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Sample records for distancia entre plantas

  1. PREJUICIO Y DISTANCIA SOCIAL HACIA PERSONAS HOMOSEXUALES POR PARTE DE JÓVENES UNIVERSITARIOS

    PubMed Central

    Fernández Rodríguez, María del C.; Squiabro, José Calderón

    2014-01-01

    Se realizó un estudio descriptivo transversal con el propósito de explorar actitudes de rechazo y distancia social hacia las personas gays y lesbianas (GL) en 565 universitarios. Se utilizó una escala para medir Prejuicio y otra escala para medir Distancia Social. Los participantes reflejaron niveles moderados de prejuicio y distancia social (DS) hacia las personas gays y lesbianas. Los varones (M=104.5, DT= 27.47) mostraron significativamente más prejuicio que las mujeres (M=98.8, DT= 23.41). Los hombres (M=22.7, DT= 7.00) mostraron significativamente mayor DS que las mujeres (M=21.1, DT= 5.41). Las personas que asisten con regularidad a la iglesia mostraron más prejuicio y DS que los que no asisten. Se analiza importancia de incluir el tema de la diversidad sexual a través del currículo para desmontar prejuicios hacia la comunidad homosexual. PMID:25606066

  2. Exploring Strategies of Assessment and Results in the Spanish Universidad Nacional de Educacion a Distancia and the United Kingdom Open University.

    ERIC Educational Resources Information Center

    James, Arthur

    The strategies of student evaluation and the patterns of results are compared for The Universidad Nacional de Educacion a Distancia (UNED) in Spain and The Open University of The United Kingdom. Both universities operate a system of undergraduate subject credits leading to a degree, but the length of the courses of the two systems differ. UNED…

  3. Comparisons in the Organisation, Methods, and Results of the Universidad Nacional de Educacion a Distancia (Spain) and The Open University of The United Kingdom.

    ERIC Educational Resources Information Center

    James, Arthur

    The organization, methods, and outcomes of the distance education systems at the Universidad Nacional de Educacion a Distancia (UNED) in Spain and The Open University of the United Kingdom are compared. The following topics are covered: higher education in Spain, UNED's ideology, student characteristics in both universities, organization,…

  4. Non-random sharing of Plantae genes.

    PubMed

    Chan, Cheong Xin; Bhattacharya, Debashish

    2011-05-01

    The power of eukaryote genomics relies strongly on taxon sampling. This point was underlined in a recent analysis of red algal genome evolution in which we tested the Plantae hypothesis that posits the monophyly of red, green (including plants) and glaucophyte algae. The inclusion of novel genome data from two mesophilic red algae enabled us to robustly demonstrate the sisterhood of red and green algae in the tree of life. Perhaps more exciting was the finding that >1,800 putative genes in the unicellular red alga Porphyridium cruentum showed evidence of gene-sharing with diverse lineages of eukaryotes and prokaryotes. Here we assessed the correlation between the putative functions of these shared genes and their susceptibility to transfer. It turns out that genes involved in complex interactive networks such as biological regulation and transcription/translation are less susceptible to endosymbiotic or horizontal gene transfer, when compared to genes with metabolic and transporter functions. PMID:21980581

  5. "Entre libre" dans la classe ("Entre Libre" in the Classroom).

    ERIC Educational Resources Information Center

    Compte, Carmen

    1987-01-01

    In an interview, two teachers describe and discuss their different classroom use of the same set of instructional materials for "Entre Libre" and compare the results. Activities include role playing, music, and reporting. (MSE)

  6. Accidentes en plantas nucleares de electricidad y el riesgo de cáncer

    Cancer.gov

    Hoja informativa acerca de los riesgos del cáncer asociados con accidentes en plantas nucleares de electricidad. Incluye información para pacientes con cáncer que viven en una zona que puede haber sido afectada por un accidente en una planta nuclear.

  7. Plantas crucíferas y la prevención del cáncer

    Cancer.gov

    Hoja informativa que resume los resultados de estudios sobre las plantas crucíferas y el cáncer. Incluye una lista de plantas crucíferas y las guías alimentarias recomendadas para el consumo de verduras.

  8. Time Gating of Chloroplast Autofluorescence Allows Clearer Fluorescence Imaging In Planta

    PubMed Central

    Kodama, Yutaka

    2016-01-01

    Chloroplast, an organelle facilitating photosynthesis, exhibits strong autofluorescence, which is an undesired background signal that restricts imaging experiments with exogenous fluorophore in plants. In this study, the autofluorescence was characterized in planta under confocal laser microscopy, and it was found that the time-gated imaging technique completely eliminates the autofluorescence. As a demonstration of the technique, a clearer signal of fluorescent protein-tagged phototropin, a blue-light photoreceptor localized at the chloroplast periphery, was visualized in planta. PMID:27027881

  9. Time Gating of Chloroplast Autofluorescence Allows Clearer Fluorescence Imaging In Planta.

    PubMed

    Kodama, Yutaka

    2016-01-01

    Chloroplast, an organelle facilitating photosynthesis, exhibits strong autofluorescence, which is an undesired background signal that restricts imaging experiments with exogenous fluorophore in plants. In this study, the autofluorescence was characterized in planta under confocal laser microscopy, and it was found that the time-gated imaging technique completely eliminates the autofluorescence. As a demonstration of the technique, a clearer signal of fluorescent protein-tagged phototropin, a blue-light photoreceptor localized at the chloroplast periphery, was visualized in planta. PMID:27027881

  10. Physiology of ex planta nitrogenase activity in Rhizobium japonicum

    SciTech Connect

    Agarwal, A.K.; Keister, D.L.

    1983-05-01

    Thirty-nine wild-type strains of Rhizobium japonicum have been studied for their ability to synthesize nitrogenase ex planta in defined liquid media under microaerobic conditions. Twenty-one produced more than trace amounts of acetylene reduction activity, but only a few of these yielded high activity. The oxygen response curves were similar for most of the nitrogenase-positive strains. The strains derepressible for activity had several phenotypic characteristics different from non-derepressible strains. These included slower growth and lower oxygen consumption under microaerobic conditions and lower extracellular polysaccharide production. Extracellular polysaccharide production during growth on gluconate in every nitrogenase-positive strain assayed was lower under both aerobic and microaerobic conditions than the non-depressible strains. These phenotypic characteristics may be representative of a genotype of a subspecies of R. japonicum. These studies were done in part to enlarge the base number of strains available for studies on the physiology, biochemistry, and genetics of nitrogen fixation. (35 Refs.)

  11. In vitro and in planta compatibility of insecticides and the endophytic entomopathogen, Lecanicillium lecanii.

    PubMed

    Gurulingappa, Pampapathy; Mc Gee, Peter; Sword, Gregory A

    2011-08-01

    In an attempt to clarify the potential role of endophytic fungi in integrated pest management, the compatibility of an endophytic isolate of Lecanicillium lecanii (Zimmermann) Gams & Zare (Hyphomycetes) with nine insecticides used against Aphis gossypii Glover (Homoptera : Aphididae) was examined both in vitro over 14 days and in planta. In the laboratory, most insecticides partially or completely inhibited the germination of conidia and growth of hyphae in nutrient-rich conditions. Endosulfan completely inhibited the germination of conidia and hyphal growth. In contrast, all insecticides were compatible with L. lecanii in planta, and the fungus was readily recovered from inoculated, colonized leaves. These data support the hypothesis that endophytic L. lecanii will be unaffected by insecticides and could be integrated in the management of pests in cotton. PMID:21424605

  12. In planta mutagenesis determines the functional regions of the wheat puroindoline proteins.

    PubMed

    Feiz, L; Beecher, B S; Martin, J M; Giroux, M J

    2009-11-01

    In planta analysis of protein function in a crop plant could lead to improvements in understanding protein structure/function relationships as well as selective agronomic or end product quality improvements. The requirements for successful in planta analysis are a high mutation rate, an efficient screening method, and a trait with high heritability. Two ideal targets for functional analysis are the Puroindoline a and Puroindoline b (Pina and Pinb, respectively) genes, which together compose the wheat (Triticum aestivum L.) Ha locus that controls grain texture and many wheat end-use properties. Puroindolines (PINs) together impart soft texture, and mutations in either PIN result in hard seed texture. Studies of the PINs' mode of action are limited by low allelic variation. To create new Pin alleles and identify critical function-determining regions, Pin point mutations were created in planta via EMS treatment of a soft wheat. Grain hardness of 46 unique PIN missense alleles was then measured using segregating F(2):F(3) populations. The impact of individual missense alleles upon PIN function, as measured by grain hardness, ranged from neutral (74%) to intermediate to function abolishing. The percentage of function-abolishing mutations among mutations occurring in both PINA and PINB was higher for PINB, indicating that PINB is more critical to overall Ha function. This is contrary to expectations in that PINB is not as well conserved as PINA. All function-abolishing mutations resulted from structure-disrupting mutations or from missense mutations occurring near the Tryptophan-rich region. This study demonstrates the feasibility of in planta functional analysis of wheat proteins and that the Tryptophan-rich region is the most important region of both PINA and PINB. PMID:19752217

  13. Screening for in planta protein-protein interactions combining bimolecular fluorescence complementation with flow cytometry

    PubMed Central

    2012-01-01

    Understanding protein and gene function requires identifying interaction partners using biochemical, molecular or genetic tools. In plants, searching for novel protein-protein interactions is limited to protein purification assays, heterologous in vivo systems such as the yeast-two-hybrid or mutant screens. Ideally one would be able to search for novel protein partners in living plant cells. We demonstrate that it is possible to screen for novel protein-protein interactions from a random library in protoplasted Arabidopsis plant cells and recover some of the interacting partners. Our screen is based on capturing the bi-molecular complementation of mYFP between an YN-bait fusion partner and a completely random prey YC-cDNA library with FACS. The candidate interactions were confirmed using in planta BiFC assays and in planta FRET-FLIM assays. From this work, we show that the well characterized protein Calcium Dependent Protein Kinase 3 (CPK3) interacts with APX3, HMGB5, ORP2A and a ricin B-related lectin domain containing protein At2g39050. This is one of the first randomin planta screens to be successfully employed. PMID:22789293

  14. In planta anthocyanin degradation by a vacuolar class III peroxidase in Brunfelsia calycina flowers.

    PubMed

    Zipor, Gadi; Duarte, Patrícia; Carqueijeiro, Inês; Shahar, Liat; Ovadia, Rinat; Teper-Bamnolker, Paula; Eshel, Dani; Levin, Yishai; Doron-Faigenboim, Adi; Sottomayor, Mariana; Oren-Shamir, Michal

    2015-01-01

    In contrast to detailed knowledge regarding the biosynthesis of anthocyanins, the largest group of plant pigments, little is known about their in planta degradation. It has been suggested that anthocyanin degradation is enzymatically controlled and induced when beneficial to the plant. Here we investigated the enzymatic process in Brunfelsia calycina flowers, as they changed color from purple to white. We characterized the enzymatic process by which B. calycina protein extracts degrade anthocyanins. A candidate peroxidase was partially purified and characterized and its intracellular localization was determined. The transcript sequence of this peroxidase was fully identified. A basic peroxidase, BcPrx01, is responsible for the in planta degradation of anthocyanins in B. calycina flowers. BcPrx01 has the ability to degrade complex anthocyanins, it co-localizes with these pigments in the vacuoles of petals, and both the mRNA and protein levels of BcPrx01 are greatly induced parallel to the degradation of anthocyanins. Both isoelectric focusing (IEF) gel analysis and 3D structure prediction indicated that BcPrx01 is cationic. Identification of BcPrx01 is a significant breakthrough both in the understanding of anthocyanin catabolism in plants and in the field of peroxidases, where such a consistent relationship between expression levels, in planta subcellular localization and activity has seldom been demonstrated. PMID:25256351

  15. Time-weighted average SPME analysis for in planta determination of cVOCs.

    PubMed

    Sheehan, Emily M; Limmer, Matt A; Mayer, Philipp; Karlson, Ulrich Gosewinkel; Burken, Joel G

    2012-03-20

    The potential of phytoscreening for plume delineation at contaminated sites has promoted interest in innovative, sensitive contaminant sampling techniques. Solid-phase microextraction (SPME) methods have been developed, offering quick, undemanding, noninvasive sampling without the use of solvents. In this study, time-weighted average SPME (TWA-SPME) sampling was evaluated for in planta quantification of chlorinated solvents. TWA-SPME was found to have increased sensitivity over headspace and equilibrium SPME sampling. Using a variety of chlorinated solvents and a polydimethylsiloxane/carboxen (PDMS/CAR) SPME fiber, most compounds exhibited near linear or linear uptake over the sampling period. Smaller, less hydrophobic compounds exhibited more nonlinearity than larger, more hydrophobic molecules. Using a specifically designed in planta sampler, field sampling was conducted at a site contaminated with chlorinated solvents. Sampling with TWA-SPME produced instrument responses ranging from 5 to over 200 times higher than headspace tree core sampling. This work demonstrates that TWA-SPME can be used for in planta detection of a broad range of chlorinated solvents and methods can likely be applied to other volatile and semivolatile organic compounds. PMID:22332592

  16. i Planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This application was designed for farmers, agriculture researchers, and gardeners. The application includes a calculator, a data logger, and a GPS mapping function. It was designed for vegetable farming but can be used for open field applications. The calculator solves for the amount of pesticide,...

  17. A method for obtaining RNA from Hemileia vastatrix appressoria produced in planta, suitable for transcriptomic analyses.

    PubMed

    Loureiro, Andreia; Gil Azinheira, Helena; do Céu Silva, Maria; Talhinhas, Pedro

    2015-11-01

    Appressoria are the first infection structures developed by rust fungi and require specific topographic signals from the host for their differentiation. The ease in obtaining appressoria in vitro for these biotrophic fungi led to studies concerning gene expression and gene discovery at appressorial level, avoiding the need to distinguish plant and fungal transcripts. However, in some pathosystems, it was observed that gene expression in appressoria seems to be influenced by host-derived signals, suggesting that transcriptomic analyses performed from in planta differentiated appressoria would be potentially more informative than those from in vitro differentiated appressoria. Nevertheless analysing appressorial RNA obtained from in planta samples is often hampered by an excessive dilution of fungal RNA within plant RNA, besides uncertainty regarding the fungal or plant origin of RNA from highly conserved genes. To circumvent these difficulties, we have recovered Hemileia vastatrix appressoria from Arabica coffee leaf surface using a film of nitrocellulose dissolved in butyl and ethyl acetates (nail polish), and extracted fungal RNA from the polish peel. RNA thus obtained is of good quality and usable for cDNA synthesis and transcriptomic (quantitative PCR) studies. This method could provide the means to investigate specific host-induced appressoria-related fungal pathogenicity factors. PMID:26466882

  18. Dynamic root exudation of sorgoleone and its in planta mechanism of action

    PubMed Central

    Dayan, Franck E.; Howell, J'Lynn; Weidenhamer, Jeffrey D.

    2009-01-01

    The oily droplets exuded from the root hairs of sorghum are composed of a 1:1 ratio of sorgoleone and its lipid resorcinol analogue. The production of these droplets appears to be suppressed when c. 20 μg of exudate mg−1 root dry weight accumulates at the tip of the root hairs. However, more exudate is produced following gentle washing of the roots with water, suggesting that the biosynthesis of lipid benzoquinones and resorcinols is a dynamic process. Sorgoleone interferes with several molecular target sites, including photosynthetic electron transport, in in vitro assays. However, the in planta mechanism of action of sorgoleone remains controversial because it is not clear whether this lipid benzoquinone exuding from the roots of sorghum is taken up by roots of the receiving plants and translocated to their foliage where it must enter the chloroplast and inhibit PSII in the thylakoid membrane. Experiments designed to test the in planta mode of action of sorgoleone demonstrated that it has no effect on the photosynthesis of older plants, but inhibits photosynthesis in germinating seedlings. Sorgoleone is not translocated acropetally in older plants, but can be absorbed through the hypocotyl and cotyledonary tissues. Therefore, the mode of action of sorgoleone may be the result of inhibition of photosynthesis in young seedlings in concert with inhibition of its other molecular target sites in older plants. PMID:19357432

  19. Bcmimp1, a Botrytis cinerea Gene Transiently Expressed in planta, Encodes a Mitochondrial Protein

    PubMed Central

    Benito-Pescador, David; Santander, Daniela; Arranz, M.; Díaz-Mínguez, José M.; Eslava, Arturo P.; van Kan, Jan A. L.; Benito, Ernesto P.

    2016-01-01

    Botrytis cinerea is a widespread necrotrophic fungus which infects more than 200 plant species. In an attempt to characterize the physiological status of the fungus in planta and to identify genetic factors contributing to its ability to infect the host cells, a differential gene expression analysis during the interaction B. cinerea-tomato was carried out. Gene Bcmimp1 codes for a mRNA detected by differential display in the course of this analysis. During the interaction with the host, it shows a transient expression pattern with maximal expression levels during the colonization and maceration of the infected tissues. Bioinformatic analysis suggested that BCMIMP1 is an integral membrane protein located in the mitochondrial inner membrane. Co-localization experiments with a BCMIMP1-GFP fusion protein confirmed that the protein is targeted to the mitochondria. ΔBcmimp1 mutants do not show obvious phenotypic differences during saprophytic growth and their infection ability was unaltered as compared to the wild-type. Interestingly, the mutants produced increased levels of reactive oxygen species, likely as a consequence of disturbed mitochondrial function. Although Bcmimp1 expression is enhanced in planta it cannot be considered a pathogenicity factor. PMID:26952144

  20. Comparative analysis of the in vitro and in planta secretomes from Mycosphaerella fijiensis isolates.

    PubMed

    Escobar-Tovar, Lina; Guzmán-Quesada, Mauricio; Sandoval-Fernández, Jorge A; Gómez-Lim, Miguel A

    2015-06-01

    Black Sigatoka, a devastating disease of bananas and plantains worldwide, is caused by the fungus Mycosphaerella fijiensis. Several banana cultivars such as 'Yangambi Km 5' and Calcutta IV, have been known to be resistant to the fungus, but the resistance has been broken in 'Yangambi Km 5' in Costa Rica. Since the resistance of this variety still persists in Mexico, the aim of this study was to compare the in vitro and in planta secretomes from two avirulent and virulent M. fijiensis isolates using proteomics and bioinformatics approaches. We aimed to identify differentially expressed proteins in fungal isolates that differ in pathogenicity and that might be responsible for breaking the resistance in 'Yangambi Km 5'. We were able to identify 90 protein spots in the secretomes of fungal isolates encoding 42 unique proteins and 35 differential spots between them. Proteins involved in carbohydrate transport and metabolism were more prevalent. Several proteases, pathogenicity-related, ROS detoxification and unknown proteins were also highly or specifically expressed by the virulent isolate in vitro or during in planta infection. An unknown protein representing a virulence factor candidate was also identified. These results demonstrated that the secretome reflects major differences between both M. fijiensis isolates. PMID:25986542

  1. Simultaneous specific in planta visualization of root-colonizing fungi using fluorescence in situ hybridization (FISH).

    PubMed

    Vági, Pál; Knapp, Dániel G; Kósa, Annamária; Seress, Diána; Horváth, Áron N; Kovács, Gábor M

    2014-05-01

    In planta detection of mutualistic, endophytic, and pathogenic fungi commonly colonizing roots and other plant organs is not a routine task. We aimed to use fluorescence in situ hybridization (FISH) for simultaneous specific detection of different fungi colonizing the same tissue. We have adapted ribosomal RNA (rRNA) FISH for visualization of common mycorrhizal (arbuscular- and ectomycorrhiza) and endophytic fungi within roots of different plant species. Beside general probes, we designed and used specific ones hybridizing to the large subunit of rRNA with fluorescent dyes chosen to avoid or reduce the interference with the autofluorescence of plant tissues. We report here an optimized efficient protocol of rRNA FISH and the use of both epifluorescence and confocal laser scanning microscopy for simultaneous specific differential detection of those fungi colonizing the same root. The method could be applied for the characterization of other plant-fungal interactions, too. In planta FISH with specific probes labeled with appropriate fluorescent dyes could be used not only in basic research but to detect plant colonizing pathogenic fungi in their latent life-period. PMID:24221902

  2. In-planta Sporulation Capacity Enhances Infectivity and Rhizospheric Competitiveness of Frankia Strains.

    PubMed

    Cotin-Galvan, Laetitia; Pozzi, Adrien C; Schwob, Guillaume; Fournier, Pascale; Fernandez, Maria P; Herrera-Belaroussi, Aude

    2016-01-01

    Frankia Sp+ strains maintain their ability to sporulate in symbiosis with actinorhizal plants, producing abundant sporangia inside host plant cells, in contrast to Sp- strains, which are unable to perform in-planta sporulation. We herein examined the role of in-planta sporulation in Frankia infectivity and competitiveness for root infection. Fifteen strains belonging to different Sp+ and Sp- phylogenetic lineages were inoculated on seedlings of Alnus glutinosa (Ag) and A. incana (Ai). Strain competitiveness was investigated by performing Sp-/Sp+ co-inoculations. Plant inoculations were standardized using crushed nodules obtained under laboratory-controlled conditions (same plant species, age, and environmental factors). Specific oligonucleotide primers were developed to identify Frankia Sp+ and/or Sp- strains in the resulting nodules. Single inoculation experiments showed that (i) infectivity by Sp+ strains was significantly greater than that by Sp- strains, (ii) genetically divergent Sp+ strains exhibited different infective abilities, and (iii) Sp+ and Sp- strains showed different host preferences according to the origin (host species) of the inocula. Co-inoculations of Sp+ and Sp- strains revealed the greater competitiveness of Sp+ strains (98.3 to 100% of Sp+ nodules, with up to 15.6% nodules containing both Sp+ and Sp- strains). The results of the present study highlight differences in Sp+/Sp- strain ecological behaviors and provide new insights to strengthen the obligate symbiont hypothesis for Sp+ strains. PMID:26726131

  3. In-planta Sporulation Capacity Enhances Infectivity and Rhizospheric Competitiveness of Frankia Strains

    PubMed Central

    Cotin-Galvan, Laetitia; Pozzi, Adrien C.; Schwob, Guillaume; Fournier, Pascale; Fernandez, Maria P.; Herrera-Belaroussi, Aude

    2016-01-01

    Frankia Sp+ strains maintain their ability to sporulate in symbiosis with actinorhizal plants, producing abundant sporangia inside host plant cells, in contrast to Sp− strains, which are unable to perform in-planta sporulation. We herein examined the role of in-planta sporulation in Frankia infectivity and competitiveness for root infection. Fifteen strains belonging to different Sp+ and Sp− phylogenetic lineages were inoculated on seedlings of Alnus glutinosa (Ag) and A. incana (Ai). Strain competitiveness was investigated by performing Sp−/Sp+ co-inoculations. Plant inoculations were standardized using crushed nodules obtained under laboratory-controlled conditions (same plant species, age, and environmental factors). Specific oligonucleotide primers were developed to identify Frankia Sp+ and/or Sp− strains in the resulting nodules. Single inoculation experiments showed that (i) infectivity by Sp+ strains was significantly greater than that by Sp− strains, (ii) genetically divergent Sp+ strains exhibited different infective abilities, and (iii) Sp+ and Sp− strains showed different host preferences according to the origin (host species) of the inocula. Co-inoculations of Sp+ and Sp− strains revealed the greater competitiveness of Sp+ strains (98.3 to 100% of Sp+ nodules, with up to 15.6% nodules containing both Sp+ and Sp− strains). The results of the present study highlight differences in Sp+/Sp− strain ecological behaviors and provide new insights to strengthen the obligate symbiont hypothesis for Sp+ strains. PMID:26726131

  4. Mexican papita viroid and tomato planta macho viroid belong to a single species in the genus Pospiviroid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato planta macho viroid (TPMVd) and Mexican papita viroid (MPVd) are two closely-related (>90% sequence identity) members of the genus Pospiviroid. Their current status as separate species is based upon the reported ability of TPMVd to replicate in Gomphrena globosa and the inability of this viro...

  5. An efficient method for visualization and growth of fluorescent Xanthomonas oryzae pv. oryzae in planta

    PubMed Central

    Han, Sang-Wook; Park, Chang-Jin; Lee, Sang-Won; Ronald, Pamela C

    2008-01-01

    Background Xanthomonas oryzae pv. oryzae, the causal agent of bacterial blight disease, is a serious pathogen of rice. Here we describe a fluorescent marker system to study virulence and pathogenicity of X. oryzae pv. oryzae. Results A fluorescent X. oryzae pv. oryzae Philippine race 6 strain expressing green fluorescent protein (GFP) (PXO99GFP) was generated using the gfp gene under the control of the neomycin promoter in the vector, pPneo-gfp. The PXO99GFPstrain displayed identical virulence and avirulence properties as the wild type control strain, PXO99. Using fluorescent microscopy, bacterial multiplication and colonization were directly observed in rice xylem vessels. Accurate and rapid determination of bacterial growth was assessed using fluoremetry and an Enzyme-Linked ImmunoSorbant Assay (ELISA). Conclusion Our results indicate that the fluorescent marker system is useful for assessing bacterial infection and monitoring bacterial multiplication in planta. PMID:18826644

  6. In Planta Response of Arabidopsis to Photothermal Impact Mediated by Gold Nanoparticles.

    PubMed

    Koo, Yeonjong; Lukianova-Hleb, Ekaterina Y; Pan, Joann; Thompson, Sean M; Lapotko, Dmitri O; Braam, Janet

    2016-02-01

    Biological responses to photothermal effects of gold nanoparticles (GNPs) have been demonstrated and employed for various applications in diverse systems except for one important class - plants. Here, the uptake of GNPs through Arabidopsis thaliana roots and translocation to leaves are reported. Successful plasmonic nanobubble generation and acoustic signal detection in planta is demonstrated. Furthermore, Arabidopsis leaves harboring GNPs and exposed to continuous laser or noncoherent light show elevated temperatures across the leaf surface and induced expression of heat-shock regulated genes. Overall, these results demonstrate that Arabidopsis can readily take up GNPs through the roots and translocate the particles to leaf tissues. Once within leaves, GNPs can act as photothermal agents for on-demand remote activation of localized biological processes in plants. PMID:26662357

  7. In Planta Microsphere-Based Lateral Flow Leaf Biosensor in Maize.

    PubMed

    Wen, Jessica T; Castro, Carlos; Tsutsui, Hideaki

    2015-08-01

    Low-cost and quick detection of biotic stresses is critically important for protection of staple food crops such as maize in smallholder farms in developing countries, where access to improved seed varieties, fertilizers, and pesticides is limited due to financial and geographical reasons. Here, we report a new lateral flow detection technology directly integrated in a maize leaf, in which microspheres conjugated with analyte-specific capture antibodies are non-invasively injected. The antibody-conjugated microspheres capture and detect an analyte in a concentration-specific manner. In this study, we optimized microsphere size for effective infiltration and immobilization in the leaf, and further demonstrated detection of a fluorescent mock biomarker, fluorescein, in a live maize plant. This in planta lateral flow biosensor is the first of its kind and is expected to provide a low-cost and user-friendly detection method for biotic stresses in the field. PMID:25271045

  8. In planta transformation method for T-DNA transfer in orchids

    NASA Astrophysics Data System (ADS)

    Semiarti, Endang; Purwantoro, Aziz; Mercuriani, Ixora S.; Anggriasari, Anida M.; Jang, Seonghoe; Suhandono, Sony; Machida, Yasunori; Machida, Chiyoko

    2014-03-01

    Transgenic plant technology is an efficient tool to study the function of gene(s) in plant. The most popular and widely used technique is Agrobacterium-mediated transformation in which cocultivation was done by immersing the plant tissues/organ in overnight bacterial cultured for about 30 minutes to one hour under in vitro condition. In this experiment, we developed more easier technique that omitted the in vitro step during cocultivation with Agrobacterium, namely in planta transformation method. Pollinaria (compact pollen mass of orchid) of Phalaenopsis amabilis and Spathoglottis plicata orchids were used as target explants that were immersed into bacterial culture for 30 minutes, then dried up the pollinaria, the transformed pollinaria was used to pollinate orchid flowers. The T-DNA used for this experiments were Ubipro∷PaFT/A. tumefaciens GV3101 for P. amabilis and MeEF1α2 pro∷GUS/ A. tumefaciens LBA 4404 for S.plicata. Seeds that were produced from pollinated flowers were grown onto 10 mg/l hygromicin containing NP (New Phalaenopsis) medium. The existance of transgene in putative transformant protocorm (developing orchid embryo) genome was confirmed using PCR with specific primers of either PaFT or GUS genes. Histochemical GUS assay was also performed to the putative transformants. The result showed that transformation frequencies were 2.1 % in P. amabilis, and 0,53% in S. plicata. These results indicates that in planta transformation method could be used for Agrobacterium-mediated genetic transformation, with advantage easier and more secure work from contaminants than that of the in vitro method.

  9. Detection and visualization of an exopolysaccharide produced by Xylella fastidiosa in vitro and in planta.

    PubMed

    Roper, M Caroline; Greve, L Carl; Labavitch, John M; Kirkpatrick, Bruce C

    2007-11-01

    Many phytopathogenic bacteria, such as Ralstonia solanacearum, Pantoea stewartii, and Xanthomonas campestris, produce exopolysaccharides (EPSs) that aid in virulence, colonization, and survival. EPS can also contribute to host xylem vessel blockage. The genome of Xylella fastidiosa, the causal agent of Pierce's disease (PD) of grapevine, contains an operon that is strikingly similar to the X. campestris gum operon, which is responsible for the production of xanthan gum. Based on this information, it has been hypothesized that X. fastidiosa is capable of producing an EPS similar in structure and composition to xanthan gum but lacking the terminal mannose residue. In this study, we raised polyclonal antibodies against a modified xanthan gum polymer similar to the predicted X. fastidiosa EPS polymer. We used enzyme-linked immunosorbent assay to quantify production of EPS from X. fastidiosa cells grown in vitro and immunolocalization microscopy to examine the distribution of X. fastidiosa EPS in biofilms formed in vitro and in planta and assessed the contribution of X. fastidiosa EPS to the vascular occlusions seen in PD-infected grapevines. PMID:17827325

  10. Cloning of immunodominant membrane protein genes of phytoplasmas and their in planta expression.

    PubMed

    Kakizawa, Shigeyuki; Oshima, Kenro; Ishii, Yoshiko; Hoshi, Ayaka; Maejima, Kensaku; Jung, Hee-Young; Yamaji, Yasuyuki; Namba, Shigetou

    2009-04-01

    Phytoplasmas are plant pathogenic bacteria that cause devastating yield losses in diverse crops worldwide. Although the understanding of the pathogen biology is important in agriculture, the inability to culture phytoplasmas has hindered their full characterization. Previous studies demonstrated that immunodominant membrane proteins could be classified into three types, immunodominant membrane protein (Imp), immunodominant membrane protein A (IdpA), and antigenic membrane protein (Amp), and they are nonhomologous to each other. Here, cloning and sequencing of imp-containing genomic fragments were performed for several groups of phytoplasma including the aster yellows and rice yellow dwarf groups, for which an imp sequence has not previously been reported. Sequence comparison analysis revealed that Imps are highly variable among phytoplasmas, and clear positive selection was observed in several Imps, suggesting that Imp has important roles in host-phytoplasma interactions. As onion yellows (OY) phytoplasma was known to have Amp as the immunodominant membrane protein, the protein accumulation level of Imp in planta was measured compared with that of Amp. The resulting accumulation of Imp was calculated as approximately one-tenth that of Amp, being consistent with the immunodominant property of Amp in OY. It is suggested that an ancestral type of immunodominant membrane protein could be Imp, and subsequently the expression level of Amp or IdpA is increased in several phytoplasma groups. PMID:19222574

  11. Development of 4-methoxy-7-nitroindolinyl (MNI)-caged auxins which are extremely stable in planta.

    PubMed

    Hayashi, Ken-Ichiro; Kusaka, Naoyuki; Yamasaki, Soma; Zhao, Yunde; Nozaki, Hiroshi

    2015-10-15

    Phytohormone auxin is a master regulator in plant growth and development. Regulation of cellular auxin level plays a central role in plant development. Auxin polar transport system modulates an auxin gradient that determines plant developmental process in response to environmental conditions and developmental programs. Photolabile caged auxins allow optical control of artificial auxin gradients at cellular resolution. Especially, two-photon uncaging system achieves high spatiotemporal control of photolysis reaction at two-photon cross-section. However, the development of caged versions of auxin has been limited by the instability of the caged auxins to higher plant metabolic activities. Here, we describe the synthesis and application of highly stable caged auxins, 4-methoxy-7-nitroindolinyl (MNI)-caged auxins. Natural auxin, indole 3-acetic acid, and two synthetic auxins, 1-NAA and 2,4-D were caged by MNI caging group. MNI-caged auxins showed a high stability in planta and a rapid release the original auxin when photolyzed. We demonstrated that optical control of auxin-responsive gene expression and auxin-related physiological responses by using MNI-caged auxins. We anticipate that MNI-caged auxins will be an effective tool for high-resolution control of endogenous auxin level. PMID:26364943

  12. Development of 4-methoxy-7-nitroindolinyl (MNI)-caged auxins which are extremely stable in planta

    PubMed Central

    Hayashi, Ken-ichiro; Kusaka, Naoyuki; Yamasaki, Soma; Zhao, Yunde; Nozaki, Hiroshi

    2015-01-01

    Phytohormone auxin is a master regulator in plant growth and development. Regulation of cellular auxin level plays a central role in plant development. Auxin polar transport system modulates an auxin gradient that determines plant developmental process in response to environmental conditions and developmental programs. Photolabile caged auxins allow optical control of artificial auxin gradients at cellular resolution. Especially, two-photon uncaging system achieves high spatiotemporal control of photolysis reaction at two-photon cross-section. However, the development of caged versions of auxin has been limited by the instability of the caged auxins to higher plant metabolic activities. Here, we describe the synthesis and application of highly stable caged auxins, 4-methoxy-7-nitroindolinyl (MNI)-caged auxins. Natural auxin, indole 3-acetic acid, and two synthetic auxins, 1-NAA and 2,4-D were caged by MNI caging group. MNI-caged auxins showed a high stability in planta and a rapid release the original auxin when photolyzed. We demonstrated that optical control of auxin-responsive gene expression and auxin-related physiological responses by using MNI-caged auxins. We anticipate that MNI-caged auxins will be an effective tool for high-resolution control of endogenous auxin level. PMID:26364943

  13. TYLCV-Is movement in planta does not require V2 protein

    SciTech Connect

    Hak, Hagit; Levy, Yael; Chandran, Sam A.; Belausov, Eduard; Loyter, Abraham; Lapidot, Moshe; Gafni, Yedidya

    2015-03-15

    Tomato yellow leaf curl virus (TYLCV), a major tomato pathogen causing extensive crop losses, is a whitefly-transmitted geminivirus. V2 mutants of TYLCV-Is and related viruses tend to induce symptomless infection with attenuated viral DNA levels, while accumulating close to wild-type DNA levels in protoplasts, suggesting V2 as a movement protein. The discovery of plant-silencing mechanisms and viral silencing suppressors, V2 included, led us to reconsider V2's involvement in viral movement. We studied two mutant versions of the virus, one impaired in V2 silencing-suppression activity, and another carrying a non-translatable V2. While both mutant viruses spread in the infected plant to newly emerged leaves at the same rate as the wild-type virus, their DNA-accumulation levels were tenfold lower than in the wild-type virus. Thus, we suggest that the setback in virus proliferation, previously ascribed to a movement impediment, is due to lack of silencing-suppression activity. - Highlights: • TYLCV-Is V2 protein is localized in distinct microbodies throughout the cell cytoplasm, around the nucleus and in association with cytoplasmic strands but is not associated with the plasmodesmata. • Disruption of RNA-silencing suppression activity of TYLCV-Is V2 protein causes low titer of the virus in the infected plants. • The movement of TYLCV-Is in planta does not require a functional V2 protein.

