vector. This vector was used to transform yeast. The transformed yeast was spotted onto the defect medium, and the resulted transcriptional activation activity was analyzed. TheZmAN14coding region was ligated to the plant expression vector p1300-221 to create an overexpression vector. The overexpression vector was transformed into tobacco. T2homozygous transgenic lines with highZmAN14 mRNA expression level were used to conduct salt-, drought- and ABA induced experiments, and its response to abiotic stress was

  11. Global analysis of WRKY transcription factor superfamily in Setaria identifies potential candidates involved in abiotic stress signalling

    Directory of Open Access Journals (Sweden)

    Mehanathan eMuthamilarasan

    2015-10-01

    Full Text Available Transcription factors (TFs are major players in stress signalling and constitute an integral part of signalling networks. Among the major TFs, WRKY proteins play pivotal roles in regulation of transcriptional reprogramming associated with stress responses. In view of this, genome- and transcriptome-wide identification of WRKY TF family was performed in the C4 model plants, Setaria italica (SiWRKY and S. viridis (SvWRKY, respectively. The study identified 105 SiWRKY and 44 SvWRKY proteins that were computationally analysed for their physicochemical properties. Sequence alignment and phylogenetic analysis classified these proteins into three major groups, namely I, II and III with majority of WRKY proteins belonging to group II (53 SiWRKY and 23 SvWRKY, followed by group III (39 SiWRKY and 11 SvWRKY and group I (10 SiWRKY and 6 SvWRKY. Group II proteins were further classified into 5 subgroups (IIa to IIe based on their phylogeny. Domain analysis showed the presence of WRKY motif and zinc finger-like structures in these proteins along with additional domains in a few proteins. All SiWRKY genes were physically mapped on the S. italica genome and their duplication analysis revealed that 10 and 8 gene pairs underwent tandem and segmental duplications, respectively. Comparative mapping of SiWRKY and SvWRKY genes in related C4 panicoid genomes demonstrated the orthologous relationships between these genomes. In silico expression analysis of SiWRKY and SvWRKY genes showed their differential expression patterns in different tissues and stress conditions. Expression profiling of candidate SiWRKY genes in response to stress (dehydration and salinity and hormone treatments (abscisic acid, salicylic acid and methyl jasmonate suggested the putative involvement of SiWRKY066 and SiWRKY082 in stress and hormone signalling. These genes could be potential candidates for further characterization to delineate their functional roles in abiotic stress signalling.

  12. Ethylene-inhibiting compound 1-MCP delays leaf senescence in cotton plants under abiotic stress conditions

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuan; J T Cothren; CHEN De-hua; Amir M H Ibrahim; Leonardo Lombardini

    2015-01-01

    Cotton (Gossypium hirsutum L.) plants produce more ethylene when subjected to abiotic stresses, such as high temperatures and drought, which result in premature leaf senescence, reduced photosynthetic efifciency, and thus decreased yield. This study was conducted to test the hypothesis that the ethylene-inhibiting compound 1-methylcyclopropene (1-MCP) treatment of cotton plants can delay leaf senescence under high temperature, drought, and the aging process in control ed environ-mental conditions. Potted cotton plants were exposed to 1-MCP treatment at the early square stage of development. The protective effect of 1-MCP against membrane damage was found on older compared to younger leaves, indicating 1-MCP could lower the stress level caused by aging. Application of 1-MCP resulted in reduction of lipid peroxidation, membrane leakage, soluble sugar content, and increased chlorophyl content, in contrast to the untreated plants under heat stress, suggesting that 1-MCP treatment of cotton plants may also have the potential to reduce the effect of heat stress in terms of delayed senescence. Application of 1-MCP caused reductions of lipid peroxidation, membrane leakage, and soluble sugar content, together with increases in water use efifciency (WUE), water potential, chlorophyl content, and lfuorescence quantum efifciency, compared to the untreated plants under drought, suggesting that 1-MCP treatment of cotton plants may also have the ability to reduce the level of stress under drought conditions. In conclusion, 1-MCP treatment of cotton should have the potential to delay senescence under heat and drought stress, and the aging process. Additional y, 1-MCP is more effective under stress than under non-stress conditions.

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

    OpenAIRE

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

    2013-01-01

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

  14. Four potato (Solanum tuberosum) ABCG transporters and their expression in response to abiotic factors and Phytophthora infestans infection.

    Science.gov (United States)

    Ruocco, Michelina; Ambrosino, Patrizia; Lanzuise, Stefania; Woo, Sheridan Lois; Lorito, Matteo; Scala, Felice

    2011-12-15

    Pleiotropic drug resistant (PDR/ABCG) genes are involved in plant response to biotic and abiotic stresses. In this work, we cloned, from Solanum tuberosum, four PDR/ABCG transporter genes named StPDR1, StPDR2, StPDR3 and StPDR4, which were differentially expressed in plant tissues and cell cultures. A number of different chemically unrelated compounds were found to regulate the transcript levels of the four genes in cultured cells. In particular, StPDR2 was highly up-regulated in the presence of Botrytis cinerea cell walls, NaCl, 2,4-dichlorophenol, sclareol and α-solanin and biological compounds. The expression of the genes was also investigated by real time RT-PCR during infection by Phytophthora infestans. StPDR1 and StPDR2 were up-regulated about 13- and 37-fold at 48 h post-infection (hpi), StPDR3 was expressed (4-5-fold) at 24 and 48 hpi and then rapidly decreased, while StPDR4 RNA accumulation was stimulated (about 4-fold) at 12 and 24 hpi, decreased at 48 hpi and increased again at 96 hpi. We discuss the role of StPDR1-4 genes in response to pathogens and abiotic stresses.

  15. Building the crops of tomorrow: advantages of symbiont-based approaches to improving abiotic stress tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Tringe, Susannah; Coleman-Derr, Devin

    2014-05-22

    The exponential growth in world population is feeding a steadily increasing global need for arable farmland, a resource that is already in high demand. This trend has led to increased farming on subprime arid and semi-arid lands, where limited availability of water and a host of environmental stresses often severely reduce crop productivity. The conventional approach to mitigating the abiotic stresses associated with arid climes is to breed for stress-tolerant cultivars, a time and labor intensive venture that often neglects the complex ecological context of the soil environment in which the crop is grown. In recent years, studies have attempted to identify microbial symbionts capable of conferring the same stress-tolerance to their plant hosts, and new developments in genomic technologies have greatly facilitated such research. Here, we highlight many of the advantages of these symbiont-based approaches and argue in favor of the broader recognition of crop species as ecological niches for a diverse community of microorganisms that function in concert with their plant hosts and each other to thrive under fluctuating environmental conditions

  16. Building the crops of tomorrow: advantages of symbiont-based approaches to improving abiotic stress tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Coleman-Derr, Devin [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Tringe, Susannah G. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States)

    2014-06-06

    The exponential growth in world population is feeding a steadily increasing global need for arable farmland, a resource that is already in high demand. This trend has led to increased farming on subprime arid and semi-arid lands, where limited availability of water and a host of environmental stresses often severely reduce crop productivity. The conventional approach to mitigating the abiotic stresses associated with arid climes is to breed for stress-tolerant cultivars, a time and labor intensive venture that often neglects the complex ecological context of the soil environment in which the crop is grown. In recent years, studies have attempted to identify microbial symbionts capable of conferring the same stress-tolerance to their plant hosts, and new developments in genomic technologies have greatly facilitated such research. Here in this paper, we highlight many of the advantages of these symbiont-based approaches and argue in favor of the broader recognition of crop species as ecological niches for a diverse community of microorganisms that function in concert with their plant hosts and each other to thrive under fluctuating environmental conditions

  17. Building the crops of tomorrow: advantages of symbiont-based approaches to improving abiotic stress tolerance

    Directory of Open Access Journals (Sweden)

    Devin eColeman-Derr

    2014-06-01

    Full Text Available The exponential growth in world population is feeding a steadily increasing global need for arable farmland, a resource that is already in high demand. This trend has led to increased farming on subprime arid and semi-arid lands, where limited availability of water and a host of environmental stresses often severely reduce crop productivity. The conventional approach to mitigating the abiotic stresses associated with arid climes is to breed for stress-tolerant cultivars, a time and labor intensive venture that often neglects the complex ecological context of the soil environment in which the crop is grown. In recent years, studies have attempted to identify microbial symbionts capable of conferring the same stress-tolerance to their plant hosts, and new developments in genomic technologies have greatly facilitated such research. Here, we highlight many of the advantages of these symbiont-based approaches and argue in favor of the broader recognition of crop species as ecological niches for a diverse community of microorganisms that function in concert with their plant hosts and each other to thrive under fluctuating environmental conditions.

  18. Abiotic stress modifies the synthesis of alpha-tocopherol and beta-carotene in phytoplankton species.

    Science.gov (United States)

    Häubner, Norbert; Sylvander, Peter; Vuori, Kristiina; Snoeijs, Pauline

    2014-08-01

    We performed laboratory experiments to investi-gate whether the synthesis of the antioxidants α-tocopherol (vitamin E) and β-carotene in phytoplankton depends on changes in abiotic factors. Cultures of Nodularia spumigena, Phaeodactylum tricornutum, Skeletonema costatum, Dunaliella tertiolecta, Prorocentrum cordatum, and Rhodomonas salina were incubated at different tempe-ratures, photon flux densities and salinities for 48 h. We found that abiotic stress, within natural ecological ranges, affects the synthesis of the two antioxidants in different ways in different species. In most cases antioxidant production was stimulated by increased abiotic stress. In P. tricornutum KAC 37 and D. tertiolecta SCCAP K-0591, both good producers of this compound, α-tocopherol accumulation was negatively affected by environmentally induced higher photosystem II efficiency (Fv /Fm ). On the other hand, β-carotene accumulation was positively affected by higher Fv /Fm in N. spumigena KAC 7, P. tricornutum KAC 37, D. tertiolecta SCCAP K-0591 and R. salina SCCAP K-0294. These different patterns in the synthesis of the two compounds may be explained by their different locations and functions in the cell. While α-tocopherol is heavily involved in the protection of prevention of lipid peroxidation in membranes, β-carotene performs immediate photo-oxidative protection in the antennae complex of photosystem II. Overall, our results suggest a high variability in the antioxidant pool of natural aquatic ecosystems, which can be subject to short-term temperature, photon flux density and salinity fluctuations. The antioxidant levels in natural phytoplankton communities depend on species composition, the physiological condition of the species, and their respective strategies to deal with reactive oxygen species. Since α-tocopherol and β-carotene, as well as many other nonenzymatic antioxidants, are exclusively produced by photo-synthetic organisms, and are required by higher

  19. A wheat lipid transfer protein (TdLTP4) promotes tolerance to abiotic and biotic stress in Arabidopsis thaliana.

    Science.gov (United States)

    Safi, Hela; Saibi, Walid; Alaoui, Meryem Mrani; Hmyene, Abdelaziz; Masmoudi, Khaled; Hanin, Moez; Brini, Faïçal

    2015-04-01

    Lipid transfer proteins (LTPs) are members of the family of pathogenesis-related proteins (PR-14) that are believed to be involved in plant defense responses. In this study, we report the isolation and characterization of a novel gene TdLTP4 encoding an LTP protein from durum wheat [Triticum turgidum L. subsp. Durum Desf.]. Molecular Phylogeny analyses of wheat TdLTP4 gene showed a high identity to other plant LTPs. Predicted three-dimensional structural model revealed the presence of six helices and nine loop turns. Expression analysis in two local durum wheat varieties with marked differences in salt and drought tolerance, revealed a higher transcript accumulation of TdLTP4 under different stress conditions in the tolerant variety, compared to the sensitive one. The overexpression of TdLTP4 in Arabidopsis resulted in a promoted plant growth under various stress conditions including NaCl, ABA, JA and H2O2 treatments. Moreover, the LTP-overexpressing lines exhibit less sensitivity to jasmonate than wild-type plants. Furthermore, detached leaves from transgenic Arabidopsis expressing TdLTP4 gene showed enhanced fungal resistance against Alternaria solani and Botrytis cinerea. Together, these data provide the evidence for the involvement of TdLTP4 gene in the tolerance to both abiotic and biotic stresses in crop plants. PMID:25703105

  20. Expression analysis of a novel pyridoxal kinase messenger RNA splice variant, PKL, in oil rape suffering abiotic stress and phytohormones

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Pyridoxal kinase is key enzyme for the biosynthesis of pyridoxal 5'-phosphate, the biologically active form of vitamin B6, in the salvage pathway. A pyridoxal kinase gene, BnPKL (GenBank accession No. DQ463962), was isolated from oilseed rape (Brassica napus L.) following water stress through rapid amplification of complementary DNA (cDNA) ends. The results showed that the gene had two splice variants: PKL and PKL2. PKL, the long cDNA, encodes a 334 amino acid protein with a complete ATP-binding site, pyridoxai kinase-binding site and dimer interface site of a pyridoxal kinase, while PKL2, the short cDNA, lacked a partial domain. Southern blot showed that there were two copies in Brassica napus. The expression of BnPKL cDNA could rescue the mutant phenotype of Escherichia coil defective in pyridoxai kinase. Real-time reverse transcription-polymerase chain reaction revealed that the relative abundance of two transcripts are modulated by development and environmental stresses.Abscisic acid and NaCI were inclined to decrease PKL expression, but HO and cold temperatures induced the PKL expression. In addition, the PKL expression could be transiently induced by jasmonate acid at an early stage, abscisic acid, salicylic acid and jasmonate acid enhanced the PKL expression in roots. Our results demonstrated that BnPKL was a pyridoxal kinase involved in responses to biotic and abiotic stresses.

  1. Overexpression of VOZ2 confers biotic stress tolerance but decreases abiotic stress resistance in Arabidopsis

    OpenAIRE

    Nakai, Yusuke; Fujiwara, Sumire; Kubo, Yasuyuki; Sato, Masa H.

    2013-01-01

    VOZ (vascular plant one zinc-finger protein) is a plant specific one-zinc finger type transcriptional activator, which is highly conserved through land plant evolution. We have previously shown that loss-of-function mutations in VOZ1 and VOZ2 showed increased cold and drought stress tolerances whereas decreased biotic stress resistance in Arabidopsis. Here, we demonstrate that transgenic plants overexpressing VOZ2 impairs freezing and drought stress tolerances but increases resistance to a fu...

  2. Abiotic Stress Tolerance of Charophyte Green Algae: New Challenges for Omics Techniques.

    Science.gov (United States)

    Holzinger, Andreas; Pichrtová, Martina

    2016-01-01

    Charophyte green algae are a paraphyletic group of freshwater and terrestrial green algae, comprising the classes of Chlorokybophyceae, Coleochaetophyceae, Klebsormidiophyceae, Zygnematophyceae, Mesostigmatophyceae, and Charo- phyceae. Zygnematophyceae (Conjugating green algae) are considered to be closest algal relatives to land plants (Embryophyta). Therefore, they are ideal model organisms for studying stress tolerance mechanisms connected with transition to land, one of the most important events in plant evolution and the Earth's history. In Zygnematophyceae, but also in Coleochaetophyceae, Chlorokybophyceae, and Klebsormidiophyceae terrestrial members are found which are frequently exposed to naturally occurring abiotic stress scenarios like desiccation, freezing and high photosynthetic active (PAR) as well as ultraviolet (UV) irradiation. Here, we summarize current knowledge about various stress tolerance mechanisms including insight provided by pioneer transcriptomic and proteomic studies. While formation of dormant spores is a typical strategy of freshwater classes, true terrestrial groups are stress tolerant in vegetative state. Aggregation of cells, flexible cell walls, mucilage production and accumulation of osmotically active compounds are the most common desiccation tolerance strategies. In addition, high photophysiological plasticity and accumulation of UV-screening compounds are important protective mechanisms in conditions with high irradiation. Now a shift from classical chemical analysis to next-generation genome sequencing, gene reconstruction and annotation, genome-scale molecular analysis using omics technologies followed by computer-assisted analysis will give new insights in a systems biology approach. For example, changes in transcriptome and role of phytohormone signaling in Klebsormidium during desiccation were recently described. Application of these modern approaches will deeply enhance our understanding of stress reactions in an

  3. THE PROTECTIVE EFFECT OF BRASSINOSTEROIDS ON MILLET PLANTS UNDER ABIOTIC STRESSES

    Directory of Open Access Journals (Sweden)

    Vayner A. O.

    2014-10-01

    Full Text Available The effect of brassinosteroids on the resistance of millet plants (Panicum miliaceum L. to damaging heating and soil drought was investigated. The pretreatment of the seeds with 20 nM of 24-epibrassinolide and 28-homobrassinolide solutions increased the survival rate of seedlings after their exposure to hyperthermia (heating in bath of water ultrathermostat at 47 °C for 10 min. Under the influence of brassinosteroids the increase in activity of antioxidant enzymes (superoxide dismutase, catalase, and guaiacol peroxidase and the decrease in the content of lipid peroxidation product malondialdehyde in millet seedlings after heat stress were observed. In this case, the protective effect of 24-epibrassinolide was more significant as compared to the effect of 28-homobrassinolide. In the conditions of drought (the decrease of soil moisture to 25% of field water capacity plants grown from seeds treated by 24-epibrassinolide exhibited ability for growth and higher activity of the antioxidant enzymes compared to control plants. A conclusion concerning the essential role of the induction of antioxidant enzymes in implementation of the protective effect of brassinosteroids on millet plants under abiotic stresses and the prospects of practical application of presowing treatment with them for prolonged non-specific activation of plant resistance was made.

  4. Overexpression of stress-inducible OsBURP16, the β subunit of polygalacturonase 1, decreases pectin content and cell adhesion and increases abiotic stress sensitivity in rice.

    Science.gov (United States)

    Liu, Huanhuan; Ma, Yan; Chen, Na; Guo, Siyi; Liu, Huili; Guo, Xiaoyu; Chong, Kang; Xu, Yunyuan

    2014-05-01

    Polygalacturonase (PG), one of the hydrolases responsible for cell wall pectin degradation, is involved in organ consenescence and biotic stress in plants. PG1 is composed of a catalytic subunit, PG2, and a non-catalytic PG1β subunit. OsBURP16 belongs to the PG1β-like subfamily of BURP-family genes and encodes one putative PG1β subunit precursor in rice (Oryza sativa L.). Transcription of OsBURP16 is induced by cold, salinity and drought stresses, as well as by abscisic acid (ABA) treatment. Analysis of plant survival rates, relative ion leakage rates, accumulation levels of H2 O2 and water loss rates of leaves showed that overexpression of OsBURP16 enhanced sensitivity to cold, salinity and drought stresses compared with controls. Young leaves of Ubi::OsBURP16 transgenic plants showed reduced cell adhesion and increased cuticular transpiration rate. Mechanical strength measurement of Ubi::OsBURP16 plants showed that reduced force was required to break leaves as compared with wild type. Transgenic rice showed enhanced PG activity and reduced pectin content. All these results suggested that overexpression of OsBURP16 caused pectin degradation and affected cell wall integrity as well as transpiration rate, which decreased tolerance to abiotic stresses. PMID:24237159

  5. The Role of Plant bZIP Transcription Factors in Abiotic Stress%植物bZIP转录因子在非生物胁迫中的作用

    Institute of Scientific and Technical Information of China (English)

    冉静; 邹杰; 刘爱玲; 陈信波

    2012-01-01

    The abiotic stress factors, drought, salt and extreme temperature, have seriously impact on plant growth. The basic leucine zipper (bZIP) transcription factors, which were identified in various plants, have been proved to be involved in responding process to various abiotic stresses. The role of plant bZIP transcription factors in the response to abiotic stress and its latest advances were reviewed.%非生物胁迫因子如干旱、高温、低温和盐碱等严重影响着植物的生长发育,碱性亮氨酸拉链( bZIP)类转录因子与非生物逆境胁迫响应有密切关联.综述了植物bZIP类转录因子在应答非生物逆境胁迫中的作用及研究进展.

  6. De novo transcriptome sequence assembly and identification of AP2/ERF transcription factor related to abiotic stress in parsley (Petroselinum crispum.

    Directory of Open Access Journals (Sweden)

    Meng-Yao Li

    Full Text Available Parsley is an important biennial Apiaceae species that is widely cultivated as herb, spice, and vegetable. Previous studies on parsley principally focused on its physiological and biochemical properties, including phenolic compound and volatile oil contents. However, little is known about the molecular and genetic properties of parsley. In this study, 23,686,707 high-quality reads were obtained and assembled into 81,852 transcripts and 50,161 unigenes for the first time. Functional annotation showed that 30,516 unigenes had sequence similarity to known genes. In addition, 3,244 putative simple sequence repeats were detected in curly parsley. Finally, 1,569 of the identified unigenes belonged to 58 transcription factor families. Various abiotic stresses have a strong detrimental effect on the yield and quality of parsley. AP2/ERF transcription factors have important functions in plant development, hormonal regulation, and abiotic response. A total of 88 putative AP2/ERF factors were identified from the transcriptome sequence of parsley. Seven AP2/ERF transcription factors were selected in this study to analyze the expression profiles of parsley under different abiotic stresses. Our data provide a potentially valuable resource that can be used for intensive parsley research.

  7. Systematic analysis of glycogen synthase kinase 3 genes in rice reveals their differential responses to phytohormones and abiotic stresses%水稻GSK基因家族的鉴定及其对多种激素和逆境应答的表达量分析

    Institute of Scientific and Technical Information of China (English)

    宋亚玲; 熊立仲

    2012-01-01

    The glycogen synthase kinase 3 (GSK3)/SHAGGY-like kinases are serine/threonine protein kina-ses involved in a variety of biological processes. In this study,nine GSK3-like genes (OsGSKl-9) were identified in rice,and they are distributed on six chromosomes, and the distribution pattern is related to the chromosomal block duplication events in rice. The OsGSK proteins can be classified into four subgroups. The expression patterns of OsGSK genes were investigated in various tissues and organs of rice and in the seedlings treated with phytohormones and abiotic stresses. The results suggest that most of OsGSK genes have high expression level in the whole life cycle,and they are responsive not only to different phytohormones (such as abscisic acid,auxin,and brassinosteroid) but also to drought and salt stresses,implying that OsGSK genes may have important roles in development and stress responses in rice.%通过序列比对分析鉴定出9个GSK同源基因(命名为OsGSK1 -9),它们分布在水稻的6条染色体上.聚类分析表明预测的OsGSK蛋白和其他植物中的GSK蛋白可被分为4个亚组.通过实时定量PCR进一步分析了OsGSK基因家族的基因在水稻各种组织和器官以及在多种逆境胁迫和植物激素处理条件下的表达量.结果表明:大多数OsGSK基因在水稻全生育期都有较高的表达量并且受多种激素(如脱落酸、生长素、油菜素内酯)和逆境(如干旱和盐胁迫)胁迫诱导表达,表明OsGSK基因家族在水稻发育和逆境适应过程中可能起重要作用.

  8. Monsoonal variability in abiotic parameters in coastal waters off Trivandrum evokes press and pulse response in biotic variables

    Digital Repository Service at National Institute of Oceanography (India)

    Subina, N.S.; Bhosle, S.; Nair, S.; Lokabharathi, P.A.

    Trivandrum Coast experiences coastal upwelling during south west monsoon, which is accompanied by abiotic changes in physio-chemical parameters. The resultant biotic responses could range from an instantaneous pulse to a sustained press reaction...

  9. AP2/ERF转录因子对植物非生物胁迫应答的研究进展%Advances of Researches on AP2/ERF Transcription Factor Response to Plant Abiotic Stress

    Institute of Scientific and Technical Information of China (English)

    崔喜艳; 陈众峰; 陈展宇

    2015-01-01

    植物AP2/ERF(APETALA 2/ethylene-responsive element binding factor)是一个庞大的转录因子超家族,其蛋白质中均含有1或2段60~70个氨基酸残基组成的AP2/ERF结构域,存在于所有植物中.AP2/ERF转录因子参与多种生物学过程,包括干旱、高盐、低温等逆境胁迫响应等.在植物受到逆境刺激后,脱落酸、乙烯等信号相应地被激活,并激活AP2/ERF转录因子的表达,从而调控功能基因的表达.文中对国内外近年来有关植物AP2/ERF类转录因子的分类、结构特点、分布、信号传导途径及基因调节等方面的研究进行了综述.

  10. Towards the Identification of New Genes Involved in ABA-Dependent Abiotic Stresses Using Arabidopsis Suppressor Mutants of abh1 Hypersensitivity to ABA during Seed Germination

    Directory of Open Access Journals (Sweden)

    Iwona Szarejko

    2013-06-01

    Full Text Available Abscisic acid plays a pivotal role in the abiotic stress response in plants. Although great progress has been achieved explaining the complexity of the stress and ABA signaling cascade, there are still many questions to answer. Mutants are a valuable tool in the identification of new genes or new alleles of already known genes and in elucidating their role in signaling pathways. We applied a suppressor mutation approach in order to find new components of ABA and abiotic stress signaling in Arabidopsis. Using the abh1 (ABA hypersensitive 1 insertional mutant as a parental line for EMS mutagenesis, we selected several mutants with suppressed hypersensitivity to ABA during seed germination. Here, we present the response to ABA and a wide range of abiotic stresses during the seed germination and young seedling development of two suppressor mutants—soa2 (suppressor of abh1 hypersensitivity to ABA 2 and soa3 (suppressor of abh1 hypersensitivity to ABA 3. Generally, both mutants displayed a suppression of the hypersensitivity of abh1 to ABA, NaCl and mannitol during germination. Both mutants showed a higher level of tolerance than Columbia-0 (Col-0—the parental line of abh1 in high concentrations of glucose. Additionally, soa2 exhibited better root growth than Col-0 in the presence of high ABA concentrations. soa2 and soa3 were drought tolerant and both had about 50% fewer stomata per mm2 than the wild-type but the same number as their parental line—abh1. Taking into account that suppressor mutants had the same genetic background as their parental line—abh1, it was necessary to backcross abh1 with Landsberg erecta four times for the map-based cloning approach. Mapping populations, derived from the cross of abh1 in the Landsberg erecta background with each suppressor mutant, were created. Map based cloning in order to identify the suppressor genes is in progress.

  11. Ectopic Expression of an Atypical Hydrophobic Group 5 LEA Protein from Wild Peanut, Arachis diogoi Confers Abiotic Stress Tolerance in Tobacco.

    Directory of Open Access Journals (Sweden)

    Akanksha Sharma

    Full Text Available Late embryogenesis abundant (LEA proteins are a group of hydrophilic proteins, which accumulate in plants under varied stress conditions like drought, salinity, extreme temperatures and oxidative stress suggesting their role in the protection of plants against these stresses. A transcript derived fragment (TDF corresponding to LEA gene, which got differentially expressed in wild peanut, Arachis diogoi against the late leaf spot pathogen, Phaeoisariopsis personata was used in this study. We have cloned its full length cDNA by RACE-PCR, which was designated as AdLEA. AdLEA belongs to the atypical Group 5C of LEA protein family as confirmed by sequence analysis. Group 5C LEA protein subfamily contains Pfam LEA_2 domain and is highly hydrophobic. In native conditions, expression of AdLEA was upregulated considerably upon hormonal and abiotic stress treatments emphasizing its role in abiotic stress tolerance. Subcellular localization studies showed that AdLEA protein is distributed in both nucleus and cytosol. Ectopic expression of AdLEA in tobacco resulted in enhanced tolerance of plants to dehydration, salinity and oxidative stress with the transgenic plants showing higher chlorophyll content and reduced lipid peroxidation as compared to wild type plants. Overexpressed AdLEA tobacco plants maintained better photosynthetic efficiency under drought conditions as demonstrated by chlorophyll fluorescence measurements. These plants showed enhanced transcript accumulation of some stress-responsive genes. Our study also elucidates that ROS levels were significantly reduced in leaves and stomatal guard cells of transgenic plants upon stress treatments. These results suggest that AdLEA confers multiple stress tolerance to plants, which make it a potential gene for genetic modification in plants.

  12. Ectopic Expression of an Atypical Hydrophobic Group 5 LEA Protein from Wild Peanut, Arachis diogoi Confers Abiotic Stress Tolerance in Tobacco.

    Science.gov (United States)

    Sharma, Akanksha; Kumar, Dilip; Kumar, Sumit; Rampuria, Sakshi; Reddy, Attipalli R; Kirti, Pulugurtha Bharadwaja

    2016-01-01

    Late embryogenesis abundant (LEA) proteins are a group of hydrophilic proteins, which accumulate in plants under varied stress conditions like drought, salinity, extreme temperatures and oxidative stress suggesting their role in the protection of plants against these stresses. A transcript derived fragment (TDF) corresponding to LEA gene, which got differentially expressed in wild peanut, Arachis diogoi against the late leaf spot pathogen, Phaeoisariopsis personata was used in this study. We have cloned its full length cDNA by RACE-PCR, which was designated as AdLEA. AdLEA belongs to the atypical Group 5C of LEA protein family as confirmed by sequence analysis. Group 5C LEA protein subfamily contains Pfam LEA_2 domain and is highly hydrophobic. In native conditions, expression of AdLEA was upregulated considerably upon hormonal and abiotic stress treatments emphasizing its role in abiotic stress tolerance. Subcellular localization studies showed that AdLEA protein is distributed in both nucleus and cytosol. Ectopic expression of AdLEA in tobacco resulted in enhanced tolerance of plants to dehydration, salinity and oxidative stress with the transgenic plants showing higher chlorophyll content and reduced lipid peroxidation as compared to wild type plants. Overexpressed AdLEA tobacco plants maintained better photosynthetic efficiency under drought conditions as demonstrated by chlorophyll fluorescence measurements. These plants showed enhanced transcript accumulation of some stress-responsive genes. Our study also elucidates that ROS levels were significantly reduced in leaves and stomatal guard cells of transgenic plants upon stress treatments. These results suggest that AdLEA confers multiple stress tolerance to plants, which make it a potential gene for genetic modification in plants. PMID:26938884

  13. Effect of Abiotic Stresses on Histidine kinases Gene Expression in Zea mays L. cv. SC. 704

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    Javadmanesh, Susan

    2013-02-01

    Full Text Available UV-B radiation and osmotic stress (like drought and salinity have a significant effect on physiology, morphology, biochemistry and molecular biology. To cope with such stimuli, plants must be able to effectively sense, respond to and adapt to changes in their biological activities. Hence, signal transduction pathways play important role in response to environmental stimuli. In this study, the expression of three Histidine Kinases including ZmHK1, ZmHK2 and ZmHK3a was studied in maize plants exposed to 8 days drought, salinity and UV-B stresses applying transcript approach. The semi-quantitative RT-PCR analyses of ZmHKs showed up-regulation of ZmHK1 and ZmHK3 agenes after 8 days exposure to applied stresses except salinity in leaves, although, their regulation was more prominent during drought stress. Astonishingly, exposure to these stresses showed down-regulation of all genes in maize roots. However, the ZmHK1 behavior was quite different from two other homologues and showed up-regulation in combined stresses. We suggest that ZmHK1 and ZmHK3a, as cytokinin transmembrane receptors, sense osmolarity changes in cells caused by dehydration. Our data supports the involvement of ZmHK homologues under these stresses in maize and provides a gene expression dynamics during the stress which will be valuable for further studies of the molecular mechanisms of stress tolerance in maize.

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

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    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

  15. Abiotic stress leads to somatic and heritable changes in homologous recombination frequency, point mutation frequency and microsatellite stability in Arabidopsis plants

    International Nuclear Information System (INIS)

    In earlier studies, we showed that abiotic stresses, such as ionizing radiation, heavy metals, temperature and water, trigger an increase in homologous recombination frequency (HRF). We also demonstrated that many of these stresses led to inheritance of high-frequency homologous recombination, HRF. Although an increase in recombination frequency is an important indicator of genome rearrangements, it only represents a minor portion of possible stress-induced mutations. Here, we analyzed the influence of heat, cold, drought, flood and UVC abiotic stresses on two major types of mutations in the genome, point mutations and small deletions/insertions. We used two transgenic lines of Arabidopsis thaliana, one allowing an analysis of reversions in a stop codon-containing inactivated β-glucuronidase transgene and another one allowing an analysis of repeat stability in a microsatellite-interrupted β-glucuronidase transgene. The transgenic Arabidopsis line carrying the β-glucuronidase-based homologous recombination substrate was used as a positive control. We showed that the majority of stresses increased the frequency of point mutations, homologous recombination and microsatellite instability in somatic cells, with the frequency of homologous recombination being affected the most. The analysis of transgenerational changes showed an increase in HRF to be the most prominent effect observed in progeny. Significant changes in recombination frequency were observed upon exposure to all types of stress except drought, whereas changes in microsatellite instability were observed upon exposure to UVC, heat and cold. The frequency of point mutations in the progeny of stress-exposed plants was the least affected; an increase in mutation frequency was observed only in the progeny of plants exposed to UVC. We thus conclude that transgenerational changes in genome stability in response to stress primarily involve an increase in recombination frequency.

  16. Abiotic stress leads to somatic and heritable changes in homologous recombination frequency, point mutation frequency and microsatellite stability in Arabidopsis plants

    Energy Technology Data Exchange (ETDEWEB)

    Yao Youli, E-mail: youli.yao@uleth.ca [Department of Biological Sciences, University of Lethbridge, Lethbridge, T1K 3M4 Alberta (Canada); Kovalchuk, Igor, E-mail: igor.kovalchuk@uleth.ca [Department of Biological Sciences, University of Lethbridge, Lethbridge, T1K 3M4 Alberta (Canada)

    2011-02-10

    In earlier studies, we showed that abiotic stresses, such as ionizing radiation, heavy metals, temperature and water, trigger an increase in homologous recombination frequency (HRF). We also demonstrated that many of these stresses led to inheritance of high-frequency homologous recombination, HRF. Although an increase in recombination frequency is an important indicator of genome rearrangements, it only represents a minor portion of possible stress-induced mutations. Here, we analyzed the influence of heat, cold, drought, flood and UVC abiotic stresses on two major types of mutations in the genome, point mutations and small deletions/insertions. We used two transgenic lines of Arabidopsis thaliana, one allowing an analysis of reversions in a stop codon-containing inactivated {beta}-glucuronidase transgene and another one allowing an analysis of repeat stability in a microsatellite-interrupted {beta}-glucuronidase transgene. The transgenic Arabidopsis line carrying the {beta}-glucuronidase-based homologous recombination substrate was used as a positive control. We showed that the majority of stresses increased the frequency of point mutations, homologous recombination and microsatellite instability in somatic cells, with the frequency of homologous recombination being affected the most. The analysis of transgenerational changes showed an increase in HRF to be the most prominent effect observed in progeny. Significant changes in recombination frequency were observed upon exposure to all types of stress except drought, whereas changes in microsatellite instability were observed upon exposure to UVC, heat and cold. The frequency of point mutations in the progeny of stress-exposed plants was the least affected; an increase in mutation frequency was observed only in the progeny of plants exposed to UVC. We thus conclude that transgenerational changes in genome stability in response to stress primarily involve an increase in recombination frequency.

  17. Foxtail Millet NF-Y Families: Genome-Wide Survey and Evolution Analyses Identified Two Functional Genes Important in Abiotic Stresses.

    Science.gov (United States)

    Feng, Zhi-Juan; He, Guan-Hua; Zheng, Wei-Jun; Lu, Pan-Pan; Chen, Ming; Gong, Ya-Ming; Ma, You-Zhi; Xu, Zhao-Shi

    2015-01-01

    It was reported that Nuclear Factor Y (NF-Y) genes were involved in abiotic stress in plants. Foxtail millet (Setaria italica), an elite stress tolerant crop, provided an impetus for the investigation of the NF-Y families in abiotic responses. In the present study, a total of 39 NF-Y genes were identified in foxtail millet. Synteny analyses suggested that foxtail millet NF-Y genes had experienced rapid expansion and strong purifying selection during the process of plant evolution. De novo transcriptome assembly of foxtail millet revealed 11 drought up-regulated NF-Y genes. SiNF-YA1 and SiNF-YB8 were highly activated in leaves and/or roots by drought and salt stresses. Abscisic acid (ABA) and H2O2 played positive roles in the induction of SiNF-YA1 and SiNF-YB8 under stress treatments. Transient luciferase (LUC) expression assays revealed that SiNF-YA1 and SiNF-YB8 could activate the LUC gene driven by the tobacco (Nicotiana tobacam) NtERD10, NtLEA5, NtCAT, NtSOD, or NtPOD promoter under normal or stress conditions. Overexpression of SiNF-YA1 enhanced drought and salt tolerance by activating stress-related genes NtERD10 and NtCAT1 and by maintaining relatively stable relative water content (RWC) and contents of chlorophyll, superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and malondialdehyde (MDA) in transgenic lines under stresses. SiNF-YB8 regulated expression of NtSOD, NtPOD, NtLEA5, and NtERD10 and conferred relatively high RWC and chlorophyll contents and low MDA content, resulting in drought and osmotic tolerance in transgenic lines under stresses. Therefore, SiNF-YA1 and SiNF-YB8 could activate stress-related genes and improve physiological traits, resulting in tolerance to abiotic stresses in plants. All these results will facilitate functional characterization of foxtail millet NF-Ys in future studies. PMID:26734043

  18. Foxtail millet NF-Y families: genome-wide survey and evolution analyses identified two functional genes important in abiotic stresses

    Directory of Open Access Journals (Sweden)

    Zhi-Juan eFeng

    2015-12-01

    Full Text Available It was reported that Nuclear Factor Y (NF-Y genes were involved in abiotic stress in plants. Foxtail millet (Setaria italica, an elite stress tolerant crop, provided an impetus for the investigation of the NF-Y families in abiotic responses. In the present study, a total of 39 NF-Y genes were identified in foxtail millet. Synteny analyses suggested that foxtail millet NF-Y genes had experienced rapid expansion and strong purifying selection during the process of plant evolution. De novo transcriptome assembly of foxtail millet revealed 11 drought up-regulated NF-Y genes. SiNF-YA1 and SiNF-YB8 were highly activated in leaves and/or roots by drought and salt stresses. Abscisic acid (ABA and H2O2 played positive roles in the induction of SiNF-YA1 and SiNF-YB8 under stress treatments. Transient luciferase (LUC expression assays revealed that SiNF-YA1 and SiNF-YB8 could activate the LUC gene driven by the tobacco (Nicotiana tobacam NtERD10, NtLEA5, NtCAT, NtSOD or NtPOD promoter under normal or stress conditions. Overexpression of SiNF-YA1 enhanced drought and salt tolerance by activating stress-related genes NtERD10 and NtCAT1 and by maintaining relatively stable relative water content (RWC and contents of chlorophyll, superoxide dismutase (SOD, peroxidase (POD, catalase (CAT and malondialdehyde (MDA in transgenic lines under stresses. SiNF-YB8 regulated expression of NtSOD, NtPOD, NtLEA5 and NtERD10 and conferred relatively high RWC and chlorophyll contents and low MDA content, resulting in drought and osmotic tolerance in transgenic lines under stresses. Therefore, SiNF-YA1 and SiNF-YB8 could activate stress-related genes and improve physiological traits, resulting in tolerance to abiotic stresses in plants. All these results will facilitate functional characterization of foxtail millet NF-Ys in future studies.