  14. Cytorhabdovirus P protein suppresses RISC-mediated cleavage and RNA silencing amplification in planta.

    PubMed

    Mann, Krin S; Johnson, Karyn N; Carroll, Bernard J; Dietzgen, Ralf G

    2016-03-01

    Plant viruses have evolved to undermine the RNA silencing pathway by expressing suppressor protein(s) that interfere with one or more key components of this antiviral defense. Here we show that the recently identified RNA silencing suppressor (RSS) of lettuce necrotic yellows virus (LNYV), phosphoprotein P, binds to RNA silencing machinery proteins AGO1, AGO2, AGO4, RDR6 and SGS3 in protein-protein interaction assays when transiently expressed. In planta, we demonstrate that LNYV P inhibits miRNA-guided AGO1 cleavage and translational repression, and RDR6/SGS3-dependent amplification of silencing. Analysis of LNYV P deletion mutants identified a C-terminal protein domain essential for both local RNA silencing suppression and interaction with AGO1, AGO2, AGO4, RDR6 and SGS3. In contrast to other viral RSS known to disrupt AGO activity, LNYV P sequence does not contain any recognizable GW/WG or F-box motifs. This suggests that LNYV P may represent a new class of AGO binding proteins. PMID:26808923

  15. Advances in alfalfa mosaic virus-mediated expression of anthrax antigen in planta

    SciTech Connect

    Brodzik, R.; Bandurska, K.; Deka, D.; Golovkin, M.; Koprowski, H. . E-mail: h_koprowski@jefferson.edu

    2005-12-16

    Plant viruses show great potential for production of pharmaceuticals in plants. Such viruses can harbor a small antigenic peptide(s) as a part of their coat proteins (CP) and elicit an antigen-specific immune response. Here, we report the high yield and consistency in production of recombinant alfalfa mosaic virus (AlMV) particles for specific presentation of the small loop 15 amino acid epitope from domain-4 of the Bacillus anthracis protective antigen (PA-D4s). The epitope was inserted immediately after the first 25 N-terminal amino acids of AlMV CP to retain genome activation and binding of CP to viral RNAs. Recombinant AlMV particles were efficiently produced in tobacco, easily purified for immunological analysis, and exhibited extended stability and systemic proliferation in planta. Intraperitional injections of mice with recombinant plant virus particles harboring the PA-D4s epitope elicited a distinct immune response. Western blotting and ELISA analysis showed that sera from immunized mice recognized both native PA antigen and the AlMV CP.

  16. Analysis of in planta Expressed Orphan Genes in the Rice Blast Fungus Magnaporthe oryzae

    PubMed Central

    Sadat, Abu; Jeon, Junhyun; Mir, Albely Afifa; Kim, Seongbeom; Choi, Jaeyoung; Lee, Yong-Hwan

    2014-01-01

    Genomes contain a large number of unique genes which have not been found in other species. Although the origin of such “orphan” genes remains unclear, they are thought to be involved in species-specific adaptive processes. Here, we analyzed seven orphan genes (MoSPC1 to MoSPC7) prioritized based on in planta expressed sequence tag data in the rice blast fungus, Magnaporthe oryzae. Expression analysis using qRT-PCR confirmed the expression of four genes (MoSPC1, MoSPC2, MoSPC3 and MoSPC7) during plant infection. However, individual deletion mutants of these four genes did not differ from the wild-type strain for all phenotypes examined, including pathogenicity. The length, GC contents, codon adaptation index and expression during mycelial growth of the four genes suggest that these genes formed during the evolutionary history of M. oryzae. Synteny analyses using closely related fungal species corroborated the notion that these genes evolved de novo in the M. oryzae genome. In this report, we discuss our inability to detect phenotypic changes in the four deletion mutants. Based on these results, the four orphan genes may be products of de novo gene birth processes, and their adaptive potential is in the course of being tested for retention or extinction through natural selection. PMID:25506301

  17. Advances in alfalfa mosaic virus-mediated expression of anthrax antigen in planta.

    PubMed

    Brodzik, R; Bandurska, K; Deka, D; Golovkin, M; Koprowski, H

    2005-12-16

    Plant viruses show great potential for production of pharmaceuticals in plants. Such viruses can harbor a small antigenic peptide(s) as a part of their coat proteins (CP) and elicit an antigen-specific immune response. Here, we report the high yield and consistency in production of recombinant alfalfa mosaic virus (AlMV) particles for specific presentation of the small loop 15 amino acid epitope from domain-4 of the Bacillus anthracis protective antigen (PA-D4s). The epitope was inserted immediately after the first 25 N-terminal amino acids of AlMV CP to retain genome activation and binding of CP to viral RNAs. Recombinant AlMV particles were efficiently produced in tobacco, easily purified for immunological analysis, and exhibited extended stability and systemic proliferation in planta. Intraperitional injections of mice with recombinant plant virus particles harboring the PA-D4s epitope elicited a distinct immune response. Western blotting and ELISA analysis showed that sera from immunized mice recognized both native PA antigen and the AlMV CP. PMID:16236249

  18. In planta comparative transcriptomics of host-adapted strains of Ralstonia solanacearum.

    PubMed

    Ailloud, Florent; Lowe, Tiffany M; Robène, Isabelle; Cruveiller, Stéphane; Allen, Caitilyn; Prior, Philippe

    2016-01-01

    Background. Ralstonia solanacearum is an economically important plant pathogen with an unusually large host range. The Moko (banana) and NPB (not pathogenic to banana) strain groups are closely related but are adapted to distinct hosts. Previous comparative genomics studies uncovered very few differences that could account for the host range difference between these pathotypes. To better understand the basis of this host specificity, we used RNAseq to profile the transcriptomes of an R. solanacearum Moko strain and an NPB strain under in vitro and in planta conditions. Results. RNAs were sequenced from bacteria grown in rich and minimal media, and from bacteria extracted from mid-stage infected tomato, banana and melon plants. We computed differential expression between each pair of conditions to identify constitutive and host-specific gene expression differences between Moko and NPB. We found that type III secreted effectors were globally up-regulated upon plant cell contact in the NPB strain compared with the Moko strain. Genes encoding siderophore biosynthesis and nitrogen assimilation genes were highly up-regulated in the NPB strain during melon pathogenesis, while denitrification genes were up-regulated in the Moko strain during banana pathogenesis. The relatively lower expression of oxidases and the denitrification pathway during banana pathogenesis suggests that R. solanacearum experiences higher oxygen levels in banana pseudostems than in tomato or melon xylem. Conclusions. This study provides the first report of differential gene expression associated with host range variation. Despite minimal genomic divergence, the pathogenesis of Moko and NPB strains is characterized by striking differences in expression of virulence- and metabolism-related genes. PMID:26788428

  19. 3D domain swapping causes extensive multimerisation of human interleukin-10 when expressed in planta.

    PubMed

    Westerhof, Lotte B; Wilbers, Ruud H P; Roosien, Jan; van de Velde, Jan; Goverse, Aska; Bakker, Jaap; Schots, Arjen

    2012-01-01

    Heterologous expression platforms of biopharmaceutical proteins have been significantly improved over the last decade. Further improvement can be established by examining the intrinsic properties of proteins. Interleukin-10 (IL-10) is an anti-inflammatory cytokine with a short half-life that plays an important role in re-establishing immune homeostasis. This homodimeric protein of 36 kDa has significant therapeutic potential to treat inflammatory and autoimmune diseases. In this study we show that the major production bottleneck of human IL-10 is not protein instability as previously suggested, but extensive multimerisation due to its intrinsic 3D domain swapping characteristic. Extensive multimerisation of human IL-10 could be visualised as granules in planta. On the other hand, mouse IL-10 hardly multimerised, which could be largely attributed to its glycosylation. By introducing a short glycine-serine-linker between the fourth and fifth alpha helix of human IL-10 a stable monomeric form of IL-10 (hIL-10(mono)) was created that no longer multimerised and increased yield up to 20-fold. However, hIL-10(mono) no longer had the ability to reduce pro-inflammatory cytokine secretion from lipopolysaccharide-stimulated macrophages. Forcing dimerisation restored biological activity. This was achieved by fusing human IL-10(mono) to the C-terminal end of constant domains 2 and 3 of human immunoglobulin A (Fcα), a natural dimer. Stable dimeric forms of IL-10, like Fcα-IL-10, may not only be a better format for improved production, but also a more suitable format for medical applications. PMID:23049703

  20. In planta comparative transcriptomics of host-adapted strains of Ralstonia solanacearum

    PubMed Central

    Ailloud, Florent; Lowe, Tiffany M.; Robène, Isabelle; Cruveiller, Stéphane; Allen, Caitilyn

    2016-01-01

    Background. Ralstonia solanacearum is an economically important plant pathogen with an unusually large host range. The Moko (banana) and NPB (not pathogenic to banana) strain groups are closely related but are adapted to distinct hosts. Previous comparative genomics studies uncovered very few differences that could account for the host range difference between these pathotypes. To better understand the basis of this host specificity, we used RNAseq to profile the transcriptomes of an R. solanacearum Moko strain and an NPB strain under in vitro and in planta conditions. Results. RNAs were sequenced from bacteria grown in rich and minimal media, and from bacteria extracted from mid-stage infected tomato, banana and melon plants. We computed differential expression between each pair of conditions to identify constitutive and host-specific gene expression differences between Moko and NPB. We found that type III secreted effectors were globally up-regulated upon plant cell contact in the NPB strain compared with the Moko strain. Genes encoding siderophore biosynthesis and nitrogen assimilation genes were highly up-regulated in the NPB strain during melon pathogenesis, while denitrification genes were up-regulated in the Moko strain during banana pathogenesis. The relatively lower expression of oxidases and the denitrification pathway during banana pathogenesis suggests that R. solanacearum experiences higher oxygen levels in banana pseudostems than in tomato or melon xylem. Conclusions. This study provides the first report of differential gene expression associated with host range variation. Despite minimal genomic divergence, the pathogenesis of Moko and NPB strains is characterized by striking differences in expression of virulence- and metabolism-related genes. PMID:26788428

  1. In planta reduction of maize seedling stalk lesions by the bacterial endophyte Bacillus mojavensis.

    PubMed

    Bacon, Charles W; Hinton, Dorothy M

    2011-06-01

    Maize (Zea mays L.) is susceptible to infection by Fusarium verticillioides through autoinfection and alloinfection, resulting in diseases and contamination of maize kernels with the fumonisin mycotoxins. Attempts at controlling this fungus are currently being done with biocontrol agents such as bacteria, and this includes bacterial endophytes, such as Bacillus mojavensis . In addition to producing fumonisins, which are phytotoxic and mycotoxic, F. verticillioides also produces fusaric acid, which acts both as a phytotoxin and as an antibiotic. The question now is Can B. mojavensis reduce lesion development in maize during the alloinfection process, simulated by internode injection of the fungus? Mutant strains of B. mojavensis that tolerate fusaric acid were used in a growth room study to determine the development of stalk lesions, indicative of maize seedling blight, by co-inoculations with a wild-type strain of F. verticillioides and with non-fusaric acid producing mutants of F. verticillioides. Lesions were measured on 14-day-old maize stalks consisting of treatment groups inoculated with and without mutants and wild-type strains of bacteria and fungi. The results indicate that the fusaric-acid-tolerant B. mojavensis mutant reduced stalk lesions, suggesting an in planta role for this substance as an antibiotic. Further, lesion development occurred in maize infected with F. verticillioides mutants that do not produce fusaric acid, indicating a role for other phytotoxins, such as the fumonisins. Thus, additional pathological components should be examined before strains of B. mojavensis can be identified as being effective as a biocontrol agent, particularly for the control of seedling disease of maize. PMID:21635192

  2. Bioinspired engineering study of Plantae vascules for self-healing composite structures.

    PubMed

    Trask, R S; Bond, I P

    2010-06-01

    This paper presents the first conceptual study into creating a Plantae-inspired vascular network within a fibre-reinforced polymer composite laminate, which provides an ongoing self-healing functionality without incurring a mass penalty. Through the application of a 'lost-wax' technique, orthogonal hollow vascules, inspired by the 'ray cell' structures found in ring porous hardwoods, were successfully introduced within a carbon fibre-reinforced epoxy polymer composite laminate. The influence on fibre architecture and mechanical behaviour of single vascules (located on the laminate centreline) when aligned parallel and transverse to the local host ply was characterized experimentally using a compression-after-impact test methodology. Ultrasonic C-scanning and high-resolution micro-CT X-ray was undertaken to identify the influence of and interaction between the internal vasculature and impact damage. The results clearly show that damage morphology is influenced by vascule orientation and that a 10 J low-velocity impact damage event is sufficient to breach the vasculature; a prerequisite for any subsequent self-healing function. The residual compressive strength after a 10 J impact was found to be dependent upon vascule orientation. In general, residual compressive strength decreased to 70 per cent of undamaged strength when vasculature was aligned parallel to the local host ply and a value of 63 per cent when aligned transverse. This bioinspired engineering study has illustrated the potential that a vasculature concept has to offer in terms of providing a self-healing function with minimum mass penalty, without initiating premature failure within a composite structure. PMID:19955122

  3. Bioinspired engineering study of Plantae vascules for self-healing composite structures

    PubMed Central

    Trask, R. S.; Bond, I. P.

    2010-01-01

    This paper presents the first conceptual study into creating a Plantae-inspired vascular network within a fibre-reinforced polymer composite laminate, which provides an ongoing self-healing functionality without incurring a mass penalty. Through the application of a ‘lost-wax’ technique, orthogonal hollow vascules, inspired by the ‘ray cell’ structures found in ring porous hardwoods, were successfully introduced within a carbon fibre-reinforced epoxy polymer composite laminate. The influence on fibre architecture and mechanical behaviour of single vascules (located on the laminate centreline) when aligned parallel and transverse to the local host ply was characterized experimentally using a compression-after-impact test methodology. Ultrasonic C-scanning and high-resolution micro-CT X-ray was undertaken to identify the influence of and interaction between the internal vasculature and impact damage. The results clearly show that damage morphology is influenced by vascule orientation and that a 10 J low-velocity impact damage event is sufficient to breach the vasculature; a prerequisite for any subsequent self-healing function. The residual compressive strength after a 10 J impact was found to be dependent upon vascule orientation. In general, residual compressive strength decreased to 70 per cent of undamaged strength when vasculature was aligned parallel to the local host ply and a value of 63 per cent when aligned transverse. This bioinspired engineering study has illustrated the potential that a vasculature concept has to offer in terms of providing a self-healing function with minimum mass penalty, without initiating premature failure within a composite structure. PMID:19955122

  4. Significant reduction of BiFC non-specific assembly facilitates in planta assessment of heterotrimeric G-protein interactors

    PubMed Central

    Gookin, Timothy E; Assmann, Sarah M

    2014-01-01

    Protein networks and signaling cascades are key mechanisms for intra- and intercellular signal transduction. Identifying the interacting partners of a protein can provide vital clues regarding its physiological role. The bimolecular fluorescence complementation (BiFC) assay has become a routine tool for in vivo analysis of protein–protein interactions and their subcellular location. Although the BiFC system has improved since its inception, the available options for in planta analysis are still subject to very low signal-to-noise ratios, and a systematic comparison of BiFC confounding background signals has been lacking. Background signals can obscure weak interactions, provide false positives, and decrease confidence in true positives. To overcome these problems, we performed an extensive in planta analysis of published BiFC fragments used in metazoa and plants, and then developed an optimized single vector BiFC system which utilizes monomeric Venus (mVenus) split at residue 210, and contains an integrated mTurquoise2 marker to precisely identify transformed cells in order to distinguish true negatives. Here we provide our streamlined double ORF expression (pDOE) BiFC system, and show that our advance in BiFC methodology functions even with an internally fused mVenus210 fragment. We illustrate the efficacy of the system by providing direct visualization of Arabidopsis MLO1 interacting with a calmodulin-like (CML) protein, and by showing that heterotrimeric G-protein subunits Gα (GPA1) and Gβ (AGB1) interact in plant cells. We further demonstrate that GPA1 and AGB1 each physically interact with PLDα1 in planta, and that mutation of the so-called PLDα1 ‘DRY’ motif abolishes both of these interactions. PMID:25187041

  5. Significant reduction of BiFC non-specific assembly facilitates in planta assessment of heterotrimeric G-protein interactors.

    PubMed

    Gookin, Timothy E; Assmann, Sarah M

    2014-11-01

    Protein networks and signaling cascades are key mechanisms for intra- and intercellular signal transduction. Identifying the interacting partners of a protein can provide vital clues regarding its physiological role. The bimolecular fluorescence complementation (BiFC) assay has become a routine tool for in vivo analysis of protein-protein interactions and their subcellular location. Although the BiFC system has improved since its inception, the available options for in planta analysis are still subject to very low signal-to-noise ratios, and a systematic comparison of BiFC confounding background signals has been lacking. Background signals can obscure weak interactions, provide false positives, and decrease confidence in true positives. To overcome these problems, we performed an extensive in planta analysis of published BiFC fragments used in metazoa and plants, and then developed an optimized single vector BiFC system which utilizes monomeric Venus (mVenus) split at residue 210, and contains an integrated mTurquoise2 marker to precisely identify transformed cells in order to distinguish true negatives. Here we provide our streamlined double ORF expression (pDOE) BiFC system, and show that our advance in BiFC methodology functions even with an internally fused mVenus210 fragment. We illustrate the efficacy of the system by providing direct visualization of Arabidopsis MLO1 interacting with a calmodulin-like (CML) protein, and by showing that heterotrimeric G-protein subunits Gα (GPA1) and Gβ (AGB1) interact in plant cells. We further demonstrate that GPA1 and AGB1 each physically interact with PLDα1 in planta, and that mutation of the so-called PLDα1 'DRY' motif abolishes both of these interactions. PMID:25187041

  6. Nodularin, a cyanobacterial toxin, is synthesized in planta by symbiotic Nostoc sp.

    PubMed

    Gehringer, Michelle M; Adler, Lewis; Roberts, Alexandra A; Moffitt, Michelle C; Mihali, Troco K; Mills, Toby J T; Fieker, Claus; Neilan, Brett A

    2012-10-01

    The nitrogen-fixing bacterium, Nostoc, is a commonly occurring cyanobacterium often found in symbiotic associations. We investigated the potential of cycad cyanobacterial endosymbionts to synthesize microcystin/nodularin. Endosymbiont DNA was screened for the aminotransferase domain of the toxin biosynthesis gene clusters. Five endosymbionts carrying the gene were screened for bioactivity. Extracts of two isolates inhibited protein phosphatase 2A and were further analyzed using electrospray ionization mass spectrometry (ESI-MS)/MS. Nostoc sp. 'Macrozamia riedlei 65.1' and Nostoc sp. 'Macrozamia serpentina 73.1' both contained nodularin. High performance liquid chromatography (HPLC) HESI-MS/MS analysis confirmed the presence of nodularin at 9.55±2.4 ng μg-1 chlorophyll a in Nostoc sp. 'Macrozamia riedlei 65.1' and 12.5±8.4 ng μg-1 Chl a in Nostoc sp. 'Macrozamia serpentina 73.1' extracts. Further scans indicated the presence of the rare isoform [L-Har(2)] nodularin, which contains L-homoarginine instead of L-arginine. Nodularin was also present at 1.34±0.74 ng ml(-1) (approximately 3 pmol per g plant ww) in the methanol root extracts of M. riedlei MZ65, while the presence of [L-Har(2)] nodularin in the roots of M. serpentina MZ73 was suggested by HPLC HESI-MS/MS analysis. The ndaA-B and ndaF genomic regions were sequenced to confirm the presence of the hybrid polyketide/non-ribosomal gene cluster. A seven amino-acid insertion into the NdaA-C1 domain of N. spumigena NSOR10 protein was observed in all endosymbiont-derived sequences, suggesting the transfer of the nda cluster from N. spumigena to terrestrial Nostoc species. This study demonstrates the synthesis of nodularin and [L-Har(2)] nodularin in a non-Nodularia species and the production of cyanobacterial hepatotoxin by a symbiont in planta. PMID:22456448

  7. In planta gene expression analysis of Xanthomonas oryzae pathovar oryzae, African strain MAI1

    PubMed Central

    2010-01-01

    Background Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo), induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc). Results Changes in gene expression of the African Xoo strain MAI1 in the susceptible rice cultivar Nipponbare were profiled, using an SSH Xoo DNA microarray. Microarray hybridization was performed comparing bacteria recovered from plant tissues at 1, 3, and 6 days after inoculation (dai) with bacteria grown in vitro. A total of 710 bacterial genes were found to be differentially expressed, with 407 up-regulated and 303 down-regulated. Expression profiling indicated that less than 20% of the 710 bacterial transcripts were induced in the first 24 h after inoculation, whereas 63% were differentially expressed at 6 dai. The 710 differentially expressed genes were one-end sequenced. 535 sequences were obtained from which 147 non-redundant sequences were identified. Differentially expressed genes were related to metabolism, secretion and transport, pathogen adherence to plant tissues, plant cell-wall degradation, IS elements, and virulence. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. The Xoo MAI1 non-redundant set of sequences was compared against several X. oryzae genomes, revealing a specific group of genes that was present only in MAI1. Numerous IS elements were also found to be differentially expressed. Quantitative real-time PCR confirmed 86% of the identified profile on a set of 14 genes selected according to the microarray analysis. Conclusions This is the first report to compare the expression of Xoo genes in planta across different time points during infection. This work shows that as-yet-unidentified and

  8. In-planta sporulation phenotype: a major life history trait to understand the evolution of Alnus-infective Frankia strains.

    PubMed

    Pozzi, Adrien C; Bautista-Guerrero, Hector H; Nouioui, Imen; Cotin-Galvan, Laëtitia; Pepin, Régis; Fournier, Pascale; Menu, Frédéric; Fernandez, Maria P; Herrera-Belaroussi, Aude

    2015-09-01

    Two major types of Frankia strains are usually recognized, based on the ability to sporulate in-planta: spore-positive (Sp+) and spore-negative (Sp-). We carried out a study of Sp+ and Sp- Frankia strains based on nodules collected on Alnus glutinosa, Alnus incana and Alnus viridis. The nodules were phenotyped using improved histology methods, and endophytic Frankia strain genotype was determined using a multilocus sequence analysis approach. An additional sampling was done to assess the relation between Sp+ phenotype frequency and genetic diversity of Frankia strains at the alder stand scale. Our results revealed that (i) Sp+ and Sp- Alnus-infective Frankia strains are genetically different even when sampled from the same alder stand and the same host-plant species; (ii) there are at least two distinct phylogenetic lineages of Sp+ Frankia that cluster according to the host-plant species and without regard of geographic distance and (iii) genetic diversity of Sp+ strains is very low at the alder stand scale compared with Sp- strains. Difference in evolutionary history and genetic diversity between Sp+ and Sp- Frankia allows us to discuss the possible ecological role of in-planta sporulation. PMID:25335453

  9. In planta expression of A. cellulolyticus Cel5A endocellulase reduces cell wall recalcitrance in tobacco and maize

    PubMed Central

    2011-01-01

    The glycoside hydrolase family 5 endocellulase, E1 (Cel5A), from Acidothermus cellulolyticus was transformed into both Nicotiana tabacum and Zea mays with expression targeted to the cell wall under a constitutive promoter. Here we explore the possibility that in planta expression of endocellulases will allow these enzymes to access their substrates during cell wall construction, rendering cellulose more amenable to pretreatment and enzyme digestion. Tobacco and maize plants were healthy and developed normally compared with the wild type (WT). After thermochemical pretreatment and enzyme digestion, transformed plants were clearly more digestible than WT, requiring lower pretreatment severity to achieve comparable conversion levels. Furthermore, the decreased recalcitrance was not due to post-pretreatment residual E1 activity and could not be reproduced by the addition of exogenous E1 to the biomass prior to pretreatment, indicating that the expression of E1 during cell wall construction altered the inherent recalcitrance of the cell wall. PMID:21269444

  10. Plastid-localized amino acid biosynthetic pathways of Plantae are predominantly composed of non-cyanobacterial enzymes

    PubMed Central

    Reyes-Prieto, Adrian; Moustafa, Ahmed

    2012-01-01

    Studies of photosynthetic eukaryotes have revealed that the evolution of plastids from cyanobacteria involved the recruitment of non-cyanobacterial proteins. Our phylogenetic survey of >100 Arabidopsis nuclear-encoded plastid enzymes involved in amino acid biosynthesis identified only 21 unambiguous cyanobacterial-derived proteins. Some of the several non-cyanobacterial plastid enzymes have a shared phylogenetic origin in the three Plantae lineages. We hypothesize that during the evolution of plastids some enzymes encoded in the host nuclear genome were mistargeted into the plastid. Then, the activity of those foreign enzymes was sustained by both the plastid metabolites and interactions with the native cyanobacterial enzymes. Some of the novel enzymatic activities were favored by selective compartmentation of additional complementary enzymes. The mosaic phylogenetic composition of the plastid amino acid biosynthetic pathways and the reduced number of plastid-encoded proteins of non-cyanobacterial origin suggest that enzyme recruitment underlies the recompartmentation of metabolic routes during the evolution of plastids. PMID:23233874

  11. Phytohormonal networks promote differentiation of fiber initials on pre-anthesis cotton ovules grown in vitro and in planta.

    PubMed

    Kim, Hee Jin; Hinchliffe, Doug J; Triplett, Barbara A; Chen, Z Jeffrey; Stelly, David M; Yeater, Kathleen M; Moon, Hong S; Gilbert, Matthew K; Thyssen, Gregory N; Turley, Rickie B; Fang, David D

    2015-01-01

    The number of cotton (Gossypium sp.) ovule epidermal cells differentiating into fiber initials is an important factor affecting cotton yield and fiber quality. Despite extensive efforts in determining the molecular mechanisms regulating fiber initial differentiation, only a few genes responsible for fiber initial differentiation have been discovered. To identify putative genes directly involved in the fiber initiation process, we used a cotton ovule culture technique that controls the timing of fiber initial differentiation by exogenous phytohormone application in combination with comparative expression analyses between wild type and three fiberless mutants. The addition of exogenous auxin and gibberellins to pre-anthesis wild type ovules that did not have visible fiber initials increased the expression of genes affecting auxin, ethylene, ABA and jasmonic acid signaling pathways within 1 h after treatment. Most transcripts expressed differentially by the phytohormone treatment in vitro were also differentially expressed in the ovules of wild type and fiberless mutants that were grown in planta. In addition to MYB25-like, a gene that was previously shown to be associated with the differentiation of fiber initials, several other differentially expressed genes, including auxin/indole-3-acetic acid (AUX/IAA) involved in auxin signaling, ACC oxidase involved in ethylene biosynthesis, and abscisic acid (ABA) 8'-hydroxylase an enzyme that controls the rate of ABA catabolism, were co-regulated in the pre-anthesis ovules of both wild type and fiberless mutants. These results support the hypothesis that phytohormonal signaling networks regulate the temporal expression of genes responsible for differentiation of cotton fiber initials in vitro and in planta. PMID:25927364

  12. Development of fiber optic spectroscopy for in-vitro and in-planta detection of fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Liew, Oi Wah; Chen, Jun-Wei; Asundi, Anand K.

    2001-10-01

    The objective of this project is to apply photonics technology to bio-safety management of genetically modified (GM) plants. The conventional method for screening GM plants is through selection using antibiotic resistance markers. There is public concern with such approaches and these are associated with food safety issues, escape of antibiotic resistance genes to pathogenic microorganisms and interference with antibiotic therapy. Thus, the strategy taken in this project is to replace antibiotic resistance markers with fluorescent protein markers that allow for rapid and non-invasive optical screening of genetically modified plants. In this paper, fibre optic spectroscopy was developed to detect and quantify recombinant green (EGFP) and red (DsRED) fluorescent proteins in vitro and in planta. In vitro detection was first carried out to optimize the sensitivity of the optical system. The bacterial expression vectors carrying the coding regions of EGFP and DsRED were introduced into Escherichia coli host cells and fluorescent proteins were produced following induction with IPTG. Soluble EGFP and DsRED proteins were isolated from lysed bacterial cells and serially diluted for quantitative analysis by fibre optic spectroscopy using different light sources, namely, blue LED (475 nm), tungsten halogen (350 - 1000 nm) and double frequency Nd:YAG green laser (532 nm). Fluorescence near the expected emission wavelengths could be detected up to 320X dilution for EGFP and DsRED with blue LED and 532 nm green laser, respectively, as the excitation source. Tungsten halogen was found to be unsuitable for excitation of both EGFP and DsRED. EGFP was successfully purified by size separation under non-denaturing electrophoretic conditions and quantified. The minimum concentration of EGFP detectable with blue LED excitation was 5 mg/ml. To determine the capability of spectroscopy detection in planta, transgenic potato hairy roots and whole modified plant lines expressing the

  13. The application of laser microdissection to in planta gene expression profiling of the maize anthracnose stalk rot fungus Colletotrichum graminicola.