  19. Using the Model Perennial Grass Brachypodium sylvaticum to Engineer Resistance to Multiple Abiotic Stresses

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, Sean; Reguera, Maria; Sade, Nir; Cartwright, Amy; Tobias, Christian; Thilmony, Roger; Blumwald, Eduardo; Vogel, John

    2015-03-20

    We are using the perennial model grass Brachypodium sylvaticum to identify combinations of transgenes that enhance tolerance to multiple, simultaneous abiotic stresses. The most successful transgene combinations will ultimately be used to create improved switchgrass (Panicum virgatum L.) cultivars. To further develop B. sylvaticum as a perennial model grass, and facilitate our planned transcriptional profiling, we are sequencing and annotating the genome. We have generated ~40x genome coverage using PacBio sequencing of the largest possible size selected libraries (18, 22, 25 kb). Our initial assembly using only long-read sequence contained 320 Mb of sequence with an N50 contig length of 315 kb and an N95 contig length of 40 kb. This assembly consists of 2,430 contigs, the largest of which was 1.6 Mb. The estimated genome size based on c-values is 340 Mb indicating that about 20 Mb of presumably repetitive DNA remains yet unassembled. Significantly, this assembly is far superior to an assembly created from paired-end short-read sequence, ~100x genome coverage. The short-read-only assembly contained only 226 Mb of sequence in 19k contigs. To aid the assembly of the scaffolds into chromosome-scale assemblies we produced an F2 mapping population and have genotyped 480 individuals using a genotype by sequence approach. One of the reasons for using B. sylvaticum as a model system is to determine if the transgenes adversely affect perenniality and winter hardiness. Toward this goal, we examined the freezing tolerance of wild type B. sylvaticum lines to determine the optimal conditions for testing the freezing tolerance of the transgenics. A survey of seven accessions noted significant natural variation in freezing tolerance. Seedling or adult Ain-1 plants, the line used for transformation, survived an 8 hour challenge down to -6 oC and 50% survived a challenge down to -9 oC. Thus, we will be able to easily determine if the transgenes compromise freezing tolerance. In the

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

    OpenAIRE

    Showler, Allan T.

    2016-01-01

    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 i...

  1. Cloning of a Plasma Membrane Protein Gene TaPM19-1 and Its Response to Abiotic Stresses in Wheat%小麦质膜蛋白基因TaPM19-1的克隆及其对非生物胁迫的响应

    Institute of Scientific and Technical Information of China (English)

    李永春; 张春艳; 张宁; 孟凡荣; 任江萍; 牛洪斌; 王翔; 尹钧

    2012-01-01

    [目的]分析小麦质膜蛋白基因TaPM19-1的特征及其对非生物胁迫的响应,并探讨其在小麦抗逆调控过程中的生物学功能.[方法]利用RACE技术克隆了该基因cDNA全长,采用生物信息学方法分析克隆基因编码蛋白的特性,并通过半定量RT-PCR分析该基因在非生物胁迫条件下的表达特性.[结果]TaPM19-1的cDNA全长1090 bp,无内含子,编码蛋白包含182个氨基酸,分子量为19.02 kD,包含有典型的AWPM19保守域;依据氨基酸序列将来源于不同植物的16个AWPM19类蛋白分为3组,TaPM19-1与2个来源于大麦及1个二穗短柄草的AWPM19类蛋白亲源关系最近,同属于第三组.高级结构分析显示,TaPM19-1可形成4个由α-螺旋组成的跨膜域,N端位于膜内,包含由27个氨基酸组成的信号肽,C端近40个氨基酸位于膜内.表达分析显示,TaPM19-1除在发育后期的种子中有较高水平表达外,其它组织中未检测到表达;在所检测的2个小麦品种根系中,TaPM19-1的表达受ABA诱导,但在叶片中的表达量极低;水分胁迫条件下,该基因在根系和叶片中均呈现较强的诱导表达特性;在高盐和高温胁迫条件下,该基因在洛旱2号小麦中均可诱导表达,而在中国春小麦中未检测到该基因表达;在低温胁迫条件下,未检测到TaPM19-1的表达.[结论]获得了小麦质膜蛋白基因TaPM19-1的cDNA 全长,其编码蛋白可形成典型的跨膜结构特征;该基因受植物激素ABA的诱导,在洛旱2号中也可被干旱、高盐和高温胁迫诱导,但在中国春中对高盐和高温胁迫无响应.推测TaPM19-1在洛旱2号和中国春中存在不同的转录调控机制.%[Objective] The characteristics of a plasma membrane protein gene TaPM19-1 and its response to abiotic stresses in wheat were studied, which will provide an insight into its biological roles involved in the molecular mechanisms of abiotic-sterss response in wheat. [Method] RACE technology was

  2. Barley Genes as Tools to Confer Abiotic Stress Tolerance in Crops.

    Science.gov (United States)

    Gürel, Filiz; Öztürk, Zahide N; Uçarlı, Cüneyt; Rosellini, Daniele

    2016-01-01

    Barley is one of the oldest cultivated crops in the world with a high adaptive capacity. The natural tolerance of barley to stress has led to increasing interest in identification of stress responsive genes through small/large-scale omics studies, comparative genomics, and overexpression of some of these genes by genetic transformation. Two major categories of proteins involved in stress tolerance are transcription factors (TFs) responsible from the re-programming of the metabolism in stress environment, and genes encoding Late Embryogenesis Abundant (LEA) proteins, antioxidant enzymes, osmolytes, and transporters. Constitutive overexpression of several barley TFs, such as C-repeat binding factors (HvCBF4), dehydration-responsive element-binding factors (HvDREB1), and WRKYs (HvWRKY38), in transgenic plants resulted in higher tolerance to drought and salinity, possibly by effectively altering the expression levels of stress tolerance genes due to their higher DNA binding affinity. Na(+)/H(+) antiporters, channel proteins, and lipid transporters can also be the strong candidates for engineering plants for tolerance to salinity and low temperatures. PMID:27536305

  3. High yielding semidwarf Pokkali rice mutants tolerant to abiotic stresses of coastal saline ecosystem

    International Nuclear Information System (INIS)

    The most popular rice varieties in the pokkali tract of Kerala State, India are Pokkali, Cheruvirippu, VTL-3 and VTL- 4. These varieties are tall, lodging genotypes having tolerance to complex abiotic stresses (salinity, acidity and submergence). About 50% yield is lost due to lodging. In the present study, an effort was made to induce semi dwarfism coupled with high yield in these genotypes retaining the complex tolerance. Dry seeds of these varieties were subjected to both physical mutagen (gamma rays 200, 300, 400 and 500Gy) and chemical mutagen treatment (0.5%, 1% and 2% of Ethyl Methane Sulphonate at varying exposure periods of 8h, 16h and 24h). Reduced germination percentage was noticed in all the treatments. Only 25% plants of VTL-3 irradiated with 400 Gy dose of gamma rays produced fertile seeds and 28% in VTL-4. Even in the fertile plants the seed fertility varied greatly (0.5 to 82.4%). The induction of 100% sterility in more than 75% plants of 400 Gy irradiated treatments compared to the maximum of 7% sterility in the untreated control indicated the high mutagenic potency of gamma irradiation in pokkali rice. Fifty eight semi dwarf mutants with significant reduction in plant height could be selected from the M2 generation of 400 Gy irradiated doze of VTL-3. The height of the selected plants varied from 82 cm to 120cm chemical mutagen treatment was not effective in inducing semidwarfism. More than 70% of the selected mutants showed stability for reduced plant height. The segregation data suggested that most of the mutant lines had single recessive mutations with the exception of few lines. The yield of the stable mutants were evaluated in an Initial Evaluation Trial and observed that some of the mutants had the potential to produce about double the yield (10 tons/ha) of its parent VTL-3 (5 tons/ha). (author)

  4. Dominant Repression by Arabidopsis Transcription Factor MYB44 Causes Oxidative Damage and Hypersensitivity to Abiotic Stress

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    Helene Persak

    2014-02-01

    Full Text Available In any living species, stress adaptation is closely linked with major changes of the gene expression profile. As a substrate protein of the rapidly stress-induced mitogen-activated protein kinase MPK3, Arabidopsis transcription factor MYB44 likely acts at the front line of stress-induced re-programming. We recently characterized MYB44 as phosphorylation-dependent positive regulator of salt stress signaling. Molecular events downstream of MYB44 are largely unknown. Although MYB44 binds to the MBSII element in vitro, it has no discernible effect on MBSII-driven reporter gene expression in plant co-transfection assays. This may suggest limited abundance of a synergistic co-regulator. MYB44 carries a putative transcriptional repression (Ethylene responsive element binding factor-associated Amphiphilic Repression, EAR motif. We employed a dominant repressor strategy to gain insights into MYB44-conferred stress resistance. Overexpression of a MYB44-REP fusion markedly compromised salt and drought stress tolerance—the opposite was seen in MYB44 overexpression lines. MYB44-mediated resistance likely results from induction of tolerance-enhancing, rather than from repression of tolerance-diminishing factors. Salt stress-induced accumulation of destructive reactive oxygen species is efficiently prevented in transgenic MYB44, but accelerated in MYB44-REP lines. Furthermore, heterologous overexpression of MYB44-REP caused tissue collapse in Nicotiana. A mechanistic model of MAPK-MYB-mediated enhancement in the antioxidative capacity and stress tolerance is proposed. Genetic engineering of MYB44 variants with higher trans-activating capacity may be a means to further raise stress resistance in crops.

  5. Metabolite profiling reveals abiotic stress tolerance in Tn5 mutant of Pseudomonas putida.

    Directory of Open Access Journals (Sweden)

    Vasvi Chaudhry

    Full Text Available Pseudomonas is an efficient plant growth-promoting rhizobacteria (PGPR; however, intolerance to drought and high temperature limit its application in agriculture as a bioinoculant. Transposon 5 (Tn5 mutagenesis was used to generate a stress tolerant mutant from a PGPR Pseudomonas putida NBRI1108 isolated from chickpea rhizosphere. A mutant NBRI1108T, selected after screening of nearly 10,000 transconjugants, exhibited significant tolerance towards high temperature and drought. Southern hybridization analysis of EcoRI and XhoI restricted genomic DNA of NBRI1108T confirmed that it had a single Tn5 insertion. The metabolic changes in the polar and non-polar extracts of NBRI1108 and NBRI1108T were examined using 1H, 31P nuclear magnetic resonance (NMR spectroscopy and gas chromatography-mass spectrometry (GC-MS. Thirty six chemically diverse metabolites consisting of amino acids, fatty acids and phospholipids were identified and quantified. Insertion of Tn5 influenced amino acid and phospholipid metabolism and resulted in significantly higher concentration of aspartic acid, glutamic acid, glycinebetaine, glycerophosphatidylcholine (GPC and putrescine in NBRI1108T as compared to that in NBRI1108. The concentration of glutamic acid, glycinebetaine and GPC increased by 34%, 95% and 100%, respectively in the NBRI1108T as compared to that in NBRI1108. High concentration of glycerophosphatidylethanolamine (GPE and undetected GPC in NBRI1108 indicates that biosynthesis of GPE may have taken place via the methylation pathway of phospholipid biosynthesis. However, high GPC and low GPE concentration in NBRI1108T suggest that methylation pathway and phosphatidylcholine synthase (PCS pathway of phospholipid biosynthesis are being followed in the NBRI1108T. Application of multivariate principal component analysis (PCA on the quantified metabolites revealed clear variations in NBRI1108 and NBRI1108T in polar and non-polar metabolites. Identification of abiotic

  6. Pigeonpea hybrid-proline-rich protein (CcHyPRP confers biotic and abiotic stress tolerance in transgenic rice

    Directory of Open Access Journals (Sweden)

    Venkateswara Rao eKhareedu

    2016-01-01

    Full Text Available In this study, we report the overexpression of Cajanus cajan hybrid-proline-rich protein encoding gene (CcHyPRP in rice which resulted in increased tolerance to both abiotic and biotic stresses. Compared to the control plants, the transgenic rice lines, expressing CcHyPRP, exhibited high-level tolerance against major abiotic stresses, viz., drought, salinity and heat, as evidenced by increased biomass, chlorophyll content, survival rate, root and shoot growth. Further, transgenic rice lines showed increased panicle size and grain number compared to the control plants under different stress conditions. The CcHyPRP transgenics, as compared to the control, revealed enhanced activities of catalase and superoxide dismutase (SOD enzymes and reduced malondialdehyde (MDA levels. Expression pattern of CcHyPRP::GFP fusion-protein confirmed its predominant localization in cell walls. Moreover, the CcHyPRP transgenics, as compared to the control, exhibited increased resistance to the fungal pathogen Magnaporthe grisea which causes blast disease in rice. Higher levels of bZIP and endochitinase transcripts as well as endochitinase activity were observed in transgenic rice compared to the control plants. The overall results demonstrate the intrinsic role of CcHyPRP in conferring multiple stress tolerance at the whole-plant level. The multipotent CcHyPRP seems promising as a prime candidate gene to fortify crop plants for enhanced tolerance/resistance to different stress factors.

  7. 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.

  8. Pigeonpea Hybrid-Proline-Rich Protein (CcHyPRP) Confers Biotic and Abiotic Stress Tolerance in Transgenic Rice.

    Science.gov (United States)

    Mellacheruvu, Sunitha; Tamirisa, Srinath; Vudem, Dashavantha Reddy; Khareedu, Venkateswara Rao

    2015-01-01

    In this study, we report the overexpression of Cajanus cajan hybrid-proline-rich protein encoding gene (CcHyPRP) in rice which resulted in increased tolerance to both abiotic and biotic stresses. Compared to the control plants, the transgenic rice lines, expressing CcHyPRP, exhibited high-level tolerance against major abiotic stresses, viz., drought, salinity, and heat, as evidenced by increased biomass, chlorophyll content, survival rate, root, and shoot growth. Further, transgenic rice lines showed increased panicle size and grain number compared to the control plants under different stress conditions. The CcHyPRP transgenics, as compared to the control, revealed enhanced activities of catalase and superoxide dismutase (SOD) enzymes and reduced malondialdehyde (MDA) levels. Expression pattern of CcHyPRP::GFP fusion-protein confirmed its predominant localization in cell walls. Moreover, the CcHyPRP transgenics, as compared to the control, exhibited increased resistance to the fungal pathogen Magnaporthe grisea which causes blast disease in rice. Higher levels of bZIP and endochitinase transcripts as well as endochitinase activity were observed in transgenic rice compared to the control plants. The overall results demonstrate the intrinsic role of CcHyPRP in conferring multiple stress tolerance at the whole-plant level. The multipotent CcHyPRP seems promising as a prime candidate gene to fortify crop plants for enhanced tolerance/resistance to different stress factors. PMID:26834756

  9. Abiotic stresses affect differently the intron splicing and expression of chloroplast genes in coffee plants (Coffea arabica) and rice (Oryza sativa).

    Science.gov (United States)

    Nguyen Dinh, Sy; Sai, Than Zaw Tun; Nawaz, Ghazala; Lee, Kwanuk; Kang, Hunseung

    2016-08-20

    Despite the increasing understanding of the regulation of chloroplast gene expression in plants, the importance of intron splicing and processing of chloroplast RNA transcripts under stress conditions is largely unknown. Here, to understand how abiotic stresses affect the intron splicing and expression patterns of chloroplast genes in dicots and monocots, we carried out a comprehensive analysis of the intron splicing and expression patterns of chloroplast genes in the coffee plant (Coffea arabica) as a dicot and rice (Oryza sativa) as a monocot under abiotic stresses, including drought, cold, or combined drought and heat stresses. The photosynthetic activity of both coffee plants and rice seedlings was significantly reduced under all stress conditions tested. Analysis of the transcript levels of chloroplast genes revealed that the splicing of tRNAs and mRNAs in coffee plants and rice seedlings were significantly affected by abiotic stresses. Notably, abiotic stresses affected differently the splicing of chloroplast tRNAs and mRNAs in coffee plants and rice seedlings. The transcript levels of most chloroplast genes were markedly downregulated in both coffee plants and rice seedlings upon stress treatment. Taken together, these results suggest that coffee and rice plants respond to abiotic stresses via regulating the intron splicing and expression of different sets of chloroplast genes. PMID:27448724

  10. The surgically induced stress response.

    Science.gov (United States)

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

    2013-09-01

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

  11. Chromatin changes in response to drought, salinity, heat, and cold stresses in plants

    Directory of Open Access Journals (Sweden)

    Jong-Myong eKim

    2015-03-01

    Full Text Available Chromatin regulation is essential to regulate genes and genome activities. In plants, the alteration of histone modification and DNA methylation are coordinated with changes in the expression of stress-responsive genes to adapt to environmental changes. Several chromatin regulators have been shown to be involved in the regulation of stress-responsive gene networks under abiotic stress conditions. Specific histone modification sites and the histone modifiers that regulate key stress-responsive genes have been identified by genetic and biochemical approaches, revealing the importance of chromatin regulation in plant stress responses. Recent studies have also suggested that histone modification plays an important role in plant stress memory. In this review, we summarize recent progress on the regulation and alteration of histone modification (acetylation, methylation, phosphorylation, and SUMOylation in response to the abiotic stresses, drought, high-salinity, heat, and cold in plants.

  12. Delayed germination of Arabidopsis seeds under chilling stress by overexpressing an abiotic stress inducible GhTPS11.

    Science.gov (United States)

    Wang, Cai-Li; Zhang, Shi-Cai; Qi, Sheng-Dong; Zheng, Cheng-Chao; Wu, Chang-Ai

    2016-01-10

    Trehalose-6-phosphate synthase (TPS) plays an important role in metabolic regulation and stress responses in a variety of organisms. However information about cotton TPS is poor. Here a cotton TPS gene GhTPS11 was isolated and characterized. Expression analysis revealed that GhTPS11 was induced in 20-day old cotton seedlings by heat drought and high salt stresses as well as GA and ABA. Moreover GhTPS11 was induced by chilling stress and mannitol while was depressed by sucrose. Tissue expression analysis indicated that GhTPS11 expressed higher in leaves than in stems and roots of 20-day old cotton seedlings. The GhTPS11 overexpressing Arabidopsis seeds germinated slower than the wild-type (WT) under chilling stress. Trehalose-6-phosphate (T6P) and trehalose contents were evidently higher in GhTPS11 overexpressing lines 3, 5, and 22 than in WT under normal germination condition as well as chilling stress. Further analysis demonstrated that the expression of ICE1 CBF3 and RCI2A was induced lower whereas that of CBF1 and CBF2 was induced higher under chilling stress in the GhTPS11 overexpressing seeds than WT respectively. These results suggested that GhTPS11 encoded a stress-responsive TPS protein and functioned in chilling stress during seed germination. Perhaps the chilling stress sensitivity of transgenic Arabidopsis seeds was caused by the expression changes of at least some chilling-related genes such as ICE1 CBFs and RCI2A other than HOS1. So this article provided the useful information for GhTPS11 usage for crop molecular breeding.

  13. Genome-wide analysis of the maize (Zea may L.) CPP-like gene family and expression profiling under abiotic stress.

    Science.gov (United States)

    Song, X Y; Zhang, Y Y; Wu, F C; Zhang, L

    2016-01-01

    Cysteine-rich polycomb-like (CPP) proteins are members of a small family of transcription factors, which have been identified and characterized in Arabidopsis, rice, and soybean. In this study, we investigated CPP-like genes in the maize genome. The results revealed 13 putative CPP-like genes, which were found to encode 17 distinct transcripts and were distributed unequally on 7 of 10 maize chromosomes. Analysis of phylogenetic relationships showed that Arabidopsis, rice, and maize CPP-like transcription factors can be grouped into two subfamilies. We also used real-time RT-PCR to evaluate changes in the transcript levels of ZmCPP genes in response to abiotic stresses (heat, cold, salt, and drought stresses). These findings provide an overview of the evolution of the ZmCPP gene family, which will aid in the functional characterization of CPP-like genes in maize growth and development. PMID:27525875

  14. Plant abiotic stress diagnostic by laser induced chlorophyll fluorescence spectral analysis of in vivo leaf tissue of biofuel species

    Science.gov (United States)

    Gouveia-Neto, Artur S.; Silva, Elias A., Jr.; Costa, Ernande B.; Bueno, Luciano A.; Silva, Luciana M. H.; Granja, Manuela M. C.; Medeiros, Maria J. L.; Câmara, Terezinha J. R.; Willadino, Lilia G.

    2010-02-01

    Laser induced fluorescence is exploited to evaluate the effect of abiotic stresses upon the evolution and characteristics of in vivo chlorophyll emission spectra of leaves tissues of brazilian biofuel plants species(Saccharum officinarum and Jatropha curcas). The chlorophyll fluorescence spectra of 20 min predarkened intact leaves were studied employing several excitation wavelengths in the UV-VIS spectral region. Red(Fr) and far-red (FFr) chlorophyll fluorescence emission signals around 685 nm and 735 nm, respectively, were analyzed as a function of the stress intensity and the time of illumination(Kautsky effect). The Chl fluorescence ratio Fr/FFr which is a valuable nondestructive indicator of the chlorophyll content of leaves was investigated during a period of time of 30 days. The dependence of the Chl fluorescence ratio Fr/FFr upon the intensity of the abiotic stress(salinity) was examined. The results indicated that the salinity plays a major hole in the chlorophyll concentration of leaves in both plants spieces, with a significant reduction in the chlorophyll content for NaCl concentrations in the 25 - 200 mM range. The laser induced chlorophyll fluorescence analysis allowed detection of damage caused by salinity in the early stages of the plants growing process, and can be used as an early-warning indicator of salinity stress

  15. Expression analysis of genes encoding mitogen-activated protein kinases in maize provides a key link between abiotic stress signaling and plant reproduction.

    Science.gov (United States)

    Sun, Wei; Chen, Hao; Wang, Juan; Sun, Hong Wei; Yang, Shu Ke; Sang, Ya Lin; Lu, Xing Bo; Xu, Xiao Hui

    2015-01-01

    Mitogen-activated protein kinases (MAPKs) play important roles in stress responses and development in plants. Maize (Zea mays), an important cereal crop, is a model plant species for molecular studies. In the last decade, several MAPKs have been identified in maize; however, their functions have not been studied extensively. Genome-wide identification and expression analysis of maize MAPK genes could provide valuable information for understanding their functions. In this study, 20 non-redundant maize MAPK genes (ZmMPKs) were identified via a genome-wide survey. Phylogenetic analysis of MAPKs from maize, rice (Oryza sativa), Arabidopsis (Arabidopsis thaliana), poplar (Populus trichocarpa), and tomato (Solanum lycopersicum) classified them into four major classes. ZmMPKs in the same class had similar domains, motifs, and genomic structures. Gene duplication investigations suggested that segmental duplications made a large contribution to the expansion of ZmMPKs. A number of cis-acting elements related to plant development and response to stress and hormones were identified in the promoter regions of ZmMPKs. Furthermore, transcript profile analysis in eight tissues and organs at various developmental stages demonstrated that most ZmMPKs were preferentially expressed in reproductive tissues and organs. The transcript abundance of most ZmMPKs changed significantly under salt, drought, cold, or abscisic acid (ABA) treatments, implying that they might participate in abiotic stress and ABA signaling. These expression analyses indicated that ZmMPKs might serve as linkers between abiotic stress signaling and plant reproduction. Our data will deepen our understanding of the complexity of the maize MAPK gene family and provide new clues to investigate their functions.

  16. A novel gene SbSI-2 encoding nuclear protein from a halophyte confers abiotic stress tolerance in E. coli and tobacco.

    Directory of Open Access Journals (Sweden)

    Narendra Singh Yadav

    Full Text Available Salicornia brachiata is an extreme halophyte that grows luxuriantly in coastal marshes. Previously, we have reported isolation and characterization of ESTs from Salicornia with large number of novel/unknown salt-responsive gene sequences. In this study, we have selected a novel salt-inducible gene SbSI-2 (Salicornia brachiata salt-inducible-2 for functional characterization. Bioinformatics analysis revealed that SbSI-2 protein has predicted nuclear localization signals and a strong protein-protein interaction domain. Transient expression of the RFP:SbSI2 fusion protein confirmed that SbSI-2 is a nuclear-localized protein. Genomic organization study showed that SbSI-2 is intronless and has a single copy in Salicornia genome. Quantitative RT-PCR analysis revealed higher SbSI-2 expression under salt stress and desiccation conditions. The SbSI-2 gene was transformed in E. coli and tobacco for functional characterization. pET28a-SbSI-2 recombinant E. coli cells showed higher tolerance to desiccation and salinity compared to vector alone. Transgenic tobacco plants overexpressing SbSI-2 have improved salt- and osmotic tolerance, accompanied by better growth parameters, higher relative water content, elevated accumulation of compatible osmolytes, lower Na+ and ROS accumulation and lesser electrolyte leakage than the wild-type. Overexpression of the SbSI-2 also enhanced transcript levels of ROS-scavenging genes and some stress-related transcription factors under salt and osmotic stresses. Taken together, these results demonstrate that SbSI-2 might play an important positive modulation role in abiotic stress tolerance. This identifies SbSI-2 as a novel determinant of salt/osmotic tolerance and suggests that it could be a potential bioresource for engineering abiotic stress tolerance in crop plants.

  17. A comparative study of fatty acid profile and formation of biofilm in Geobacillus gargensis exposed to variable abiotic stress.

    Science.gov (United States)

    Al-Beloshei, Noor Essa; Al-Awadhi, Husain; Al-Khalaf, Rania A; Afzal, Mohammad

    2015-01-01

    Understanding bacterial fatty acid (FA) profile has a great taxonomic significance as well as clinical importance for diagnosis issues. Both the composition and nature of membrane FAs change under different nutritional, biotic and (or) abiotic stresses, and environmental stress. Bacteria produce both odd-carbon as well as branched-chain fatty acids (BCFAs). This study was designed to examine the effect of abiotic pressure, including salinity, temperature, pH, and oxinic stress on the growth, development, and FA profile in thermophilic Geobacillus gargensis. Under these stresses, 3 parametric ratios, 2-methyl fatty acids/3-methyl fatty acids (iso-/anteiso-FAs), BCFAs/straight-chain saturated fatty acids (SCSFA), and SCSFAs/straight-chain unsaturated fatty acids (SCUFA), in addition to total lipids affected by variable stresses were measured. Our results indicate that the ratio of total iso-/anteiso-FAs increased at the acidic pH range of 4.1-5.2 and decreased with increasing pH. The reverse was true for salt stress when iso-/anteiso-FAs ratio increased with salt concentration. The BCFAs/SCSFAs and SCSFAs/SCUFAs ratios increased at neutral and alkaline pH and high salt concentration, reduced incubation time, and comparatively high temperature (55-65 °C) of the growth medium. The bacterial total lipid percentage deceased with increasing salt concentration, incubation period, but it increased with temperature. The formation of extracellular polymeric substances was observed under all stress conditions and with the addition of sodium dodecyl sulfate (2 and 5 mmol/L) to the growth medium. The membrane phospholipid composition of the bacterium was analyzed by thin-layer chromatography.

  18. A comparative study of fatty acid profile and formation of biofilm in Geobacillus gargensis exposed to variable abiotic stress.

    Science.gov (United States)

    Al-Beloshei, Noor Essa; Al-Awadhi, Husain; Al-Khalaf, Rania A; Afzal, Mohammad

    2015-01-01

    Understanding bacterial fatty acid (FA) profile has a great taxonomic significance as well as clinical importance for diagnosis issues. Both the composition and nature of membrane FAs change under different nutritional, biotic and (or) abiotic stresses, and environmental stress. Bacteria produce both odd-carbon as well as branched-chain fatty acids (BCFAs). This study was designed to examine the effect of abiotic pressure, including salinity, temperature, pH, and oxinic stress on the growth, development, and FA profile in thermophilic Geobacillus gargensis. Under these stresses, 3 parametric ratios, 2-methyl fatty acids/3-methyl fatty acids (iso-/anteiso-FAs), BCFAs/straight-chain saturated fatty acids (SCSFA), and SCSFAs/straight-chain unsaturated fatty acids (SCUFA), in addition to total lipids affected by variable stresses were measured. Our results indicate that the ratio of total iso-/anteiso-FAs increased at the acidic pH range of 4.1-5.2 and decreased with increasing pH. The reverse was true for salt stress when iso-/anteiso-FAs ratio increased with salt concentration. The BCFAs/SCSFAs and SCSFAs/SCUFAs ratios increased at neutral and alkaline pH and high salt concentration, reduced incubation time, and comparatively high temperature (55-65 °C) of the growth medium. The bacterial total lipid percentage deceased with increasing salt concentration, incubation period, but it increased with temperature. The formation of extracellular polymeric substances was observed under all stress conditions and with the addition of sodium dodecyl sulfate (2 and 5 mmol/L) to the growth medium. The membrane phospholipid composition of the bacterium was analyzed by thin-layer chromatography. PMID:25496258

  19. Brassica napus L. Homeodomain Leucine-Zipper Gene BnHB6 Responds to Abiotic and Biotic Stresses

    Institute of Scientific and Technical Information of China (English)

    Shun-Wu YU; Li-Da ZHANG; Kai-Jing ZUO; Dong-Qin TANG; Xiao-Fen SUN; Ke-Xuan TANG

    2005-01-01

    Ahomeodomain leucine-zipper(HD-Zip) gene BnHB6 (GenBank accession No. AY336103) was isolated from oilseed rape (Brassica napus L.) following drought treatment through rapid amplification of cDNA ends (RACE). The full-length cDNA of BnHB6 was 1 611 bp and contained a 936-bp open reading frame encoding 311 amino acids. Sequence analysis indicated that BnHB6 belonged to the HD-Zip I subfamily.High-stringency Southern boltting analysis showed that BnHB6 appeared in rape as a single copy but had homologous genes. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that BnHB6 was expressed in several tissues tested under control conditions, but that expression was significantly upregulated in shoots by mannitol, NaCl, cold treatment, anaerobic culture, wounding, H2O2, abscisic acid (ABA), and salicylic acid (SA) treatments, but not by ultraviolet treatment. Further RTPCR analysis revealed that BnHB6 was a late-responsive gene, the expression of which was not activated by NaCl, cold treatment, H2O2, ABA, and SA at an early time point (20 min) of treatment in the shoot. However, after a certain period of treatment, the induced expression culminated and then declined until the next peak occurred. Tissue-specific analysis revealed that BnHB6 was expressed at certain levels in the roots, shoots, and flowers, and the roots were found to respond to the osmotic stimuli more rapidly than shoots to increase the expression of BnHB6. The present study implies that BnHB6 plays a positive role as a regulator of biotic and abiotic stresses on growth during seedling establishment.

  20. Comprehensive genomic analysis and expression profiling of phospholipase C gene family during abiotic stresses and development in rice.

    Directory of Open Access Journals (Sweden)

    Amarjeet Singh

    Full Text Available BACKGROUND: Phospholipase C (PLC is one of the major lipid hydrolysing enzymes, implicated in lipid mediated signaling. PLCs have been found to play a significant role in abiotic stress triggered signaling and developmental processes in various plant species. Genome wide identification and expression analysis have been carried out for this gene family in Arabidopsis, yet not much has been accomplished in crop plant rice. METHODOLOGY/PRINCIPAL FINDINGS: An exhaustive in-silico exploration of rice genome using various online databases and tools resulted in the identification of nine PLC encoding genes. Based on sequence, motif and phylogenetic analysis rice PLC gene family could be divided into phosphatidylinositol-specific PLCs (PI-PLCs and phosphatidylcholine- PLCs (PC-PLC or NPC classes with four and five members, respectively. A comparative analysis revealed that PLCs are conserved in Arabidopsis (dicots and rice (monocot at gene structure and protein level but they might have evolved through a separate evolutionary path. Transcript profiling using gene chip microarray and quantitative RT-PCR showed that most of the PLC members expressed significantly and differentially under abiotic stresses (salt, cold and drought and during various developmental stages with condition/stage specific and overlapping expression. This finding suggested an important role of different rice PLC members in abiotic stress triggered signaling and plant development, which was also supported by the presence of relevant cis-regulatory elements in their promoters. Sub-cellular localization of few selected PLC members in Nicotiana benthamiana and onion epidermal cells has provided a clue about their site of action and functional behaviour. CONCLUSION/SIGNIFICANCE: The genome wide identification, structural and expression analysis and knowledge of sub-cellular localization of PLC gene family envisage the functional characterization of these genes in crop plants in near

  1. Learning from Evolution: Thellungiella Generates New Knowledge on Essential and Critical Components of Abiotic Stress Tolerance in Plants

    Institute of Scientific and Technical Information of China (English)

    Anna Amtmann

    2009-01-01

    Thellungiella salsuginea (halophila) is a close relative of Arabidopsis thaliana but, unlike A. thaliana, it grows well in extreme conditions of cold, salt, and drought as well as nitrogen limitation. Over the last decade, many laboratories have started to use Thellungiella to investigate the physiological, metabolic, and molecular mechanisms of abiotic stress tolerance in plants, and new knowledge has been gained in particular with respect to ion transport and gene expression.The advantage of Thellungiella over other extremophile model plants is that it can be directly compared with Arabidopsis,and therefore generate information on both essential and critical components of stress tolerance. Thellungiella research is supported by a growing body of technical resources comprising physiological and molecular protocols, ecotype collections,expressed sequence tags, cDNA-libraries, microarrays, and a pending genome sequence. This review summarizes the current state of knowledge on Thellungiella and re-evaluates its usefulness as a model for research into plant stress tolerance.

  2. AhpC (alkyl hydroperoxide reductase) from Anabaena sp. PCC 7120 protects Escherichia coli from multiple abiotic stresses

    International Nuclear Information System (INIS)

    Alkyl hydroperoxide reductase (AhpC) is known to detoxify peroxides and reactive sulfur species (RSS). However, the relationship between its expression and combating of abiotic stresses is still not clear. To investigate this relationship, the genes encoding the alkyl hydroperoxide reductase (ahpC) from Anabaena sp. PCC 7120 were introduced into E. coli using pGEX-5X-2 vector and their possible functions against heat, salt, carbofuron, cadmium, copper and UV-B were analyzed. The transformed E. coli cells registered significantly increase in growth than the control cells under temperature (47 oC), NaCl (6% w/v), carbofuron (0.025 mg ml-1), CdCl2 (4 mM), CuCl2 (1 mM), and UV-B (10 min) exposure. Enhanced expression of ahpC gene as measured by semi-quantitative RT-PCR under aforementioned stresses at different time points demonstrated its role in offering tolerance against multiple abiotic stresses.

  3. AhpC (alkyl hydroperoxide reductase) from Anabaena sp. PCC 7120 protects Escherichia coli from multiple abiotic stresses

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Yogesh; Chaurasia, Neha [Molecular Biology Section, Laboratory of Algal Biology, Center of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005 (India); Rai, Lal Chand, E-mail: lcraibhu@gmail.com [Molecular Biology Section, Laboratory of Algal Biology, Center of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005 (India)

    2009-04-17

    Alkyl hydroperoxide reductase (AhpC) is known to detoxify peroxides and reactive sulfur species (RSS). However, the relationship between its expression and combating of abiotic stresses is still not clear. To investigate this relationship, the genes encoding the alkyl hydroperoxide reductase (ahpC) from Anabaena sp. PCC 7120 were introduced into E. coli using pGEX-5X-2 vector and their possible functions against heat, salt, carbofuron, cadmium, copper and UV-B were analyzed. The transformed E. coli cells registered significantly increase in growth than the control cells under temperature (47 {sup o}C), NaCl (6% w/v), carbofuron (0.025 mg ml{sup -1}), CdCl{sub 2} (4 mM), CuCl{sub 2} (1 mM), and UV-B (10 min) exposure. Enhanced expression of ahpC gene as measured by semi-quantitative RT-PCR under aforementioned stresses at different time points demonstrated its role in offering tolerance against multiple abiotic stresses.

  4. The Surgically Induced Stress Response

    OpenAIRE

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

    2013-01-01

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

  5. Verification of the resistance of a LEA gene from Tamarix expression in Saccharomyces cerevisiae to abiotic stresses

    Institute of Scientific and Technical Information of China (English)

    WANG Bing-feng; WANG Yu-cheng; ZHANG Da-wei; LI Hong-yan; YANG Chuan-ping

    2008-01-01

    The role of late embryogenesis abundant (LEA) proteins in stress tolerance was examined by using a yeast expression system. LEA protein tolerance to the abotic stresses in plants involved in salt, drought and freezing stresses and additional tolerance to heat, NaHCO3 (salt-alkali) and ultraviolet radiation was also investigated. The transgenic yeast harboring the Tamarix LEA gene (DQ663481) was generated under the control of inducible GAL promoter (pYES2 vector), yeast cells transformed with pYES2 empty vector were also generated as a control. Stress tolerance tests showed that LEA yeast transformants exhibited a higher survival rates than the control transformants under high temperature, NaHCO3, ultraviolet radiation, salt (NaCl), drought and freezing, indicating that the LEA gene is tolerant to these abiotic stresses. These results suggest that the LEA gene is resistant to a wider repertoire of stresses and may play a common role in plant acclimation to the examined stress conditions.