    PubMed

    Tang, Weihua; Coughlan, Sean; Crane, Edmund; Beatty, Mary; Duvick, Jon

    2006-11-01

    Laser microdissection (LM) offers a potential means for deep sampling of a fungal plant-pathogen transcriptome during the infection process using whole-genome DNA microarrays. The use of a fluorescent protein-expressing fungus can greatly facilitate the identification of fungal structures for LM sampling. However, fixation methods that preserve both tissue histology and protein fluorescence, and that also yield RNA of suitable quality for microarray applications, have not been reported. We developed a microwave-accelerated acetone fixation, paraffin-embedding method that fulfills these requirements and used it to prepare mature maize stalk tissues infected with an Anemonia majano cyan fluorescent protein-expressing isolate of the anthracnose stalk rot fungus Colletotrichum graminicola. We successfully used LM to isolate individual maize cells associated with C. graminicola hyphae at an early stage of infection. The LM-derived RNA, after two-round linear amplification, was of sufficient quality and quantity for global expression profiling using a fungal microarray. Comparing replicated LM samples representing an early stage of stalk cell infection with samples from in vitro-germinated conidia, we identified 437 and 370 C. graminicola genes showing significant up- or downregulation, respectively. We confirmed the differential expression of several representative transcripts by quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) and documented extensive overlap of this dataset with a PCR-subtraction library enriched for C. graminicola transcripts in planta. Our results demonstrate that LM is feasible for in planta pathogen expression profiling and can reveal clues about fungal genes involved in pathogenesis. The method in this report may be advantageous for visualizing a variety of cellular features that depend on a high degree of histochemical preservation and RNA integrity prior to LM. PMID:17073306

  14. In planta Transformed Cumin (Cuminum cyminum L.) Plants, Overexpressing the SbNHX1 Gene Showed Enhanced Salt Endurance.

    PubMed

    Pandey, Sonika; Patel, Manish Kumar; Mishra, Avinash; Jha, Bhavanath

    2016-01-01

    Cumin is an annual, herbaceous, medicinal, aromatic, spice glycophyte that contains diverse applications as a food and flavoring additive, and therapeutic agents. An efficient, less time consuming, Agrobacterium-mediated, a tissue culture-independent in planta genetic transformation method was established for the first time using cumin seeds. The SbNHX1 gene, cloned from an extreme halophyte Salicornia brachiata was transformed in cumin using optimized in planta transformation method. The SbNHX1 gene encodes a vacuolar Na+/H+ antiporter and is involved in the compartmentalization of excess Na+ ions into the vacuole and maintenance of ion homeostasis Transgenic cumin plants were confirmed by PCR using gene (SbNHX1, uidA and hptII) specific primers. The single gene integration event and overexpression of the gene were confirmed by Southern hybridization and competitive RT-PCR, respectively. Transgenic lines L3 and L13 showed high expression of the SbNHX1 gene compared to L6 whereas moderate expression was detected in L5 and L10 transgenic lines. Transgenic lines (L3, L5, L10 and L13), overexpressing the SbNHX1 gene, showed higher photosynthetic pigments (chlorophyll a, b and carotenoid), and lower electrolytic leakage, lipid peroxidation (MDA content) and proline content as compared to wild type plants under salinity stress. Though transgenic lines were also affected by salinity stress but performed better compared to WT plants. The ectopic expression of the SbNHX1 gene confirmed enhanced salinity stress tolerance in cumin as compared to wild type plants under stress condition. The present study is the first report of engineering salt tolerance in cumin, so far and the plant may be utilized for the cultivation in saline areas. PMID:27411057

  15. Phytohormonal Networks Promote Differentiation of Fiber Initials on Pre-Anthesis Cotton Ovules Grown In Vitro and In Planta

    PubMed Central

    Kim, Hee Jin; Hinchliffe, Doug J.; Triplett, Barbara A.; Chen, Z. Jeffrey; Stelly, David M.; Yeater, Kathleen M.; Moon, Hong S.; Gilbert, Matthew K.; Thyssen, Gregory N.; Turley, Rickie B.; Fang, David D.

    2015-01-01

    The number of cotton (Gossypium sp.) ovule epidermal cells differentiating into fiber initials is an important factor affecting cotton yield and fiber quality. Despite extensive efforts in determining the molecular mechanisms regulating fiber initial differentiation, only a few genes responsible for fiber initial differentiation have been discovered. To identify putative genes directly involved in the fiber initiation process, we used a cotton ovule culture technique that controls the timing of fiber initial differentiation by exogenous phytohormone application in combination with comparative expression analyses between wild type and three fiberless mutants. The addition of exogenous auxin and gibberellins to pre-anthesis wild type ovules that did not have visible fiber initials increased the expression of genes affecting auxin, ethylene, ABA and jasmonic acid signaling pathways within 1 h after treatment. Most transcripts expressed differentially by the phytohormone treatment in vitro were also differentially expressed in the ovules of wild type and fiberless mutants that were grown in planta. In addition to MYB25-like, a gene that was previously shown to be associated with the differentiation of fiber initials, several other differentially expressed genes, including auxin/indole-3-acetic acid (AUX/IAA) involved in auxin signaling, ACC oxidase involved in ethylene biosynthesis, and abscisic acid (ABA) 8'-hydroxylase an enzyme that controls the rate of ABA catabolism, were co-regulated in the pre-anthesis ovules of both wild type and fiberless mutants. These results support the hypothesis that phytohormonal signaling networks regulate the temporal expression of genes responsible for differentiation of cotton fiber initials in vitro and in planta. PMID:25927364

  16. In planta Transformed Cumin (Cuminum cyminum L.) Plants, Overexpressing the SbNHX1 Gene Showed Enhanced Salt Endurance

    PubMed Central

    Pandey, Sonika; Patel, Manish Kumar; Jha, Bhavanath

    2016-01-01

    Cumin is an annual, herbaceous, medicinal, aromatic, spice glycophyte that contains diverse applications as a food and flavoring additive, and therapeutic agents. An efficient, less time consuming, Agrobacterium-mediated, a tissue culture-independent in planta genetic transformation method was established for the first time using cumin seeds. The SbNHX1 gene, cloned from an extreme halophyte Salicornia brachiata was transformed in cumin using optimized in planta transformation method. The SbNHX1 gene encodes a vacuolar Na+/H+ antiporter and is involved in the compartmentalization of excess Na+ ions into the vacuole and maintenance of ion homeostasis Transgenic cumin plants were confirmed by PCR using gene (SbNHX1, uidA and hptII) specific primers. The single gene integration event and overexpression of the gene were confirmed by Southern hybridization and competitive RT-PCR, respectively. Transgenic lines L3 and L13 showed high expression of the SbNHX1 gene compared to L6 whereas moderate expression was detected in L5 and L10 transgenic lines. Transgenic lines (L3, L5, L10 and L13), overexpressing the SbNHX1 gene, showed higher photosynthetic pigments (chlorophyll a, b and carotenoid), and lower electrolytic leakage, lipid peroxidation (MDA content) and proline content as compared to wild type plants under salinity stress. Though transgenic lines were also affected by salinity stress but performed better compared to WT plants. The ectopic expression of the SbNHX1 gene confirmed enhanced salinity stress tolerance in cumin as compared to wild type plants under stress condition. The present study is the first report of engineering salt tolerance in cumin, so far and the plant may be utilized for the cultivation in saline areas. PMID:27411057

  17. Detection of plum pox potyviral protein-protein interactions in planta using an optimized mRFP-based bimolecular fluorescence complementation system.

    PubMed

    Zilian, Eva; Maiss, Edgar

    2011-12-01

    In previous studies, protein interaction maps of different potyviruses have been generated using yeast two-hybrid (YTH) systems, and these maps have demonstrated a high diversity of interactions of potyviral proteins. Using an optimized bimolecular fluorescence complementation (BiFC) system, a complete interaction matrix for proteins of a potyvirus was developed for the first time under in planta conditions with ten proteins from plum pox virus (PPV). In total, 52 of 100 possible interactions were detected, including the self-interactions of CI, 6K2, VPg, NIa-Pro, NIb and CP, which is more interactions than have ever been detected for any other potyvirus in a YTH approach. Moreover, the BiFC system was shown to be able to localize the protein interactions, which was typified for the protein self-interactions indicated above. Additionally, experiments were carried out with the P3N-PIPO protein, revealing an interaction with CI but not with CP and supporting the involvement of P3N-PIPO in the cell-to-cell movement of potyviruses. No self-interaction of the PPV helper component-proteinase (HC-Pro) was detected using BiFC in planta. Therefore, additional experiments with turnip mosaic virus (TuMV) HC-Pro, PPV_HC-Pro and their mutants were conducted. The self-interaction of TuMV_HCpro, as recently demonstrated, and the self-interaction of the TuMV_ and PPV_HC-Pro mutants were shown by BiFC in planta, indicating that HC-Pro self-interactions may be species-specific. BiFC is a very useful and reliable method for the detection and localization of protein interactions in planta, thus enabling investigations under more natural conditions than studies in yeast cells. PMID:21880839

  18. Functional characterisation of metal(loid) processes in planta through the integration of synchrotron techniques and plant molecular biology

    PubMed Central

    Donner, Erica; Punshon, Tracy; Guerinot, Mary Lou; Lombi, Enzo

    2013-01-01

    Functional characterisation of the genes regulating metal(loid) homeostasis in plants is a major focus of crop biofortification, phytoremediation, and food security research. This paper focuses on the potential for advancing plant metal(loid) research by combining molecular biology and synchrotron-based techniques. Recent advances in x-ray focussing optics and fluorescence detection have greatly improved the potential of synchrotron techniques for plant science research, allowing metal(loids) to be imaged in vivo in hydrated plant tissues at sub-micron resolution. Laterally resolved metal(loid) speciation can also be determined. By using molecular techniques to probe the location of gene expression and protein localisation and combining it with this synchrotron-derived data, functional information can be effectively and efficiently assigned to specific genes. This paper provides a review of the state of the art in this field, and provides examples as to how synchrotron-based methods can be combined with molecular techniques to facilitate functional characterisation of genes in planta. PMID:22200921

  19. Sucrose phosphate synthase and sucrose phosphate phosphatase interact in planta and promote plant growth and biomass accumulation

    PubMed Central

    Maloney, Victoria J.; Park, Ji-Young; Unda, Faride; Mansfield, Shawn D.

    2015-01-01

    Bioinformatic analysis indicates that sucrose phosphate synthase (SPS) contains a putative C-terminal sucrose phosphate phosphatase (SPP)-like domain that may facilitates the binding of SPP. If an SPS–SPP enzyme complex exists, it may provide sucrose biosynthesis with an additional level of regulation, forming a direct metabolic channel for sucrose-6-phosphate between these two enzymes. Herein, the formation of an enzyme complex between SPS and SPP was examined, and the results from yeast two-hybrid experiments suggest that there is indeed an association between these proteins. In addition, in planta bioluminescence resonance energy transfer (BRET) was observed in Arabidopsis seedlings, providing physical evidence for a protein interaction in live cells and in real time. Finally, bimolecular fluorescence complementation (BiFC) was employed in an attempt to detect SPS–SPP interactions visually. The findings clearly demonstrated that SPS interacts with SPP and that this interaction impacts soluble carbohydrate pools and affects carbon partitioning to starch. Moreover, a fusion construct between the two genes promotes plant growth in both transgenic Arabidopsis and hybrid poplar. PMID:25873678

  20. In Planta Single-Molecule Pull-Down Reveals Tetrameric Stoichiometry of HD-ZIPIII:LITTLE ZIPPER Complexes[OPEN

    PubMed Central

    Husbands, Aman Y.; Aggarwal, Vasudha; Ha, Taekjip; Timmermans, Marja C.P.

    2016-01-01

    Deciphering complex biological processes markedly benefits from approaches that directly assess the underlying biomolecular interactions. Most commonly used approaches to monitor protein-protein interactions typically provide nonquantitative readouts that lack statistical power and do not yield information on the heterogeneity or stoichiometry of protein complexes. Single-molecule pull-down (SiMPull) uses single-molecule fluorescence detection to mitigate these disadvantages and can quantitatively interrogate interactions between proteins and other compounds, such as nucleic acids, small molecule ligands, and lipids. Here, we establish SiMPull in plants using the HOMEODOMAIN LEUCINE ZIPPER III (HD-ZIPIII) and LITTLE ZIPPER (ZPR) interaction as proof-of-principle. Colocalization analysis of fluorophore-tagged HD-ZIPIII and ZPR proteins provides strong statistical evidence of complex formation. In addition, we use SiMPull to directly quantify YFP and mCherry maturation probabilities, showing these differ substantially from values obtained in mammalian systems. Leveraging these probabilities, in conjunction with fluorophore photobleaching assays on over 2000 individual complexes, we determined HD-ZIPIII:ZPR stoichiometry. Intriguingly, these complexes appear as heterotetramers, comprising two HD-ZIPIII and two ZPR molecules, rather than heterodimers as described in the current model. This surprising result raises new questions about the regulation of these key developmental factors and is illustrative of the unique contribution SiMPull is poised to make to in planta protein interaction studies. PMID:27385814

  1. Overexpression of the rice carotenoid cleavage dioxygenase 1 gene in Golden Rice endosperm suggests apocarotenoids as substrates in planta.

    PubMed

    Ilg, Andrea; Yu, Qiuju; Schaub, Patrick; Beyer, Peter; Al-Babili, Salim

    2010-08-01

    Carotenoids are converted by carotenoid cleavage dioxygenases that catalyze oxidative cleavage reactions leading to apocarotenoids. However, apocarotenoids can also be further truncated by some members of this enzyme family. The plant carotenoid cleavage dioxygenase 1 (CCD1) subfamily is known to degrade both carotenoids and apocarotenoids in vitro, leading to different volatile compounds. In this study, we investigated the impact of the rice CCD1 (OsCCD1) on the pigmentation of Golden Rice 2 (GR2), a genetically modified rice variety accumulating carotenoids in the endosperm. For this purpose, the corresponding cDNA was introduced into the rice genome under the control of an endosperm-specific promoter in sense and anti-sense orientations. Despite high expression levels of OsCCD1 in sense plants, pigment analysis revealed carotenoid levels and patterns comparable to those of GR2, pleading against carotenoids as substrates in rice endosperm. In support, similar carotenoid contents were determined in anti-sense plants. To check whether OsCCD1 overexpressed in GR2 endosperm is active, in vitro assays were performed with apocarotenoid substrates. HPLC analysis confirmed the cleavage activity of introduced OsCCD1. Our data indicate that apocarotenoids rather than carotenoids are the substrates of OsCCD1 in planta. PMID:20549230

  2. In planta chemical cross-linking and mass spectrometry analysis of protein structure and interaction in Arabidopsis.

    PubMed

    Zhu, Xinliang; Yu, Fengchao; Yang, Zhu; Liu, Shichang; Dai, Chen; Lu, Xiaoyun; Liu, Chenyu; Yu, Weichuan; Li, Ning

    2016-07-01

    Site-specific chemical cross-linking in combination with mass spectrometry analysis has emerged as a powerful proteomic approach for studying the three-dimensional structure of protein complexes and in mapping protein-protein interactions (PPIs). Building on the success of MS analysis of in vitro cross-linked proteins, which has been widely used to investigate specific interactions of bait proteins and their targets in various organisms, we report a workflow for in vivo chemical cross-linking and MS analysis in a multicellular eukaryote. This approach optimizes the in vivo protein cross-linking conditions in Arabidopsis thaliana, establishes a MudPIT procedure for the enrichment of cross-linked peptides, and develops an integrated software program, exhaustive cross-linked peptides identification tool (ECL), to identify the MS spectra of in planta chemical cross-linked peptides. In total, two pairs of in vivo cross-linked peptides of high confidence have been identified from two independent biological replicates. This work demarks the beginning of an alternative proteomic approach in the study of in vivo protein tertiary structure and PPIs in multicellular eukaryotes. PMID:27198063

  3. An optimized mRFP-based bimolecular fluorescence complementation system for the detection of protein-protein interactions in planta.

    PubMed

    Zilian, Eva; Maiss, Edgar

    2011-06-01

    An existing bimolecular fluorescence complementation (BiFC) system, based on a monomeric red fluorescent protein (mRFP), has been optimized for the investigation of protein-protein interactions in planta. The expression plasmids, encoding the N-terminal amino acids (aa) 1-168 and the C-terminal aa 169-225 of the mRFP, allow N- or C-terminal fusion of a split mRFP, with the genes of interest. Two major improvements over the original vectors have been made. Firstly, the coding sequence of a GGGSGGG-linker has been integrated between mRFP sequences and the genes of interest. Secondly, a modified mini binary vector (∼3.5 kb) was introduced as the backbone for the plant expression plasmids. Based on the results of yeast two-hybrid studies with plant viral proteins, interaction of viral proteins was tested in Nicotiana benthamiana plants and monitored by confocal laser scanning microscopy (CLSM). Plum pox virus coat protein and mutants thereof served as controls. The system was validated using the N-protein of Capsicum chlorosis virus for which a self-interaction was shown for the first time, the Tobacco mosaic virus coat protein and BC1 and BV1 of the Tomato yellow leaf curl Thailand virus. This optimized BiFC system provides a convenient alternative to other BiFC, as well as yeast two-hybrid assays, for detecting protein-protein interactions. PMID:21473882

  4. In planta transformation of sorghum (Sorghum bicolor (L.) Moench) using TPS1 gene for enhancing tolerance to abiotic stresses.

    PubMed

    Yellisetty, Varalaxmi; Reddy, L A; Mandapaka, Maheswari

    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 T 0 plants were chimeric and stable integration was observed in T1 generation. β-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. PMID:26440081

  5. Construction of EGFP-labeling system for visualizing the infection process of Xanthomonas axonopodis pv. citri in planta.

    PubMed

    Liu, Li-Ping; Deng, Zi-Niu; Qu, Jin-Wang; Yan, Jia-Wen; Catara, Vittoria; Li, Da-Zhi; Long, Gui-You; Li, Na

    2012-09-01

    Xanthomonas axonopodis pv. citri (Xac) is the causal agent of citrus bacterial canker, an economically important disease to world citrus industry. To monitor the infection process of Xac in different citrus plants, the enhanced green florescent protein (EGFP) visualizing system was constructed to visualize the propagation and localization in planta. First, the wild-type Xac was isolated from the diseased leaves of susceptible 'Bingtang' sweet orange, and then the isolated Xac was labeled with EGFP by triparental mating. After PCR identification, the growth kinetics and pathogenicity of the transformants were analyzed in comparison with the wild-type Xac. The EGFP-labeled bacteria were inoculated by spraying on the surface and infiltration in the mesophyll of 'Bingtang' sweet orange leaves. The bacterial cell multiplication and diffusion processes were observed directly under confocal laser scanning microscope at different intervals after inoculation. The results indicated that the EGFP-labeled Xac releasing clear green fluorescence light under fluorescent microscope showed the infection process and had the same pathogenicity as the wild type to citrus. Consequently, the labeled Xac demonstrated the ability as an efficient tool to monitor the pathogen infection. PMID:22674174

  6. In planta mechanism of action of leptospermone: impact of its physico-chemical properties on uptake, translocation, and metabolism.

    PubMed

    Owens, Daniel K; Nanayakkara, N P Dhammika; Dayan, Franck E

    2013-02-01

    Leptospermone is a natural β-triketone that specifically inhibits the enzyme p-hydrophyphenylpyruvate dioxygenase, the same molecular target site as that of the commercial herbicide mesotrione. The β-triketone-rich essential oil of Leptospermum scoparium has both preemergence and postemergence herbicidal activity, resulting in bleaching of treated plants and dramatic growth reduction. Radiolabeled leptospermone was synthesized to investigate the in planta mechanism of action of this natural herbicide. Approximately 50 % of the absorbed leptospermone was translocated to the foliage suggesting rapid acropetal movement of the molecule. On the other hand, very little leptospermone was translocated away from the point of application on the foliage, indicating poor phloem mobility. These observations are consistent with the physico-chemical properties of leptospermone, such as its experimentally measured logP and pK a values, and molecular mass, number of hydrogen donors and acceptors, and number of rotatable bonds. Consequently, leptospermone is taken up readily by roots and translocated to reach its molecular target site. This provides additional evidence that the anecdotal observation of allelopathic suppression of plant growth under β-triketone-producing species may be due to the release of these phytotoxins in soils. PMID:23314892

  7. Transient expression in Nicotiana benthamiana fluorescent marker lines provides enhanced definition of protein localization, movement and interactions in planta.

    PubMed

    Martin, Kathleen; Kopperud, Kristin; Chakrabarty, Romit; Banerjee, Rituparna; Brooks, Robert; Goodin, Michael M

    2009-07-01

    Here, we report on the construction of a novel series of Gateway-compatible plant transformation vectors containing genes encoding autofluorescent proteins, including Cerulean, Dendra2, DRONPA, TagRFP and Venus, for the expression of protein fusions in plant cells. To assist users in the selection of vectors, we have determined the relative in planta photostability and brightness of nine autofluorescent proteins (AFPs), and have compared the use of DRONPA and Dendra2 in photoactivation and photoconversion experiments. Additionally, we have generated transgenic Nicotiana benthamiana lines that express fluorescent protein markers targeted to nuclei, endoplasmic reticulum or actin filaments. We show that conducting bimolecular fluorescence complementation assays in plants that constitutively express cyan fluorescent protein fused to histone 2B provides enhanced data quality and content over assays conducted without the benefit of a subcellular marker. In addition to testing protein interactions, we demonstrate that our transgenic lines that express red fluorescent protein markers offer exceptional support in experiments aimed at defining nuclear or endomembrane localization. Taken together, the new combination of pSITE-BiFC and pSITEII vectors for studying intracellular protein interaction, localization and movement, in conjunction with our transgenic marker lines, constitute powerful tools for the plant biology community. PMID:19309457

  8. A rapid, highly efficient and economical method of Agrobacterium-mediated in planta transient transformation in living onion epidermis.

    PubMed

    Xu, Kedong; Huang, Xiaohui; Wu, Manman; Wang, Yan; Chang, Yunxia; Liu, Kun; Zhang, Ju; Zhang, Yi; Zhang, Fuli; Yi, Liming; Li, Tingting; Wang, Ruiyue; Tan, Guangxuan; Li, Chengwei

    2014-01-01

    Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale. PMID:24416168

  9. Positive-selection and ligation-independent cloning vectors for large scale in planta expression for plant functional genomics.

    PubMed

    Oh, Sang-Keun; Kim, Saet-Byul; Yeom, Seon-In; Lee, Hyun-Ah; Choi, Doil

    2010-12-01

    Transient expression is an easy, rapid and powerful technique for producing proteins of interest in plants. Recombinational cloning is highly efficient but has disadvantages, including complicated, time consuming cloning procedures and expensive enzymes for large-scale gene cloning. To overcome these limitations, we developed new ligation-independent cloning (LIC) vectors derived from binary vectors including tobacco mosaic virus (pJL-TRBO), potato virus X (pGR106) and the pBI121 vector-based pMBP1. LIC vectors were modified to enable directional cloning of PCR products without restriction enzyme digestion or ligation reactions. In addition, the ccdB gene, which encodes a potent cell-killing protein, was introduced between the two LIC adapter sites in the pJL-LIC, pGR-LIC, and pMBP-LIC vectors for the efficient selection of recombinant clones. This new vector does not require restriction enzymes, alkaline phosphatase, or DNA ligase for cloning. To clone, the three LIC vectors are digested with SnaBI and treated with T4 DNA polymerase, which includes 3' to 5' exonuclease activity in the presence of only one dNTP (dGTP for the inserts and dCTP for the vector). To make recombinants, the vector plasmid and the insert PCR fragment were annealed at room temperature for 20 min prior to transformation into the host. Bacterial transformation was accomplished with 100% efficiency. To validate the new LIC vector systems, we were used to coexpressed the Phytophthora AVR and potato resistance (R) genes in N. benthamiana by infiltration of Agrobacterium. Coexpressed AVR and R genes in N. benthamiana induced the typical hypersensitive cell death resulting from in vivo interaction of the two proteins. These LIC vectors could be efficiently used for high-throughput cloning and laboratory-scale in planta expression. These vectors could provide a powerful tool for high-throughput transient expression assays for functional genomic studies in plants. PMID:21340673

  10. In planta analysis of a cis-regulatory cytokinin response motif in Arabidopsis and identification of a novel enhancer sequence.

    PubMed

    Ramireddy, Eswarayya; Brenner, Wolfram G; Pfeifer, Andreas; Heyl, Alexander; Schmülling, Thomas

    2013-07-01

    The phytohormone cytokinin plays a key role in regulating plant growth and development, and is involved in numerous physiological responses to environmental changes. The type-B response regulators, which regulate the transcription of cytokinin response genes, are a part of the cytokinin signaling system. Arabidopsis thaliana encodes 11 type-B response regulators (type-B ARRs), and some of them were shown to bind in vitro to the core cytokinin response motif (CRM) 5'-(A/G)GAT(T/C)-3' or, in the case of ARR1, to an extended motif (ECRM), 5'-AAGAT(T/C)TT-3'. Here we obtained in planta proof for the functionality of the latter motif. Promoter deletion analysis of the primary cytokinin response gene ARR6 showed that a combination of two extended motifs within the promoter is required to mediate the full transcriptional activation by ARR1 and other type-B ARRs. CRMs were found to be over-represented in the vicinity of ECRMs in the promoters of cytokinin-regulated genes, suggesting their functional relevance. Moreover, an evolutionarily conserved 27 bp long T-rich region between -220 and -193 bp was identified and shown to be required for the full activation by type-B ARRs and the response to cytokinin. This novel enhancer is not bound by the DNA-binding domain of ARR1, indicating that additional proteins might be involved in mediating the transcriptional cytokinin response. Furthermore, genome-wide expression profiling identified genes, among them ARR16, whose induction by cytokinin depends on both ARR1 and other specific type-B ARRs. This together with the ECRM/CRM sequence clustering indicates cooperative action of different type-B ARRs for the activation of particular target genes. PMID:23620480

  11. Barcoding the kingdom Plantae: new PCR primers for ITS regions of plants with improved universality and specificity.

    PubMed

    Cheng, Tao; Xu, Chao; Lei, Li; Li, Changhao; Zhang, Yu; Zhou, Shiliang

    2016-01-01

    The internal transcribed spacer (ITS) of nuclear ribosomal DNA is one of the most commonly used DNA markers in plant phylogenetic and DNA barcoding analyses, and it has been recommended as a core plant DNA barcode. Despite this popularity, the universality and specificity of PCR primers for the ITS region are not satisfactory, resulting in amplification and sequencing difficulties. By thoroughly surveying and analysing the 18S, 5.8S and 26S sequences of Plantae and Fungi from GenBank, we designed new universal and plant-specific PCR primers for amplifying the whole ITS region and a part of it (ITS1 or ITS2) of plants. In silico analyses of the new and the existing ITS primers based on these highly representative data sets indicated that (i) the newly designed universal primers are suitable for over 95% of plants in most groups; and (ii) the plant-specific primers are suitable for over 85% of plants in most groups without amplification of fungi. A total of 335 samples from 219 angiosperm families, 11 gymnosperm families, 24 fern and lycophyte families, 16 moss families and 17 fungus families were used to test the performances of these primers. In vitro PCR produced similar results to those from the in silico analyses. Our new primer pairs gave PCR improvements up to 30% compared with common-used ones. The new universal ITS primers will find wide application in both plant and fungal biology, and the new plant-specific ITS primers will, by eliminating PCR amplification of nonplant templates, significantly improve the quality of ITS sequence information collections in plant molecular systematics and DNA barcoding. PMID:26084789

  12. Efficient In Planta Detection and Dissection of De Novo Mutation Events in the Arabidopsis thaliana Disease Resistance Gene UNI.

    PubMed

    Ogawa, Tomohiko; Mori, Akiko; Igari, Kadunari; Morita, Miyo Terao; Tasaka, Masao; Uchida, Naoyuki

    2016-06-01

    Plants possess disease resistance (R) proteins encoded by R genes, and each R protein recognizes a specific pathogen factor(s) for immunity. Interestingly, a remarkably high degree of polymorphisms in R genes, which are traces of past mutation events during evolution, suggest the rapid diversification of R genes. However, little is known about molecular aspects that facilitate the rapid change of R genes because of the lack of tools that enable us to monitor de novo R gene mutations efficiently in an experimentally feasible time scale, especially in living plants. Here we introduce a model assay system that enables efficient in planta detection of de novo mutation events in the Arabidopsis thaliana R gene UNI in one generation. The uni-1D mutant harbors a gain-of-function allele of the UNI gene. uni-1D heterozygous individuals originally exhibit dwarfism with abnormally short stems. However, interestingly, morphologically normal stems sometimes emerge spontaneously from the uni-1D plants, and the morphologically reverted tissues carry additional de novo mutations in the UNI gene. Strikingly, under an extreme condition, almost half of the examined population shows the reversion phenomenon. By taking advantage of this phenomenon, we demonstrate that the reversion frequency is remarkably sensitive to a variety of fluctuations in DNA stability, underlying a mutable tendency of the UNI gene. We also reveal that activities of the salicylic acid pathway and DNA damage sensor pathway are involved in the reversion phenomenon. Thus, we provide an experimentally feasible model tool to explore factors and conditions that significantly affect the R gene mutation phenomenon. PMID:27016096

  13. Astronomy at School: Measurements of the Earth-Moon Distance. (Spanish Title: Astronomía en la Escuela: Medición de la Distancia Tierra-Luna.) Astronomia na Escola: Medida da Distância Terra-Lua

    NASA Astrophysics Data System (ADS)

    Paolantonio, Santiago; Pintado, Olga I.

    2006-12-01

    The aim of this project is to approach High School students to Science. We propose to measure the Earth-Moon distance using the parallax. The observation and measurements techniques and all the calculations needed are described in this paper. The results obtained in a test experience realized during 2003 are presented. This test shows that this is a feasible project and also shows which things needed to be improved. Se plantea la propuesta de un proyecto educativo dirigido al Nivel Medio de enseñanza, consistente en la determinación de la distancia Tierra - Luna por paralaje. Se describen las técnicas de observación, mediciones y cálculos. Se proporcionan a continuación los resultados obtenidos en la experiencia piloto realizada en el 2003, la que permitió comprobar la factibilidad de llevar a cabo la propuesta, así como perfeccionar los diferentes aspectos involucrados en la misma. Propomos neste trabalho um projeto educativo dirigido ao Ensino Médio que consiste na determinação da distância Terra-Lua pelo efeito da paralaxe. As técnicas de observação, medidas e cálculos auxiliares são descritos, e os resultados obtidos numa experiência-teste realizada no ano de 2003 apresentados. Este último teste permitiu comprovar a viabilidade de execução da proposta e aperfeiçoar diversos aspectos da mesma.

  14. Bikinin-like inhibitors targeting GSK3/Shaggy-like kinases: characterisation of novel compounds and elucidation of their catabolism in planta

    PubMed Central

    2014-01-01

    Background Plant GSK-3/Shaggy-like kinases are key players in brassinosteroid (BR) signalling which impact on plant development and participate in response to wounding, pathogens and salt stress. Bikinin was previously identified in a chemical genetics screen as an inhibitor targeting these kinases. To dissect the structural elements crucial for inhibition of GSK-3/Shaggy-like kinases by bikinin and to isolate more potent compounds we synthesised a number of related substances and tested their inhibitory activity in vitro and in vivo using Arabidopsis thaliana. Results A pyridine ring with an amido succinic acid residue in position 2 and a halogen in position 5 were crucial for inhibitory activity. The compound with an iodine substituent in position 5, denoted iodobikinin, was most active in inhibiting BIN2 activity in vitro and efficiently induced brassinosteroid-like responses in vivo. Its methyl ester, methyliodobikinin, showed improved cell permeability, making it highly potent in vivo although it had lower activity in vitro. HPLC analysis revealed that the methyl residue was rapidly cleaved off in planta liberating active iodobikinin. In addition, we provide evidence that iodobikinin and bikinin are inactivated in planta by conjugation with glutamic acid or malic acid and that the latter process is catalysed by the malate transferase SNG1. Conclusion Brassinosteroids participate in regulation of many aspects of plant development and in responses to environmental cues. Thus compounds modulating their action are valuable tools to study such processes and may be an interesting opportunity to modify plant growth and performance in horticulture and agronomy. Here we report the development of bikinin derivatives with increased potency that can activate BR signalling and mimic BR action. Methyliodobikinin was 3.4 times more active in vivo than bikinin. The main reason for the superior activity of methyliodobikinin, the most potent compound, is its enhanced plant

  15. Fruta Planta label

    Center for Drug Evaluation (CDER)

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  16. Use of attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy in direct, non-destructive, and rapid assessment of developmental cotton fibers grown in planta and in culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton fibers are routinely harvested from cotton plants (in planta), and their end-use qualities depend on their development stages. Cotton fibers are also cultured at controlled laboratory environments, so that cotton researchers can investigate many aspects of experimental protocols in cotton bre...