  6. Heterologous expression of the wheat aquaporin gene TaTIP2;2 compromises the abiotic stress tolerance of Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Chunhui Xu

    Full Text Available Aquaporins are channel proteins which transport water across cell membranes. We show that the bread wheat aquaporin gene TaTIP2;2 maps to the long arm of chromosome 7b and that its product localizes to the endomembrane system. The gene is expressed constitutively in both the root and the leaf, and is down-regulated by salinity and drought stress. Salinity stress induced an increased level of C-methylation within the CNG trinucleotides in the TaTIP2;2 promoter region. The heterologous expression of TaTIP2;2 in Arabidopsis thaliana compromised its drought and salinity tolerance, suggesting that TaTIP2;2 may be a negative regulator of abiotic stress. The proline content of transgenic A. thaliana plants fell, consistent with the down-regulation of P5CS1, while the expression of SOS1, SOS2, SOS3, CBF3 and DREB2A, which are all stress tolerance-related genes acting in an ABA-independent fashion, was also down-regulated. The supply of exogenous ABA had little effect either on TaTIP2;2 expression in wheat or on the phenotype of transgenic A. thaliana. The expression level of the ABA signalling genes ABI1, ABI2 and ABF3 remained unaltered in the transgenic A. thaliana plants. Thus TaTIP2;2 probably regulates the response to stress via an ABA-independent pathway(s.

  7. ROLE OF NITRIC OXIDE IN REGULATION OF H2O2 MEDIATING TOLERANCE OF PLANTS TO ABIOTIC STRESS: A SYNERGISTIC SIGNALING APPROACH

    OpenAIRE

    Taqi Ahmed Khan; Mohd Mazid; Firoz Mohammad

    2011-01-01

    The relationship between abiotic stress, nitric oxide (NO) and Hydrogen peroxide (H2O2) is a challenging one. It is now clear that H2O2 and NO function as signaling molecules in plants. A wide range of abiotic stresses results in H2O2 generation, from a variety of sources and it has many essential roles in plant metabolism but at the same time, accumulation related to virtually any environmental stress is potentially damaging. NO is gaining increasing attention as a regulator of diverse patho...

  8. Validation of potential reference genes for qPCR in maize across abiotic stresses, hormone treatments, and tissue types.

    Directory of Open Access Journals (Sweden)

    Yueai Lin

    Full Text Available The reverse transcription quantitative polymerase chain reaction (RT-qPCR is a powerful and widely used technique for the measurement of gene expression. Reference genes, which serve as endogenous controls ensure that the results are accurate and reproducible, are vital for data normalization. To bolster the literature on reference gene selection in maize, ten candidate reference genes, including eight traditionally used internal control genes and two potential candidate genes from our microarray datasets, were evaluated for expression level in maize across abiotic stresses (cold, heat, salinity, and PEG, phytohormone treatments (abscisic acid, salicylic acid, jasmonic acid, ethylene, and gibberellins, and different tissue types. Three analytical software packages, geNorm, NormFinder, and Bestkeeper, were used to assess the stability of reference gene expression. The results revealed that elongation factor 1 alpha (EF1α, tubulin beta (β-TUB, cyclophilin (CYP, and eukaryotic initiation factor 4A (EIF4A were the most reliable reference genes for overall gene expression normalization in maize, while GRP (Glycine-rich RNA-binding protein, GLU1(beta-glucosidase, and UBQ9 (ubiquitin 9 were the least stable and most unsuitable genes. In addition, the suitability of EF1α, β-TUB, and their combination as reference genes was confirmed by validating the expression of WRKY50 in various samples. The current study indicates the appropriate reference genes for the urgent requirement of gene expression normalization in maize across certain abiotic stresses, hormones, and tissue types.

  9. Evaluation of expression stability of candidate references genes among green and yellow pea cultivars (Pisum sativum L.) subjected to abiotic and biotic stress

    Science.gov (United States)

    Dry pea (Pisum sativum) is grown as human and animal feed throughout the world. Large yield losses in pea due to biotic and abiotic stresses compel an improved understanding of mechanisms of stress tolerance and genetic determinants conditioning these tolerances. The availability of stably expressed...

  10. The Surgically Induced Stress Response

    Science.gov (United States)

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

    2013-01-01

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

  11. Multiple abiotic stress tolerance in Vigna mungo is altered by overexpression of ALDRXV4 gene via reactive carbonyl detoxification.

    Science.gov (United States)

    Singh, Preeti; Kumar, Deepak; Sarin, Neera Bhalla

    2016-06-01

    Vigna mungo (blackgram) is an important leguminous pulse crop, which is grown for its protein rich edible seeds. Drought and salinity are the major abiotic stresses which adversely affect the growth and productivity of crop plants including blackgram. The ALDRXV4 belongs to the aldo-keto reductase superfamily of enzymes that catalyze the reduction of carbonyl metabolites in the cells and plays an important role in the osmoprotection and detoxification of the reactive carbonyl species. In the present study, we developed transgenic plants of V. mungo using Agrobacterium mediated transformation. The transgene integration was confirmed by Southern blot analysis whereas the expression was confirmed by RT-PCR, Western blot and enzyme activity. The T1 generation transgenic plants displayed improved tolerance to various environmental stresses, including drought, salt, methyl viologen and H2O2 induced oxidative stress. The increased aldose reductase activity, higher sorbitol content and less accumulation of the toxic metabolite, methylglyoxal in the transgenic lines under non-stress and stress (drought and salinity) conditions resulted in increased protection through maintenance of better photosynthetic efficiency, higher relative water content and less photooxidative damage. The accumulation of reactive oxygen species was remarkably decreased in the transgenic lines as compared with the wild type plants. This study of engineering multiple stress tolerance in blackgram, is the first report to date and this strategy for trait improvement is proposed to provide a novel germplasm for blackgram production on marginal lands.

  12. Overexpression of MuHSP70 gene from Macrotyloma uniflorum confers multiple abiotic stress tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Masand, Shikha; Yadav, Sudesh Kumar

    2016-02-01

    A 70-KD heat shock protein (HSP70) is one of the most conserved chaperones. It is involved in de novo protein folding and prevents the aggregation of unfolded proteins under lethal environmental factors. The purpose of this study is to characterise a MuHSP70 from horsegram (Macrotyloma uniflorum) and elucidating its role in stress tolerance of plants. A MuHSP70 was cloned and characterised from a natural drought stress tolerant HPK4 variety of horsegram (M. uniflorum). For functional characterization, MuHSP70 was overexpressed in transgenic Arabidopsis. Overexpression of MuHSP70 was found to provide tolerance to the transgenic Arabidopsis against various stresses such as heat, cold, drought, salinity and oxidative stress. MuHSP70 transgenics were observed to maintain the shoot biomass, root length, relative water content, and chlorophyll content during exposure to multi-stresses relative to non-transgenic control. Transgenic lines have further shown the reduced levels of MDA, H2O2, and proteolytic activity. Together, these findings suggest that overexpression of MuHSP70 plays an important role in improving abiotic stress tolerance and could be a crucial candidate gene for exploration in crop improvement program. PMID:26694324

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

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    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.

  14. Mutational Analysis to Dissect Oxidative and Abiotic Stress in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    A forward genetics approach was used to identify mutants more tolerant to oxidative stress. Chemically and T-DNA-mutagenized collections of Arabidopsis thaliana mutant lines were screened for survivors under conditions that trigger oxidative stress-induced programmed cell death (PCD). The fungal AAL-toxin triggers PCD through perturbations of sphingolipid metabolism in AAL-toxin-sensitive plants. While Arabidopsis is relatively insensitive to the toxin, the loh2 mutant is sensitive to AAL-toxin due to knockout of a gene involved in sphingolipid metabolism. EMS mutagenesis of loh2 resulted in second-site mutants that are more tolerant than loh2 to the toxin. Nine of these mutants, named atr (AAL-toxin-resistant), were characterized towards their response to oxidative stress-induced cell death. Either application of the catalase inhibitor aminotriazole, leading to H2O2 accumulation was used, or paraquat, leading to superoxide radicals generation. Some mutants were more tolerant to aminotriazole, paraquat, or both herbicides. In another approach, T-DNA mutagenized wild type seeds were germinated on plant growth media supplemented with aminotriazole and one survivor was recovered. Atr1, atr7 and atr9, with tolerance to both aminotriazole and paraquat, were studied in more details. They showed tolerance to paraquat at seedling stage as well as at rosette leaf stage. Atr1 was subjected to microarray analyses at seedling stage under conditions that trigger cell death in loh2 and no visible damage in atr1. While most of the genes showed similar expression pattern in both mutants, some genes were specifically regulated in loh2 or atr1. These specifically regulated genes are potential targets for further functional studies. Downregulation of genes related to cell wall extension and cell growth in both mutants is consistent with the observed AT-induced growth inhibition in both mutants. It indicates that AT-induced oxidative stress influences two different processes: growth

  15. Application of Selected Reaction Monitoring Mass Spectrometry to Field Grown Crop Plants To Allow Dissection of the Molecular Mechanisms of Abiotic Stress Tolerance.

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    Richard P. Jacoby

    2013-02-01

    Full Text Available One major constraint upon the application of molecular crop breeding approaches is the small number of genes linked to agronomically desirable traits through defined biochemical mechanisms. Proteomic investigations of crop plants under abiotic stress treatments have identified many proteins that differ in control versus stress comparisons, however this broad profiling of cell physiology is poorly suited to ranking the effects and identifying the specific proteins that are causative in agronomically relevant traits. Here we will reason that insights into a protein’s function, its biochemical process and links to stress tolerance are more likely to arise through approaches that evaluate these differential abundances of proteins and include varietal comparisons, precise discrimination of protein isoforms, enrichment of functionally related proteins and integration of proteomic datasets with physiological measurements of both lab and field grown plants. We will briefly explain how applying the emerging proteomic technology of multiplexed selective reaction monitoring mass spectrometry with its accuracy and throughput can facilitate and enhance these approaches and provide a clear means to rank the growing cohort of stress responsive proteins. We will also highlight the benefit of integrating proteomic analyses with cultivar-specific genetic databases and physiological assessments of cultivar performance in relevant field environments for revealing deeper insights into molecular crop improvement.

  16. Overexpression of spinach non-symbiotic hemoglobin in Arabidopsis resulted in decreased NO content and lowered nitrate and other abiotic stresses tolerance

    Science.gov (United States)

    Bai, Xuegui; Long, Juan; He, Xiaozhao; Yan, Jinping; Chen, Xuanqin; Tan, Yong; Li, Kunzhi; Chen, Limei; Xu, Huini

    2016-01-01

    A class 1 non-symbiotic hemoglobin family gene, SoHb, was isolated from spinach. qRT-PCR showed that SoHb was induced by excess nitrate, polyethylene glycol, NaCl, H2O2, and salicylic acid. Besides, SoHb was strongly induced by application of nitric oxide (NO) donor, while was suppressed by NO scavenger, nitrate reductase inhibitor, and nitric oxide synthase inhibitor. Overexpression of SoHb in Arabidopsis resulted in decreased NO level and sensitivity to nitrate stress, as shown by reduced root length, fresh weight, the maximum photosystem II quantum ratio of variable to maximum fluorescence (Fv/Fm), and higher malondialdehyde contents. The activities and gene transcription of superoxide dioxidase, and catalase decreased under nitrate stress. Expression levels of RD22, RD29A, DREB2A, and P5CS1 decreased after nitrate treatment in SoHb-overexpressing plants, while increased in the WT plants. Moreover, SoHb-overexpressing plants showed decreased tolerance to NaCl and osmotic stress. In addition, the SoHb-overexpression lines showed earlier flower by regulating the expression of SOC, GI and FLC genes. Our results indicated that the decreasing NO content in Arabidopsis by overexpressing SoHb might be responsible for lowered tolerance to nitrate and other abiotic stresses. PMID:27211528

  17. Housekeeping gene selection for real-time RT-PCR normalization in potato during biotic and abiotic stress.

    Science.gov (United States)

    Nicot, Nathalie; Hausman, Jean-François; Hoffmann, Lucien; Evers, Danièle

    2005-11-01

    Plant stress studies are more and more based on gene expression. The analysis of gene expression requires sensitive, precise, and reproducible measurements for specific mRNA sequences. Real-time RT-PCR is at present the most sensitive method for the detection of low abundance mRNA. To avoid bias, real-time RT-PCR is referred to one or several internal control genes, which should not fluctuate during treatments. Here, the non-regulation of seven housekeeping genes (beta-tubulin, cyclophilin, actin, elongation factor 1-alpha (ef1alpha), 18S rRNA, adenine phosphoribosyl transferase (aprt), and cytoplasmic ribosomal protein L2) during biotic (late blight) and abiotic stresses (cold and salt stress) was tested on potato plants using geNorm software. Results from the three experimental conditions indicated that ef1alpha was the most stable among the seven tested. The expression of the other housekeeping genes tested varied upon stress. In parallel, a study of the variability of expression of hsp20.2, shown to be implicated in late blight stress, was realized. The relative quantification of the hsp20.2 gene varied according to the internal control and the number of internal controls used, thus highlighting the importance of the choice of internal controls in such experiments.

  18. A R2R3-MYB transcription factor from Lablab purpureus induced by drought increases tolerance to abiotic stress in Arabidopsis.

    Science.gov (United States)

    Yao, Luming; Jiang, Yina; Lu, Xinxin; Wang, Biao; Zhou, Pei; Wu, Tianlong

    2016-10-01

    Few regulators for drought tolerance have been identified in Lablab purpureus which is a multipurpose leguminous crop. The transcription factor MYB is involved in regulatory networks in response to abiotic and biotic stresses in plants. A novel R2R3-MYB factor in L. purpureus has been identified. An suppression subtraction hybridization (SSH) library was constructed using root tissues of L. purpureus MEIDOU 2012 from well-watered and water-stress treatments that were subjected to drought stress for 10 days. In addition, the cDNA of LpMYB1 was identified based on the SSH library. The cDNA of LpMYB1 is 858 bp and encodes a 285-amino acid protein with a calculated mass of 33.4 kDa. The LpMYB1 protein localizes to the nucleus and has transactivation activity with the activation domain in the C terminal region of the protein. In LpMYB1 overexpressed Arabidopsis, the tolerance of transgenic seedlings to drought and salt was improved, and the germination potential of transgenic seeds increase in the presence of NaCl or ABA. LpMYB1 is a drought-responsive R2R3-MYB factor that can increase the drought and salt tolerance of LpMYB1-overexpressed Arabidopsis. PMID:27565983

  19. 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

  20. Evaluation of candidate reference genes for normalization of quantitative RT-PCR in soybean tissues under various abiotic stress conditions.

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    Dung Tien Le

    Full Text Available Quantitative RT-PCR can be a very sensitive and powerful technique for measuring differential gene expression. Changes in gene expression induced by abiotic stresses are complex and multifaceted, which make determining stably expressed genes for data normalization difficult. To identify the most suitable reference genes for abiotic stress studies in soybean, 13 candidate genes collected from literature were evaluated for stability of expression under dehydration, high salinity, cold and ABA (abscisic acid treatments using delta CT and geNorm approaches. Validation of reference genes indicated that the best reference genes are tissue- and stress-dependent. With respect to dehydration treatment, the Fbox/ABC, Fbox/60s gene pairs were found to have the highest expression stability in the root and shoot tissues of soybean seedlings, respectively. Fbox and 60s genes are the most suitable reference genes across dehydrated root and shoot tissues. Under salt stress the ELF1b/IDE and Fbox/ELF1b are the most stably expressed gene pairs in roots and shoots, respectively, while 60s/Fbox is the best gene pair in both tissues. For studying cold stress in roots or shoots, IDE/60s and Fbox/Act27 are good reference gene pairs, respectively. With regard to gene expression analysis under ABA treatment in either roots, shoots or across these tissues, 60s/ELF1b, ELF1b/Fbox and 60s/ELF1b are the most suitable reference genes, respectively. The expression of ELF1b/60s, 60s/Fbox and 60s/Fbox genes was most stable in roots, shoots and both tissues, respectively, under various stresses studied. Among the genes tested, 60s was found to be the best reference gene in different tissues and under various stress conditions. The highly ranked reference genes identified from this study were proved to be capable of detecting subtle differences in expression rates that otherwise would be missed if a less stable reference gene was used.

  1. 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...... include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review...... the responses of neurons to various physiological stressors at the molecular and cellular level....

  2. Normalization for Relative Quantification of mRNA and microRNA in Soybean Exposed to Various Abiotic Stresses.

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    Weican Liu

    Full Text Available Plant microRNAs are small non-coding, endogenic RNA molecule (containing 20-24 nucleotides produced from miRNA precursors (pri-miRNA and pre-miRNA. Evidence suggests that up and down regulation of the miRNA targets the mRNA genes involved in resistance against biotic and abiotic stresses. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR is a powerful technique to analyze variations in mRNA levels. Normalizing the data using reference genes is essential for the analysis of reliable RT-qPCR data. In this study, two groups of candidate reference mRNAs and miRNAs in soybean leaves and roots treated with various abiotic stresses (PEG-simulated drought, salinity, alkalinity, salinity+alkalinity, and abscisic acid were analyzed by RT-qPCR. We analyzed the most appropriate reference mRNA/miRNAs using the geNorm, NormFinder, and BestKeeper algorithms. According to the results, Act and EF1b were the most suitable reference mRNAs in leaf and root samples, for mRNA and miRNA precursor data normalization. The most suitable reference miRNAs found in leaf and root samples were 166a and 167a for mature miRNA data normalization. Hence the best combinations of reference mRNAs for mRNA and miRNA precursor data normalization were EF1a + Act or EF1b + Act in leaf samples, and EF1a + EF1b or 60s + EF1b in root samples. For mature miRNA data normalization, the most suitable combinations of reference miRNAs were 166a + 167d in leaf samples, and 171a + 156a or 167a + 171a in root samples. We identified potential reference mRNA/miRNAs for accurate RT-qPCR data normalization for mature miRNA, miRNA precursors, and their targeted mRNAs. Our results promote miRNA-based studies on soybean plants exposed to abiotic stress conditions.

  3. 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.

  4. Genome-wide identification and expression profiling analysis of ZmPIN, ZmPILS, ZmLAX and ZmABCB auxin transporter gene families in maize (Zea mays L. under various abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Runqing Yue

    Full Text Available The auxin influx carriers auxin resistant 1/like aux 1 (AUX/LAX, efflux carriers pin-formed (PIN (together with PIN-like proteins and efflux/conditional P-glycoprotein (ABCB are major protein families involved in auxin polar transport. However, how they function in responses to exogenous auxin and abiotic stresses in maize is largely unknown. In this work, the latest updated maize (Zea mays L. reference genome sequence was used to characterize and analyze the ZmLAX, ZmPIN, ZmPILS and ZmABCB family genes from maize. The results showed that five ZmLAXs, fifteen ZmPINs, nine ZmPILSs and thirty-five ZmABCBs were mapped on all ten maize chromosomes. Highly diversified gene structures, nonconservative transmembrane helices and tissue-specific expression patterns suggested the possibility of function diversification for these genes. Quantitative real-time polymerase chain reaction (qRT-PCR was used to analyze the expression patterns of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes under exogenous auxin and different environmental stresses. The expression levels of most ZmPIN, ZmPILS, ZmLAX and ZmABCB genes were induced in shoots and were reduced in roots by various abiotic stresses (drought, salt and cold stresses. The opposite expression response patterns indicated the dynamic auxin transport between shoots and roots under abiotic stresses. Analysis of the expression patterns of ZmPIN, ZmPILS, ZmLAX and ZmABCB genes under drought, salt and cold treatment may help us to understand the possible roles of maize auxin transporter genes in responses and tolerance to environmental stresses.

  5. The persimmon 9-lipoxygenase gene DkLOX3 plays positive roles in both promoting senescence and enhancing tolerance to abiotic stress

    Directory of Open Access Journals (Sweden)

    Yali eHou

    2015-12-01

    Full Text Available The lipoxygenase (LOX pathway is a key regulator for lipid peroxidation, which is crucial for plant senescence and defence pathways. In this study, the transcriptional expression patterns of three persimmon (Diospyros kaki L. ‘Fupingjianshi’ 9-lipoxygenase genes (DkLOX1, DkLOX3 and DkLOX4 were investigated. DkLOX1 was specifically expressed in fruit, particularly in young fruit, and showed little response to the postharvest environments. DkLOX4 was expressed in all tissues and slightly stimulated by mechanical damage and low temperature. DkLOX3 was expressed mainly in mature fruit, and the expression was extremely high throughout the storage period, apparently up-regulated by mechanical damage and high carbon dioxide treatments. Further functional analysis showed that overexpression of DkLOX3 in tomato (Solanum lycopersicum cv. Micro-Tom accelerated fruit ripening and softening. This was accompanied by higher MDA content and lycopene accumulation, advanced ethylene release peak and elevated expression of ethylene synthesis genes, including ACS2, ACO1 and ACO3. In addition, DkLOX3 overexpression promoted dark induced transgenic Arabidopsis leaf senescence with more chlorophyll loss, increased electrolyte leakage and MDA content. Furthermore, the functions of DkLOX3 in response to abiotic stresses, including osmotic stress, high salinity and drought were investigated. Arabidopsis DkLOX3-OX transgenic lines were found to be more tolerant to osmotic stress with higher germination rate and root growth than wild-type. Moreover, DkLOX3-OX Arabidopsis plants also exhibited enhanced resistance to high salinity and drought, with similar decreased O2- and H2O2 accumulation and upregulation of stress-responsive genes expression, including RD22, RD29A, RD29B and NCED3, except for FRY1, which plays a negative role in stress response. Overall, these results suggested that DkLOX3 plays positive roles both in promoting ripening and senescence through lipid

  6. Environmental Association Analyses Identify Candidates for Abiotic Stress Tolerance in Glycine soja, the Wild Progenitor of Cultivated Soybeans.

    Science.gov (United States)

    Anderson, Justin E; Kono, Thomas J Y; Stupar, Robert M; Kantar, Michael B; Morrell, Peter L

    2016-04-07

    Natural populations across a species range demonstrate population structure owing to neutral processes such as localized origins of mutations and migration limitations. Selection also acts on a subset of loci, contributing to local adaptation. An understanding of the genetic basis of adaptation to local environmental conditions is a fundamental goal in basic biological research. When applied to crop wild relatives, this same research provides the opportunity to identify adaptive genetic variation that may be used to breed for crops better adapted to novel or changing environments. The present study explores an ex situ conservation collection, the USDA germplasm collection, genotyped at 32,416 SNPs to identify population structure and test for associations with bioclimatic and biophysical variables in Glycine soja, the wild progenitor of Glycine max (soybean). Candidate loci were detected that putatively contribute to adaptation to abiotic stresses. The identification of potentially adaptive variants in this ex situ collection may permit a more targeted use of germplasm collections.

  7. Neuronal responses to physiological stress

    Directory of Open Access Journals (Sweden)

    Konstantinos eKagias

    2012-10-01

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

  8. The SbMT-2 gene from a halophyte confers abiotic stress tolerance and modulates ROS scavenging in transgenic tobacco.

    Directory of Open Access Journals (Sweden)

    Amit Kumar Chaturvedi

    Full Text Available Heavy metals are common pollutants of the coastal saline area and Salicornia brachiata an extreme halophyte is frequently exposed to various abiotic stresses including heavy metals. The SbMT-2 gene was cloned and transformed to tobacco for the functional validation. Transgenic tobacco lines (L2, L4, L6 and L13 showed significantly enhanced salt (NaCl, osmotic (PEG and metals (Zn++, Cu++ and Cd++ tolerance compared to WT plants. Transgenic lines did not show any morphological variation and had enhanced growth parameters viz. shoot length, root length, fresh weight and dry weight. High seed germination percentage, chlorophyll content, relative water content, electrolytic leakage and membrane stability index confirmed that transgenic lines performed better under salt (NaCl, osmotic (PEG and metals (Zn++, Cu++ and Cd++ stress conditions compared to WT plants. Proline, H2O2 and lipid peroxidation (MDA analyses suggested the role of SbMT-2 in cellular homeostasis and H2O2 detoxification. Furthermore in vivo localization of H2O2 and O2-; and elevated expression of key antioxidant enzyme encoding genes, SOD, POD and APX evident the possible role of SbMT-2 in ROS scavenging/detoxification mechanism. Transgenic lines showed accumulation of Cu++ and Cd++ in root while Zn++ in stem under stress condition. Under control (unstressed condition, Zn++ was accumulated more in root but accumulation of Zn++ in stem under stress condition suggested that SbMT-2 may involve in the selective translocation of Zn++ from root to stem. This observation was further supported by the up-regulation of zinc transporter encoding genes NtZIP1 and NtHMA-A under metal ion stress condition. The study suggested that SbMT-2 modulates ROS scavenging and is a potential candidate to be used for phytoremediation and imparting stress tolerance.

  9. Wheat chloroplast targeted sHSP26 promoter confers heat and abiotic stress inducible expression in transgenic Arabidopsis Plants.

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    Neetika Khurana

    Full Text Available The small heat shock proteins (sHSPs have been found to play a critical role in physiological stress conditions in protecting proteins from irreversible aggregation. To characterize the hloroplast targeted sHSP26 promoter in detail, deletion analysis of the promoter is carried out and analysed via transgenics in Arabidopsis. In the present study, complete assessment of the importance of CCAAT-box elements along with Heat shock elements (HSEs in the promoter of sHSP26 was performed. Moreover, the importance of 5' untranslated region (UTR has also been established in the promoter via Arabidopsis transgenics. An intense GUS expression was observed after heat stress in the transgenics harbouring a full-length promoter, confirming the heat-stress inducibility of the promoter. Transgenic plants without UTR showed reduced GUS expression when compared to transgenic plants with UTR as was confirmed at the RNA and protein levels by qRT-PCR and GUS histochemical assays, thus suggesting the possible involvement of some regulatory elements present in the UTR in heat-stress inducibility of the promoter. Promoter activity was also checked under different abiotic stresses and revealed differential expression in different deletion constructs. Promoter analysis based on histochemical assay, real-time qPCR and fluorimetric analysis revealed that HSEs alone could not transcribe GUS gene significantly in sHSP26 promoter and CCAAT box elements contribute synergistically to the transcription. Our results also provide insight into the importance of 5`UTR of sHsp26 promoter thus emphasizing the probable role of imperfect CCAAT-box element or some novel cis-element with respect to heat stress.

  10. ‘In silico expression analysis’, a novel PathoPlant web tool to identify abiotic and biotic stress conditions associated with specific cis-regulatory sequences

    Science.gov (United States)

    Machens, Fabian; Brill, Yuri; Romanov, Artyom; Bülow, Lorenz; Hehl, Reinhard

    2014-01-01

    Using bioinformatics, putative cis-regulatory sequences can be easily identified using pattern recognition programs on promoters of specific gene sets. The abundance of predicted cis-sequences is a major challenge to associate these sequences with a possible function in gene expression regulation. To identify a possible function of the predicted cis-sequences, a novel web tool designated ‘in silico expression analysis’ was developed that correlates submitted cis-sequences with gene expression data from Arabidopsis thaliana. The web tool identifies the A. thaliana genes harbouring the sequence in a defined promoter region and compares the expression of these genes with microarray data. The result is a hierarchy of abiotic and biotic stress conditions to which these genes are most likely responsive. When testing the performance of the web tool, known cis-regulatory sequences were submitted to the ‘in silico expression analysis’ resulting in the correct identification of the associated stress conditions. When using a recently identified novel elicitor-responsive sequence, a WT-box (CGACTTTT), the ‘in silico expression analysis’ predicts that genes harbouring this sequence in their promoter are most likely Botrytis cinerea induced. Consistent with this prediction, the strongest induction of a reporter gene harbouring this sequence in the promoter is observed with B. cinerea in transgenic A. thaliana. Database URL: http://www.pathoplant.de/expression_analysis.php. PMID:24727366

  11. 'In silico expression analysis', a novel PathoPlant web tool to identify abiotic and biotic stress conditions associated with specific cis-regulatory sequences.

    Science.gov (United States)

    Bolívar, Julio C; Machens, Fabian; Brill, Yuri; Romanov, Artyom; Bülow, Lorenz; Hehl, Reinhard

    2014-01-01

    Using bioinformatics, putative cis-regulatory sequences can be easily identified using pattern recognition programs on promoters of specific gene sets. The abundance of predicted cis-sequences is a major challenge to associate these sequences with a possible function in gene expression regulation. To identify a possible function of the predicted cis-sequences, a novel web tool designated 'in silico expression analysis' was developed that correlates submitted cis-sequences with gene expression data from Arabidopsis thaliana. The web tool identifies the A. thaliana genes harbouring the sequence in a defined promoter region and compares the expression of these genes with microarray data. The result is a hierarchy of abiotic and biotic stress conditions to which these genes are most likely responsive. When testing the performance of the web tool, known cis-regulatory sequences were submitted to the 'in silico expression analysis' resulting in the correct identification of the associated stress conditions. When using a recently identified novel elicitor-responsive sequence, a WT-box (CGACTTTT), the 'in silico expression analysis' predicts that genes harbouring this sequence in their promoter are most likely Botrytis cinerea induced. Consistent with this prediction, the strongest induction of a reporter gene harbouring this sequence in the promoter is observed with B. cinerea in transgenic A. thaliana. DATABASE URL: http://www.pathoplant.de/expression_analysis.php. PMID:24727366

  12. Functional characterization of Arabidopsis NaCl-inducible WRKY25 and WRKY33 transcription factors in abiotic stresses.

    Science.gov (United States)

    Jiang, Yuanqing; Deyholos, Michael K

    2009-01-01

    Previous microarray analyses of Arabidopsis roots identified two closely related WRKY transcription factors (WRKY25 and WRKY33) among the transcripts that increased in abundance following treatment with NaCl. Here, we report further characterization of these genes, which we found to be inducible by a variety of abiotic stresses in an SOS-pathway independent manner, although WRKY33 induction was dependent on ABA signaling. Transcripts of both genes were detected in roots and leaves, while specific patterns of enrichment were observed in stems and floral buds for WRKY25 and WRKY33, respectively. We also identified upstream intergenic regions from each gene that were sufficient to confer stress-inducible expression on a reporter gene. However, the stress sensitivity of wrky25 null mutants did not differ from wild-type under any assay condition, while wrky33 null mutants and wrky25wrky33 double mutants showed only a moderate increase in NaCl-sensitivity, suggesting functional redundancy with other transcription factors. Nevertheless, overexpression of WRKY25 or WRKY33 was sufficient to increase Arabidopsis NaCl tolerance, while increasing sensitivity to ABA. Through microarray analyses of relevant genotypes, we identified 31 and 208 potential downstream targets of WRKY25 and WRKY33, respectively, most of which contained a W-box in their upstream regions.

  13. Neuronal responses to physiological stress.

    Science.gov (United States)

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

    2012-01-01

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

  14. Heterologous Expression of MeLEA3: A 10 kDa Late Embryogenesis Abundant Protein of Cassava, Confers Tolerance to Abiotic Stress in Escherichia coli with Recombinant Protein Showing In Vitro Chaperone Activity.

    Science.gov (United States)

    Barros, Nicolle L F; da Silva, Diehgo T; Marques, Deyvid N; de Brito, Fabiano M; dos Reis, Savio P; de Souza, Claudia R B

    2015-01-01

    Late embryogenesis abundant (LEA) proteins are small molecular weight proteins involved in acquisition of tolerance to drought, salinity, high temperature, cold, and freezing stress in many plants. Previous studies revealed a cDNA sequence coding for a 10 kDa atypical LEA protein, named MeLEA3, predicted to be located into mitochondria with potential role in salt stress response of cassava (Manihot esculenta Crantz). Here we aimed to produce the recombinant MeLEA3 protein by heterologous expression in Escherichia coli and evaluate the tolerance of bacteria expressing this protein under abiotic stress. Our result revealed that the recombinant MeLEA3 protein conferred a protective function against heat and salt stress in bacterial cells. Also, the recombinant MeLEA3 protein showed in vitro chaperone activity by protection of NdeI restriction enzyme activity under heat stress. PMID:25990084

  15. Proteome Analysis for Understanding Abiotic Stress (Salinity and Drought Tolerance in Date Palm (Phoenix dactylifera L.

    Directory of Open Access Journals (Sweden)

    Haddad A. El Rabey

    2015-01-01

    Full Text Available This study was carried out to study the proteome of date palm under salinity and drought stress conditions to possibly identify proteins involved in stress tolerance. For this purpose, three-month-old seedlings of date palm cultivar “Sagie” were subjected to drought (27.5 g/L polyethylene glycol 6000 and salinity stress conditions (16 g/L NaCl for one month. DIGE analysis of protein extracts identified 47 differentially expressed proteins in leaves of salt- and drought-treated palm seedlings. Mass spectrometric analysis identified 12 proteins; three out of them were significantly changed under both salt and drought stress, while the other nine were significantly changed only in salt-stressed plants. The levels of ATP synthase alpha and beta subunits, an unknown protein and some of RubisCO fragments were significantly changed under both salt and drought stress conditions. Changes in abundance of superoxide dismutase, chlorophyll A-B binding protein, light-harvesting complex1 protein Lhca1, RubisCO activase, phosphoglycerate kinase, chloroplast light-harvesting chlorophyll a/b-binding protein, phosphoribulokinase, transketolase, RubisCO, and some of RubisCO fragments were significant only for salt stress.

  16. Developing fiber specific promoter-reporter transgenic lines to study the effect of abiotic stresses on fiber development in cotton.

    Directory of Open Access Journals (Sweden)

    Junping Chen

    Full Text Available Cotton is one of the most important cash crops in US agricultural industry. Environmental stresses, such as drought, high temperature and combination of both, not only reduce the overall growth of cotton plants, but also greatly decrease cotton lint yield and fiber quality. The impact of environmental stresses on fiber development is poorly understood due to technical difficulties associated with the study of developing fiber tissues and lack of genetic materials to study fiber development. To address this important question and provide the need for scientific community, we have generated transgenic cotton lines harboring cotton fiber specific promoter (CFSP-reporter constructs from six cotton fiber specific genes (Expansin, E6, Rac13, CelA1, LTP, and Fb late, representing genes that are expressed at different stages of fiber development. Individual CFSP::GUS or CFSP::GFP construct was introduced into Coker 312 via Agrobacterium mediated transformation. Transgenic cotton lines were evaluated phenotypically and screened for the presence of selectable marker, reporter gene expression, and insertion numbers. Quantitative analysis showed that the patterns of GUS reporter gene activity during fiber development in transgenic cotton lines were similar to those of the native genes. Greenhouse drought and heat stress study showed a correlation between the decrease in promoter activities and decrease in fiber length, increase in micronaire and changes in other fiber quality traits in transgenic lines grown under stressed condition. These newly developed materials provide new molecular tools for studying the effects of abiotic stresses on fiber development and may be used in study of cotton fiber development genes and eventually in the genetic manipulation of fiber quality.

  17. Enhanced Tolerance of Transgenic Potato Plants Over-Expressing Non-specific Lipid Transfer Protein-1 (StnsLTP1) against Multiple Abiotic Stresses.

    Science.gov (United States)

    Gangadhar, Baniekal H; Sajeesh, Kappachery; Venkatesh, Jelli; Baskar, Venkidasamy; Abhinandan, Kumar; Yu, Jae W; Prasad, Ram; Mishra, Raghvendra K

    2016-01-01

    Abiotic stresses such as heat, drought, and salinity are major environmental constraints that limit potato (Solanum tuberosum L.) production worldwide. Previously, we found a potential thermo-tolerance gene, named StnsLTP1 from potato using yeast functional screening. Here, we report the functional characterization of StnsLTP1 and its role in multiple abiotic stresses in potato plants. Computational analysis of StnsLTP1 with other plant LTPs showed eight conserved cysteine residues, and four α-helices stabilized by four disulfide bridges. Expression analysis of StnsLTP1 gene showed differential expression under heat, water-deficit and salt stresses. Transgenic potato lines over-expressing StnsLTP1 gene displayed enhanced cell membrane integrity under stress conditions, as indicated by reduced membrane lipid per-oxidation, and hydrogen peroxide content relative to untransformed (UT) control plants. In addition, transgenic lines over-expressing StLTP1 also exhibited increased antioxidant enzyme activity with enhanced accumulation of ascorbates, and up-regulation of stress-related genes including StAPX, StCAT, StSOD, StHsfA3, StHSP70, and StsHSP20 compared with the UT plants. These results suggests that StnsLTP1 transgenic plants acquired improved tolerance to multiple abiotic stresses through enhanced activation of antioxidative defense mechanisms via cyclic scavenging of reactive oxygen species and regulated expression of stress-related genes.

  18. Enhanced Tolerance of Transgenic Potato Plants Over-Expressing Non-specific Lipid Transfer Protein-1 (StnsLTP1) against Multiple Abiotic Stresses

    Science.gov (United States)

    Gangadhar, Baniekal H.; Sajeesh, Kappachery; Venkatesh, Jelli; Baskar, Venkidasamy; Abhinandan, Kumar; Yu, Jae W.; Prasad, Ram; Mishra, Raghvendra K.

    2016-01-01

    Abiotic stresses such as heat, drought, and salinity are major environmental constraints that limit potato (Solanum tuberosum L.) production worldwide. Previously, we found a potential thermo-tolerance gene, named StnsLTP1 from potato using yeast functional screening. Here, we report the functional characterization of StnsLTP1 and its role in multiple abiotic stresses in potato plants. Computational analysis of StnsLTP1 with other plant LTPs showed eight conserved cysteine residues, and four α-helices stabilized by four disulfide bridges. Expression analysis of StnsLTP1 gene showed differential expression under heat, water-deficit and salt stresses. Transgenic potato lines over-expressing StnsLTP1 gene displayed enhanced cell membrane integrity under stress conditions, as indicated by reduced membrane lipid per-oxidation, and hydrogen peroxide content relative to untransformed (UT) control plants. In addition, transgenic lines over-expressing StLTP1 also exhibited increased antioxidant enzyme activity with enhanced accumulation of ascorbates, and up-regulation of stress-related genes including StAPX, StCAT, StSOD, StHsfA3, StHSP70, and StsHSP20 compared with the UT plants. These results suggests that StnsLTP1 transgenic plants acquired improved tolerance to multiple abiotic stresses through enhanced activation of antioxidative defense mechanisms via cyclic scavenging of reactive oxygen species and regulated expression of stress-related genes. PMID:27597854

  19. Enhanced Tolerance of Transgenic Potato Plants Over-Expressing Non-specific Lipid Transfer Protein-1 (StnsLTP1) against Multiple Abiotic Stresses.