  17. Transient Expression of Secretory IgA In Planta is Optimal Using a Multi-Gene Vector and may be Further Enhanced by Improving Joining Chain Incorporation

    PubMed Central

    Westerhof, Lotte B.; Wilbers, Ruud H. P.; van Raaij, Debbie R.; van Wijk, Christina Z.; Goverse, Aska; Bakker, Jaap; Schots, Arjen

    2016-01-01

    Secretory IgA (sIgA) is a crucial antibody in host defense at mucosal surfaces. It is a promising antibody isotype in a variety of therapeutic settings such as passive vaccination and treatment of inflammatory disorders. However, heterologous production of this heteromultimeric protein complex is still suboptimal. The challenge is the coordinate expression of the four required polypeptides; the alpha heavy chain, the light chain, the joining chain, and part of the polymeric-Ig-receptor called the secretory component, in a 4:4:1:1 ratio. We evaluated the transient expression of three sIgAκ variants, harboring the heavy chain isotype α1, α2m1, or α2m2, of the clinical antibody Ustekinumab in planta. Ustekinumab is directed against the p40 subunit that is shared by the pro-inflammatory cytokines interleukin (IL)-12 and IL-23. A sIgA variant of this antibody may enable localized treatment of inflammatory bowel disease. Of the three different sIgA variants we obtained the highest yield with sIgA1κ reaching up to 373 μg sIgA/mg total soluble protein. The use of a multi-cassette vector containing all four expression cassettes was most efficient. However, not the expression strategy, but the incorporation of the joining chain turned out to be the limiting step for sIgA production. Our data demonstrate that transient expression in planta is suitable for the economic production of heteromultimeric protein complexes such as sIgA. PMID:26793201

  18. La problematica de la demarcacion entre ciencia y pseudociencia y sus implicaciones en la educacion cientifica

    NASA Astrophysics Data System (ADS)

    Jimenez Tolentino, Dinorah

    2011-12-01

    En la sociedad prevalece una tendencia generalizada hacia la inclusion de creencias y practicas pseudocientificas. Esta investigacion responde a la necesidad de analizar como la proliferacion de las pseudociencias afecta la vision que tienen los estudiantes universitarios sobre las ciencias naturales. A tales efectos, la investigadora describe las concepciones epistemologicas que tienen los estudiantes sobre las ciencias y las pseudociencias e identifica los criterios de demarcacion, entre un area y otra, que se derivan de estas concepciones. De igual modo, esta identifica las creencias y practicas pseudocientificas de mayor arraigo entre los estudiantes, destacando, a su vez, la razon de ser de las mismas. Por ultimo, la investigadora analiza las implicaciones educativas de la problematica de la demarcacion entre ciencia y pseudociencia. La investigacion es de naturaleza mixta, enmarcada en los paradigmas empirico- analitico y cualitativo. El proceso investigativo se llevo a cabo mediante la administracion del cuestionario Criterios para la demarcacion entre ciencia y pseudociencia. La parte cualitativa estuvo enmarcada en el diseno de estudio de caso, recopilando informacion mediante entrevistas semiestructuradas en dos grupos focales. La poblacion de estudio estuvo constituida por estudiantes universitarios del nivel subgraduado de la Universidad Central de Bayamon. Los resultados del estudio reflejaron las concepciones erroneas de los estudiantes sobre la naturaleza de las ciencias y las pseudociencias. Con respecto a la demarcacion entre ciencia y pseudociencia, el criterio imperante entre los universitarios es el de la verificabilidad, considerando la aplicacion del metodo cientifico como el metodo para demostrar la veracidad de las teorias cientificas. Las creencias y practicas pseudocientificas no son muy frecuentes entre los universitarios. Estos atribuyen las mismas a la prevalencia de elementos supersticiosos y al engano a que es sometida la poblacion

  19. Entre Dos Mundos/Between Two Worlds: Youth Violence Prevention for Acculturating Latino Families

    ERIC Educational Resources Information Center

    Smokowski, Paul R.; Bacallao, Martica

    2009-01-01

    Objective: This study evaluated the efficacy of Entre Dos Mundos/Between Two Worlds (EDM) prevention for Latino adolescents. Method: In an experimental trial to compare implementation formats, 41 Latino families were randomly assigned to EDM action-oriented skills training groups, and 47 families were randomly assigned to unstructured EDM support…

  20. Specific in planta recognition of two GKLR proteins of the downy mildew Bremia lactucae revealed in a large effector screen in lettuce.

    PubMed

    Stassen, Joost H M; den Boer, Erik; Vergeer, Pim W J; Andel, Annemiek; Ellendorff, Ursula; Pelgrom, Koen; Pel, Mathieu; Schut, Johan; Zonneveld, Olaf; Jeuken, Marieke J W; Van den Ackerveken, Guido

    2013-11-01

    Breeding lettuce (Lactuca sativa) for resistance to the downy mildew pathogen Bremia lactucae is mainly achieved by introgression of dominant downy mildew resistance (Dm) genes. New Bremia races quickly render Dm genes ineffective, possibly by mutation of recognized host-translocated effectors or by suppression of effector-triggered immunity. We have previously identified 34 potential RXLR(-like) effector proteins of B. lactucae that were here tested for specific recognition within a collection of 129 B. lactucae-resistant Lactuca lines. Two effectors triggered a hypersensitive response: BLG01 in 52 lines, predominantly L. saligna, and BLG03 in two L. sativa lines containing Dm2 resistance. The N-terminal sequences of BLG01 and BLG03, containing the signal peptide and GKLR variant of the RXLR translocation motif, are not required for in planta recognition but function in effector delivery. The locus responsible for BLG01 recognition maps to the bottom of lettuce chromosome 9, whereas recognition of BLG03 maps in the RGC2 cluster on chromosome 2. Lactuca lines that recognize the BLG effectors are not resistant to Bremia isolate Bl:24 that expresses both BLG genes, suggesting that Bl:24 can suppress the triggered immune responses. In contrast, lettuce segregants displaying Dm2-mediated resistance to Bremia isolate Bl:5 are responsive to BLG03, suggesting that BLG03 is a candidate Avr2 protein. PMID:23883357

  1. In Planta Biocontrol of Pectobacterium atrosepticum by Rhodococcus erythropolis Involves Silencing of Pathogen Communication by the Rhodococcal Gamma-Lactone Catabolic Pathway

    PubMed Central

    Barbey, Corinne; Crépin, Alexandre; Bergeau, Dorian; Ouchiha, Asma; Mijouin, Lily; Taupin, Laure; Orange, Nicole; Feuilloley, Marc; Dufour, Alain; Burini, Jean-François; Latour, Xavier

    2013-01-01

    The virulence of numerous Gram-negative bacteria is under the control of a quorum sensing process based on synthesis and perception of N-acyl homoserine lactones. Rhodococcus erythropolis, a Gram-positive bacterium, has recently been proposed as a biocontrol agent for plant protection against soft-rot bacteria, including Pectobacterium. Here, we show that the γ-lactone catabolic pathway of R. erythropolis disrupts Pectobacterium communication and prevents plant soft-rot. We report the first characterization and demonstration of N-acyl homoserine lactone quenching in planta. In particular, we describe the transcription of the R. erythropolis lactonase gene, encoding the key enzyme of this pathway, and the subsequent lactone breakdown. The role of this catabolic pathway in biocontrol activity was confirmed by deletion of the lactonase gene from R. erythropolis and also its heterologous expression in Escherichia coli. The γ-lactone catabolic pathway is induced by pathogen communication rather than by pathogen invasion. This is thus a novel and unusual biocontrol pathway, differing from those previously described as protecting plants from phytopathogens. These findings also suggest the existence of an additional pathway contributing to plant protection. PMID:23805254

  2. In Planta Biocontrol of Pectobacterium atrosepticum by Rhodococcus erythropolis Involves Silencing of Pathogen Communication by the Rhodococcal Gamma-Lactone Catabolic Pathway.

    PubMed

    Barbey, Corinne; Crépin, Alexandre; Bergeau, Dorian; Ouchiha, Asma; Mijouin, Lily; Taupin, Laure; Orange, Nicole; Feuilloley, Marc; Dufour, Alain; Burini, Jean-François; Latour, Xavier

    2013-01-01

    The virulence of numerous Gram-negative bacteria is under the control of a quorum sensing process based on synthesis and perception of N-acyl homoserine lactones. Rhodococcus erythropolis, a Gram-positive bacterium, has recently been proposed as a biocontrol agent for plant protection against soft-rot bacteria, including Pectobacterium. Here, we show that the γ-lactone catabolic pathway of R. erythropolis disrupts Pectobacterium communication and prevents plant soft-rot. We report the first characterization and demonstration of N-acyl homoserine lactone quenching in planta. In particular, we describe the transcription of the R. erythropolis lactonase gene, encoding the key enzyme of this pathway, and the subsequent lactone breakdown. The role of this catabolic pathway in biocontrol activity was confirmed by deletion of the lactonase gene from R. erythropolis and also its heterologous expression in Escherichia coli. The γ-lactone catabolic pathway is induced by pathogen communication rather than by pathogen invasion. This is thus a novel and unusual biocontrol pathway, differing from those previously described as protecting plants from phytopathogens. These findings also suggest the existence of an additional pathway contributing to plant protection. PMID:23805254

  3. Colonization process of olive tissues by Verticillium dahliae and its in planta interaction with the biocontrol root endophyte Pseudomonas fluorescens PICF7

    PubMed Central

    Prieto, Pilar; Navarro‐Raya, Carmen; Valverde‐Corredor, Antonio; Amyotte, Stefan G.; Dobinson, Katherine F.; Mercado‐Blanco, Jesús

    2009-01-01

    Summary The colonization process of Olea europaea by the defoliating pathotype of Verticillium dahliae, and the in planta interaction with the endophytic, biocontrol strain Pseudomonas fluorescens PICF7 were determined. Differential fluorescent protein tagging was used for the simultaneous visualization of P. fluorescens PICF7 and V. dahliae in olive tissues. Olive plants were bacterized with PICF7 and then transferred to V. dahliae‐infested soil. Monitoring olive colonization events by V. dahliae and its interaction with PICF7 was conducted using a non‐gnotobiotic system, confocal laser scanner microscopy and tissue vibratoming sections. A yellow fluorescently tagged V. dahliae derivative (VDAT‐36I) was obtained by Agrobacterium tumefaciens‐mediated transformation. Isolate VDAT‐36I quickly colonized olive root surface, successfully invaded root cortex and vascular tissues via macro‐ and micro‐breakages, and progressed to the aerial parts of the plant through xylem vessel cells. Strain PICF7 used root hairs as preferred penetration site, and once established on/in root tissues, hindered pathogen colonization. For the first time using this approach, the entire colonization process of a woody plant by V. dahliae is reported. Early and localized root surface and root endophytic colonization by P. fluorescens PICF7 is needed to impair full progress of verticillium wilt epidemics in olive. PMID:21255281

  4. In Planta Stage-Specific Fungal Gene Profiling Elucidates the Molecular Strategies of Fusarium graminearum Growing inside Wheat Coleoptiles[W][OA

    PubMed Central

    Zhang, Xiao-Wei; Jia, Lei-Jie; Zhang, Yan; Jiang, Gang; Li, Xuan; Zhang, Dong; Tang, Wei-Hua

    2012-01-01

    The ascomycete Fusarium graminearum is a destructive fungal pathogen of wheat (Triticum aestivum). To better understand how this pathogen proliferates within the host plant, we tracked pathogen growth inside wheat coleoptiles and then examined pathogen gene expression inside wheat coleoptiles at 16, 40, and 64 h after inoculation (HAI) using laser capture microdissection and microarray analysis. We identified 344 genes that were preferentially expressed during invasive growth in planta. Gene expression profiles for 134 putative plant cell wall–degrading enzyme genes suggest that there was limited cell wall degradation at 16 HAI and extensive degradation at 64 HAI. Expression profiles for genes encoding reactive oxygen species (ROS)–related enzymes suggest that F. graminearum primarily scavenges extracellular ROS before a later burst of extracellular ROS is produced by F. graminearum enzymes. Expression patterns of genes involved in primary metabolic pathways suggest that F. graminearum relies on the glyoxylate cycle at an early stage of plant infection. A secondary metabolite biosynthesis gene cluster was specifically induced at 64 HAI and was required for virulence. Our results indicate that F. graminearum initiates infection of coleoptiles using covert penetration strategies and switches to overt cellular destruction of tissues at an advanced stage of infection. PMID:23266949

  5. A ubiquitin carboxyl extension protein secreted from a plant-parasitic nematode Globodera rostochiensis is cleaved in planta to promote plant parasitism.

    PubMed

    Chronis, Demosthenis; Chen, Shiyan; Lu, Shunwen; Hewezi, Tarek; Carpenter, Sara C D; Loria, Rosemary; Baum, Thomas J; Wang, Xiaohong

    2013-04-01

    Nematode effector proteins originating from esophageal gland cells play central roles in suppressing plant defenses and in formation of the plant feeding cells that are required for growth and development of cyst nematodes. A gene (GrUBCEP12) encoding a unique ubiquitin carboxyl extension protein (UBCEP) that consists of a signal peptide for secretion, a mono-ubiquitin domain, and a 12 amino acid carboxyl extension protein (CEP12) domain was cloned from the potato cyst nematode Globodera rostochiensis. This GrUBCEP12 gene was expressed exclusively within the nematode's dorsal esophageal gland cell, and was up-regulated in the parasitic second-stage juvenile, correlating with the time when feeding cell formation is initiated. We showed that specific GrUBCEP12 knockdown via RNA interference reduced nematode parasitic success, and that over-expression of the secreted Gr(Δ) (SP) UBCEP12 protein in potato resulted in increased nematode susceptibility, providing direct evidence that this secreted effector is involved in plant parasitism. Using transient expression assays in Nicotiana benthamiana, we found that Gr(Δ) (SP) UBCEP12 is processed into free ubiquitin and a CEP12 peptide (GrCEP12) in planta, and that GrCEP12 suppresses resistance gene-mediated cell death. A target search showed that expression of RPN2a, a gene encoding a subunit of the 26S proteasome, was dramatically suppressed in Gr(Δ) (SP) UBCEP12 but not GrCEP12 over-expression plants when compared with control plants. Together, these results suggest that, when delivered into host plant cells, Gr(Δ) (SP) UBCEP12 becomes two functional units, one acting to suppress plant immunity and the other potentially affecting the host 26S proteasome, to promote feeding cell formation. PMID:23346875

  6. Virulence and in planta movement of Xanthomonas hortorum pv. pelargonii are affected by the diffusible signal factor (DSF)-dependent quorum sensing system.

    PubMed

    Barel, Victoria; Chalupowicz, Laura; Barash, Isaac; Sharabani, Galit; Reuven, Michal; Dror, Orit; Burdman, Saul; Manulis-Sasson, Shulamit

    2015-09-01

    Xanthomonas hortorum pv. pelargonii (Xhp), the causal agent of bacterial blight in pelargonium, is the most threatening bacterial disease of this ornamental worldwide. To gain an insight into the regulation of virulence in Xhp, we have disrupted the quorum sensing (QS) genes, which mediate the biosynthesis and sensing of the diffusible signal factor (DSF). Mutations in rpfF (encoding the DSF synthase) and rpfC (encoding the histidine sensor kinase of the two-component system RfpC/RpfG) and overexpression of rpfF showed a significant reduction in incidence and severity of the disease on pelargonium. Confocal laser scanning microscopy images of inoculated plants with a green fluorescent protein (GFP)-labelled wild-type strain showed that the pathogen is homogeneously dispersed in the lumen of xylem vessels, reaching the apex and invading the intercellular spaces of the leaf mesophyll tissue within 21 days. In contrast, the rpfF and rpfC knockout mutants, as well as the rpfF-overexpressing strain, remained confined to the vicinity of the inoculation site. The rpfF and rpfC mutants formed large incoherent aggregates in the xylem vessels that might interfere with upward movement of the bacterium within the plant. Both mutants also formed extended aggregates under in vitro conditions, whereas the wild-type strain formed microcolonies. Expression levels of putative virulence genes in planta were substantially reduced within 48 h after inoculation with the QS mutants when compared with the wild-type. The results presented indicate that an optimal DSF concentration is crucial for successful colonization and virulence of Xhp in pelargonium. PMID:25530086

  7. RiPEIP1, a gene from the arbuscular mycorrhizal fungus Rhizophagus irregularis, is preferentially expressed in planta and may be involved in root colonization.

    PubMed

    Fiorilli, Valentina; Belmondo, Simone; Khouja, Hassine Radhouane; Abbà, Simona; Faccio, Antonella; Daghino, Stefania; Lanfranco, Luisa

    2016-08-01

    Transcriptomics and genomics data recently obtained from the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis have offered new opportunities to decipher the contribution of the fungal partner to the establishment of the symbiotic association. The large number of genes which do not show similarity to known proteins witnesses the uniqueness of this group of plant-associated fungi. In this work, we characterize a gene that was called RiPEIP1 (Preferentially Expressed In Planta). Its expression is strongly induced in the intraradical phase, including arbuscules, and follows the expression profile of the Medicago truncatula phosphate transporter MtPT4, a molecular marker of a functional symbiosis. Indeed, mtpt4 mutant plants, which exhibit low mycorrhizal colonization and an accelerated arbuscule turnover, also show a reduced RiPEIP1 mRNA abundance. To further characterize RiPEIP1, in the absence of genetic transformation protocols for AM fungi, we took advantage of two different fungal heterologous systems. When expressed as a GFP fusion in yeast cells, RiPEIP1 localizes in the endomembrane system, in particular to the endoplasmic reticulum, which is consistent with the in silico prediction of four transmembrane domains. We then generated RiPEIP1-expressing strains of the fungus Oidiodendron maius, ericoid endomycorrhizal fungus for which transformation protocols are available. Roots of Vaccinium myrtillus colonized by RiPEIP1-expressing transgenic strains showed a higher mycorrhization level compared to roots colonized by the O. maius wild-type strain, suggesting that RiPEIP1 may regulate the root colonization process. PMID:27075897

  8. In planta assessment of the role of thioredoxin h proteins in the regulation of S-locus receptor kinase signaling in transgenic Arabidopsis.

    PubMed

    Yamamoto, Masaya; Nasrallah, June B

    2013-11-01

    The self-incompatibility (SI) response of the Brassicaceae is mediated by allele-specific interaction between the stigma-localized S-locus receptor kinase (SRK) and its ligand, the pollen coat-localized S-locus cysteine-rich protein (SCR). Based on work in Brassica spp., the thioredoxin h-like proteins THL1 and THL2, which interact with SRK, have been proposed to function as oxidoreductases that negatively regulate SRK catalytic activity. By preventing the spontaneous activation of SRK in the absence of SCR ligand, these thioredoxins are thought to be essential for the success of cross pollinations in self-incompatible plants. However, the in planta role of thioredoxins in the regulation of SI signaling has not been conclusively demonstrated. Here, we addressed this issue using Arabidopsis thaliana plants transformed with the SRKb-SCRb gene pair isolated from self-incompatible Arabidopsis lyrata. These plants express an intense SI response, allowing us to exploit the extensive tools and resources available in A. thaliana for analysis of SI signaling. To test the hypothesis that SRK is redox regulated by thioredoxin h, we expressed a mutant form of SRKb lacking a transmembrane-localized cysteine residue thought to be essential for the SRK-thioredoxin h interaction. We also analyzed transfer DNA insertion mutants in the A. thaliana orthologs of THL1 and THL2. In neither case did we observe an effect on the pollination responses of SRKb-expressing stigmas toward incompatible or compatible pollen. Our results are consistent with the conclusion that, contrary to their proposed role, thioredoxin h proteins are not required to prevent the spontaneous activation of SRK in the A. thaliana stigma. PMID:24077073

  9. Endogenous silencing of Puccinia triticina pathogenicity genes through in planta-expressed sequences leads to the suppression of rust diseases on wheat.

    PubMed

    Panwar, Vinay; McCallum, Brent; Bakkeren, Guus

    2013-02-01

    Rust fungi are destructive plant pathogens. The draft genomes of several wheat-infecting species have been released and potential pathogenicity genes identified through comparative analyses to fungal pathogens that are amenable to genetic manipulation. Functional gene analysis tools are needed to understand the infection process of these obligate parasites and to confirm whether predicted pathogenicity genes could become targets for disease control. We have modified an Agrobacterium tumefaciens-mediated in planta-induced transient gene silencing (PITGS) assay for use in Triticum spp. (wheat), and used this assay to target predicted wheat leaf rust fungus, Puccinia triticina (Pt) pathogenicity genes, a MAP kinase (PtMAPK1), a cyclophilin (PtCYC1) and calcineurin B (PtCNB), to analyze their roles in disease. Agroinfiltration effectively delivered hairpin silencing constructs in wheat, leading to the generation of fungal gene-specific siRNA molecules in infiltrated leaves, and resulting in up to 70% reduction in transcription of the endogenous target genes in superinfected Pt. In vivo silencing caused severe disease suppression, compromising fungal growth and sporulation, as viewed by confocal microscopy and measured by reductions in fungal biomass and emergence of uredinia. Interestingly, using the same gene constructs, suppression of infection by Puccinia graminis and Puccinia striiformis was also achieved. Our results show that A. tumefaciens-mediated PITGS can be used as a reverse-genetics tool to discover gene function in rust fungi. This proof-of-concept study indicates that the targeted fungal transcripts might be important in pathogenesis, and could potentially be used as promising targets for developing RNA interference-based resistance against rust fungi. PMID:23110316

  10. Boosting in planta production of antigens derived from the porcine reproductive and respiratory syndrome virus (PRRSV) and subsequent evaluation of their immunogenicity.

    PubMed

    Piron, Robin; De Koker, Stefaan; De Paepe, Annelies; Goossens, Julie; Grooten, Johan; Nauwynck, Hans; Depicker, Ann

    2014-01-01

    Porcine reproductive and respiratory syndrome (PRRS) is a disease of swine, caused by an arterivirus, the PRRS virus (PRRSV). This virus infects pigs worldwide and causes huge economic losses. Due to genetic drift, current vaccines are losing their power. Adaptable vaccines could provide a solution to this problem. This study aims at producing in planta a set of antigens derived from the PRRSV glycoproteins (GPs) to be included in a subunit vaccine. We selected the GP3, GP4 and GP5 and optimized these for production in an Arabidopsis seed platform by removing transmembrane domains (Tm) and/or adding stabilizing protein domains, such as the green fluorescent protein (GFP) and immunoglobulin (IgG) 'Fragment crystallizable' (Fc) chains. Accumulation of the GPs with and without Tm was low, reaching no more than 0.10% of total soluble protein (TSP) in homozygous seed. However, addition of stabilizing domains boosted accumulation up to a maximum of 2.74% of TSP when GFP was used, and albeit less effectively, also the Fc chains of the porcine IgG3 and murine IgG2a increased antigen accumulation, to 0.96% and 1.81% of TSP respectively, while the murine IgG3 Fc chain did not. Antigens with Tm were less susceptible to these manipulations to increase yield. All antigens were produced in the endoplasmic reticulum and accordingly, they carried high-mannose N-glycans. The immunogenicity of several of those antigens was assessed and we show that vaccination with purified antigens did elicit the production of antibodies with virus neutralizing activity in mice but not in pigs. PMID:24614617

  11. Boosting In Planta Production of Antigens Derived from the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and Subsequent Evaluation of Their Immunogenicity

    PubMed Central

    Piron, Robin; De Koker, Stefaan; De Paepe, Annelies; Goossens, Julie; Grooten, Johan; Nauwynck, Hans; Depicker, Ann

    2014-01-01

    Porcine reproductive and respiratory syndrome (PRRS) is a disease of swine, caused by an arterivirus, the PRRS virus (PRRSV). This virus infects pigs worldwide and causes huge economic losses. Due to genetic drift, current vaccines are losing their power. Adaptable vaccines could provide a solution to this problem. This study aims at producing in planta a set of antigens derived from the PRRSV glycoproteins (GPs) to be included in a subunit vaccine. We selected the GP3, GP4 and GP5 and optimized these for production in an Arabidopsis seed platform by removing transmembrane domains (Tm) and/or adding stabilizing protein domains, such as the green fluorescent protein (GFP) and immunoglobulin (IgG) ‘Fragment crystallizable’ (Fc) chains. Accumulation of the GPs with and without Tm was low, reaching no more than 0.10% of total soluble protein (TSP) in homozygous seed. However, addition of stabilizing domains boosted accumulation up to a maximum of 2.74% of TSP when GFP was used, and albeit less effectively, also the Fc chains of the porcine IgG3 and murine IgG2a increased antigen accumulation, to 0.96% and 1.81% of TSP respectively, while the murine IgG3 Fc chain did not. Antigens with Tm were less susceptible to these manipulations to increase yield. All antigens were produced in the endoplasmic reticulum and accordingly, they carried high-mannose N-glycans. The immunogenicity of several of those antigens was assessed and we show that vaccination with purified antigens did elicit the production of antibodies with virus neutralizing activity in mice but not in pigs. PMID:24614617

  12. ESTIGMA Y VIH/SIDA ENTRE PADRES/MADRES Y ADOLESCENTES PUERTORRIQUEÑOS/AS

    PubMed Central

    Pérez, Grace Rosado; Reyes, Glendalys Rivera; Villanueva, Victoria Larrieux; Torres, Gilliam J. Torres; Díaz, Elba Betancourt; Varas-Díaz, Nelson; Villaruel, Antonia

    2016-01-01

    La comunicación entre padres/madres y adolescentes sobre el tema de la sexualidad es importante para el desarrollo de la salud de personas jóvenes. Dicha comunicación puede verse negativamente impactada por actitudes estigmatizantes hacia el tema del VIH/SIDA. El objetivo de este estudio fue identificar actitudes estigmatizantes hacia el VIH/SIDA entre padres/madres y adolescentes puertorriqueños/as. Este esfuerzo es parte del Proyecto Cuídalos, dirigido a probar una intervención en formato electrónico que busca aumentar la comunicación sobre sexualidad y salud entre padres/madres y adolescentes mediante un diseño experimental con 458 diadas de padres/madres y adolescentes de 13 a 17 años. Para propósitos de este artículo reportamos estadísticas descriptivas sobre estigma hacia el VIH/SIDA con la información recopilada en la medición basal. Tanto adultos/as como adolescentes mostraron actitudes estigmatizantes hacia el VIH/SIDA. A la luz de los resultados es necesario continuar desarrollando intervenciones para la reducción de estigma en esta población. Los/as padres/madres pueden ser un recurso invaluable para reducir el estigma en los/as jóvenes, y prevenir conductas sexuales de riesgo e infecciones. PMID:27099649

  13. Tdp studies and tests for C. A. Energia Electrica de Venezuela (enelven) at planta ramon laguna, units RL-17 and RL-10. Volume 2. Unit RL-10 boiler condition assessment report. Export trade information

    SciTech Connect

    Not Available

    1991-03-28

    The study, conducted by Babcock and Wilcox, was funded by the U.S. Trade and Development agency on behalf of Enelven. In order to maximize generated power output and minimize operating costs at Planta Ramon Laguna, tests were done to evaluate the condition of equipment at the plant. In order to identify any damage and determine the operating output of each unit, assessments were done of the furnaces, boilers, generators and boiler feed pumps being used in the plant. The report presents the results of these tests. This is the second of three volumes and it includes the following section: (1) Condition Assessment of Unit RL-10 Boiler.

  14. Differential subcellular targeting of recombinant human α₁-proteinase inhibitor influences yield, biological activity and in planta stability of the protein in transgenic tomato plants.

    PubMed

    Jha, Shweta; Agarwal, Saurabh; Sanyal, Indraneel; Jain, G K; Amla, D V

    2012-11-01

    The response of protein accumulation site on yield, biological activity and in planta stability of therapeutic recombinant human proteinase inhibitor (α₁-PI) was analyzed via targeting to different subcellular locations, like endoplasmic reticulum (ER), apoplast, vacuole and cytosol in leaves of transgenic tomato plants. In situ localization of the recombinant α₁-PI protein in transgenic plant cells was monitored by immunohistochemical staining. Maximum accumulation of recombinant α₁-PI in T₀ and T₁ transgenic tomato plants was achieved from 1.5 to 3.2% of total soluble protein (TSP) by retention in ER lumen, followed by vacuole and apoplast, whereas cytosolic targeting resulted into degradation of the protein. The plant-derived recombinant α₁-PI showed biological activity for elastase inhibition, as monitored by residual porcine pancreatic elastase (PPE) activity assay and band-shift assay. Recombinant α₁-PI was purified from transgenic tomato plants with high yield, homogeneity and biological activity. Purified protein appeared as a single band of ∼48-50 kDa on SDS-PAGE with pI value ranging between 5.1 and 5.3. Results of mass spectrometry and optical spectroscopy of purified recombinant α₁-PI revealed the structural integrity of the recombinant protein comparable to native serum α₁-PI. Enzymatic deglycosylation and lectin-binding assays with the purified recombinant α₁-PI showed compartment-specific N-glycosylation of the protein targeted to ER, apoplast and vacuole. Conformational studies based on urea-induced denaturation and circular dichroism (CD) spectroscopy revealed relatively lower stability of the recombinant α₁-PI protein, compared to its serum counterpart. Pharmacokinetic evaluation of plant derived recombinant and human plasma-purified α₁-PI in rat, by intravenous route, revealed significantly faster plasma clearance and lower area under curve (AUC) of recombinant protein. Our data suggested significance of

  15. Estudo comparativo entre estrelas centrais de nebulosas planetárias deficientes em hidrogênio

    NASA Astrophysics Data System (ADS)

    Marcolino, W. L. F.; de Araújo, F. X.

    2003-08-01

    Apresentamos neste trabalho o resultado de um estudo das principais características espectrais das estrelas centrais de nebulosas planetárias (ECNP) deficientes em hidrogênio. A origem e a evolução dessas estrelas ainda constitui um problema em aberto na evolução estelar. Geralmente esses objetos são divididos em [WCE], [WCL] e [WELS]. Os tipos [WCE] e [WCL] apresentam um espectro típico de uma estrela Wolf-Rayet carbonada de população I e as [WELS] apresentam linhas fracas de carbono e oxigênio em emissão. Existem evidências que apontam a seguinte sequência evolutiva : [WCL] = > [WCE] = > [WELS] = > PG 1159 (pré anã-branca). No entanto, tal cenário apresenta falhas como por exemplo a falta de ECNP entre os tipos [WCL] e [WCE]. Baseados em uma amostra de 24 objetos obtida no telescópio de 1.52m em La Silla, Chile (acordo ESO/ON), ao longo do ano 2000, apresentamos os resultados da comparação das larguras equivalentes de diversas linhas relevantes entre os tipos [WCL], [WCE] e [WELS]. Verificamos que nossos dados estão de acordo com a sequência evolutiva. Baseado nas linhas de C IV, conseguimos dividir pela primeira vez as [WELS] em dois grupos principais. Além disso, os dados reforçam a afirmação de que as [WCE] são as estrelas que possuem a maior temperatura entre as ECNP deficientes em hidrogênio. Discutimos ainda, a escassez de dados disponíveis na literatura e a necessidade da obtenção de parametros físicos para estes objetos.

  16. Genomic homologous recombination in planta.

    PubMed Central

    Gal, S; Pisan, B; Hohn, T; Grimsley, N; Hohn, B

    1991-01-01

    A system for monitoring intrachromosomal homologous recombination in whole plants is described. A multimer of cauliflower mosaic virus (CaMV) sequences, arranged such that CaMV could only be produced by recombination, was integrated into Brassica napus nuclear DNA. This set-up allowed scoring of recombination events by the appearance of viral symptoms. The repeated homologous regions were derived from two different strains of CaMV so that different recombinant viruses (i.e. different recombination events) could be distinguished. In most of the transgenic plants, a single major virus species was detected. About half of the transgenic plants contained viruses of the same type, suggesting a hotspot for recombination. The remainder of the plants contained viruses with cross-over sites distributed throughout the rest of the homologous sequence. Sequence analysis of two recombinant molecules suggest that mismatch repair is linked to the recombination process. Images PMID:2026150

  17. Etude des relations entre photosynthese respiration, transpiration et nutrition minerale chez le ble

    NASA Astrophysics Data System (ADS)

    André, M.; Ducloux, H.; Richaud, C.; Massimino, D.; Daguenet, A.; Massimino, J.; Gerbaud, A.

    La croissance du Blé Triticum aestivum a été étudiée en environnement contrôlé et fermé pendant une période de 70 jours. Les échanges gazeux (Photosynthèse, Respiration) hydriques (Transpiration) et la consommation en éléments minéraux (Azote, Phosphore, Potassium) ont été mesurés en continu. On présentera les relations dynamiques observées entre les différentes fonctions physiologiques, d'une part sous l'influence de la croissance et d'autre part en réponse à des modifications de l'environnement. L'influence de la teneur en CO2 pendant la croissance (teneur normale ou doublée) sera mise en évidence.