    Science.gov (United States)

    Gangadhar, Baniekal H; Sajeesh, Kappachery; Venkatesh, Jelli; Baskar, Venkidasamy; Abhinandan, Kumar; Yu, Jae W; Prasad, Ram; Mishra, Raghvendra K

    2016-01-01

    Abiotic stresses such as heat, drought, and salinity are major environmental constraints that limit potato (Solanum tuberosum L.) production worldwide. Previously, we found a potential thermo-tolerance gene, named StnsLTP1 from potato using yeast functional screening. Here, we report the functional characterization of StnsLTP1 and its role in multiple abiotic stresses in potato plants. Computational analysis of StnsLTP1 with other plant LTPs showed eight conserved cysteine residues, and four α-helices stabilized by four disulfide bridges. Expression analysis of StnsLTP1 gene showed differential expression under heat, water-deficit and salt stresses. Transgenic potato lines over-expressing StnsLTP1 gene displayed enhanced cell membrane integrity under stress conditions, as indicated by reduced membrane lipid per-oxidation, and hydrogen peroxide content relative to untransformed (UT) control plants. In addition, transgenic lines over-expressing StLTP1 also exhibited increased antioxidant enzyme activity with enhanced accumulation of ascorbates, and up-regulation of stress-related genes including StAPX, StCAT, StSOD, StHsfA3, StHSP70, and StsHSP20 compared with the UT plants. These results suggests that StnsLTP1 transgenic plants acquired improved tolerance to multiple abiotic stresses through enhanced activation of antioxidative defense mechanisms via cyclic scavenging of reactive oxygen species and regulated expression of stress-related genes. PMID:27597854

  20. A novel Glycine soja tonoplast intrinsic protein gene responds to abiotic stress and depresses salt and dehydration tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Xi; Li, Yong; Ji, Wei; Bai, Xi; Cai, Hua; Zhu, Dan; Sun, Xiao-Li; Chen, Lian-Jiang; Zhu, Yan-Ming

    2011-07-15

    Tonoplast intrinsic protein (TIP) is a subfamily of the aquaporin (AQP), also known as major intrinsic protein (MIP) family, and regulates water movement across vacuolar membranes. Some reports have implied that TIP genes are associated with plant tolerance to some abiotic stresses that cause water loss, such as drought and high salinity. In our previous work, we found that an expressed sequence tag (EST) representing a TIP gene in our Glycine soja EST library was inducible by abiotic stresses. This TIP was subsequently isolated from G. soja with cDNA library screening, EST assembly and PCR, and named as GsTIP2;1. The expression patterns of GsTIP2;1 in G. soja under low temperature, salt and dehydration stress were different in leaves and roots. Though GsTIP2;1 is a stress-induced gene, overexpression of GsTIP2;1 in Arabidopsis thaliana depressed tolerance to salt and dehydration stress, but did not affect seedling growth under cold or favorable conditions. Higher dehydration speed was detected in Arabidopsis plants overexpressing GsTIP2;1, implying GsTIP2;1 might mediate stress sensitivity by enhancing water loss in the plant. Such a result is not identical to previous reports, providing some new information about the relationship between TIP and plant abiotic stress tolerance.

  1. 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.

  2. 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.

  3. 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. PMID:26397813

  4. Modeling regeneration responses of big sagebrush (Artemisia tridentata) to abiotic conditions

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Ecosystems dominated by big sagebrush, Artemisia tridentata Nuttall (Asteraceae), which are the most widespread ecosystems in semiarid western North America, have been affected by land use practices and invasive species. Loss of big sagebrush and the decline of associated species, such as greater sage-grouse, are a concern to land managers and conservationists. However, big sagebrush regeneration remains difficult to achieve by restoration and reclamation efforts and there is no regeneration simulation model available. We present here the first process-based, daily time-step, simulation model to predict yearly big sagebrush regeneration including relevant germination and seedling responses to abiotic factors. We estimated values, uncertainty, and importance of 27 model parameters using a total of 1435 site-years of observation. Our model explained 74% of variability of number of years with successful regeneration at 46 sites. It also achieved 60% overall accuracy predicting yearly regeneration success/failure. Our results identify specific future research needed to improve our understanding of big sagebrush regeneration, including data at the subspecies level and improved parameter estimates for start of seed dispersal, modified wet thermal-time model of germination, and soil water potential influences. We found that relationships between big sagebrush regeneration and climate conditions were site specific, varying across the distribution of big sagebrush. This indicates that statistical models based on climate are unsuitable for understanding range-wide regeneration patterns or for assessing the potential consequences of changing climate on sagebrush regeneration and underscores the value of this process-based model. We used our model to predict potential regeneration across the range of sagebrush ecosystems in the western United States, which confirmed that seedling survival is a limiting factor, whereas germination is not. Our results also suggested that modeled

  5. The Critical Role of Potassium in Plant Stress Response

    OpenAIRE

    Min Wang; Qingsong Zheng; Qirong Shen; Shiwei Guo

    2013-01-01

    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 stres...

  6. Specific roles of tocopherols and tocotrienols in seed longevity and germination tolerance to abiotic stress in transgenic rice.

    Science.gov (United States)

    Chen, Defu; Li, Yanlan; Fang, Tao; Shi, Xiaoli; Chen, Xiwen

    2016-03-01

    Tocopherols and tocotrienols are lipophilic antioxidants that are abundant in plant seeds. Although their roles have been extensively studied, our understanding of their functions in rice seeds is still limited. In this study, on the basis of available RNAi rice plants constitutively silenced for homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC), we developed transgenic plants that silenced homogentisate geranylgeranyl transferase (HGGT). All the RNAi plants showed significantly reduced germination percentages and a higher proportion of abnormal seedlings than the control plants, with HGGT transgenics showing the most severe phenotype. The accelerated aging phenotype corresponded well with the amount of H2O2 accumulated in the embryo, glucose level, and ion leakage, but not with the amount of O(2-) accumulated in the embryo and lipid hydroperoxides levels in these genotypes. Under abiotic stress conditions, HPT and TC transgenics showed lower germination percentage and seedling growth than HGGT transgenics, while HGGT transgenics showed almost the same status as the wild type. Therefore, we proposed that tocopherols in the germ may protect the embryo from reactive oxygen species under both accelerated aging and stress conditions, whereas tocotrienols in the pericarp may exclusively help in reducing the metabolic activity of the seed during accelerated aging.

  7. Specific roles of tocopherols and tocotrienols in seed longevity and germination tolerance to abiotic stress in transgenic rice.

    Science.gov (United States)

    Chen, Defu; Li, Yanlan; Fang, Tao; Shi, Xiaoli; Chen, Xiwen

    2016-03-01

    Tocopherols and tocotrienols are lipophilic antioxidants that are abundant in plant seeds. Although their roles have been extensively studied, our understanding of their functions in rice seeds is still limited. In this study, on the basis of available RNAi rice plants constitutively silenced for homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC), we developed transgenic plants that silenced homogentisate geranylgeranyl transferase (HGGT). All the RNAi plants showed significantly reduced germination percentages and a higher proportion of abnormal seedlings than the control plants, with HGGT transgenics showing the most severe phenotype. The accelerated aging phenotype corresponded well with the amount of H2O2 accumulated in the embryo, glucose level, and ion leakage, but not with the amount of O(2-) accumulated in the embryo and lipid hydroperoxides levels in these genotypes. Under abiotic stress conditions, HPT and TC transgenics showed lower germination percentage and seedling growth than HGGT transgenics, while HGGT transgenics showed almost the same status as the wild type. Therefore, we proposed that tocopherols in the germ may protect the embryo from reactive oxygen species under both accelerated aging and stress conditions, whereas tocotrienols in the pericarp may exclusively help in reducing the metabolic activity of the seed during accelerated aging. PMID:26810451

  8. Abscisic Acid-mediated Epigenetic Processes in Plant Development and Stress Responses

    Institute of Scientific and Technical Information of China (English)

    Viswanathan Chinnusamy; Zhizhong Gong; Jian-Kang Zhu

    2008-01-01

    Abscisic acid (ABA) regulates diverse plant processes, growth and development under non-stress conditions and plays a pivotal role in abiotic stress tolerance. Although ABA-regulated genetic processes are well known, recent discoveries reveal that epigenetic processes are an integral part of ABA-regulated processes. Epigenetic mechanisms, namely, histone modifications and cytosine DNA methylation-induced modification of genome give rise to epigenomes, which add diversity and complexity to the genome of organisms. Histone monoubiquitination appears to regulate ABA levels in developing seeds through histone H2B monoubiquitination. ABA and H2B ubiquitination dependent chromatin remodeling regulate seed dormancy. Transcription factor networks necessary for seed maturation are repressed by histone deacetylases (HDACs)-dependent and PICKLE chromatin remodeling complexes (CRCs), whereas ABA induces the expression of these genes directly or through repression of HDACs. Abiotic stress-induced ABA regulates stomatal response and stress-responsive gene expression through HDACs and HOS15-dependent histone deacetylation, as well as through the ATP-dependent SWITCH/SUCROSE NONFERMENTING CRC. ABA also probably regulates the abiotic stress response through DNA methylation and short interfering RNA pathways. Further studies on ABA-regulated spigenome will be of immense use to understand the plant development, stress adaptation and stress memory.

  9. A hormone-responsive C1-domain-containing protein At5g17960 mediates stress response in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Ravindran Vijay Bhaskar

    Full Text Available Phytohormones play a critical role in mediating plant stress response. They employ a variety of proteins for coordinating such processes. In Arabidopsis thaliana, some members of a Cys-rich protein family known as C1-clan proteins were involved in stress response, but the actual function of the protein family is largely unknown. We studied At5g17960, a C1-clan protein member that possesses three unique C1 signature domains viz. C1_2, C1_3 and ZZ/PHD type. Additionally, we identified 72 other proteins in A. thaliana that contain all three unique signature domains. Subsequently, the 73 proteins were phylogenetically classified into IX subgroups. Promoter motif analysis of the 73 genes identified the presence of hormone-responsive and stress-responsive putative cis-regulatory elements. Furthermore, we observed that transcript levels of At5g17960 were induced in response to different hormones and stress treatments. At1g35610 and At3g13760, two other members of subgroup IV, also showed upregulation upon GA3, biotic and abiotic stress treatments. Moreover, seedlings of independent transgenic A. thaliana lines ectopically expressing or suppressing At5g17960 also showed differential regulation of several abiotic stress-responsive marker genes. Thus, our data suggest that C1-domain-containing proteins have a role to play in plant hormone-mediated stress responses, thereby assigning a putative function for the C1-clan protein family.

  10. Evaluation and Characterization of Mutant Cowpea Plants for Enhanced Abiotic Stress Tolerance

    International Nuclear Information System (INIS)

    The objective of the project is to use the radiation-induced mutations in cowpea to improve cowpea varieties grown by resource-poor farmers in South Africa. The first aim of the project was to select mutant cowpea plants with improved levels of drought tolerance without alteration to the color of the testa or the growth form. It was demonstrated that it was possible to examine mutant lines at seedling stage in wooden boxes. Mature plants were screened in rain out shelters and physiological traits for drought stress were identified among the lines tested. Roots of mature plants were also assessed and variations observed could be correlated with drought tolerance. The data demonstrated that physiological methods can be used to screen mutants. The yield performance of some mutant lines proved to be outstanding under well-watered, as well as under drought stress conditions. The second aim was to further characterize the most promising mutant lines using molecular and physiological techniques. cDNA-Amplified Fragment Length Polymorphism showed differential gene expression at different time points of drought stress. The sequenced transcript derived fragments (TDF) showed high homology to expressed sequence tags of soybean, with a possible function in cell defense/resistance and most importantly, signal transduction. Reverse transcription PCR using a number of primers from published sequences, as well as from the TDF sequences, validated the differential gene expression obtained from the cDNA-AFLP display. The third aim was to evaluate selected mutants on station and at different communities. On station field trials were conducted at the ARC-VOPI's research farm under dry land as well as irrigation conditions for the last two seasons. The long term plan is to introgress the drought tolerance trait from the best mutant line into drought susceptible South African cultivars grown by resource-poor farmers. (author)

  11. Evaluation and characterisation of mutant cowpea plants for enhanced abiotic stress tolerance

    International Nuclear Information System (INIS)

    The objective of the project is to use the radiation induced mutations in cowpea to improve cowpea varieties grown by resource-poor farmers in South Africa. The first aim project was to select cowpea plants with improved levels of drought tolerance without alteration to the colour of the testa or the growth form. It was demonstrated that it was possible to examine mutant lines at seedling stage in wooden boxes. Mature plants were screened in rain out shelters and physiological traits for drought stress were identified among the lines tested. Roots of mature plants were also assessed and variation observed could be correlated with drought tolerance. The data demonstrated that physiological methods can be used to screen mutants. The yield performance of some mutant lines proved to be outstanding under well watered, as well as under drought stress conditions. The second aim was to further characterise the most promising mutant lines using molecular and physiologically techniques. cDNA-Amplified Fragment Length Polymorphism showed differential gene expression at different time points of drought stress.The sequenced transcript derived fragments (TDF) showed high homology to expressed sequence tags of soybean, with a possible function in cell defence/resistance and most importantly, signal transduction. Reverse transcription PCR using a number of primers from published sequences, as well as from the TDF sequences, validated the differential gene expression obtained from the cDNA-AFLP display. The third aim was to evaluate selected mutants on station and at different communities. On station field trials were conducted at the ARC-VOPI's research farm under dryland as well as irrigation conditions for the last two seasons. The long term plan is to introgress the drought tolerance trait from the best mutant line into drought susceptible South African cultivars grown by resource-poor farmers. (author)

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

    OpenAIRE

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

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and t...

  13. Volatile isoprenoids as defense compounds during abiotic stress in tropical plants

    Science.gov (United States)

    Jardine, K.

    2015-12-01

    Emissions of volatile isoprenoids from tropical forests play central roles in atmospheric processes by fueling atmospheric chemistry resulting in modified aerosol and cloud lifecycles and their associated feedbacks with the terrestrial biosphere. However, the identities of tropical isoprenoids, their biological and environmental controls, and functions within plants and ecosystems remain highly uncertain. As part of the DOE ARM program's GoAmazon 2014/15 campaign, extensive field and laboratory observations of volatile isoprenoids are being conducted in the central Amazon. Here we report the results of our completed and ongoing activities at the ZF2 forest reserve in the central Amazon. Among the results of the research are the suprisingly high abundance of light-dependent volatile isoprenoid emissions across abundant tree genera in the Amazon in both primary and secondary forests, the discovery of highly reactive monoterpene emissions from Amazon trees, and evidence for the importance of volatile isoprenoids in protecting photosynthesis during oxidative stress under elevated temperatures including energy consumption and direct antioxidant functions and a tight connection betwen volatile isoprenoid emissions, photorespiration, and CO2 recycling within leaves. The results highlight the need to model allocation of carbon to isoprenoids during elevated temperature stress in the tropics.

  14. Nitrogen Assimilation, Abiotic Stress and Glucose 6-Phosphate Dehydrogenase: The Full Circle of Reductants.

    Science.gov (United States)

    Esposito, Sergio

    2016-01-01

    Glucose 6 phosphate dehydrogenase (G6PDH; EC 1.1.1.49) is well-known as the main regulatory enzyme of the oxidative pentose phosphate pathway (OPPP) in living organisms. Namely, in Planta, different G6PDH isoforms may occur, generally localized in cytosol and plastids/chloroplasts. These enzymes are differently regulated by distinct mechanisms, still far from being defined in detail. In the last decades, a pivotal function for plant G6PDHs during the assimilation of nitrogen, providing reductants for enzymes involved in nitrate reduction and ammonium assimilation, has been described. More recently, several studies have suggested a main role of G6PDH to counteract different stress conditions, among these salinity and drought, with the involvement of an ABA depending signal. In the last few years, this recognized vision has been greatly widened, due to studies clearly showing the non-conventional subcellular localization of the different G6PDHs, and the peculiar regulation of the different isoforms. The whole body of these considerations suggests a central question: how do the plant cells distribute the reductants coming from G6PDH and balance their equilibrium? This review explores the present knowledge about these mechanisms, in order to propose a scheme of distribution of reductants produced by G6PDH during nitrogen assimilation and stress. PMID:27187489

  15. In planta transformation of sorghum (Sorghum bicolor (L.) Moench) using TPS1 gene for enhancing tolerance to abiotic stresses

    Indian Academy of Sciences (India)

    Varalaxmi Yellisetty; L. A. Reddy; Maheswari Mandapaka

    2015-09-01

    An in planta transformation protocol for sorghum (Sorghum bicolor (L.) Moench) using shoot apical meristem of germinating seedlings is reported in this study. Agrobacterium tumefaciens strain, LBA4404 with pCAMBIA1303 vector and construct pCAMBIA1303TPS1 were individually used for transformation. Since, the transgene is integrated into the cells of already differentiated tissues, the T0 plants were chimeric and stable integration was observed in T1 generation. -Glucuronidase (GUS) expression in the seedlings and spikelets of emerging cob was the first indication of transformability in T0 generation which was further confirmed by PCR analysis using hpt and TPS1 gene-specific primers. Screening on 25 mg/L hygromycin combined with PCR analysis was used for selection of transformants in the T1 generation. Transformation efficiencies ranged between 34–38% and 26–34% using pCAMBIA1303 vector and construct pCAMBIA1303TPS1, respectively. Molecular characterization of the T2 transgenics using PCR, RT-PCR and Southern blot analyses further revealed the integration, expression and inheritance of the transgene. These results indicate the feasibility of the method to generate transgenics with pCAM-BIA1303 vector and construct pCAMBIA1303TPS1. The abiotic stress tolerance of TPS1 transgenics developed in the present study was evident by the ability of the transformants to tolerate 200 mM NaCl as well as higher root growth and biomass.

  16. Comprehensive Analysis and Expression Profiling of the OsLAX and OsABCB Auxin Transporter Gene Families in Rice (Oryza sativa under Phytohormone Stimuli and Abiotic Stresses

    Directory of Open Access Journals (Sweden)

    Chenglin eChai

    2016-05-01

    Full Text Available The plant hormone auxin regulates many aspects of plant growth and developmental processes. Auxin gradient is formed in plant as a result of polar auxin transportation by three types of auxin transporters such as OsLAX, OsPIN, and OsABCB. We report here the analysis of two rice auxin transporter gene families, OsLAX and OsABCB, using bioinformatics tools, publicly accessible microarray data, and quantitative RT-PCR. There are 5 putative OsLAXs and 22 putative OsABCBs in rice genome, which were mapped on 8 chromosomes. The exon-intron structure of OsLAX genes and properties of deduced proteins were relatively conserved within grass family, while that of OsABCB genes varied greatly. Both constitutive and organ/tissue specific expression patterns were observed in OsLAXs and OsABCBs. Analysis of evolutionarily closely related gene pairs together with organ/tissue specific expression revealed possible function gaining and function losing events during rice evolution. Most OsLAX and OsABCB genes were regulated by drought and salt stress, as well as hormonal stimuli [auxin and Abscisic Acid (ABA], which suggests extensive crosstalk between abiotic stresses and hormone signaling pathways. The existence of large number of auxin and stress related cis-regulatory elements in promoter regions might account for their massive responsiveness of these genes to these environmental stimuli, indicating complexity of regulatory networks involved in various developmental and physiological processes. The comprehensive analysis of OsLAX and OsABCB auxin transporter genes in this study would be helpful for understanding the biological significance of these gene families in hormone signaling and adaptation of rice plants to unfavorable environments.