  18. No Financial Disincentive for Choosing More Healthful Entrées on Children’s Menus in Full-Service Restaurants

    PubMed Central

    West, Delia

    2013-01-01

    Children are eating restaurant foods more than ever before, and price is among the top considerations for food choices. We categorized and enumerated entrées on children’s menus from 75 full-service restaurant chains to compare prices of more healthful and less healthful entrées to test the assumption that more healthful food is more expensive. The mean (standard deviation) price of more healthful entrées ($5.38 [$2.01]) was not significantly different from the price of less healthful entrées ($5.27 [$2.04]). In contrast to research demonstrating that more healthful foods tend to be more expensive in grocery stores, more healthful entrées on children’s menus in restaurants were not more expensive than less healthful entrées. PMID:23742942

  19. An Environmental Management Model of Thermal Waters in Entre Ríos Province, Argentina

    NASA Astrophysics Data System (ADS)

    Pablo, Mársico Daniel; Luís, Díaz Eduardo; Ivana, Zecca; Oscar, Dallacosta; Antonio, Paz-González

    2015-04-01

    Deep exploratory drillings, i.e. those with more than 500 meters depth, have been performed in the Entre Ríos province, Argentina, in order to ascertain the presence of thermal water. Drilling began in 1994, and until now there have been 18 polls with very variable results in terms of mineralization, resource flow, and temperature. The aim of this study was to present a management model, which should allow operators of thermal complexes to further develop procedures for safeguarding the biodiversity of the ecosystems involved, both during exploration and exploitation activities. The environmental management Plan proposed is constituted by a set of technical procedures that are formulated and should be performed during the stages of exploration and exploitation of the resource, and consists of: environmental monitoring, environmental audit, public information and contingency programs. This Plan describes the measures and proposals aimed at protecting environmental quality in the area of influence of a thermal complex project, ensuring that its execution remains environmentally responsibly, and allowing implementation of specific actions to prevent or correct environmental impacts, as predicted in the evaluation of the Environmental Program. The audit of environmental impact includes and takes into account natural factors, such as water, soil, atmosphere, flora and fauna, and also cultural factors. The technical audit Plan was prepared in order to get a systematic structure and organization of the verification process, and also with regard to document the degree of implementation of the proposed mitigation measures. Finally, an environmental contingency program was implemented, and its objective was to consider the safeguarding of life and its natural environment. Thus, a guide has been developed with the main actions to be taken on a contingency, since forecast increases the efficiency of the response. The methodology developed here was adopted as the procedure

  20. Tdp studies and tests for C. A. Energia Electrica de Venezuela (enelven) at planta ramon laguna, units RL-17 and RL-10. Volume 1. Executive summary, RL-17 test report, and gas conversion proposals. Export trade information

    SciTech Connect

    Not Available

    1991-03-28

    The study, conducted by Babcock and Wilcox, was funded by the U.S. Trade and Development agency on behalf of Enelven. In order to maximize generated power output and minimize operating costs at Planta Ramon Laguna, tests were done to evaluate the condition of equipment at the plant. In order to identify any damage and determine the operating output of each unit, assessments were done of the furnaces, boilers, generators and boiler feed pumps being used in the plant. The report presents the results of these tests. This is the first of three volumes and it is divided into the following sections: (1) Executive Summary; (2) Hydrogen Damage Assessment; (3) RL-17 Gas Conversion Proposal; (4) RL-10 and RL-11 Gas Conversion Proposals.

  1. Religiosidade, juventude e sexualidade: entre a autonomia e a rigidez1

    PubMed Central

    Silva, Cristiane Gonçalves da; Santos, Alessandro Oliveira; Licciardi, Daniele Carli; Paiva, Vera; Parker, Richard

    2009-01-01

    Esse artigo descreve como jovens religiosos e autoridades religiosas de sua comunidade compreendem a sexualidade, considerando suas experiências pessoais e como membros de comunidades religiosas. A análise pretende contribuir para que políticas públicas dedicadas à promoção da saúde sexual da juventude considerem a religiosidade, no contexto de um estado laico e da promoção do direito à prevenção. Foram realizadas 26 entrevistas abertas e semidirigidas em diferentes comunidades da região metropolitana da cidade de São Paulo (comunidades católicas, da umbanda, do candomblé e de diferentes denominações evangélicas) sobre iniciação sexual, casamento, gravidez, contracepção e prevenção das DST/Aids, homossexualidade, aborto e direitos humanos. Observou-se como jovens e autoridades religiosas convivem com a tensão entre tradição e modernidade e os distintos discursos sobre a sexualidade. Como sujeitos religiosos (do discurso religioso) e sujeitos sexuais (de discursos sobre sexualidade), devem ser incorporados pelos programas como sujeitos de direito nos termos de sua religiosidade. PMID:21886456

  2. Occurrence of alternariol and alternariol monomethyl ether in beverages from the Entre Rios Province market, Argentina.

    PubMed

    Broggi, Leticia; Reynoso, Cora; Resnik, Silvia; Martinez, Fernanda; Drunday, Vanesa; Bernal, Angela Romero

    2013-02-01

    One hundred and eighty five samples of red, white and rosé wines and different juices purchased in Entre Rios, Argentina, were analyzed for the Alternaria mycotoxins alternariol (AOH) and alternariol methyl ether (AME). White wines were analyzed after removal of alcohol by a nitrogen stream and concentrated. AOH in red wines was cleaned up by solid-phase extraction columns in series (octadecyl and amino propyl modified silica) and AME quantified directly on the sample. The juices were filtered and concentrated, and then all sample extracts were quantified by high performance liquid chromatography with photodiode array detector that allows confirmation through UV spectra. Method validation revealed a good sensitivity with adequate LOD and LOQ for AME and less sensitivity for AOH (i.e. white wine: AME 0.8 and 1.4 ng/mL, AOH 2 and 3.3 ng/mL; red wine: AME 0.1 and 0.2 ng/mL, AOH 4.5 and 7.5 ng/mL; apple juice: AME 1.7 and 2.8 ng/mL, AOH 5 and 9 ng/mL; other juices: AME 2.0 and 3.1 ng/mL, AOH 6 and 10 ng/mL). Recoveries in all cases were greater than 80 %. Four of 53 white wine samples were contaminated with AOH with a maximum level of 18 ng/mL, 6 of 56 samples of red wine had a maximum of 13 ng/mL, and 3 of 68 samples of juices had traces of AOH. AME was less frequently detected than AOH, and the LOD and LOQ for AME are smaller than for AOH. Only three samples of white wine and one of red wine were contaminated, but in only one white wine sample (AME 225 ng/mL) did the toxin level exceed the LOQ. PMID:23334721

  3. Analyse des interactions energetiques entre un arena et son systeme de refrigeration

    NASA Astrophysics Data System (ADS)

    Seghouani, Lotfi

    La presente these s'inscrit dans le cadre d'un projet strategique sur les arenas finance par le CRSNG (Conseil de Recherche en Sciences Naturelles et en Genie du Canada) qui a pour but principal le developpement d'un outil numerique capable d'estimer et d'optimiser la consommation d'energie dans les arenas et curlings. Notre travail s'inscrit comme une suite a un travail deja realise par DAOUD et coll. (2006, 2007) qui a developpe un modele 3D (AIM) en regime transitoire de l'arena Camilien Houde a Montreal et qui calcule les flux de chaleur a travers l'enveloppe du batiment ainsi que les distributions de temperatures et d'humidite durant une annee meteorologique typique. En particulier, il calcule les flux de chaleur a travers la couche de glace dus a la convection, la radiation et la condensation. Dans un premier temps nous avons developpe un modele de la structure sous la glace (BIM) qui tient compte de sa geometrie 3D, des differentes couches, de l'effet transitoire, des gains de chaleur du sol en dessous et autour de l'arena etudie ainsi que de la temperature d'entree de la saumure dans la dalle de beton. Par la suite le BIM a ete couple le AIM. Dans la deuxieme etape, nous avons developpe un modele du systeme de refrigeration (REFSYS) en regime quasi-permanent pour l'arena etudie sur la base d'une combinaison de relations thermodynamiques, de correlations de transfert de chaleur et de relations elaborees a partir de donnees disponibles dans le catalogue du manufacturier. Enfin le couplage final entre l'AIM +BIM et le REFSYS a ete effectue sous l'interface du logiciel TRNSYS. Plusieurs etudes parametriques on ete entreprises pour evaluer les effets du climat, de la temperature de la saumure, de l'epaisseur de la glace, etc. sur la consommation energetique de l'arena. Aussi, quelques strategies pour diminuer cette consommation ont ete etudiees. Le considerable potentiel de recuperation de chaleur au niveau des condenseurs qui peut reduire l'energie requise par

  4. An updated model for nitrate uptake modelling in plants. I. Functional component: cross-combination of flow–force interpretation of nitrate uptake isotherms, and environmental and in planta regulation of nitrate influx

    PubMed Central

    Le Deunff, Erwan; Malagoli, Philippe

    2014-01-01

    Background and Aims In spite of major breakthroughs in the last three decades in the identification of root nitrate uptake transporters in plants and the associated regulation of nitrate transport activities, a simplified and operational modelling approach for nitrate uptake is still lacking. This is due mainly to the difficulty in linking the various regulations of nitrate transport that act at different levels of time and on different spatial scales. Methods A cross-combination of a Flow–Force approach applied to nitrate influx isotherms and experimentally determined environmental and in planta regulation is used to model nitrate in oilseed rape, Brassica napus. In contrast to ‘Enzyme–Substrate’ interpretations, a Flow–Force modelling approach considers the root as a single catalytic structure and does not infer hypothetical cellular processes among nitrate transporter activities across cellular layers in the mature roots. In addition, this approach accounts for the driving force on ion transport based on the gradient of electrochemical potential, which is more appropriate from a thermodynamic viewpoint. Key Results and Conclusions Use of a Flow–Force formalism on nitrate influx isotherms leads to the development of a new conceptual mechanistic basis to model more accurately N uptake by a winter oilseed rape crop under field conditions during the whole growth cycle. This forms the functional component of a proposed new structure–function mechanistic model of N uptake. PMID:24638820

  5. In Planta Mutagenesis of Src Homology 3 Domain-like Fold of NdhS, a Ferredoxin-binding Subunit of the Chloroplast NADH Dehydrogenase-like Complex in Arabidopsis

    PubMed Central

    Yamamoto, Hiroshi; Shikanai, Toshiharu

    2013-01-01

    Chloroplast NADH dehydrogenase-like (NDH) complex mediates cyclic electron transport around photosystem I and chlororespiration in angiosperms. The Src homology 3 domain (SH3)-like fold protein NdhS/CRR31 is an NDH subunit that is necessary for high affinity binding of ferredoxin, indicating that chloroplast NDH functions as a ferredoxin:plastoquinone oxidoreductase. However, the mechanism of the interaction between NdhS and ferredoxin is unclear. In this study, we analyzed their interaction in planta by using site-directed mutagenesis of NdhS. In general, binding of ferredoxin to its target proteins depends on electrostatic interaction. In silico analysis predicted the presence of a positively charged pocket in the SH3-like domain of NdhS, where nine charged residues are highly conserved among plants. Systematic alteration of these sites with neutral glutamine revealed that only arginine 193 was required for high NDH activity in vivo. Further replacement of arginine 193 with negatively charged aspartate or glutamate or hydrophobic alanine significantly decreased the efficiency of ferredoxin-dependent plastoquinone reduction by NDH in ruptured chloroplasts. Similar results were obtained in in vivo analyses of NDH activity and electron transport. From these results, we propose that the positive charge of arginine 193 in the SH3-like domain of NdhS is critical for electrostatic interaction with ferredoxin in vivo. PMID:24225949

  6. Seroprevalence of Salmonella and Mycoplasma infection in backyard chickens in the state of Entre Rios in Argentina.

    PubMed

    Xavier, J; Pascal, D; Crespo, E; Schell, H L; Trinidad, J A; Bueno, D J

    2011-04-01

    The present work was conducted to study the seroprevalence of Salmonella, Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS) infection in backyard chickens located in Entre Ríos, Argentina, over 3 periods of time. A total of 2,441 sera samples were collected from backyard chickens belonging to 256 family farms in 16 counties in the state of Entre Ríos from January to May 2003 (first period), December 2004 to April 2005 (second period), and October 2006 to May 2007 (third period). The prevalence of family farms testing seropositive for Salmonella averaged 23.9, 15.9, and 28.6% during the first, second, and third period, respectively. The highest prevalence of Salmonella-seropositive farms recorded (66.7%) was on farms from Concordia county, and the lowest prevalence (0%) was on farms from La Paz county. In contrast, the prevalence of family farms seropositive for MG averaged 32.8, 55.1, and 76.2% during the first, second, and third periods, respectively. The highest prevalence of MG-seropositive farms (100%) was found in the counties of Victoria and Tala, and the lowest prevalence (8.7%) was found on farms on Colón county. The prevalence of family farms seropositive for MS averaged 68.6 and 100% during the first and second periods, respectively. The highest prevalence of MS-seropositive farms (100%) was on farms in 85% of the counties tested, and the lowest prevalence (21.7%) was on farms from Colón county. Salmonella, MG, and MS infection are present at high levels in backyard chicken farms, and this presents a high risk to commercial poultry production in Entre Ríos, the state with the highest chicken population and density in Argentina. PMID:21406358

  7. A gene in the Pseudomonas syringae pv. tomato Hrp pathogenicity island conserved effector locus, hopPtoA1, contributes to efficient formation of bacterial colonies in planta and is duplicated elsewhere in the genome.

    PubMed

    Badel, J L; Charkowski, A O; Deng, W L; Collmer, A

    2002-10-01

    The ability of Pseudomonas syringae to grow in planta is thought to be dependent upon the Hrp (type III secretion) system and multiple effector proteins that this system injects into plant cells. ORF5 in the conserved effector locus of the P. syringae pv. tomato DC3000 Hrp pathogenicity island was shown to encode a Hrp-secreted protein and to have a similarly secreted homolog encoded in an effector-rich pathogenicity island located elsewhere in the genome. These putative effector genes were designated hopPtoA1 and hopPtoA2, respectively. DNA gel blot analysis revealed that sequences hybridizing with hopPtoA1 were widespread among P. syringae pathovars, and some strains, like DC3000, appear to have two copies of the gene. uidA transcriptional fusions revealed that expression of hopPtoA1 and hopPtoA2 can be activated by the HrpL alternative sigma factor. hopPtoA1 and hopPtoA1/hopPtoA2 double mutants were not obviously different from wild-type P. syringae pv. tomato DC3000 in their ability to produce symptoms or to increase their total population size in host tomato and Arabidopsis leaves. However, confocal laser-scanning microscopy of GFP (green fluorescent protein)-labeled bacteria in Arabidopsis leaves 2 days after inoculation revealed that the frequency of undeveloped individual colonies was higher in the hopPtoA1 mutant and even higher in the hopPtoA1/hopPtoA2 double mutant. These results suggest that hopPtoA1 and hopPtoA2 contribute redundantly to the formation of P. syringae pv. tomato DC3000 colonies in Arabidopsis leaves. PMID:12437299

  8. In planta processing and glycosylation of a nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-like effector and its interaction with a host CLAVATA2-like receptor to promote parasitism.

    PubMed

    Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S; Mitchum, Melissa G; Wang, Xiaohong

    2015-01-01

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. PMID:25416475

  9. Función de luminosidad a partir de distancias fotométricas

    NASA Astrophysics Data System (ADS)

    Taverna, A.; Zandivarez, A.

    2015-08-01

    In this work we attempt to establish the statistical basis for the study of the evolution of populations of galaxies in the universe under different environments, through the analysis of the luminosity function of galaxies calculated in deep photometric catalogues with only photometric information. These catalogues will considerably increase the number and types of galaxies involved in future studies. The main aim of this work is to test the reliability of estimating the galaxy luminosity function calculated by using photometric redshifts as distance estimator. This work is oriented to a photometric catalogue in particular, the Javalambre Physics of the Accelerating Universe Astrophysical Survey, which will cover more than 8000 squere degrees and will have information in 54 narrow bands and 5 broad bands in the optical frecuency range, which will allow to obtain photometric redshifts with high accuracy. To perform the statistical tests, we used a mock galaxy catalogue constructed from the Millennium I simulation plus a semianalyticial model of galaxy formation which mimics the main properties of the future survey. This mock catalogue provides us a sample of synthetic galaxies with all the properties needed to study the problems involved in the determination of the luminosity function and its evolution. We analyzed the effectiveness of the method to recover the luminosity function obtained by using spectroscopic information. This allowed us to determine whether it is possible to obtain reliable results when attempting to study the evolution of the luminosity function using photometric redshifts.

  10. Clostridium perfringens growth from spore inocula in sous-vide processed pork-based Mexican entrée.

    PubMed

    Miguel-Garcia, Denise Y; Juneja, Vijay K; Valenzuela-Melendrez, Martin; Díaz-Cinco, Martha E; Thippareddi, H; Aida Peña-Ramos, E

    2009-01-01

    The combined effect of Citricidal wih irradiation on Clostridium perfringens growth from spores in a sous-vide processed marinated pork meat Mexican entrée was investigated. Citricidal was added at 200 or 800 ppm after mixing pork meat with tomatillo sauce and inoculated with 3 log(10) CFU/g of C. perfringens spores. Samples were irradiated at either 0 or 2 kGy, heated to an internal temperature of 71 degrees C, and stored at 4 degrees C for 28 d, 15 degrees C for 45 d, and 25 degrees C for 26 h. To simulate the conditions that may occur during transportation, distribution, storage, or handling in supermarkets or by consumers, the effect of static temperature abuse on C. perfringens growth was assessed by transferring samples stored at 4 to 25 degrees C for 13 and 15 h. Total C. perfringens populations were determined by plating diluted samples on tryptose-sulfite-cycloserine agar. Growth was not observed up to 45 d of storage at 15 degrees C in samples supplemented with 800 ppm of Citricidal. At 25 degrees C, no significant differences (P > 0.05) on the lag phase duration due to antimicrobial treatments was observed. The temperature abuse of refrigerated products for up to 15 h did not lead to C. perfringens growth to high infective dose levels of 1 million cells required to cause food poisoning. The results suggest that 800 ppm Citricidal can have significant bacteriostatic activity against C. perfringens and may provide a degree of protection against this pathogen in sous-vide processed marinated pork meat Mexican entrée, under mild temperature abuse (

  11. Simple quantification of in planta fungal biomass.

    PubMed

    Ayliffe, Michael; Periyannan, Sambasivam K; Feechan, Angela; Dry, Ian; Schumann, Ulrike; Lagudah, Evans; Pryor, Anthony

    2014-01-01

    An accurate assessment of the disease resistance status of plants to fungal pathogens is an essential requirement for the development of resistant crop plants. Many disease resistance phenotypes are partial rather than obvious immunity and are frequently scored using subjective qualitative estimates of pathogen development or plant disease symptoms. Here we report a method for the accurate comparison of total fungal biomass in plant tissues. This method, called the WAC assay, is based upon the specific binding of the plant lectin wheat germ agglutinin to fungal chitin. The assay is simple, high-throughput, and sensitive enough to discriminate between single Puccinia graminis f.sp tritici infection sites on a wheat leaf segment. It greatly lends itself to replication as large volumes of tissue can be pooled from independent experiments and assayed to provide truly representative quantification, or, alternatively, fungal growth on a single, small leaf segment can be quantified. In addition, as the assay is based upon a microscopic technique, pathogen infection sites can also be examined at high magnification prior to quantification if desired and average infection site areas are determined. Previously, we have demonstrated the application of the WAC assay for quantifying the growth of several different pathogen species in both glasshouse grown material and large-scale field plots. Details of this method are provided within. PMID:24643560

  12. Effect of grapefruit seed extract on thermal inactivation of Listeria monocytogenes during sous-vide processing of two marinated Mexican meat entrées

    Technology Transfer Automated Retrieval System (TEKTRAN)

    D and z values of Listeria monocytogenes were obtained for two Mexican meat entrées: pork meat marinated in tomatillo (green tomato) sauce (PTS) and beef marinated in a red chili sauce (BRCS), with addition of 0, 200 and 800 ppm of grapefruit seed extract (GSE). Meat samples, inoculated with L.monoc...

  13. A Process Evaluation of an Efficacious Family-Based Intervention to Promote Healthy Eating: The "Entre Familia: Reflejos de Salud" Study

    ERIC Educational Resources Information Center

    Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe

    2015-01-01

    "Entre Familia: Reflejos de Salud" was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker ("promotora") model with an entertainment-education…

  14. Soil Quality Indicators to Define Land Use in the Area of Native Forest of Entre Ríos, Argentina

    NASA Astrophysics Data System (ADS)

    Wilson, M. G.; Tasi, H. A.; Paz González, A.; Díaz, E. L.; Sasal, M. C.

    2012-04-01

    The main economic activity in the area of native forest of the province of Entre Ríos (Argentina) has long been the agricultural and/or livestock production, especially cattle breeding. In recent years, the proportion of agricultural crops in the rotations, especially that of soybean, has increased, thus leading to an increase in the need for land clearing to incorporate new lands for agricultural use. Most of these lands are considered marginal for agricultural use. In addition rice farming with irrigation is a critical part of the Entre Ríos economy. Defining and assessing soil quality indicators (SQI) that show the evolution of the soil with different uses and management systems is a way to contribute to the knowledge of soil quality. The aims of this study were to characterize the current land use and land tenure in the area of native forest of Entre Ríos, as well as to identify and select variables sensitive to agricultural and/or livestock use of the most representative soils of this area (indicators of the dynamic quality of the soil) and define the most appropriate land use according to land suitability and behavior of these indicators. We identified the most representative soil subgroups (corresponding to the orders Vertisols, Mollisols and Alfisols) and defined the production systems livestock-agricultural, agricultural-livestock, agricultural without irrigation, and rice crop irrigated with water from groundwater and surface reservoirs. We also determined the physical, physico-chemical, chemical and microbiological variables of the soil, and characterized the quality of the water for irrigation. We selected the SQI using Principal Components Analysis, to form a minimum data set (MDS). The change in the use of the land responded to a favorable economic situation for agriculture that started in the 1990's. The leasing and sharecropping schemes and the incidental contracts have become increasingly important, predominating over the undivided property. We

  15. State of Conservation of the Native Forests in Entre Ríos (Argentina) and Changes in Land Use

    NASA Astrophysics Data System (ADS)

    Sabattini, R. A.; Sione, S. M.; Ledesma, S. G.; Sabattini, J. A.; Wilson, M. G.

    2012-04-01

    The native forest area of Entre Ríos province (Argentina) is associated with a constant change in land use, with an increase in recent years in agricultural use, especially for soybean crop. In addition, since its inadequate management has triggered degradation processes of the natural forest structure, the implementation of strategies for the restoration and conservation of native forests has become a priority. The aim of this study was to diagnose the conservation state of the native forest in the basin of the Estacas Stream (Entre Ríos, Argentina) after the change in land use, to help design guidelines for the restoration and sustainable management of these ecosystems. The field study was conducted in October 2010, in a representative area of the native forest of 73,000 ha. Using Landsat 5-TM images (INPE), environments were separated by manual vectorization, identifying and classifying native forests and other lands (agricultural, urban). Using a field exploratory survey (58 geo-referenced sampling points), we developed patterns corresponding to the different types of forests, contrasting this information with the digital data of the images. The native forests were classified according to type (high/low forest, open/closed forest, savanna), successional stage (climax, successional or regeneration forest) and degree of disturbance (weed growth, erosion, fire), and their frequency determined. Each classification was assessed by a contingency matrix, and global reliability index and the Kappa index. The information obtained generated a classification map of native forests in the basin scale. We found that the native forest covered an area of 42,726.91 ha, accounting for 58.52% of the total basin area, and that the rest corresponded to other land uses. The most frequent native forests (59.09%) were climax forest, but accounted for only 8.2% of the basin area. Within this group, the most important were the low and open forest, with Prosopis affinis and Prosopis

  16. On acoplamento mecânico entre a antena e o transdutor no detector de ondas gravitacionais Mario Schenberg

    NASA Astrophysics Data System (ADS)

    Melo, J. L.; Aguiar, O. D.; Velloso, W. F., Jr.; Lucena, A. U.

    2003-08-01

    O detector de ondas gravitacionais MARIO SCHENBERG consistirá de uma massa esférica de cobre-alumínio de 1150kg resfriada a 4K, sobre a qual serão instalados 6 transdutores de nióbio. Com estes trandutores pretende-se converter um possível sinal de onda gravitacional detectado em sinal elétrico, para tanto é necessário que o acoplamento mecânico entre os transdutores e a massa ressonante seja o maior possível. Isto significa que o transdutor deve ser ressonante na mesma freqüência que a antena (aproximadamente 3200Hz). Neste trabalho foi desenvolvida uma geometria para a estrutura mecânica do trandutor. Isto foi feito criando-se modelos em elementos finitos usando-se o "software" MSC/Nastran. Estes modelos criados foram analisados estaticamente (cálculo de tensões) e dinamicamente (cálculo das freqüências de ressonâncias e seus respectivos modos normais) de maneira a se obter o primeiro modo normal do transdutor em 3200Hz. A partir destes cálculos escolheu-se a melhor geometria para o transdutor. Os próximos passos do trabalho serão: usinar este transdutor em uma barra de nióbio e testá-lo à temperatura ambiente e à baixa temperatura. Após isto, pretende-se testá-lo na própria antena resfriada.

  17. Half-size me? How calorie and price information influence ordering on restaurant menus with both half and full entrée portion sizes.

    PubMed

    Haws, Kelly L; Liu, Peggy J

    2016-02-01

    Many restaurants are increasingly required to display calorie information on their menus. We present a study examining how consumers' food choices are affected by the presence of calorie information on restaurant menus. However, unlike prior research on this topic, we focus on the effect of calorie information on food choices made from a menu that contains both full size portions and half size portions of entrées. This different focus is important because many restaurants increasingly provide more than one portion size option per entrée. Additionally, we examine whether the impact of calorie information differs depending on whether full portions are cheaper per unit than half portions (non-linear pricing) or whether they have a similar per unit price (linear pricing). We find that when linear pricing is used, calorie information leads people to order fewer calories. This decrease occurs as people switch from unhealthy full sized portions to healthy full sized portions, not to unhealthy half sized portions. In contrast, when non-linear pricing is used, calorie information has no impact on calories selected. Considering the impact of calorie information on consumers' choices from menus with more than one entrée portion size option is increasingly important given restaurant and legislative trends, and the present research demonstrates that calorie information and pricing scheme may interact to affect choices from such menus. PMID:26654889

  18. Tdp studies and tests for C. A. Energia Electrica de Venezuela (enelven) at planta ramon laguna, units RL-17 and RL-10. Volume 3. Unit RL-10 turbine generator condition assessment report and units RL-10 and RL-11 boiler feed pump conditon assessment report. Export trade information

    SciTech Connect

    Not Available

    1991-03-28

    The study, conducted by Babcock and Wilcox, was funded by the U.S. Trade and Development agency on behalf of Enelven. In order to maximize generated power output and minimize operating costs at Planta Ramon Laguna, tests were done to evaluate the condition of equipment at the plant. In order to identify any damage and determine the operating output of each unit, assessments were done of the furnaces, boilers, generators and boiler feed pumps being used in the plant. The report presents the results of these tests. This is the last of three volumes and it is divided into the following sections: (1) Condition Assessment of Unit RL-10 Turbine-Generator; (2) Condition Assessment of Unit RL-10 and RL-11 Boiler Feed Pumps.

  19. Cristallisation, syncristallisation, et alliages moléculaires entre le lorazépam et l'oxazépam

    NASA Astrophysics Data System (ADS)

    Mascherpa-Corral, D.; Mascherpa, G.; Chauvet, A.

    1993-04-01

    Le polymorphisme et pseudopolymorphisme du lorazépam et oxazépam ont été étudiés par analyse thermique, calorimétrie différentielle à balayage et diffraction de rayons X. Deux formes polymorphes du lorazépam et plusieurs mono et hemisolvates ont été isolés à partir de recristallisation dans divers soivants. Aucun polymorphisme ni solvate n'a été mis en évidence avec l'oxazépam. Les paramètres cristallographiques des phases isolées ont été déterminées. A 160 et 203°C, le lorazépam et l'oxazépam perdent respectivement une molécule d'eau pour donner après réarrangement la quinazolinecarboxaldéhyde correspondante. La syncristallisation des deux benzodiazépines dans le benzène conduit à des alliages moléculaires à miscibilité totale à l'état solide dans tout le domaine de concentration entre l'exazépam el la forme α du lorazépam, elle n'est que partielle avec la forme β. Thermal analysis, differential scanning calorimetry, and X-ray diffraction were carried out to study the polymorphism and pseudopolymorphism of lorazepam and oxazepam. Two polymorphic forms of lorazepam and several mono- or hemisolvates were obtained after recrystallization from various solvents. No polymorphic form or solvate has been found for oxazepam. The crystallographic parameters of these new phases were determined. Lorazepam and oxazepam can lose a molecule of water at 160 and 203°C, respectively, and rearrange to quinazolinecarboxaldehyde. Mixed crystals of the two benzodiazepines, after recrystallization from benzene, lead to molecular alloys with complete solid solubility between oxazepam and the α-form of lorazepam over the whole range of composition but only to partial solubility with the β-form of lorazepam.

  20. Relation entre les caractéristiques des table-bancs et les mesures anthropométriques des écoliers au Benin

    PubMed Central

    Falola, Stève Marjelin; Gouthon, Polycarpe; Falola, Jean-Marie; Fiogbe, Michel Armand; Nigan, Issiako Bio

    2014-01-01

    Introduction Le mobilier scolaire et la posture assise en classe sont souvent impliqués dans l'apparition des douleurs rachidiennes, influant de fait sur la qualité des tâches réalisées par les apprenants. Aucune étude n'a encore vérifié le degré d'adéquation entre les caractéristiques du mobilier et celles des écoliers au Bénin. L'objectif de cette étude transversale est donc de déterminer la relation entre les dimensions des table-bancs utilisées en classe et les mesures anthropométriques des écoliers au Bénin. Methods Elle a été réalisée avec un échantillon probabiliste de 678 écoliers, âgés de 4 à 17 ans. Les mesures anthropométriques des écoliers et les mensurations relatives aux longueurs, largeurs et hauteurs des table-bancs ont été mesurées, puis intégrées aux équations proposées dans la littérature. Les pourcentages des valeurs situées hors des limitesacceptables, dérivées de l'application des équations ont été calculés. Results La largeur et la hauteur des table-bancs utilisées par les écoliers étaient plus élevées (p < 0,05) que les valeurs de référence recommandées par les structures officielles de contrôle et de production des mobiliers scolaires au Bénin. Quel que soit le sexe, il y avait une inadéquation entre la largeur du banc et la longueur fesse-poplité, puis entre la hauteur de la table et la distance coude-bancdes écoliers. Conclusion Les résultats suggèrent de prendre en compte l’évolution des mesures anthropométriques des écoliers dans la confection des table-bancs, afin de promouvoir de bonnes postures assises en classe et de réduire le risque de troubles du rachis. PMID:25317232

  1. Effect of Grapefruit Seed Extract on Thermal Inactivation of Listeria monocytogenes during Sous-Vide Processing of Two Marinated Mexican Meat Entrées.

    PubMed

    Valenzuela-Melendres, Martin; Peña-Ramos, E Aida; Juneja, Vijay K; Camou, Juan Pedro; Cumplido-Barbeitia, German

    2016-07-01

    D- and z-values for Listeria monocytogenes were obtained for two Mexican meat entrées: pork meat marinated in tomatillo (green tomato) sauce (PTS) and beef marinated in a red chili sauce (BRCS), with addition of 0, 200, and 800 ppm of grapefruit seed extract (GSE). Meat samples inoculated with L. monocytogenes were packaged in sterile bags, immersed in a water bath, and held at 55, 57.5, 60, and 62.5°C for different periods of time. Depending upon the temperature, D-values at 0 ppm of GSE ranged from 26.19 to 2.03 min in BRCS and 26.41 to 0.8 min in PTS. Adding 800 ppm of GSE to BRCS thermally treated at 55 and 62.5°C significantly decreased inactivation time by 35%. A reduction in time of 25.9, 10.6, and 40.1% at 55, 57.5, and 60°C, respectively, was observed in PTS with 800 ppm of GSE. The z-values of L. monocytogenes were not significantly affected by GSE addition; average z-values were 7.25 and 5.09°C for BRCS and PTS, respectively. Estimated thermal lethality for a 7-D log reduction of L. monocytogenes under commercial-size sous-vide conditions at a reference temperature of 55°C was reached at 78 and 71 min for BRCS without and with 800 ppm of GSE, respectively. For PTS, 7-D reduction was attained at 69 and 61 min without and with addition of 800 ppm of GSE, respectively. Supplementing both Mexican meat entrées (BRCS and PTS) with 800 ppm of GSE rendered L. monocytogenes cells more sensitive to the lethal effect of heat. The results of this study will assist the retail food industry in designing acceptance limits on critical control points pertaining to cooking regimes to effectively eliminate L. monocytogenes in BRCS and PTS sous-vide processed Mexican meat entrées. PMID:27357037

  2. In planta mutagenesis of Src homology 3 domain-like fold of NdhS, a ferredoxin-binding subunit of the chloroplast NADH dehydrogenase-like complex in Arabidopsis: a conserved Arg-193 plays a critical role in ferredoxin binding.

    PubMed

    Yamamoto, Hiroshi; Shikanai, Toshiharu

    2013-12-20

    Chloroplast NADH dehydrogenase-like (NDH) complex mediates cyclic electron transport around photosystem I and chlororespiration in angiosperms. The Src homology 3 domain (SH3)-like fold protein NdhS/CRR31 is an NDH subunit that is necessary for high affinity binding of ferredoxin, indicating that chloroplast NDH functions as a ferredoxin:plastoquinone oxidoreductase. However, the mechanism of the interaction between NdhS and ferredoxin is unclear. In this study, we analyzed their interaction in planta by using site-directed mutagenesis of NdhS. In general, binding of ferredoxin to its target proteins depends on electrostatic interaction. In silico analysis predicted the presence of a positively charged pocket in the SH3-like domain of NdhS, where nine charged residues are highly conserved among plants. Systematic alteration of these sites with neutral glutamine revealed that only arginine 193 was required for high NDH activity in vivo. Further replacement of arginine 193 with negatively charged aspartate or glutamate or hydrophobic alanine significantly decreased the efficiency of ferredoxin-dependent plastoquinone reduction by NDH in ruptured chloroplasts. Similar results were obtained in in vivo analyses of NDH activity and electron transport. From these results, we propose that the positive charge of arginine 193 in the SH3-like domain of NdhS is critical for electrostatic interaction with ferredoxin in vivo. PMID:24225949

  3. A Process Evaluation of an Efficacious Family-Based Intervention to Promote Healthy Eating: The Entre Familia: Reflejos de Salud Study.

    PubMed

    Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe

    2015-10-01

    Entre Familia: Reflejos de Salud was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker (promotora) model with an entertainment-education component. This process evaluation examined intervention implementation and assessed relationships between implementation factors and dietary change. Participants included 180 mothers randomized to an intervention condition. Process evaluation measures were obtained from participant interviews and promotora notes and included fidelity, dose delivered (i.e., minutes of promotora in-person contact with families, number of promotora home visits), and dose received (i.e., participant use of and satisfaction with intervention materials). Outcome variables included changes in vegetable intake and the use of behavioral strategies to increase dietary fiber and decrease dietary fat intake. Participant satisfaction was high, and fidelity was achieved; 87.5% of families received the planned number of promotora home visits. In the multivariable model, satisfaction with intervention materials predicted more frequent use of strategies to increase dietary fiber (p ≤ .01). Trends suggested that keeping families in the prescribed intervention timeline and obtaining support from other social network members through sharing of program materials may improve changes. Study findings elucidate the relationship between specific intervention processes and dietary changes. PMID:25810469

  4. Uma Comparação entre Técnicas de Propagação de Erros em Astrofísica: Monte Carlo x Bootstrap

    NASA Astrophysics Data System (ADS)

    Zabot, Alexandre; Baptista, Raymundo

    2005-07-01

    Neste trabalho é feito um estudo comparativo entre dois algoritmos numéricos usados para propagação de erros em dados experimentais. Um deles é conhecido por Método de Monte carlo e o outro por Método de Bootstrap. Recentemente, Dhullon & Watson argüiram que a aplicação do método de Monte Carlo introduz ruído nos dados, e propuseram então a utilização do Bootstrap como alternativa capaz de produzir resultados superiores. O objetivo deste trabalho é testar a validade dessa afirmação. As duas técnicas foram aplicadas a três problemas diferentes: o ajsute de modelos de emissão LTE simples e atmosfera estelar a espectros estelares observados e o ajuste de curvas de luz de eclipses de Variáveis Cataclísmicas para a detemrinação da distribuição radial de brilho dos seus discos de acréscimo. Os métodos foram testados quanto à sua robusteza, ou seja, a capacidade de prover resultados coerentes enre si. Além disso, as soluções dos métodos foram comparadas. Os resultados indicam que não existe evidência de superioridade de um métodos em relação ao outro.

  5. In Planta mutagenesis determines the functional regions of puroindoline proteins.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    PINA and PINB functionally comprise the wheat (Triticum aestivum L.) Ha locus which controls grain texture and many wheat end-use properties. PINs in their functional forms impart soft texture and a mutation in either PIN is found in all hard wheats. Studies of the PINs mode of action is limited ...

  6. Selective Effect of Pesticides on Plant--A Review.

    PubMed

    Parween, Talat; Jan, Sumira; Mahmooduzzafar, Sumira; Fatma, Tasneem; Siddiqui, Zahid Hameed

    2016-01-01

    This review represents systematic and integrated picture of pesticide exposure to plant and its effect on growth and metabolism. Decades ago, agrochemicals were introduced aiming at enhancing crop yields and protecting crops from pests. Due to adaptation and resistance developed by pests to chemicals, every year higher amounts and new chemical compounds are used to protect crops, causing undesired side effects and raising the costs of food production. Biological chemical free agriculture is gaining also more and more support but it is still not able to respond to the need for producing massive amounts of food. The use of agrochemicals, including pesticides, remains a common practice especially in tropical regions and South countries. Cheap compounds, such as DDT, HCH, and Lindane, that are environmentally persistent, are today banned from agriculture use in developed countries, but remain popular in developing countries. As a consequence, persistent residues of these chemicals contaminate food and disperse in the environment. Therefore, the thrust of this paper was to review the application of pesticides effect early from germination to growth of the plant, leading to alteration in biochemical, physiological and different enzymatic and non-enzymatic antioxidants which ultimately affect the yield and resulted in residues in plant, vegetables, and fruits. PMID:25216296

  7. Métastases cutanées vues au laboratoire d'anatomie pathologique à Lomé, Togo entre 2005 et 2014

    PubMed Central

    Darre, Tchin; Saka, Bayaki; Landoh, Dadja Essoya; Mouhari-Toure, Abas; Amegbor, Koffi; Pitché, Palokinam; Napo-Koura, Gado

    2015-01-01

    Introduction L'objectif de cette étude était de documenter le profil épidémiologique et histologique des métastases cutanées vues au laboratoire d'anatomie pathologique (LAP) de Lomé. Méthodes Il s'agissait d'une étude descriptive et transversale portant sur des cas de métastases cutanées observées au LAP du CHU Sylvanus Olympio entre 2005 et 2014. Résultats Au cours de cette période d’étude, nous avons recensé 32 cas de métastases cutanées représentant 3,2% (1005 cas) de l'ensemble des cas de métastases enregistrées au LAP. L’âge moyen des patients atteints de ces métastases cutanées était de 42,6 ans et le sex-ratio (F/H) de 2,2. Sur le plan macroscopique, ces métastases étaient nodulaires dans 15 cas, bourgeonnantes dans 12 cas, ulcéré dans 3 cas et ulcéro-bourgeonnant dans 2 cas. Les types histologiques étaient représentés par les adénocarcinomes (19 cas, 59,4%), les carcinomes épidermoïdes (8 cas, 25%), la maladie de Paget (3 cas, 9,4%), le carcinome à petites cellules du type neuroendocrine (un cas, 3,1%) et le mélanome (un cas, 3,1%). Selon le degré de différenciation, les métastases cutanées étaient bien différenciées dans 14 cas (56%). Les principales localisations de ces métastases cutanées étaient le thorax (11 cas, 34,4%) suivi de l'abdomen (10 cas, 31,3%). Les cancers primitifs étaient surtout d'origine mammaire (14 cas, 43,7%). Conclusion Cette étude montre que les métastases cutanées sont relativement rares et les tumeurs malignes d'origine mammaire sont les tumeurs primitives prédominantes. Avec un pourcentage élevé des formes peu différenciées et celles indifférenciées, l'amélioration du plateau technique du LAP (immunohistochimie) permettra d'accroitre ses capacités diagnostiques. PMID:27047627

  8. A Reappraising of Cosmography: the Interface Between Astronomical and Geographic Studies. (Breton Title: Releitura do Conceito de Cosmografia: a Interface Entre os Estudos Astronômicos e Geográficos.) Una Relectura del Concepto de Cosmografía: la Interfase Entre los Estudios Astronómicos y Geográficos

    NASA Astrophysics Data System (ADS)

    Azevedo Sobreira, Paulo Henrique

    2012-12-01

    The concept of "Cosmography" is in disuse since the 80s of the last century, but the astronomical themes previously discussed in the school subjects of Geography and Cosmography remain in current textbooks. The use of term "Cosmography" was rescued in this research, and the study of its re-signification prompted the appearance of the term Geographic Cosmography. The Geographic Cosmography is a field of studies of the Geography, whose set of knowledge and skills is predominantly scholar. It studies the interface between terrestrial and celestial knowledge, and assigns a geographic significance to them. It examines human and natural relationships with Sidereal Space and its consequences for society and nature. O conceito de "Cosmografia" está em desuso desde os anos 80 do século XX, mas os temas astronômicos anteriormente abordados nas disciplinas escolares de Cosmografia e de Geografia permanecem nos atuais livros didáticos. O uso do termo "Cosmografia" foi resgatado nesta pesquisa e o estudo de sua ressignificação proporcionou o surgimento do termo Cosmografia Geográfica. A Cosmografia Geográfica é um campo de estudos da Geografia, cujo conjunto de conhecimentos e habilidades é predominantemente escolar. Estuda a interface entre os conhecimentos terrestres e os celestes e lhes atribui significância geográfica. Analisa as relações humanas e naturais com o Espaço Sideral e suas consequências para a sociedade e a natureza.

    Aunque el concepto de "Cosmografía" no se usa desde la década de los '80 del siglo pasado, los temas astronómicos que se enseñaban anteriormente en las asignaturas escolares de Cosmografía y de Geografía permanecen en los actuales libros didácticos. El uso del término "Cosmografía" fue rescatado en esta investigación y el estudio de su resignificación proporcionó el surgimiento del término Cosmografía Geográfica. La Cosmografía Geográfica es un campo de estudio de la Geografía, donde

  9. Etude des phenomenes chimiques au contact entre le bloc cathodique et la barre collectrice d'une cellule d'electrolyse d'aluminium

    NASA Astrophysics Data System (ADS)

    Lebeuf, Martin

    La production d'aluminium est une industrie importante au Québec. Les propriétés de ce métal le vouent à de multiples usages présents et futurs dans le cadre d'une économie moderne durable. Toutefois, le procédé Hall-Héroult est très énergivore et des progrès demeurent donc nécessaires pour en diminuer les coûts financiers et environnementaux. Parmi les améliorations envisageables de la cellule d'électrolyse se trouve le contact entre la cathode et la barre collectrice, qui doit offrir une faible résistivité au passage du courant électrique. En cours d'opération de la cellule, ce contact a tendance à se dégrader, générant des pertes énergétiques significatives. Les causes de cette dégradation, pouvant provenir de phénomènes chimiques, thermiques, mécaniques et/ou électriques, demeurent mal comprises. Le but du présent projet était donc d'étudier les phénomènes chimiques se produisant au contact bloc-barre de la cellule d'électrolyse Hall-Héroult. En premier lieu, un aspect crucial à considérer est la pénétration du bain électrolytique dans la cathode, car des composés de bain atteignent éventuellement la barre collectrice et peuvent y réagir. A cet effet, une méthode novatrice a été développée afin d'étudier les cathodes et la pénétration du bain dans celles-ci à l'aide de la microtomographie à rayons X. Cette méthode rapide et efficace s'est avérée fort utile dans le projet et a un potentiel important pour l'étude future des cathodes et des phénomènes qui s'y produisent. Ensuite, une cellule d'électrolyse rectangulaire à petite échelle a été développée. Plusieurs phénomènes observés 'en industrie sur des autopsies de cellules post-opération et rapportés dans la littérature ont été reproduis avec succès à l'aide de cette cellule expérimentale. Puis, des tests sans électrolyse, ciblant l'effet du bain électrolytique sur l'acier, ont aussi été conçus et complétés afin de s

  10. Le renforcement de l'interface entre les services de santé publique et de première ligne : enjeux et pistes de solution

    PubMed Central

    Paquette, Daniel; Reinharz, Daniel

    2009-01-01

    Le développement de liens étroits entre la santé publique et les services cliniques, notamment ceux offerts par les médecins de famille œuvrant en première ligne, est prôné dans tous systèmes de santé occidentaux. On suppose que les collaborations formant une telle interface ont des impacts positifs à la fois sur la qualité des soins, sur le fardeau des maladies et sur l'équité dans le système de santé. Si les acteurs des deux domaines admettent le bien-fondé de l'interface et favorisent en principe son développement, plusieurs barrières nuisent aux collaborations dans la réalité. Or, peu est connu sur ces barrières dans le système de santé québécois. Cette étude vise à répondre à ce manque d'information en étudiant l'interface à partir d'une perspective organisationnelle. Deux cadres conceptuels ont été utilisés, soit la typologie de Lasker (1997) et les archétypes de Hinings et Greenwood (1988). L'analyse met en évidence deux des six formes de collaboration proposées par la typologie utilisée, soit la coordination des services aux individus et la mise à profit des rencontres cliniques pour les fins de la santé publique. Les activités associées à ces formes de collaboration, qui sont importantes eu égard au mandat de la santé publique, comportent un intérêt essentiellement pour la santé publique et sont déterminées en pratique unilatéralement par cette dernière. En outre, le manque de coordination des activités qui impliquent une collaboration avec les médecins constitue un obstacle au développement de telles activités en créant des irritants pour les médecins. Il y a donc, dans le système de santé québécois, des possibilités de développement de l'interface là où la collaboration se fait également au profit du travail clinique et là où elle tient compte des contraintes du milieu clinique. PMID:20436801

  11. Pincharse sin infectarse: estrategias para prevenir la infección por el VIH y el VHC entre usuarios de drogas inyectables

    PubMed Central

    MATEU-GELABERT, P.; FRIEDMAN, S.; SANDOVAL, M.

    2011-01-01

    infectarse por el VIH (sólo un doble negativo tuvo un amplio conocimiento sobre la hepatitis C). Estas intencionalidades no son mutuamente excluyentes. La presencia de varias refuerza la puesta en práctica a diario de comportamientos que pueden ayudar al que se inyecta a mantenerse libre de infecciones durante años. Algunas prácticas que hemos identificado se implementan en grupo y se comunican de UDI a UDI, de esta manera se extienden entre algunas redes sociales de UDI. Conclusiones Los UDI que permanecen sin infectarse planean e implementan estrategias de prevención en circunstancias donde otros UDI aplican prácticas de riesgo. El mantenimiento de la no infección no es, por lo tanto, un resultado del azar, sino más bien el resultado del esfuerzo (agencia) de los UDI. Investigar y extender estas estrategias y tácticas a través de programas de prevención podría contribuir a la prevención del VIH y el VHC. PMID:21915175

  12. Le transfert de connaissances entre les mathematiques et les sciences. Une etude exploratoire aupres d'eleves de 4e secondaire

    NASA Astrophysics Data System (ADS)

    Samson, Ghislain

    2003-06-01

    Au moment ou dans plusieurs pays on travaille a refondre les programmes d'etudes, tant au primaire qu'au secondaire, l'interet pour le transfert renait. Un des concepts fondamentaux en apprentissage consiste en l'habilete a reutiliser de facon consciente et efficace un acquis d'une situation a une autre situation. Cette recherche emane de preoccupations professionnelles au moment ou le chercheur etait enseignant au secondaire. Au cours de ces annees, il lui a ete possible de constater que plusieurs eleves percevaient difficilement les liens presents entre les disciplines mathematiques et scientifiques. Des travaux en psychologie cognitive et plus particulierement selon une perspective du traitement de l'information ont servi de cadre de reference pour evaluer et analyser les capacites de transfert aupres d'eleves de 4e secondaire. Ce cadre de reference permet de formuler le principal objectif qui est de mieux comprendre le processus de transfert chez des eleves en situation de resolution de problemes scientifiques. Cette these s'interesse donc au transfert en tant que phenomene important du processus d'apprentissage au sens de l'integration. La methode de recherche choisie, de nature qualitative, est principalement axee sur l'evaluation de la capacite a transferer des connaissances lors d'une epreuve et d'un entretien. Pour evaluer ce potentiel de transfert, nous avons elabore deux outils: une epreuve en mathematiques et en sciences et un guide d'entretien. Pour la passation de l'epreuve, le chercheur a pu compter sur la collaboration de 130 sujets provenant de deux ecoles. L'entretien complete la prise de donnees avec 13 sujets ayant accepte de poursuivre l'etude. Les donnees recueillies par ces instruments font ensuite l'objet d'une analyse de contenu. En premier lieu, les verbatims de l'epreuve et de l'entretien ont ete transcrits, puis codifies. La correction des reponses fournies pour les problemes resolus s'est faite a partir d'une grille d

  13. Association entre les hormones sexuelles, les marqueurs de remodelage osseux et la densité minérale osseuse chez des femmes ménopausées d'origine marocaine (étude transversale)

    PubMed Central

    El Maataoui, Aissam; Biaz, Asmae; El Boukhrissi, Fatima; El Machtani, Si; Dami, Abdellah; Bouhsain, Sanae; Bamou, Youssef; El Maghraoui, Abdellah; Ouzzif, Zhor

    2015-01-01

    Introduction Le présent travail se propose d’étudier la relation entre les hormones sexuelles, notamment l’œstradiol et l'indice de l’œstradiol libre, le sulfate de déhydroépiandrosterone et la sex hormone binding globulin, les marqueurs de remodelage osseux et la densité minérale osseuse chez une population de femmes marocaine ménopausées. Méthodes Il s'agit d'une étude transversale, menée sur une période de 6 mois d'octobre 2012 à fin avril 2013 et ayant fait participer deux cent deux (202). Résultats L’œstradiol et l'indice d’œstradiol libre (IEL) ont montré une corrélation négative respectivement à l'ostéocalcine (OC), à la crosslaps (β-CTX) et l'OC (p<0.001). La sulfate de déhydroepiandrosterone S-DHEA a été corrélée positivement à l'OC (p<0.001), alors que e taux sérique de la sex hormone binding globulin (SHBG) l'a été corrélé à la β-CTX et l'OC (p<0.001). Par ailleurs, une corrélation positive a été établie entre la densité minérale osseuse (DMO) au col de fémur et le poids, l'indice de masse corporelle (IMC), l'IEL et la S-DHEA. Une corrélation négative a été retrouvée entre la DMO au col de fémur d'une part et l’âge, la DDR, la SHBG, la β-CTX et l'OC d'une autre part. Conclusion Le présent travail montre que l'augmentation de l’âge et la diminution de l’œstradiol libre expliquent la diminution de la DMO au niveau du col du fémur, alors que l'augmentation du taux sérique de la SHBG et la diminution du poids expliquent la diminution de la DMO au rachis lombaire. PMID:26848353

  14. Un modelo para el control de calidad academica de los textos de instruccion a distancia (A Model for Controlling the Academic Quality of Distance Education Texts).

    ERIC Educational Resources Information Center

    Bolanos-Mora, Guiselle; And Others

    1992-01-01

    In response to the need for a system of control over the academic quality of distance education texts, this article proposes a methodological model based on criteria that evaluate written materials based on their instructional quality, design, and production. A discussion and figures evaluate educational aspects of content, communication,…

  15. El Programa de Educacion a Distancia de la Universidad Nacional Autonoma de Mexico (UNAM) (The Distance Education Program at the National Autonomous University of Mexico (UNAM)).

    ERIC Educational Resources Information Center

    Manilla, Jose Manuel Alvarez

    1996-01-01

    Describes the development of a distance education program at the National Autonomous University of Mexico (UNAM) which will meet several needs: lifelong learning; adult education; service to remote populations; and continuing education for faculty in remote campuses. Provision of large-scale education depends on addressing issues dealing with…

  16. La efectividad de la educacion a distancia como metodologia en la desarrollo de destrezas de pensamiento (Effectiveness of Distance Education as a Methodology for Developing Thinking Skills).

    ERIC Educational Resources Information Center

    Melendez Alicea, Juan

    1992-01-01

    Presents steps taken in designing, justifying, and implementing an experimental study designed to investigate the effectiveness of distance education as a methodology for developing thinking skills. A discussion reviews major findings of the study by comparing student experiences from multimedia distance education and student experiences from…

  17. Competition entre supraconductivite et magnetisme au voisinage de la transition de Mott dans le conducteur organique quasi-bidimensionnel k-(BEDT-TTF)2copper[N(CN)2]bromine

    NASA Astrophysics Data System (ADS)

    Fournier, David

    Les conducteurs organiques quasi-bidimensionnels kappa-ET2X presentent d'importantes similitudes avec les SCHT telles qu'une phase isolant de Mott, un regime de pseudogap et un etat supraconducteur. L'etude de leurs proprietes apparait donc complementaire. Parmi les interrogations persistantes concernant la physique de ces systemes, l'origine du (ou des) processus exotique d'appariement, responsable de la supraconductivite est le sujet suscitant l'interet le plus marque dans la communaute. L'hypothese d'un mecanisme lie a la proximite d'un etat antiferromagnetique est privilegiee. Une etape importante dans la resolution de cette problematique est l'identification de la symetrie du parametre d'ordre. D'apres de nombreux travaux sur les systemes fortement correles, la sonde ultrasonore, de par sa sensibilite aux excitations de quasiparticule a basse temperature, est consideree comme particulierement adaptee a l'etude de cette propriete. Cependant, son emploi necessite l'utilisation d'un compose metallique a basse temperature et completement supraconducteur. Le compose metallique organique kappa-ET 2Cu[N(CN)2]Br presente toutes les caracteristiques necessaires a l'etude de cette propriete. En effet, il est situe loin de la transition du premier ordre de Mott et est completement supraconducteur. De facon surprenante, ce systeme semble se coupler fortement avec le reseau ce qui augmente significativement la sensibilite de cette sonde aux proprietes du gaz electronique. Cependant, des difficultes techniques importantes, liees a la nature intrinseque de ce materiau, doivent etre surmontees pour proceder a des mesures suivant differentes polarisations. La presente etude a profondement modifie notre comprehension de ce systeme. En effet, ces mesures ont permis de constater que le kappa-ET2Cu[N(CN)2]Br est un compose qui est situe en bordure de la zone de coexistence entre la supraconductivite et le magnetisme, ce qui constitue un resultat totalement inattendu. De plus, la

  18. Factores socio-económicos asociados a la percepción de situación socioeconómica entre adultos mayores de dos países latinoamericanos

    PubMed Central

    Brenes-Camacho, Gilbert

    2014-01-01

    El objetivo principal del artículo es estudiar la asociación entre la percepción subjetiva sobre la situación económica propia y una serie de medidas objetivas de bienestar socioeconómico –fuentes de ingresos, tenencia de vivienda, nivel educativo y transferencias familiares informales de dinero- entre adultos mayores de dos países Latinoamericanos: México y Costa Rica. Los datos se obtienen de las primeras rondas de dos encuestas sobre envejecimiento: CRELES para Costa Rica y ENASEM para México. La variable dependiente más importante se obtiene de las respuestas a las pregunta “¿Cómo califica su situación económica actual?” en Costa Rica y “¿Diría usted que su situación económica es…?” en México. Para ambas encuestas, las respuestas se codificaron en forma binaria; el código 0 representa las categorías Excelente, Muy buena y Buena, y el código 1 representa a las categorías Regular y Mala. Se encontró que el ingreso por jubilación es un importante determinante de la percepción de bienestar en ambos países. En Costa Rica, el ingreso del cónyuge y la tenencia de vivienda son importantes predictores de la percepción de bienestar, mientras que en México, los ingresos por transferencias están fuertemente asociados con dicha percepción. PMID:25360057

  19. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires.

    PubMed

    Balán, Iván C; Carballo-Diéguez, Alex; Marone, Rubén O; Pando, María A; Barreda, Victoria; Avila, María M

    2011-03-01

    El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  20. Determinação de elementos próprios dos asteróides troianos: comparação entre as teorias semi-analítica e sintética

    NASA Astrophysics Data System (ADS)

    Roig, F.; Beaugé, C.

    2003-08-01

    Além do cálculo semi-analítico de elementos próprios dos asteróides Troianos (Beaugé & Roig 2001, Icarus 153, 391), recentemente foi apresentado um novo conjunto destes elementos próprios determinado através de uma teoria sintética (Knenezevic & Milani 2003, comunicação pessoal). As bases de dados contendo estas determinações estão disponiveis na pagina web do Asteroid Dynamical Site (http://hamilton.dm.unipi.it/cgi-bin/astdys/astibo). Nesta comunicação apresentamos os primeiros resultados de um estudo comparativo entre ambos conjuntos de elementos próprios, analisando suas vantagens e desvantagens, assim como os limites de precisão de cada conjunto. Mostramos que os elementos próprios sintéticos são mais precisos que os smi-analíticos para grandes amplitudes de libração do ângulo s = l-lJup, embora acontece o contrario para os corpos cuja amplitude de libração é muito pequena. Finalmente discutimos a influencia destes erros na determinação de familias de asteroides e da estrutura resonante em torno dos pontos Lagrangeanos L4 e L5.

  1. Aceptabilidad del diagnóstico rápido casero para HIV entre hombres gay y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires

    PubMed Central

    Balán, Iván C.; Carballo-Diéguez, Alex; Marone, Rubén O.; Pando, María A.; Barreda, Victoria; Ávila, María M.

    2011-01-01

    Resumen El uso del diagnóstico rápido para HIV en Argentina, así como otros países de Latinoamérica, ha sido limitado hasta el momento. Este trabajo reporta los resultados provenientes de un estudio cualitativo realizado entre hombres gays y otros hombres que tienen sexo con hombres (G&HSH) de la Ciudad de Buenos Aires, Argentina. El objetivo principal del mismo fue conocer las ventajas y desventajas que los hombres G&HSH perciben en relación al diagnóstico rápido casero para HIV. Se realizaron ocho grupos focales con 73 participantes en los cuales se discutió acerca de las ventajas y desventajas del uso de los diagnósticos rápidos. Las respuestas fueron codificadas utilizando un programa para análisis de datos cualitativos (NVivo) y analizadas temáticamente. Los participantes describieron numerosas ventajas sobre el uso del diagnóstico rápido casero, aunque algunos reportaron importantes preocupaciones dentro de las cuales se destaca la posibilidad de impulsos suicidas si alguien recibe un resultado positivo estando solo. En términos generales se observó una gran aceptabilidad para el uso del diagnóstico rápido si el mismo es realizado por personal de salud en lugares acondicionados para este fin. PMID:25284951

  2. Traces de l'interaction entre galaxies

    NASA Astrophysics Data System (ADS)

    Duc, Pierre-Alain

    2016-08-01

    Within a galaxy, collisions between stars are exceptional; collisions between galaxies are themselves much more frequent. They are even supposed to play a major role in the formation of structures according to the standard hierarchical cosmological model. Gravitational interactions, tidal forces and following mergers shape the morphology of galaxies, and leave vestiges which can survive for a few Gyr. They consist of stellar shells, streams, tails and plumes which emit a diffuse and extended optical light. Several deep imaging projects use telescopes of all sizes to try to detect this light. We detail here what the census of collisional debris can tel us about the past history of galaxies and about the models and simulations supposedly accounting for it.

  3. A Concepção de Universo entre Alunos do Ensino Médio de São Paulo e suas Fontes de Aquisição

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2006-08-01

    Nesse trabalho procurou-se identificar por meio de um questionário as concepções de Universo, de espaço e tempo que sustentam a visão de mundo de um grupo de 270 estudantes de Ensino Médio, pertencentes a três escolas de São Paulo. As questões relacionadas aos conhecimentos prévios dos estudantes permitiram constatar que há pouco conhecimento acerca dos temas investigados, destacando-se que apenas 20% dos alunos foram capazes de relacionar as semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo, verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% concebiam o Sol como uma estrela. No que se refere às fontes de aquisição que proporcionaram esses conhecimentos, apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de Ast! ronomia, verificou-se claramente que para a maioria dos alunos seus conceitos ainda são inadequados, havendo necessidade de aprimoramento da abordagem desses conteúdos, pois apesar de popular, a Astronomia ainda é veiculada de maneira pouco esclarecedora e com imprecisões. Nesse contexto, são discutidas algumas possíveis contribuições que podem ser dadas para o ensino de Astronomia pelo uso das ferramentas computacionais nas escolas.

  4. Distinción Empírica Entre Engagement y Trabajolismo en Enfermeras Hospitalarias de Japón: Efecto Sobre la Calidad del Sueño y el Desempeño Laboral

    PubMed Central

    Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B.

    2016-01-01

    Objetivo El objetivo de este estudio es demostrar la distinción entre engagement y trabajolismo, estudiando su relación con la calidad del sueño y el desempeño laboral. Método Un total de 447 enfermeras de 3 hospitales de Japón fueron entrevistadas mediante un cuestionario autoadministrado que incluía la escala Utrecht (UWES, Utrecht Work Engagement Scale), la Escala de Adicción al Trabajo Holandesa (DUWAS, Dutch Workaholism Scale), preguntas sobre la calidad del sueño (7 ítems) con respecto a (1) dificultad para conciliar el sueño, (2) dificultad para mantener el sueño, (3) despertar temprano por la mañana, (4) dormirse o tomar siestas durante el día, (5) somnolencia diurna excesiva en el trabajo, (6) dificultad para despertarse por la mañana, y (7) despertar cansado en la mañana, y el Cuestionario sobre Salud y Desempeño (CSD) de la Organización Mundial de la Salud. Resultados Los modelos de ecuaciones estructurales demostraron que el engagement se relaciona positivamente con la calidad del sueño y el rendimiento laboral, mientras que el trabajolismo tiene una relación negativa con la calidad del sueño y el desempeño laboral. Conclusión Los resultados indican que el engagement y el trabajolismo son conceptualmente diferentes. El primero tiene una connotación positiva, mientras que el segundo se asocia de manera negativa al bienestar (buena calidad del sueño y buen rendimiento en el trabajo). PMID:26752805

  5. L’annonce d’une déficience motrice cérébrale : Une relation de confiance à construire entre les parents, le personnel paramédical et les médecins

    PubMed Central

    Pelchat, Diane; Lefebvre, Hélène; Bouchard, Jean-Marie

    2001-01-01

    RÉSUMÉ : L’annonce d’une déficience motrice cérébrale et des incapacités qui en découlent est une situation difficile à vivre pour les parents et les dispensateurs de soins (personnel paramédical et médecins). Un examen de la documentation médicale démontre que depuis vingt ans, le nombre de parents insatisfaits n’a pas changé. L’étude de type qualitatif et exploratoire, effectuée à la demande de milieux de réadaptation, vise à décrire le processus d’annonce d’un diagnostic de déficience motrice cérébrale (DMC) à partir de l’expérience des différents acteurs en cause et à déterminer les facteurs qui facilitent ou compliquent la relation de confiance. Les résultats indiquent que les parents et les dispensateurs de soins vivent dans deux mondes de perception différents au moment de l’annonce, lesquels se rejoignent difficilement. Les parents sont envahis par le drame qu’ils vivent, tandis que les médecins sont concentrés sur le contenu à transmettre aux parents. Cette annonce provoque une importante incertitude qui bloque la communication entre les partenaires, mais elle pourrait devenir un stimulant à de nouvelles stratégies d’adaptation. PMID:20084263

  6. Establishing the Empirical Relationship Between Non-Science Majoring Undergraduate Learners' Spatial Thinking Skills and Their Conceptual Astronomy Knowledge. (Spanish Title: Estableciendo Una Relación Empírica Entre el Razonamiento Espacial de los Estudiantes de Graduación de Carreras no Científicas y su Conocimento Conceptual de la Astronomía.) Estabelecendo Uma Relação Empírica Entre o RacioCínio Espacial dos Estudantes de Graduação EM Carreiras Não Científicas e Seu Conhecimento Conceitual da Astronomia

    NASA Astrophysics Data System (ADS)

    Heyer, Inge; Slater, Stephanie J.; Slater, Timothy F.