  17. An S-domain receptor-like kinase, OsSIK2, confers abiotic stress tolerance and delays dark-induced leaf senescence in rice.

    Science.gov (United States)

    Chen, Li-Juan; Wuriyanghan, Hada; Zhang, Yu-Qin; Duan, Kai-Xuan; Chen, Hao-Wei; Li, Qing-Tian; Lu, Xiang; He, Si-Jie; Ma, Biao; Zhang, Wan-Ke; Lin, Qing; Chen, Shou-Yi; Zhang, Jin-Song

    2013-12-01

    Receptor-like kinases play important roles in plant development and defense responses; however, their functions in other processes remain unclear. Here, we report that OsSIK2, an S-domain receptor-like kinase from rice (Oryza sativa), is involved in abiotic stress and the senescence process. OsSIK2 is a plasma membrane-localized protein with kinase activity in the presence of Mn(2+). OsSIK2 is expressed mainly in rice leaf and sheath and can be induced by NaCl, drought, cold, dark, and abscisic acid treatment. Transgenic plants overexpressing OsSIK2 and mutant sik2 exhibit enhanced and reduced tolerance to salt and drought stress, respectively, compared with the controls. Interestingly, a truncated version of OsSIK2 without most of the extracellular region confers higher salt tolerance than the full-length OsSIK2, likely through the activation of different sets of downstream genes. Moreover, seedlings of OsSIK2-overexpressing transgenic plants exhibit early leaf development and a delayed dark-induced senescence phenotype, while mutant sik2 shows the opposite phenotype. The downstream PR-related genes specifically up-regulated by full-length OsSIK2 or the DREB-like genes solely enhanced by truncated OsSIK2 are all induced by salt, drought, and dark treatments. These results indicate that OsSIK2 may integrate stress signals into a developmental program for better adaptive growth under unfavorable conditions. Manipulation of OsSIK2 should facilitate the improvement of production in rice and other crops.

  18. Comprehensive Analysis and Expression Profiling of the OsLAX and OsABCB Auxin Transporter Gene Families in Rice (Oryza sativa) under Phytohormone Stimuli and Abiotic Stresses.

    Science.gov (United States)

    Chai, Chenglin; Subudhi, Prasanta K

    2016-01-01

    The plant hormone auxin regulates many aspects of plant growth and developmental processes. Auxin gradient is formed in plant as a result of polar auxin transportation by three types of auxin transporters such as OsLAX, OsPIN, and OsABCB. We report here the analysis of two rice auxin transporter gene families, OsLAX and OsABCB, using bioinformatics tools, publicly accessible microarray data, and quantitative RT-PCR. There are 5 putative OsLAXs and 22 putative OsABCBs in rice genome, which were mapped on 8 chromosomes. The exon-intron structure of OsLAX genes and properties of deduced proteins were relatively conserved within grass family, while that of OsABCB genes varied greatly. Both constitutive and organ/tissue specific expression patterns were observed in OsLAXs and OsABCBs. Analysis of evolutionarily closely related "gene pairs" together with organ/tissue specific expression revealed possible "function gaining" and "function losing" events during rice evolution. Most OsLAX and OsABCB genes were regulated by drought and salt stress, as well as hormonal stimuli [auxin and Abscisic Acid (ABA)], which suggests extensive crosstalk between abiotic stresses and hormone signaling pathways. The existence of large number of auxin and stress related cis-regulatory elements in promoter regions might account for their massive responsiveness of these genes to these environmental stimuli, indicating complexity of regulatory networks involved in various developmental and physiological processes. The comprehensive analysis of OsLAX and OsABCB auxin transporter genes in this study would be helpful for understanding the biological significance of these gene families in hormone signaling and adaptation of rice plants to unfavorable environments. PMID:27200061

  19. 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.

  20. Contribution of genetic diversity for improvement of some abiotic stresses in wheat (abstract)

    International Nuclear Information System (INIS)

    Wheat improvement has predominantly been accomplished through conventional plant breeding methodologies. This approach shall continue to be the predominant procedure in the future. Genetic diversity is crucial for crop improvement and in the Triticeae family it resides in the primary, secondary and tertiary gene pools. These gene pools can be utilize for wheat improvement by producing genetic stocks where the alien gene pools can be combined with durum and bread wheat cultivars via interspecific and intergeneric hybridization. Adopting the interspecific route strategies has led to the production of several genetic stocks, which are elucidated here. The categories include the amphiploids of the A, B, and D genomes with durum cultivars (AAAABB, AABBBB, AABBDD) and new AADD tetraploids. Tertiary gene pool species (more complex to utilize) are a potent resource for gene pyramiding, which contribute towards stress durability and addresses sustainable agricultural aspects. The conventional classical protocols of introgressing alien genetic diversity into wheat are complex, and long-term in generating farmer usable products. The gene transfer procedures are further complicated when the stress trait has multigenic control associated with several alien chromosomes. Our current approach has incorporated a novel strategy for promoting alien chromosome introgression involving wheat/alien homeologous as well as non-homeologous chromosomes. The protocol comprises of hybridizing the Phph based amphiploid with the phph Chinese Spring wheat genetic stock to yield heterozygote Phph derivatives. From selfing of the heterozygotes or from their derived haploids via wheat/maize crosses the ph derivatives are identified by a PCR diagnostic. The ph seedlings form the reservoir of wheat/alien chromosome translocations which are identified by Giemsa C-banding / fluorescent in situ hybridization (FISH). Plants with translocations are step-wise advanced by backcrosses to elite wheat cultivars

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

    OpenAIRE

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

    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 ...

  2. Osmotic stress represses strigolactone biosynthesis in Lotus japonicus roots: exploring the interaction between strigolactones and ABA under abiotic stress

    NARCIS (Netherlands)

    Liu, J.; He, H.; Vitali, M.; Visentin, I.; Charnikhova, T.; Haider, I.; Schubert, A.; Ruyter-Spira, C.P.

    2015-01-01

    Main conclusion Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress. Abstract Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators

  3. Changes of plant cell wall components under abiotic stresses:A review%非生物胁迫下植物细胞壁组分变化

    Institute of Scientific and Technical Information of China (English)

    裴惠娟; 张满效; 安黎哲

    2011-01-01

    植物细胞壁主要由纤维素、半纤维素、果胶、木质素和糖蛋白组成,其在植物生长中主要起结构支持、物质运输和抵御逆境的作用.植物生长在受到各种环境信号影响后,细胞壁特性会发生很大改变.这些环境信号也会改变细胞壁组分的含量和结构,从而改变细胞壁机械特性.这种细胞壁的改变可以认为是植物对环境胁迫的响应.本文主要综述在非生物环境胁迫下,包括水分亏缺、低温胁迫、重金属胁迫和增强UV-B辐射下细胞壁多糖含量和结构,细胞壁结构蛋白和细胞壁相关酶活性,以及分布在细胞间隙的小分子物质的响应和机制,结合近年来细胞壁相关基因水平、基因组水平和蛋白组水平方面的研究结果,讨论了今后该领域的研究方向.%Plant cell wall mainly consists of cellulose , hemi-cellulose , pectic substances, lignin , and proteins. It has a number of functions, including maintain cell stability, transport materials, and protect cell against environmental stresses. When the plant life cycle is affected by various environmental signals, cell wall properties will have great change, and cell wall components content and structure will be also changed, which is supposed to be the causes of the changes in cell wall mechanical properties. These changes can be considered as the responses of plants to environmental stress. This paper summarized the research advances in the changes of cell wall polysaccharides and proteins content and structure and related enzyme activities, and the responses and relevant mechanisms of small molecules secreted to cell spaces under abiotic environmental stresses, such as water deficit, low temperature stress, heavy metals stress, and UV-B radiation. In considering of the recent researches at gene, genomic, and proteomics levels, the future research directions in this area were also discussed.

  4. 银杏 GbSAD 基因对非生物胁迫的响应及原核表达1)%Expression Analysis of GbSAD from Ginkgo biloba in Response to Abiotic Stress and Its Prokaryotic Expression

    Institute of Scientific and Technical Information of China (English)

    刘新亮; 蔡金峰; 王欢利; 曹福亮

    2015-01-01

    以悬浮培养的银杏愈伤组织为材料,采用荧光定量RT-PCR研究了GbSAD基因在高盐和不同外源激素处理条件下的表达模式。结果表明:外施100μmol· L-1水杨酸(SA)后,GbSAD表达量发生显著变化;外施100μmol· L-1脱落酸(ABA)、40μmol· L-1乙烯利(ETH)、100μmol· L-1茉莉酸甲酯(MeJA),GbSAD表达量未呈现显著变化;外施200 mmol· L-1氯化钠( NaCl),GbSAD表达量小幅度降低。 GbSAD组织表达分析表明基因在根、茎、叶、雄花和雌花中均有表达,在叶中表达量最高。 SAD氨基酸序列同源比对发现,GbSAD与其他被子植物的序列相似度较高,表明GbSAD在进化上较保守。将银杏GbSAD克隆到原核表达载体pET-32a(+)中,转化大肠杆菌(Escherichia coli) BL21(DE3)并诱导表达。结果表明,GbSAD蛋白在1 mmol· L-1IPTG的诱导下,培养2 h即能实现融合蛋白的高效表达,为进一步纯化目的蛋白及研究其功能奠定了基础。%We studied the expression pattern of GbSAD under abiotic stress , and cultured the callus of ginkgo in the MS liquid media supplied with NaCl and different exogenous hormones .The expression of GbSAD was induced by exogenous SA ( 100μmol· L-1), but not altered when exposed to exogenous ABA (100μmol· L-1), ETH (40μmol· L-1) or MeJA (100μmol· L-1 ) .The expression of GbSAD was slightly down-regulated by NaCl treatment .GbSAD expressed in various tis-sues, and had the highest expression level in leaves .The deduced amino acid sequence of GbSAD shared a higher identity with SAD from other angiosperms , which indicated that GbSAD was remarkably conservative throughout evolution .We cloned GbSAD into prokaryotic expression vector pET-32a(+) , and then transformed the recombined plasmid into Esche-richia coliBL21 ( DE3) to induce its expression .The fusion protein was expressed to a high level at 1 mmol· L-1 IPTG in-duction for 2 h

  5. Boechera species exhibit species-specific responses to combined heat and high light stress.

    Science.gov (United States)

    Gallas, Genna; Waters, Elizabeth R

    2015-01-01

    As sessile organisms, plants must be able to complete their life cycle in place and therefore tolerance to abiotic stress has had a major role in shaping biogeographical patterns. However, much of what we know about plant tolerance to abiotic stresses is based on studies of just a few plant species, most notably the model species Arabidopsis thaliana. In this study we examine natural variation in the stress responses of five diverse Boechera (Brassicaceae) species. Boechera plants were exposed to basal and acquired combined heat and high light stress. Plant response to these stresses was evaluated based on chlorophyll fluorescence measurements, induction of leaf chlorosis, and gene expression. Many of the Boechera species were more tolerant to heat and high light stress than A. thaliana. Gene expression data indicates that two important marker genes for stress responses: APX2 (Ascorbate peroxidase 2) and HsfA2 (Heat shock transcription factor A2) have distinct species-specific expression patterns. The findings of species-specific responses and tolerance to stress indicate that stress pathways are evolutionarily labile even among closely related species.

  6. An Expressed Sequence Tag Analysis of the Intertidal Brown Seaweeds Fucus serratus (L.) and F. vesiculosus (L.) (Heterokontophyta, Phaeophyceae) in Response to Abiotic Stressors

    NARCIS (Netherlands)

    Pearson, Gareth A.; Hoarau, Galice; Lago-Leston, Asuncion; Coyer, James A.; Kube, Michael; Reinhardt, Richard; Henckel, Kolja; Serrao, Ester T. A.; Corre, Erwan; Olsen, Jeanine L.

    2010-01-01

    In order to aid gene discovery and uncover genes responding to abiotic stressors in stress-tolerant brown algae of the genus Fucus, expressed sequence tags (ESTs) were studied in two species, Fucus serratus and Fucus vesiculosus. Clustering of over 12,000 ESTs from three libraries for heat shock/rec

  7. Stress response signaling and virulence: insights from entomopathogenic fungi.

    Science.gov (United States)

    Ortiz-Urquiza, Almudena; Keyhani, Nemat O

    2015-08-01

    The Ascomycete fungal insect pathogens, Beauveria and Metarhizium spp. have emerged as model systems with which to probe diverse aspects of fungal growth, stress response, and pathogenesis. Due to the availability of genomic resources and the development of robust methods for genetic manipulation, the last 5 years have witnessed a rapid increase in the molecular characterization of genes and their pathways involved in stress response and signal transduction in these fungi. These studies have been performed mainly via characterization of gene deletion/knockout mutants and have included the targeting of general proteins involved in stress response and/or virulence, e.g. catalases, superoxide dismutases, and osmolyte balance maintenance enzymes, membrane proteins and signaling pathways including GPI anchored proteins and G-protein coupled membrane receptors, MAPK pathways, e.g. (i) the pheromone/nutrient sensing, Fus3/Kss1, (ii) the cell wall integrity, Mpk1, and (iii) the high osmolarity, Hog1, the PKA/adenyl cyclase pathway, and various downstream transcription factors, e.g. Msn2, CreA and Pac1. Here, we will discuss current research that strongly suggests extensive underlying contributions of these biochemical and signaling pathways to both abiotic stress response and virulence. PMID:25113413

  8. Genome-wide analysis and expression patterns of ZF-HD transcription factors under different developmental tissues and abiotic stresses in Chinese cabbage.

    Science.gov (United States)

    Wang, Wenli; Wu, Peng; Li, Ying; Hou, XiLin

    2016-06-01

    The ZF-HD gene family plays an important role in plant developmental processes and stress responses. However, the function of the ZF-HD genes in Chinese cabbage remains largely unknown. Chinese cabbage (Brassica rapa ssp. pekinensis) is a member of one of the most important leaf vegetables grown worldwide. The entire Chinese cabbage genome sequence has been determined, and more than forty thousand proteins have been identified to date. In this study, 31 ZF-HD genes were identified in Chinese cabbage. We show here that the BraZF-HD genes could be categorized into ZHD and MIF subfamilies. Among them, ZHD genes are plant-specific, nearly all intronless, and related to MINI ZINC FINGER genes that possess only the zinc finger. Phylogenetic analysis suggested that ZHDs have expanded considerably during angiosperm evolution. In addition, the ZHD group has 24 members, which is twice as much as the Arabidopsis ZHD group, indicating that the Chinese cabbage ZHD genes have been retained more frequently than other group genes. Real-time PCR analysis showed that most of BraZF-HD genes are preferentially expressed in flower. Furthermore, most of these genes are significantly induced under photoperiod or vernalization conditions, as well as abiotic stresses. Thereby implying that they may play important roles in these processes. This study provides insight into the evolution of ZF-HD genes in Chinese cabbage genome and may aid efforts to further characterize the function of these predicted ZF-HD genes in flowering and resistance. PMID:26546019

  9. P5CDH affects the pathways contributing to Pro synthesis after ProDH activation by biotic and abiotic stress conditions

    Directory of Open Access Journals (Sweden)

    Yanina Soledad Rizzi

    2015-07-01

    Full Text Available Plants facing adverse conditions usually alter proline (Pro metabolism, generating changes that help restore the cellular homeostasis. These organisms synthesize Pro from glutamate (Glu or ornithine (Orn by two-step reactions that share Δ1 pyrroline-5-carboxylate (P5C as intermediate. In the catabolic process, Pro is converted back to Glu using a different pathway that involves Pro dehydrogenase (ProDH, P5C dehydrogenase (P5CDH, and P5C as intermediate. Little is known about the coordination of the catabolic and biosynthetic routes under stress. To address this issue, we analyzed how P5CDH affects the activation of Pro synthesis, in Arabidopsis tissues that increase ProDH activity by transient exposure to exogenous Pro, or infection with Pseudomonas syringae pv. tomato. Wild type (Col-0 and p5cdh mutant plants subjected to these treatments were used to monitor the Pro, Glu and Orn levels, as well as the expression of genes from Pro metabolism. Col-0 and p5cdh tissues consecutively activated ProDH and Pro biosynthetic genes under both conditions. However, they manifested a different coordination between these routes. When external Pro supply was interrupted, wild type leaves degraded Pro to basal levels at which point Pro synthesis, mainly via Glu, became activated. Under the same condition, p5cdh leaves sustained ProDH induction without reducing the Pro content but rather increasing it, apparently by stimulating the Orn pathway. In response to pathogen infection, both genotypes showed similar trends. While Col-0 plants seemed to induce both Pro biosynthetic routes, p5cdh mutant plants may primarily activate the Orn route. Our study contributes to the functional characterization of P5CDH in biotic and abiotic stress conditions, by revealing its capacity to modulate the fate of P5C, and prevalence of Orn or Glu as Pro precursors in tissues that initially consumed Pro.

  10. A step towards understanding plant responses to multiple environmental stresses: a genome-wide study.

    Science.gov (United States)

    Sewelam, Nasser; Oshima, Yoshimi; Mitsuda, Nobutaka; Ohme-Takagi, Masaru

    2014-09-01

    In natural habitats, especially in arid areas, plants are often simultaneously exposed to multiple abiotic stresses, such as salt, osmotic and heat stresses. However, most analyses of gene expression in stress responses examine individual stresses. In this report, we compare gene expression in individual and combined stresses. We show that combined stress treatments with salt, mannitol and heat induce a unique pattern of gene expression that is not a simple merge of the individual stress responses. Under multiple stress conditions, expression of most heat and salt stress-responsive genes increased to levels similar to or higher than those measured in single stress conditions, but osmotic stress-responsive genes increased to lower levels. Genes up-regulated to higher levels under multiple stress condition than single stress conditions include genes for heat shock proteins, heat shock regulators and late embryogenesis abundant proteins (LEAs), which protect other proteins from damage caused by stresses, suggesting their importance in multiple stress condition. Based on this analysis, we identify candidate genes for engineering crop plants tolerant to multiple stresses. PMID:24417440

  11. Comprehensive analysis of SET domain gene family in foxtail millet identifies the putative role of SiSET14 in abiotic stress tolerance

    Science.gov (United States)

    Yadav, Chandra Bhan; Muthamilarasan, Mehanathan; Dangi, Anand; Shweta, Shweta; Prasad, Manoj

    2016-01-01

    SET domain-containing genes catalyse histone lysine methylation, which alters chromatin structure and regulates the transcription of genes that are involved in various developmental and physiological processes. The present study identified 53 SET domain-containing genes in C4 panicoid model, foxtail millet (Setaria italica) and the genes were physically mapped onto nine chromosomes. Phylogenetic and structural analyses classified SiSET proteins into five classes (I–V). RNA-seq derived expression profiling showed