    2013-12-01

    The astronomy education community has tacitly assumed that learning astronomy is a conceptual domain resting upon spatial thinking skills. As a first step to formally identify an empirical relationship, undergraduate students in a non-major introductory astronomy survey class at a mediumsized, Ph.D. granting, mid-western US university were given pre- and post-astronomy conceptual diagnostics and spatial reasoning diagnostics, Instruments used were the "Test Of Astronomy Standards" and "What Do You Know?" Using only fully matched data for analysis, our sample consisted of 86 undergraduate non-science majors. Students' normalized gains for astronomy surveys were low at .26 and .13 respectively. Students' spatial thinking was measured using an instrument designed specifically for this study. Correlations between the astronomy instruments' pre- to post-course gain scores and the spatial assessment instrument show moderate to strong relationships suggesting the relationship between spatial reasoning and astronomy ability can explain about 25% of the variation in student achievement. La comunidad de educación en astronomía ha supuesto de forma tácita que el aprendizaje de la astronomía consiste en un dominio conceptual fundamentado en el razonamiento espacial. Como un primer paso para identificar formalmente una relación empírica entre estas dos cosas, utilizamos como muestra los estudantes de graduación de carreras no científicas de un curso experimental en una universidad norteamericana del medioeste de porte mediano con programa de Doctorado em curso, en el cual estos estudiantes se sometieron a un diagnóstico de razonamiento espacial y conceptos astronómicos antes e después del mismo. Las herramientas utilizadas fueron el Test Of Astronomy Standards (TOAST) y el cuestionario What do you know? Utilizando solo los datos completamente consistentes para este análisis, nuestra muestra consistió en 86 estudantes de graduación. Las mejoras, depués de

  7. El círculo meridiano automático de San Fernando - San Juan. Sus primeros pasos en el hemisferio sur

    NASA Astrophysics Data System (ADS)

    Mallamaci, C. C.; Muiños, J. L.; Gallego, M.; Pérez, J. A.; Marmolejo, L.; Navarro, J. L.; Sedeño, J.; Vallejos, M.; Belizón, F.

    Se informa sobre el estado actual del Círculo Meridiano Automático de San Fernando-San Juan. El instrumento (Grubb-Parson, de 178mm de abertura y 2665 mm de distancia focal) es gemelo del que se encuentra en las Islas Canarias, y fue instalado durante los meses de julio y agosto de 1996 en la estación astronómica ``Dr. C.U.Cesco" (El Leoncito, Barreal), a unos 200 km de distancia de la ciudad de San Juan, merced a un Convenio de Cooperación Científica, firmado en 1994 entre el ROA (España) y el OAFA (Argentina). En la actualidad se está llevando a cabo un programa de prueba cuyos resultados preliminares muestran que el telescopio está en buenas condiciones para observar estrellas de hasta magnitud aproximada 14.5, con buenos errores de observación (<0.12" en ascensión recta y declinación).

  8. In Planta Proteomics and Proteogenomics of the Biotrophic Barley Fungal Pathogen Blumeria graminis f. sp. hordei*

    PubMed Central

    Bindschedler, Laurence V.; Burgis, Timothy A.; Mills, Davinia J. S.; Ho, Jenny T. C.; Cramer, Rainer; Spanu, Pietro D.

    2009-01-01

    To further our understanding of powdery mildew biology during infection, we undertook a systematic shotgun proteomics analysis of the obligate biotroph Blumeria graminis f. sp. hordei at different stages of development in the host. Moreover we used a proteogenomics approach to feed information into the annotation of the newly sequenced genome. We analyzed and compared the proteomes from three stages of development representing different functions during the plant-dependent vegetative life cycle of this fungus. We identified 441 proteins in ungerminated spores, 775 proteins in epiphytic sporulating hyphae, and 47 proteins from haustoria inside barley leaf epidermal cells and used the data to aid annotation of the B. graminis f. sp. hordei genome. We also compared the differences in the protein complement of these key stages. Although confirming some of the previously reported findings and models derived from the analysis of transcriptome dynamics, our results also suggest that the intracellular haustoria are subject to stress possibly as a result of the plant defense strategy, including the production of reactive oxygen species. In addition, a number of small haustorial proteins with a predicted N-terminal signal peptide for secretion were identified in infected tissues: these represent candidate effector proteins that may play a role in controlling host metabolism and immunity. PMID:19602707

  9. Wide Screening of Phage-Displayed Libraries Identifies Immune Targets in Planta

    PubMed Central

    Rioja, Cristina; Van Wees, Saskia C.; Charlton, Keith A.; Pieterse, Corné M. J.; Lorenzo, Oscar; García-Sánchez, Susana

    2013-01-01

    Microbe-Associated Molecular Patterns and virulence effectors are recognized by plants as a first step to mount a defence response against potential pathogens. This recognition involves a large family of extracellular membrane receptors and other immune proteins located in different sub-cellular compartments. We have used phage-display technology to express and select for Arabidopsis proteins able to bind bacterial pathogens. To rapidly identify microbe-bound phage, we developed a monitoring method based on microarrays. This combined strategy allowed for a genome-wide screening of plant proteins involved in pathogen perception. Two phage libraries for high-throughput selection were constructed from cDNA of plants infected with Pseudomonas aeruginosa PA14, or from combined samples of the virulent isolate DC3000 of Pseudomonas syringae pv. tomato and its avirulent variant avrRpt2. These three pathosystems represent different degrees in the specificity of plant-microbe interactions. Libraries cover up to 2×107 different plant transcripts that can be displayed as functional proteins on the surface of T7 bacteriophage. A number of these were selected in a bio-panning assay for binding to Pseudomonas cells. Among the selected clones we isolated the ethylene response factor ATERF-1, which was able to bind the three bacterial strains in competition assays. ATERF-1 was rapidly exported from the nucleus upon infiltration of either alive or heat-killed Pseudomonas. Moreover, aterf-1 mutants exhibited enhanced susceptibility to infection. These findings suggest that ATERF-1 contains a microbe-recognition domain with a role in plant defence. To identify other putative pathogen-binding proteins on a genome-wide scale, the copy number of selected-vs.-total clones was compared by hybridizing phage cDNAs with Arabidopsis microarrays. Microarray analysis revealed a set of 472 candidates with significant fold change. Within this set defence-related genes, including well-known targets of bacterial effectors, are over-represented. Other genes non-previously related to defence can be associated through this study with general or strain-specific recognition of Pseudomonas. PMID:23372747

  10. Regioselectivity of glucosylation of caffeic acid by a UDP-glucose:glucosyltransferase is maintained in planta.

    PubMed Central

    Lim, Eng-Kiat; Higgins, Gillian S; Li, Yi; Bowles, Dianna J

    2003-01-01

    Caffeic acid is a phenylpropanoid playing an important role in the pathways leading to lignin synthesis and the production of a wide variety of secondary metabolites. The compound is also an antioxidant and has potential utility as a general protectant against free radicals. Three glucosylated forms of caffeic acid are known to exist: the 3- O - and 4- O -glucosides and the glucose ester. This study describes for the first time a glucosyltransferase [UDP-glucose:glucosyltransferase (UGT)] that is specific for the 3-hydroxyl, and not the 4-hydroxyl, position of caffeic acid. The UGT sequence of Arabidopsis, UGT71C1, has been expressed as a recombinant fusion protein in Escherichia coli, purified and assayed against a range of substrates in vitro. The assay confirmed that caffeic acid as the preferred substrate when compared with other hydroxycinnamates, although UGT71C1 also exhibited substantial activity towards flavonoid substrates, known to have structural features that can be recognized by many different UGTs. The expression of UGT71C1 in transgenic Arabidopsis was driven by the constitutive cauliflower mosaic virus 35 S (CaMV35S) promoter. Nine independent transgenic lines were taken to homozygosity and characterized by Northern-blot analysis, assay of enzyme activity in leaf extracts and HPLC analysis of the glucosides. The level of expression of UGT71C1 was enhanced considerably in several lines, leading to a higher level of the corresponding enzyme activity and a higher level of caffeoyl-3- O -glucoside. The data are discussed in the context of the utility of UGTs for natural product biotransformations. PMID:12741958

  11. Angiogenic activity of latex from Euphorbia tirucalli Linnaeus 1753 (Plantae, Euphorbiaceae).

    PubMed

    Bessa, G; Melo-Reis, P R; Araújo, L A; Mrué, F; Freitas, G B; Brandão, M L; Silva Júnior, N J

    2015-08-01

    To assess the pro-angiogenic activity of Euphorbia tirucalli, commonly known as "avelós" plant, we performed a series of tests by applying an aqueous E. tirucalli latex solution (10 mg/mL) to the chorioallantoic membranes (CAMs) of 80 fertilized chicken eggs incubated in a temperature- and humidity-controlled automatic incubator. The results indicated that the aqueous latex solution increased vascular network formation compared to that with the negative control (p < 0.05) and the inhibitor control (p < 0.05). This suggests that under the experimental conditions tested, the aqueous latex solution induced an inflammatory response leading to neoangiogenesis. PMID:26465734

  12. Chrysanthemyl Diphosphate Synthase Operates in Planta as a Bifunctional Enzyme with Chrysanthemol Synthase Activity*

    PubMed Central

    Yang, Ting; Gao, Liping; Hu, Hao; Stoopen, Geert; Wang, Caiyun; Jongsma, Maarten A.

    2014-01-01

    Chrysanthemyl diphosphate synthase (CDS) is the first pathway-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1′-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate (CPP). Three proteins are known to catalyze this cyclopropanation reaction of terpene precursors. Two of them, phytoene and squalene synthase, are bifunctional enzymes with both prenyltransferase and terpene synthase activity. CDS, the other member, has been reported to perform only the prenyltransferase step. Here we show that the NDXXD catalytic motif of CDS, under the lower substrate conditions prevalent in plants, also catalyzes the next step, converting CPP into chrysanthemol by hydrolyzing the diphosphate moiety. The enzymatic hydrolysis reaction followed conventional Michaelis-Menten kinetics, with a Km value for CPP of 196 μm. For the chrysanthemol synthase activity, DMAPP competed with CPP as substrate. The DMAPP concentration required for half-maximal activity to produce chrysanthemol was ∼100 μm, and significant substrate inhibition was observed at elevated DMAPP concentrations. The N-terminal peptide of CDS was identified as a plastid-targeting peptide. Transgenic tobacco plants overexpressing CDS emitted chrysanthemol at a rate of 0.12–0.16 μg h−1 g−1 fresh weight. We propose that CDS should be renamed a chrysanthemol synthase utilizing DMAPP as substrate. PMID:25378387

  13. In planta changes in protein phosphorylation induced by the plant hormone abscisic acid

    PubMed Central

    Kline, Kelli G.; Barrett-Wilt, Gregory A.; Sussman, Michael R.

    2010-01-01

    Abscisic acid (ABA) is a hormone that controls seed dormancy and germination as well as the overall plant response to important environmental stresses such as drought. Recent studies have demonstrated that the ABA-bound receptor binds to and inhibits a class of protein phosphatases. To identify more broadly the phosphoproteins affected by this hormone in vivo, we used 14N/15N metabolic labeling to perform a quantitative untargeted mass spectrometric analysis of the Arabidopsis thaliana phosphoproteome following ABA treatment. We found that 50 different phosphopeptides had their phosphorylation state significantly altered by ABA over a treatment period lasting 5–30 min. Among these changes were increases in phosphorylation of subfamily 2 SNF1-related kinases and ABA-responsive basic leucine zipper transcription factors implicated in ABA signaling by previous in vitro studies. Furthermore, four members of the aquaporin family showed decreased phosphorylation at a carboxy-terminal serine which is predicted to cause closure of the water-transporting aquaporin gate, consistent with ABA's role in ameliorating the effect of drought. Finally, more than 20 proteins not previously known to be involved with ABA were found to have significantly altered phosphorylation levels. Many of these changes are phosphorylation decreases, indicating that an expanded model of ABA signaling, beyond simple phosphatase inhibition, may be necessary. This quantitative proteomics dataset provides a more comprehensive, albeit incomplete, view both of the protein targets whose biochemical activities are likely to be controlled by ABA and of the nature of the emerging phosphorylation and dephosphorylation cascades triggered by this hormone. PMID:20733066

  14. In planta localisation patterns of MADS domain proteins during floral development in Arabidopsis thaliana

    PubMed Central

    Urbanus, Susan L; de Folter, Stefan; Shchennikova, Anna V; Kaufmann, Kerstin; Immink, Richard GH; Angenent, Gerco C

    2009-01-01

    Background MADS domain transcription factors play important roles in various developmental processes in flowering plants. Members of this family play a prominent role in the transition to flowering and the specification of floral organ identity. Several studies reported mRNA expression patterns of the genes encoding these MADS domain proteins, however, these studies do not provide the necessary information on the temporal and spatial localisation of the proteins. We have made GREEN FLUORESCENT PROTEIN (GFP) translational fusions with the four MADS domain proteins SEPALLATA3, AGAMOUS, FRUITFULL and APETALA1 from the model plant Arabidopsis thaliana and analysed the protein localisation patterns in living plant tissues by confocal laser scanning microscopy (CLSM). Results We unravelled the protein localisation patterns of the four MADS domain proteins at a cellular and subcellular level in inflorescence and floral meristems, during development of the early flower bud stages, and during further differentiation of the floral organs. The protein localisation patterns revealed a few deviations from known mRNA expression patterns, suggesting a non-cell autonomous action of these factors or alternative control mechanisms. In addition, we observed a change in the subcellular localisation of SEPALLATA3 from a predominantly nuclear localisation to a more cytoplasmic localisation, occurring specifically during petal and stamen development. Furthermore, we show that the down-regulation of the homeodomain transcription factor WUSCHEL in ovular tissues is preceded by the occurrence of both AGAMOUS and SEPALLATA3 proteins, supporting the hypothesis that both proteins together suppress WUSCHEL expression in the ovule. Conclusion This approach provides a highly detailed in situ map of MADS domain protein presence during early and later stages of floral development. The subcellular localisation of the transcription factors in the cytoplasm, as observed at certain stages during development, points to mechanisms other than transcriptional control. Together this information is essential to understand the role of these proteins in the regulatory processes that drive floral development and leads to new hypotheses. PMID:19138429

  15. "In planta" regulation of the "Arabidopsis" Ca(2+)/H(+) antiporter CAX1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vacuolar localized Ca(2+)/H(+) exchangers such as "Arabidopsis thaliana" cation exchanger 1 (CAX1) play important roles in Ca(2+) homeostasis. When expressed in yeast, CAX1 is regulated via an N-terminal autoinhibitory domain. In yeast expression assays, a 36 amino acid N-terminal truncation of CAX1...

  16. Plant Tissue Preparation for the Detection of an Endophytic Fungus In Planta.

    PubMed

    McKinnon, Aimee C

    2016-01-01

    The identification of fungal endophytes often relies on culturing isolates from surface-sterilized plant tissue. However, molecular techniques have enabled the rapid detection and identification of targeted endophyte species, and next-generation sequencing technology provides an opportunity to obtain comprehensive information on endophytic communities, directly from plant tissue. In order to achieve accurate detection from internal tissues, surface microbes and associated deoxyribonucleic acid (DNA) must be eliminated, with particular consideration for the type of plant tissue and the efficacy of the surface sterilization procedure used. The methodology described later was developed specifically for detection of DNA from the entomopathogenic fungal endophyte Beauveria bassiana (Vuillemin) (Ascomycota: Hypocreales) in various tissues of Zea mays (L.). However, the protocol may be easily applied to other fungi and bacterial endophytes. Included is a stringent sodium hypochlorite-based surface sterilization protocol for plant material in preparation for polymerase chain reaction (PCR) to detect target DNA within plant tissue. Included are a treatment for dealing with surface DNA contamination and a novel procedure for assessing the efficacy of surface sterilization using PCR. PMID:27565499

  17. Floral Benzenoid Carboxyl Methyltransferases: From in Vitro to in Planta Function

    SciTech Connect

    Effmert,U.; Saschenbrecker, S.; Ross, J.; Negre, F.; Fraser, C.; Noel, J.; Dudareva, N.; Piechulla, B.

    2005-01-01

    Benzenoid carboxyl methyltransferases synthesize methyl esters (e.g., methyl benzoate and methyl salicylate), which are constituents of aromas and scents of many plant species and play important roles in plant communication with the surrounding environment. Within the past five years, eleven such carboxyl methyltransferases were isolated and most of them were comprehensively investigated at the biochemical, molecular and structural level. Two types of enzymes can be distinguished according to their substrate preferences: the SAMT-type enzymes isolated from Clarkia breweri, Stephanotis floribunda, Antirrhinum majus, Hoya carnosa, and Petunia hybrida, which have a higher catalytic efficiency and preference for salicylic acid, while BAMT-type enzymes from A. majus, Arabidopsis thaliana, Arabidopsis lyrata, and Nicotiana suaveolens prefer benzoic acid. The elucidation of C. breweri SAMT's three-dimensional structure allowed a detailed modelling of the active sites of the carboxyl methyltransferases and revealed that the SAM binding pocket is highly conserved among these enzymes while the methyl acceptor binding site exhibits some variability, allowing a classification into SAMT-type and BAMT-type enzymes. The analysis of expression patterns coupled with biochemical characterization showed that these carboxyl methyltransferases are involved either in floral scent biosynthesis or in plant defense responses. While the latter can be induced by biotic or abiotic stress, the genes responsible for floral scent synthesis exhibit developmental and rhythmic expression pattern. The nature of the product and efficiency of its formation in plants depend on the availability of substrates, the catalytic efficiency of the enzyme toward benzoic acid and/or salicylic acid, and the transcriptional, translational, and post-translational regulation at the enzyme level. The biochemical properties of benzenoid carboxyl methyltransferases suggest that the genes involved in plant defenses might represent the ancestor for the presently existing floral genes which during evolution gained different expression profiles and encoded enzymes with the ability to accept structurally similar substrates.

  18. Binary 2in1 Vectors Improve in Planta (Co)localization and Dynamic Protein Interaction Studies.

    PubMed

    Hecker, Andreas; Wallmeroth, Niklas; Peter, Sébastien; Blatt, Michael R; Harter, Klaus; Grefen, Christopher

    2015-07-01

    Fluorescence-based protein-protein interaction techniques are vital tools for understanding in vivo cellular functions on a mechanistic level. However, only under the condition of highly efficient (co)transformation and accumulation can techniques such as Förster resonance energy transfer (FRET) realize their potential for providing highly accurate and quantitative interaction data. FRET as a fluorescence-based method unifies several advantages, such as measuring in an in vivo environment, real-time context, and the ability to include transient interactions as well as detecting the mere proximity of proteins. Here, we introduce a novel vector set that incorporates the benefit of the recombination-based 2in1 cloning system with the latest state-of-the-art fluorescent proteins for optimal coaccumulation and FRET output studies. We demonstrate its utility across a range of methods. Merging the 2in1 cloning system with new-generation FRET fluorophore pairs allows for enhanced detection, speeds up the preparation of clones, and enables colocalization studies and the identification of meaningful protein-protein interactions in vivo. PMID:25971551

  19. Chrysanthemyl diphosphate synthase operates in planta as a bifunctional enzyme with chrysanthemol synthase activity.

    PubMed

    Yang, Ting; Gao, Liping; Hu, Hao; Stoopen, Geert; Wang, Caiyun; Jongsma, Maarten A

    2014-12-26

    Chrysanthemyl diphosphate synthase (CDS) is the first pathway-specific enzyme in the biosynthesis of pyrethrins, the most widely used plant-derived pesticide. CDS catalyzes c1'-2-3 cyclopropanation reactions of two molecules of dimethylallyl diphosphate (DMAPP) to yield chrysanthemyl diphosphate (CPP). Three proteins are known to catalyze this cyclopropanation reaction of terpene precursors. Two of them, phytoene and squalene synthase, are bifunctional enzymes with both prenyltransferase and terpene synthase activity. CDS, the other member, has been reported to perform only the prenyltransferase step. Here we show that the NDXXD catalytic motif of CDS, under the lower substrate conditions prevalent in plants, also catalyzes the next step, converting CPP into chrysanthemol by hydrolyzing the diphosphate moiety. The enzymatic hydrolysis reaction followed conventional Michaelis-Menten kinetics, with a Km value for CPP of 196 μm. For the chrysanthemol synthase activity, DMAPP competed with CPP as substrate. The DMAPP concentration required for half-maximal activity to produce chrysanthemol was ∼100 μm, and significant substrate inhibition was observed at elevated DMAPP concentrations. The N-terminal peptide of CDS was identified as a plastid-targeting peptide. Transgenic tobacco plants overexpressing CDS emitted chrysanthemol at a rate of 0.12-0.16 μg h(-1) g(-1) fresh weight. We propose that CDS should be renamed a chrysanthemol synthase utilizing DMAPP as substrate. PMID:25378387

  20. Dynamic Root Exudation of Sorgoleone and Its in Planta Mechanism of Action

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The oily droplets exuding from the root hairs of sorghum are composed of a 1:1 ratio of sorgoleone and its lipid resorcinol analog. The production and release appear to be suppressed when 15 to 20 µg/mg dry weight accumulates at the tip of the root hairs. However, more exudate is produced followin...

  1. Stable plasmid vectors for complementation of Xylella fastidiosa mutants in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current understanding of the mechanisms of Pierce’s Disease development has been significantly advanced by molecular genetic studies of the causal agent, Xylella fastidiosa (Xf). Plasmid vectors are an essential tool for studies of bacterial genetics and pathogenesis. However, most commonly used pla...

  2. Quantification of Sclerotinia homoeocarpa overwintering in planta and detection in commercial seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dollar spot is the most economically important disease of amenity turf grasses in the United States, yet little is known about the source of primary inoculum for this disease. With the exception of a few isolates from the United Kingdom, Sclerotinia homoeocarpa, the causal agent of dollar spot, does...

  3. Origin and evolution of metal P-type ATPases in Plantae (Archaeplastida)

    PubMed Central

    Hanikenne, Marc; Baurain, Denis

    2013-01-01

    Metal ATPases are a subfamily of P-type ATPases involved in the transport of metal cations across biological membranes. They all share an architecture featuring eight transmembrane domains in pairs of two and are found in prokaryotes as well as in a variety of Eukaryotes. In Arabidopsis thaliana, eight metal P-type ATPases have been described, four being specific to copper transport and four displaying a broader metal specificity, including zinc, cadmium, and possibly copper and calcium. So far, few efforts have been devoted to elucidating the origin and evolution of these proteins in Eukaryotes. In this work, we use large-scale phylogenetics to show that metal P-type ATPases form a homogenous group among P-type ATPases and that their specialization into either monovalent (Cu) or divalent (Zn, Cd…) metal transport stems from a gene duplication that took place early in the evolution of Life. Then, we demonstrate that the four subgroups of plant metal ATPases all have a different evolutionary origin and a specific taxonomic distribution, only one tracing back to the cyanobacterial progenitor of the chloroplast. Finally, we examine the subsequent evolution of these proteins in green plants and conclude that the genes thoroughly characterized in model organisms are often the result of lineage-specific gene duplications, which calls for caution when attempting to infer function from sequence similarity alone in non-model organisms. PMID:24575101

  4. Chemical compounds effective against the citrus huanglongbing bacterium 'Candidatus Liberibacter asiaticus' in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus huanglongbing (HLB) is one of the most destructive diseases of citrus worldwide, and is threatening the survival of the Floridian citrus industry. Currently, there is no established cure for this century-old and emerging disease. The new antibiotic combination of penicillin and streptomycin (...

  5. The Papaver rhoeas S determinants confer self-incompatibility to Arabidopsis thaliana in planta.

    PubMed

    Lin, Zongcheng; Eaves, Deborah J; Sanchez-Moran, Eugenio; Franklin, F Christopher H; Franklin-Tong, Vernonica E

    2015-11-01

    Self-incompatibility (SI) is a major genetically controlled system used to prevent inbreeding in higher plants. S determinants regulate allele-specific rejection of "self" pollen by the pistil. SI is an important model system for cell-to-cell recognition and signaling and could be potentially useful for first-generation (F1) hybrid breeding. To date, the transfer of S determinants has used the complementation of orthologs to "restore" SI in close relatives. We expressed the Papaver rhoeas S determinants PrsS and PrpS in Arabidopsis thaliana. This enabled pistils to reject pollen expressing cognate PrpS. Moreover, plants coexpressing cognate PrpS and PrsS exhibit robust SI. This demonstrates that PrsS and PrpS are sufficient for a functional synthetic S locus in vivo. This transfer of novel S determinants into a highly divergent species (>140 million years apart) with no orthologs suggests their potential utility in crop production. PMID:26542572

  6. Regulation and mechanism of potassium release from barley roots: an in planta 42K+ analysis.

    PubMed

    Coskun, Devrim; Britto, Dev T; Kronzucker, Herbert J

    2010-12-01

    Potassium (K(+) ) flux into plant cells is a well-characterized ion transport phenomenon. By contrast, little is known about the mechanisms and regulation of K(+) flux from the cell. Here, we present a radioisotopic analysis of K(+) fluxes from roots of intact barley (Hordeum vulgare), in the context of recent discoveries in the molecular biology and electrophysiology of this process. Plants were labelled with (42)K(+), and kinetics of its release from roots were monitored at low (0.1 mM) or high (1.0 mM) external K concentration, [K(+)](ext), and with the application of channel modulators and nutrient shifts. At 0.1 (but not 1.0) mM [K(+)], where K(+) efflux is thought to be mediated by K(+)-outward-rectifying channels, (42)K(+) efflux was inhibited by the channel blockers barium (Ba(2+)), caesium (Cs(+)), tetraethylammonium (TEA(+)), and lanthanum (La(3+)). Ammonium and nitrate (10 mM) stimulated and inhibited (42)K(+) efflux, respectively, while 10 mM [K(+)](ext) or [Rb(+) ](ext) decreased it. No evidence for the involvement of ATP-binding cassettes, nonselective cation channels, or active K(+)-efflux pumps was found. Our study provides new evidence for the thermodynamic transition between high- and low-affinity transport, from the efflux perspective, identifying the operation of channels at low [K(+)], and the cessation of transmembrane efflux at high [K(+)]. PMID:20731780

  7. In planta distribution and quantification of Asiatic strain of citrus Huanglongbing pathogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Huanglongbing is one of the most devastating diseases caused by an uncultured phloem limited bacterium, Candidatus Liberibacter spp. In this study, a combination of traditional and real-time PCR targeting the putative DNA polymerase and 16S rDNA sequence, respectively, were used to examine the distr...

  8. In planta reduction of maize seedling stalk lesions by the bacterial endophyte Bacillus mojavensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to autoinfection and alloinfection, maize is susceptible to infection by Fusarium verticillioides resulting in diseases and contamination of maize kernels with the fumonisin mycotoxins. Attempts at controlling this fungus are currently being done with biocontrol agents such as bacteria and this...

  9. Staphylococcal abscess caused by trauma with a rosebush aculeus (Plantae, Rosaceae): apropos of a case.

    PubMed

    Bernardes Filho, Fred; Alves, Andreia Oliveira; Martins, Gustavo; Sasso, Letícia Soares; Gama, Carolina Mendonça; Cenci, Gardênia Borges

    2013-01-01

    Cutaneous abscess is a localized collection of pus in the dermis and subcutaneous tissue usually caused by trauma. The authors report the case of a 30-year-old male patient, gardener, that presents an ulcerated plaque in the third right finger, caused by an aculeus plant wound. The examination of the lesion's exudate ruled out the existence of fungi and showed the presence of Staphylococcus aureus. The authors emphasize the sporotrichosis as an important differential diagnosis, especially in endemic areas, and the indication of the exudate culture is discussed. PMID:24474127

  10. Staphylococcal abscess caused by trauma with a rosebush aculeus (Plantae, Rosaceae): apropos of a case*

    PubMed Central

    Bernardes Filho, Fred; Alves, Andreia Oliveira; Martins, Gustavo; Sasso, Letícia Soares; Gama, Carolina Mendonça; Cenci, Gardênia Borges

    2013-01-01

    Cutaneous abscess is a localized collection of pus in the dermis and subcutaneous tissue usually caused by trauma. The authors report the case of a 30-year-old male patient, gardener, that presents an ulcerated plaque in the third right finger, caused by an aculeus plant wound. The examination of the lesion's exudate ruled out the existence of fungi and showed the presence of Staphylococcus aureus. The authors emphasize the sporotrichosis as an important differential diagnosis, especially in endemic areas, and the indication of the exudate culture is discussed. PMID:24474127

  11. Analysis of PLEs' Implementation under OER Design as a Productive Teaching-Learning Strategy in Higher Education. A Case Study at Universidad Nacional de Educación a Distancia

    ERIC Educational Resources Information Center

    Vázquez-Cano, Esteban; Martín-Monje, Elena; Castrillo de Larreta-Azelain, María Dolores

    2016-01-01

    This paper shows some research which analysed the didactic functionality of Personal Learning Environments (PLEs) and Open Educational Resources (OERs). They were created by students from the Master's Degree in Information and Communication Technologies applied to language teaching and processing, at Universidad Nacional de Educación a Distancia…

  12. DIMED 86: Discurso dos Media e Ensino a Distancia = Discours des Media et Enseignement a Distance = Media Speech and Distance Teaching. Papers Presented at a Seminar (21st, Algarve, Portugal, March 10-15, 1986).

    ERIC Educational Resources Information Center

    Coelho, Maria Eduarda Leal

    Presentations at this seminar on distance education focused on the different types of speech in multimedia presentations which contribute to the elaboration (simulated or substituted) of a situation involving different relationships. In addition to opening and closing remarks by Marcel de Greve and a final report by the Scientific Committee of…

  13. Sistema Planeta-Satélite. Simulación orbital y potenciales gravitatorios

    NASA Astrophysics Data System (ADS)

    Medina, C.; Carrillo, M.

    Se presenta un programa (desarrollado en Quick Basic 4.5) que simula, en tres dimensiones, el movimiento orbital de un satélite (o luna) alrededor de un planeta, al tiempo que calcula y grafica, en un plano, el potencial gravitatorio del sistema en función de la distancia al planeta. Para la simulación orbital, se emplea la matriz de transformación entre el sistema del planeta y el plano orbital. Para el cálculo y graficación del potencial se aplica un desarrollo en serie hasta el segundo orden, que da cuenta del efecto de achatamiento de los polos, en caso de que éste exista. Las longitudes de los ejes del planeta, la masa de éste y del satélite, sus tamaños aparentes, y los parámetros orbitales son introducidos por el usuario.

  14. Evaluacion entre colegas profesores (Peer Review of Teachers). ERIC Digest.

    ERIC Educational Resources Information Center

    Hertling, Elizabeth

    This digest in Spanish examines peer review, focusing on how these types of reviews can improve teacher competence. Peer review is often linked to peer assistance, which helps new and veteran teachers improve their knowledge and skills. In peer-review programs, consulting teachers conduct formal evaluations and recommend whether the participating…

  15. "Lo Ultimo": "Consejos"--"Un Dialogo Respetoso Entre Colegas"

    ERIC Educational Resources Information Center

    Vasquez, Olga A.; Flores, Belinda Bustos; Clark, Ellen Riojas

    2001-01-01

    "Los testimonios," or life stories, shared in this volume reveal that academia represents a labyrinth of challenges for aspiring and emerging Latina scholars--a story these authors know all too well. As Latina "veterana" scholars, who have traveled this arduous journey, the authors recognize that their collective efforts have…

  16. Etude de la flore bactérienne contaminant les téléphones mobiles avant et après la désinfection: comparaison entre les professionnels soignants de l'hôpital militaire d'instruction Mohammed V de Rabat et les témoins

    PubMed Central

    Uwingabiye, Jean; Moustanfii, Wafaa; Chadli, Meryem; Sekhsokh, Yassine

    2015-01-01

    Introduction L'objectif de notre travail était évaluer la contamination microbienne des téléphones mobiles utilisés par les personnels soignants des différents services de l'hôpital militaire d'instructions Mohammed V de Rabat et la comparer à celui d'une population témoin et aussi démontrer l'efficacité des solutions hydroalcoolique dans la désinfection de ces téléphones mobiles. Méthodes Il s'agit d'une étude descriptive transversale réalisée sur une période de 9 mois entre septembre 2010 et juin 2011, dans le service de bactériologie de l'hôpital militaire d'Instruction Mohammed V. Résultats L’étude bactériologique a été faite sur 240 téléphones mobiles dont 50% provenaient de personnels de sante. Le taux de contamination bactérienne de tous les téléphones mobiles était de 100%. Les cultures des bactéries isolées au niveau des téléphones mobiles du personnel médical étaient plus polymorphes que celles de la population témoin (p=0,028). Parmi 437 bactéries isolées: 223(51%) provenaient de téléphones de personnels de santé et 214(49%) de téléphones de la population témoin avec une différence qui n’était pas statistiquement significative(p>0,05) sauf pour les isolats de Staphylocoque à coagulase négative et Staphylococcus aureus. Les bactéries isolées étaient représentées par: Staphylocoque à coagulase (57,7%), Staphylococcus aureus (18,1%), Corynebacterium sp (18,8%), Bacillus sp (2,3%) et autres (2,2%). La différence entre la prévalence des bactéries isolées selon les services et les fonctions des personnels de santé n’était pas statistiquement significative (p>0,05). La désinfection des téléphones portables par la solution hydroalcoolique a réduit à 99,5% le nombre des colonies. Conclusion Ce travail montre que les téléphones portables pourraient jouer un rôle dans la transmission des infections nosocomiales et communautaires. Dans le cadre de prévention de ces risques, il faut

  17. Toxicité sérotoninergique résultant d’une interaction médicamenteuse entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine

    PubMed Central

    Charbonneau, Annie

    2013-01-01

    RÉSUMÉ Contexte : Le bleu de méthylène est employé en pratique pour diverses raisons médicales. Des données récentes ont évoqué une interaction potentielle avec les inhibiteurs de la recapture de la sérotonine, pouvant conduire à une toxicité sérotoninergique. Objectif : Décrire le risque de toxicité sérotoninergique associé à l’interaction entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine. Sources de l’information : Les publications pertinentes ont été ciblées systématiquement au moyen des moteurs de recherche MEDLINE (1946 au 21 mars 2013) et Embase (1974 à 2013, semaine 11) en utilisant les mots clés suivants : methylene blue, methylthioninium, monoamine oxidase inhibitors, serotonin reuptake inhibitors et serotonin syndrome. Aucune restriction touchant l’indication du bleu de méthylène ou la langue n’a été appliquée. Les références des publications ont également été analysées. Sélection des études et extraction des données : Dix-huit études de cas et deux séries de cas systématiques ont été sélectionnées. Aucune étude clinique aléatoire n’a encore été publiée. Synthèse des résultats : La première étude de cas à avoir soupçonné une interaction entre le bleu de méthylène et les inhibiteurs de la recapture de la sérotonine est parue en 2003. Dix-sept autres études de cas décrivant le même type d’interaction ont par la suite été rapportées. Les deux séries de cas ont regroupé les données de quelques 325 parathyroïdectomies où le bleu de méthylène avait été employé comme agent colorant. Les 17 patients qui ont présenté une toxicité du système nerveux central prenaient tous en période préopératoire des inhibiteurs de recapture de la sérotonine. Conclusion : Lorsqu’il est administré en concomitance avec des inhibiteurs de recapture de la sérotonine, le bleu de méthylène peut conduire à une toxicité sérotoninergique à une dose aussi

  18. [In Process Citation].

    PubMed

    Daponte Codina, A; Bolivar Muñoz, J; Sánchez-Cantalejo, E; Mateo-Rodríguez, I; Babio, G; Romo-Avilés, N; Rosell-Ortiz, F; Grupo de Estudio de Género Y Enfermedades Cardiovasculares, G

    2016-01-01

     RESUMEN              Fundamento. Identificar factores asociados a la demora prehospitalaria en personas que han tenido un síndrome coronario agudo             Método. Se estudiaron mediante encuesta pacientes ingresados por síndrome coronario agudo en los 33 hospitales públicos andaluces, obteniéndose información sobre diferentes tipos de variables: socio-demográficas, contextuales, clínicas, percepción, actuaciones, y transporte. Se aplicaron modelos de regresión logística multivariante para calcular las odds ratio para la demora.             Resultados. De los 1.416 pacientes en total, más de la mitad tuvieron una demora superior a la hora. Se asocia a la distancia al hospital y al medio de transporte: cuando el evento ocurre en la misma ciudad del hospital, utilizar medios propios aumenta la demora, odds ratio= 1,51 (1,02-2,23);  si la distancia es entre 1-25 kilómetros, no hay una diferencia entre medios propios y ambulancia, odds ratio = 1,41 y odds ratio = 1,43 respectivamente; y cuando supera los25 kilómetros la ambulancia implica mayor demora, odds ratio = 3,13 y odds ratio = 2,20 respectivamente. Además, la sintomatología típica reduce la demora entre los hombres, pero la aumenta entre las mujeres. Asimismo, no darle importancia, esperar a la resolución de los síntomas, buscar atención sanitaria diferente a urgencias hospitalarias o al 061, tener antecedentes, encontrarse fuera de la vivienda habitual, y tener ingresos menores de 1.500 euros aumentan la demora. Tener síntomas respiratorios la reduce.             Conclusiones. La demora prehospitalaria no se ajusta a las recomendaciones sanitarias, asociándose al  entorno físico y social, a factores clínicos, y de percepción y actitudinales de los sujetos.              Palabras clave. Síndrome coronario agudo. Demora prehospitalaria. Género. Servicios de emergencias sanitarias. Desigualdades. PMID:27125609

  19. Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta.

    PubMed

    Hu, Sin-Fen; Huang, Yu-Hsin; Lin, Chan-Pin; Liu, Li-Yu Daisy; Hong, Syuan-Fei; Yang, Chiao-Yin; Lo, Hsiao-Feng; Tseng, Ting-Yu; Chen, Wei-Yao; Lin, Shih-Shun

    2015-01-01

    PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches'-broom (AYWB) phytoplasma and Peanut witches'-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies. PMID:26076458

  20. A RAPID INFECTION ASSAY FOR ARMILLARIA AND REAL-TIME PCR QUANTITATION OF THE FUNGAL BIOMASS IN PLANTA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Slow and unreliable infection in the greenhouse has been a barrier to research on Armillaria root disease. The existing infection assay takes 7-18 months for detectable infection, during which time the inoculum often dies, resulting in unequal challenge among plants. As symptom expression and mort...

  1. Remote sensing of gene expression in Planta: transgenic plants as monitors of exogenous stress perception in extraterrestrial environments

    NASA Technical Reports Server (NTRS)

    Manak, Michael S.; Paul, Anna-Lisa; Sehnke, Paul C.; Ferl, Robert J.

    2002-01-01

    Transgenic arabidopsis plants containing the alcohol dehydrogenase (Adh) gene promoter fused to the green fluorescent protein (GFP) reporter gene were developed as biological sensors for monitoring physiological responses to unique environments. Plants were monitored in vivo during exposure to hypoxia, high salt, cold, and abcissic acid in experiments designed to characterize the utility and responses of the Adh/GFP biosensors. Plants in the presence of environmental stimuli that induced the Adh promoter responded by expressing GFP, which in turn generated a detectable fluorescent signal. The GFP signal degraded when the inducing stimulus was removed. Digital imaging of the Adh/GFP plants exposed to each of the exogenous stresses demonstrated that the stress-induced gene expression could be followed in real time. The experimental results established the feasibility of using a digital monitoring system for collecting gene expression data in real time from Transgenic Arabidopsis Gene Expression System (TAGES) biosensor plants during space exploration experiments.

  2. Inhibitory effect of Xenorhabdus nematophila TB on plant pathogens Phytophthora capsici and Botrytis cinerea in vitro and in planta

    PubMed Central

    Fang, Xiangling; Zhang, Manrang; Tang, Qian; Wang, Yonghong; Zhang, Xing

    2014-01-01

    Entomopathogenic bacteria Xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. This study evaluated the inhibitory effect of X. nematophila TB culture on plant pathogens Botrytis cinerea and Phytophthora capsici. The cell-free filtrate of TB culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. The methanol-extracted bioactive compounds (methanol extract) of TB culture also had strong inhibitory effects on mycelial growth and spore germinations of both pathogens. The methanol extract (1000 μg/mL) and cell-free filtrate both showed strong therapeutic and protective effects (>70%) on grey mold both in detached tomato fruits and plants, and leaf scorch in pepper plants. This study demonstrates X. nematophila TB produces antimicrobial metabolites of strong activity on plant pathogens, with great potential for controlling tomato grey mold and pepper leaf scorch and being used in integrated disease control to reduce chemical application. PMID:24599183

  3. In planta production of the highly potent resveratrol analogue pterostilbene via stilbene synthase and O-methyltransferase co-expression

    SciTech Connect

    Rimando A. M.; Liu C.; Pan, Z.; Polashock, J. J.; Dayan, F. E., Mizuno, C. S.; Snook, M. E.; Baerson, S. R.

    2012-04-01

    Resveratrol and related stilbenes are thought to play important roles in defence responses in several plant species and have also generated considerable interest as nutraceuticals owing to their diverse health-promoting properties. Pterostilbene, a 3,5-dimethylether derivative of resveratrol, possesses properties similar to its parent compound and, additionally, exhibits significantly higher fungicidal activity in vitro and superior pharmacokinetic properties in vivo. Recombinant enzyme studies carried out using a previously characterized O-methyltransferase sequence from Sorghum bicolor (SbOMT3) demonstrated its ability to catalyse the A ring-specific 3,5-bis-O-methylation of resveratrol, yielding pterostilbene. A binary vector was constructed for the constitutive co-expression of SbOMT3 with a stilbene synthase sequence from peanut (AhSTS3) and used for the generation of stably transformed tobacco and Arabidopsis plants, resulting in the accumulation of pterostilbene in both species. A reduced floral pigmentation phenotype observed in multiple tobacco transformants was further investigated by reversed-phase HPLC analysis, revealing substantial decreases in both dihydroquercetin-derived flavonoids and phenylpropanoid-conjugated polyamines in pterostilbene-producing SbOMT3/AhSTS3 events. These results demonstrate the potential utility of this strategy for the generation of pterostilbene-producing crops and also underscore the need for the development of additional approaches for minimizing concomitant reductions in key phenylpropanoid-derived metabolites.

  4. Production of recombinant single chain antibodies (scFv) in vegetatively reproductive Kalanchoe pinnata by in planta transformation.

    PubMed

    Jung, Yuchul; Rhee, Yong; Auh, Chung-Kyoon; Shim, Hyekyung; Choi, Jung-Jin; Kwon, Suk-Tae; Yang, Joo-Sung; Kim, Donggiun; Kwon, Myung-Hee; Kim, Yong-Sung; Lee, Sukchan

    2009-10-01

    We developed an asexual reproductive plant, Kalanchoe pinnata, as a new bioreactor for plant-based molecular farming using a newly developed transformation method. Leaf crenate margins were pin-pricked to infect the plant with the Agrobacterium strain LBA4404 and vacuum infiltration was also applied to introduce the target gene into the plants. Subsequently, the young mother leaf produced new clones at the leaf crenate margins without the need for time- and labor-consuming tissue culture procedures. The average transformation rates were approximately 77 and 84% for pin-prickling and vacuum-infiltration methods, respectively. To functionally characterize an introduced target protein, a nucleic acid hydrolyzing recombinant 3D8 scFv was selected and the plant based 3D8 scFv proteins were purified and analyzed. Based on abzyme analysis, the purified protein expressed with this system had catalytic activity and exhibited all of properties of the protein produced in an E. coli system. This result suggested that vegetatively reproductive K. pinnata can be a novel and potent bioreactor for bio-pharmaceutical proteins. PMID:19688214

  5. Establishing and fine-tuning an in planta system for potato zebra chip disease research in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have acquired an APHIS-PPQ permit to work on “Candidatus Liberibacter solanacearum” at the USDA-ARS San Joaquin Valley Agricultural Sciences Center in Parlier, California. “Ca. L. solanacearum”, associated with Zebra chip disease (ZCD) of potato. This bacterium is currently unculturable in vitro....

  6. Production and characterization of in planta transiently produced polygalacturanase from Aspergillus niger and its fusions with hydrophobin or ELP tags

    PubMed Central

    2014-01-01

    Background Pectinases play an important role in plant cell wall deconstruction and have potential in diverse industries such as food, wine, animal feed, textile, paper, fuel, and others. The demand for such enzymes is increasing exponentially, as are the efforts to improve their production and to implement their use in several industrial processes. The goal of this study was to examine the potential of producing polygalacturonase I from Aspergillus niger in plants and to investigate the effects of subcellular compartmentalization and protein fusions on its accumulation and activity. Results Polygalacturonase I from Aspergillus niger (AnPGI) was transiently produced in Nicotiana benthamiana by targeting it to five different cellular compartments: apoplast, endoplasmic reticulum (ER), vacuole, chloroplast and cytosol. Accumulation levels of 2.5%, 3.0%, and 1.9% of total soluble protein (TSP) were observed in the apoplast, ER, and vacuole, respectively, and specific activity was significantly higher in vacuole-targeted AnPGI compared to the same enzyme targeted to the ER or apoplast. No accumulation was found for AnPGI when targeted to the chloroplast or cytosol. Analysis of AnPGI fused with elastin-like polypeptide (ELP) revealed a significant increase in the protein accumulation level, especially when targeted to the vacuole where the protein doubles its accumulation to 3.6% of TSP, while the hydrophobin (HFBI) fusion impaired AnPGI accumulation and both tags impaired activity, albeit to different extents. The recombinant protein showed activity against polygalacturonic acid with optimum conditions at pH 5.0 and temperature from 30 to 50°C, depending on its fusion. In vivo analysis of reducing sugar content revealed a higher release of reducing sugars in plant tissue expressing recombinant AnPGI compared to wild type N. benthamiana leaves. Conclusion Our results demonstrate that subcellular compartmentalization of enzymes has an impact on both the target protein accumulation and its activity, especially in the case of proteins that undergo post-translational modifications, and should be taken into consideration when protein production strategies are designed. Using plants to produce heterologous enzymes for the degradation of a key component of the plant cell wall could reduce the cost of biomass pretreatment for the production of cellulosic biofuels. PMID:24970673

  7. In planta production of the highly potent resveratrol analogue pterostilbene via stilbene synthase and O-methyltransferase co-expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stilbenoid phytoalexins such as resveratrol, play an important defense role in several plant species against pathogens such as Botrytis cinerea. In addition to their antimicrobial properties, resveratrol and related stilbenes have also generated considerable interest as nutraceuticals, due to their...

  8. An in planta-expressed polyketide synthase produces (R)-mellein in the wheat pathogen Parastagonospora nodorum.

    PubMed

    Chooi, Yit-Heng; Krill, Christian; Barrow, Russell A; Chen, Shasha; Trengove, Robert; Oliver, Richard P; Solomon, Peter S

    2015-01-01

    Parastagonospora nodorum is a pathogen of wheat that affects yields globally. Previous transcriptional analysis identified a partially reducing polyketide synthase (PR-PKS) gene, SNOG_00477 (SN477), in P. nodorum that is highly upregulated during infection of wheat leaves. Disruption of the corresponding SN477 gene resulted in the loss of production of two compounds, which we identified as (R)-mellein and (R)-O-methylmellein. Using a Saccharomyces cerevisiae yeast heterologous expression system, we successfully demonstrated that SN477 is the only enzyme required for the production of (R)-mellein. This is the first identification of a fungal PKS that is responsible for the synthesis of (R)-mellein. The P. nodorum ΔSN477 mutant did not show any significant difference from the wild-type strain in its virulence against wheat. However, (R)-mellein at 200 μg/ml inhibited the germination of wheat (Triticum aestivum) and barrel medic (Medicago truncatula) seeds. Comparative sequence analysis identified the presence of mellein synthase (MLNS) homologues in several Dothideomycetes and two sodariomycete genera. Phylogenetic analysis suggests that the MLNSs in fungi and bacteria evolved convergently from fungal and bacterial 6-methylsalicylic acid synthases. PMID:25326302

  9. Inhibitory effect of Xenorhabdus nematophila TB on plant pathogens Phytophthora capsici and Botrytis cinerea in vitro and in planta.

    PubMed

    Fang, Xiangling; Zhang, Manrang; Tang, Qian; Wang, Yonghong; Zhang, Xing

    2014-01-01

    Entomopathogenic bacteria Xenorhabdus spp. produce secondary metabolites with potential antimicrobial activity for use in agricultural productions. This study evaluated the inhibitory effect of X. nematophila TB culture on plant pathogens Botrytis cinerea and Phytophthora capsici. The cell-free filtrate of TB culture showed strong inhibitory effects (>90%) on mycelial growth of both pathogens. The methanol-extracted bioactive compounds (methanol extract) of TB culture also had strong inhibitory effects on mycelial growth and spore germinations of both pathogens. The methanol extract (1000 μg/mL) and cell-free filtrate both showed strong therapeutic and protective effects (>70%) on grey mold both in detached tomato fruits and plants, and leaf scorch in pepper plants. This study demonstrates X. nematophila TB produces antimicrobial metabolites of strong activity on plant pathogens, with great potential for controlling tomato grey mold and pepper leaf scorch and being used in integrated disease control to reduce chemical application. PMID:24599183

  10. Binary 2in1 Vectors Improve in Planta (Co)localization and Dynamic Protein Interaction Studies1[OPEN

    PubMed Central

    Hecker, Andreas; Wallmeroth, Niklas; Peter, Sébastien; Blatt, Michael R.

    2015-01-01

    Fluorescence-based protein-protein interaction techniques are vital tools for understanding in vivo cellular functions on a mechanistic level. However, only under the condition of highly efficient (co)transformation and accumulation can techniques such as Förster resonance energy transfer (FRET) realize their potential for providing highly accurate and quantitative interaction data. FRET as a fluorescence-based method unifies several advantages, such as measuring in an in vivo environment, real-time context, and the ability to include transient interactions as well as detecting the mere proximity of proteins. Here, we introduce a novel vector set that incorporates the benefit of the recombination-based 2in1 cloning system with the latest state-of-the-art fluorescent proteins for optimal coaccumulation and FRET output studies. We demonstrate its utility across a range of methods. Merging the 2in1 cloning system with new-generation FRET fluorophore pairs allows for enhanced detection, speeds up the preparation of clones, and enables colocalization studies and the identification of meaningful protein-protein interactions in vivo. PMID:25971551

  11. Phytohormonal networks promote differentiation of fiber initials on pre-anthesis cotton ovules grown in vitro and in planta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The number of cotton (Gossypium sp.) ovule epidermal cells differentiating into fiber initials is an important factor affecting cotton yield and fiber quality. Despite extensive efforts in determining the molecular mechanisms regulating fiber initial differentiation, only a few genes responsible for...

  12. In planta mechanism of action of leptospermone: impact of its physico-chemical properties on uptake, translocation, and metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leptospermone is a natural ß-triketone that specifically inhibits the enzyme p-hydrophyphenylpyruvate dioxygenase, the same molecular target site as that of the commercial herbicide mesotrione. The ß-triketone-rich essential oil of Leptospermum scoparium has both preemergence or postemergence herbi...

  13. In planta sequential hydroxylation and glycosylation of a fungal phytotoxin: Avoiding cell death and overcoming the fungal invader

    PubMed Central

    Pedras, M. S. C.; Zaharia, I. L.; Gai, Y.; Zhou, Y.; Ward, D. E.

    2001-01-01

    To facilitate plant colonization, some pathogenic fungi produce phytotoxic metabolites that damage tissues; plants may be resistant to a particular pathogen if they produce an enzyme(s) that catalyzes detoxification of this metabolite(s). Alternaria blackspot is one of the most damaging and significant fungal diseases of brassica crops, with no source of resistance known within the Brassica species. Destruxin B is the major phytotoxin produced by the blackspot-causing fungus, Alternaria brassicae (Berkley) Saccardo. We have established that a blackspot-resistant species (Sinapis alba) metabolized 14C-labeled destruxin B to a less toxic product substantially faster than any of the susceptible species. The first metabolite, hydroxydestruxin B (14C-labeled), was further biotransformed to the β-d-glucosyl derivative at a slower rate. The structures of hydroxydestruxin B and β-d-glucosyl hydroxydestruxin B were deduced from their spectroscopic data [NMR, high resolution (HR)-MS, Fourier transform infrared (FTIR)] and confirmed by total chemical synthesis. Although these hydroxylation and glucosylation reactions occurred in both resistant (S. alba) and susceptible (Brassica napus, Brassica juncea, and Brassica rapa) species, hydroxylation was the rate limiting step in the susceptible species, whereas glucosylation was the rate limiting step in the resistant species. Remarkably, it was observed that the hydroxydestruxin B induced the biosynthesis of phytoalexins in blackspot-resistant species but not in susceptible species. This appears to be a unique example of phytotoxin detoxification and simultaneous phytoalexin elicitation by the detoxification product. Our studies suggest that S. alba can overcome the fungal invader through detoxification of destruxin B coupled with production of phytoalexins. PMID:11149945

  14. In planta detection of Xanthomonas axonopodis pv. commiphorae using fyuA and rpoD genes.

    PubMed

    Samanta, Jatindra Nath; Mandal, Kunal

    2013-06-01

    Guggal is tapped for extraction of medicinally important oleo-gum-resin (guggul) by inoculating the stem bark with natural gum suspension containing pathogenic bacterium Xanthomonas axonopodis pv. commiphorae (Xac). The tree dies in the process. In absence of any specific medium for isolation of Xac, it is difficult to assess spread of the pathogen within the plant. A PCR based molecular detection technique usingfyuA and rpoD gene specific primers is described here. The primers amplified products only from Xac and not from host tissues or common saprophytes. The method was sensitive enough to produce positive signals for up to 4.4 bacterial cells or 2 pg target DNA per reaction mixture. However, PCR inhibitors present in plant tissues drastically reduced the limit of detection. A simple overnight incubation of surface sterilised plant tissues in nutrient medium was introduced to increase pathogen titre and to overcome this problem. This technique was successfully used to measure spread of Xac in plant tissues away from the site of inoculation. The pathogen showed preference for acropetal movement and did not spread to 7-8 cm below the site of inoculation till 15 days after inoculation. This suggests possibility to manage the disease through plant surgery. PMID:23926696

  15. Health risk assessment of air emissions from a municipal solid waste incineration plant--a case study.

    PubMed

    Cangialosi, Federico; Intini, Gianluca; Liberti, Lorenzo; Notarnicola, Michele; Stellacci, Paolo

    2008-01-01

    A health risk assessment of long-term emissions of carcinogenic and non-carcinogenic air pollutants has been carried out for the municipal solid waste incinerator (MSWI) of the city of Taranto, Italy. Ground level air concentrations and soil deposition of carcinogenic (Polychlorinated Dibenzo-p-Dioxins/Furans and Cd) and non-carcinogenic (Pb and Hg) pollutants have been estimated using a well documented atmospheric dispersion model. Health risk values for air inhalation, dermal contact, soil and food ingestion have been calculated based on a combination of these concentrations and a matrix of environmental exposure factors. Exposure of the surrounding population has been addressed for different release scenarios based on four pollutants, four exposure pathways and two receptor groups (children and adults). Spatial risk distribution and cancer excess cases projected from plant emissions have been compared with background mortality records. Estimated results based on the MSWI emissions show: (1) individual risks well below maximum acceptable levels, (2) very small incremental cancer risk compared with background level. PMID:17611096

  16. An In Planta-Expressed Polyketide Synthase Produces (R)-Mellein in the Wheat Pathogen Parastagonospora nodorum

    PubMed Central

    Krill, Christian; Barrow, Russell A.; Chen, Shasha; Trengove, Robert; Oliver, Richard P.; Solomon, Peter S.

    2014-01-01

    Parastagonospora nodorum is a pathogen of wheat that affects yields globally. Previous transcriptional analysis identified a partially reducing polyketide synthase (PR-PKS) gene, SNOG_00477 (SN477), in P. nodorum that is highly upregulated during infection of wheat leaves. Disruption of the corresponding SN477 gene resulted in the loss of production of two compounds, which we identified as (R)-mellein and (R)-O-methylmellein. Using a Saccharomyces cerevisiae yeast heterologous expression system, we successfully demonstrated that SN477 is the only enzyme required for the production of (R)-mellein. This is the first identification of a fungal PKS that is responsible for the synthesis of (R)-mellein. The P. nodorum ΔSN477 mutant did not show any significant difference from the wild-type strain in its virulence against wheat. However, (R)-mellein at 200 μg/ml inhibited the germination of wheat (Triticum aestivum) and barrel medic (Medicago truncatula) seeds. Comparative sequence analysis identified the presence of mellein synthase (MLNS) homologues in several Dothideomycetes and two sodariomycete genera. Phylogenetic analysis suggests that the MLNSs in fungi and bacteria evolved convergently from fungal and bacterial 6-methylsalicylic acid synthases. PMID:25326302

  17. Development of a Mild Viral Expression System for Gain-Of-Function Study of Phytoplasma Effector In Planta

    PubMed Central

    Liu, Li-Yu Daisy; Hong, Syuan-Fei; Yang, Chiao-Yin; Lo, Hsiao-Feng; Tseng, Ting-Yu; Chen, Wei-Yao; Lin, Shih-Shun

    2015-01-01

    PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches’-broom (AYWB) phytoplasma and Peanut witches’-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies. PMID:26076458

  18. A visual identification key utilizing both gestalt and analytic approaches to identification of Carices present in North America (Plantae, Cyperaceae)

    PubMed Central

    2013-01-01

    Abstract Images are a critical part of the identification process because they enable direct, immediate and relatively unmediated comparisons between a specimen being identified and one or more reference specimens. The Carices Interactive Visual Identification Key (CIVIK) is a novel tool for identification of North American Carex species, the largest vascular plant genus in North America, and two less numerous closely-related genera, Cymophyllus and Kobresia. CIVIK incorporates 1288 high-resolution tiled image sets that allow users to zoom in to view minute structures that are crucial at times for identification in these genera. Morphological data are derived from the earlier Carex Interactive Identification Key (CIIK) which in turn used data from the Flora of North America treatments. In this new iteration, images can be viewed in a grid or histogram format, allowing multiple representations of data. In both formats the images are fully zoomable. PMID:24723777

  19. [Not Available].

    PubMed

    Villa-González, Emilio; Rodríguez-López, Carlos; Barranco-Ruiz, Yaira; Cabezas-Arévalo, Luis Fabián; Chillón, Palma

    2016-01-01

    Objetivo: analizar la concordancia de dos métodos de medición (Google MapsTM vs. Sistema de Información Geográfica) para la determinación de la distancia desde el domicilio familiar hasta el colegio.Métodos: un total de 542 escolares de entre 8-11 años de edad (media = 9,36 ± 0,6) del sur de España participaron en el estudio, facilitando la dirección de su domicilio familiar. La distancia desde el domicilio familiar al colegio se calculó mediante la utilización de dos programas diferentes:Google MapsTM y Sistema de Información Geográfica (GIS) en ruta y en línea recta. La asociación entre ambos métodos fue analizada utilizando la correlación de Spearman y el grado de acuerdo a través del coeficiente de correlación intraclase (ICC), así como el método Bland Altman.Resultados: la correlación entre ambos métodos de medición propuestos fue muy significativa (r = 0,966, p < 0,001; r = 0,984, p < 0,001; y r = 0,954, p < 0,001, respectivamente), y la concordancia fue excelente (ICC = 0,96, p < 0,001; ICC = 0,92, p < 0,001; ICC = 0,97, p < 0,001).Conclusiones: los métodos de medición estudiados podrían ser utilizados en función de las necesidades de la investigación, al presentar ambos una alta concordancia. Sin embargo, se recomienda la utilización del Sistema de Información Geográfica en ruta si se cuenta con medios yfinanciación, por tratarse de un método constatado en fiabilidad y validez. PMID:27513510

  20. Courtship behavior of different wild strains of Ceratitis Capitata (Diptera: Tephritidae)

    SciTech Connect

    Briceno, D.; Eberhard, W.; Vilardi, J.; Cayol, J.-P.; Shelly, T.

    2007-03-15

    This study documents differences in the courtship behavior of wild strains of Ceratitis capitata (Wiedemann) from Madeira (Portugal), Hawaii (U.S.A.), Costa Rica, and Patagonia (Argentina). Some traits showed large variations and others substantial overlaps. The angle at which the male faced toward the female at the moment of transition from continuous wing vibration and intermittent buzzing changed very little during the course of courtship in all strains, but males from Madeira tended to face more directly toward the female than other males. Females tended to look more, and more directly, toward the males as courtship progressed in all strains. The distance between male and female tended to decrease as courtship proceeded in all strains, but the distances at which males initiated continuous vibration, intermittent buzzing, and jumped onto the female were relatively less variable between strains, except for the strain from Costa Rica. Flies of Madeira courted for longer and the male moved his head and buzzed his wings longer than the other strains. (author) [Spanish] Este estudio documenta diferencias en el comportamiento de cortejo de cepas silvestres de Ceratitis capitata (Wied.) provenientes de Madeira (Portugal), Hawaii (Estados Unidos de Norte America), Costa Rica y Patagonia (Argentina). Algunas caracteristicas mostraron grandes variaciones y traslape substancial. Los angulos a los cuales los machos miraron hacia las hembras cambiaron muy poco en el momento de la transicion de la vibracion continua al zumbido intermitente durante el curso del cortejo en todo las cepas, pero los machos de Madeira tendieron a enfrentar mas directamente a la hembra que otros machos. Los angulos de las hembras disminuyeron claramente durante el cortejo en todas las cepas. La distancia entre el macho y la hembra tendio a disminuir conforme el cortejo continuaba en todas las cepas, pero las distancias a las cuales los machos iniciaron la vibracion continua, el zumbido intermitente

  1. Overview of Spanish and Latin American Distance Higher Education.

    ERIC Educational Resources Information Center

    Garcia Garrido, Jose Luis

    1991-01-01

    Provides a brief overview of Spanish and Latin American distance education programs for higher education and describes the three most important institutions: (1) the Spanish UNED (Universidad Nacional de Educacion a Distancia); (2) the Costa Rican UNED (Universidad Estatal a Distancia); and (3) the Venezuelan UNA (Universidad Nacional Abierta).…

  2. Teaching Reading Comprehension in English in a Distance Web-Based Course: New Roles for Teachers (La enseñanza de la comprensión de lectura en inglés en un curso a distancia en la red: nuevos roles para los docentes)

    ERIC Educational Resources Information Center

    Muñoz Marín, Jorge Hugo; González Moncada, Adriana

    2010-01-01

    Distance web-based learning is a popular strategy in ELT teaching in Colombia. Despite of the growth of experiences, there are very few studies regarding teachers' participation in these courses. This paper reports preliminary findings of an on-going study aiming at exploring the roles that a teach er plays in an EFL reading comprehension…

  3. Motivation Conditions in a Foreign Language Reading Comprehension Course Offering Both a Web-Based Modality and a Face-to-Face Modality (Las condiciones de motivación en un curso de comprensión de lectura en lengua extranjera (LE) ofrecido tanto en la modalidad presencial como en la modalidad a distancia en la web)

    ERIC Educational Resources Information Center

    Lopera Medina, Sergio

    2014-01-01

    Motivation plays an important in role in education. Based on the ten macro-strategies proposed by Dörnyei and Csizér (1998), this article analyzes the motivation conditions in a foreign language reading comprehension course using both a web-based modality and a face-to-face modality. A case study was implemented as the primary research method, and…

  4. Velocidades radiales en Collinder 121

    NASA Astrophysics Data System (ADS)

    Arnal, M.; Morrell, N.

    Se han llevado a cabo observaciones espectroscópicas de unas treinta estrellas que son posibles miembros del cúmulo abierto Collinder 121. Las mismas fueron realizadas con el telescopio de 2.15m del Complejo Astronómico El Leoncito (CASLEO). El análisis de las velocidades radiales derivadas del material obtenido, confirma la realidad de Collinder 121, al menos desde el punto de vista cinemático. La velocidad radial baricentral (LSR) del cúmulo es de +17 ± 3 km.s-1. Esta velocidad coincide, dentro de los errores, con la velocidad radial (LSR) de la nebulosa anillo S308, la cual es de ~20 ± 10 km.s-1. Como S308 se encuentra físicamente asociada a la estrella Wolf-Rayet HD~50896, es muy probable que esta última sea un miembro de Collinder 121. Desde un punto de vista cinemático, la supergigante roja HD~50877 (K3Iab) también pertenecería a Collinder 121. Basándonos en la pertenencia de HD~50896 a Collinder 121, y en la interacción encontrada entre el viento de esta estrella y el medio interestelar circundante a la misma, se estima para este cúmulo una distancia del orden de 1 kpc.

  5. Apoyo a Estudios Geodinamicos con GPS en Guatemala

    NASA Astrophysics Data System (ADS)

    Robles, V. R.

    2013-05-01

    El Instituto Geografico Nacional de Guatemala implemento 17 estaciones GNSS en el año 2009, como un proyecto de credito mixto de donacion de equipamiento del Gobierno de Suiza, el cual, este equipamiento de estaciones CORS GNSS es un sistema de recepción y transmisión de datos crudos GPS RInex que utiliza la tecnologia Spider Web de Leica, asi mismo este sistema esta sirviendo para el espablecimiento de un marco geodesico nacional de coordenadas geodesicas oficiales, el cual se calculan u obtienen las velocidades en tiempos temporales programados de las 17 Estaciones CORS. La infraestructura del marco geodesico de Guatemala esta sirviendo de base para las aplicaciones de estudios geodinamicos como el monitoreo de del desplazamiento de las placas tectonicas por medio de un estudio que se inicio en el año de 1999, llamado medicion con GPS el sistema de Fallas de los rios Polochic Motagua de Guatemala, tambien para un estudio que se implemento para deformación de corteza terrestre local en un Volcan Activo de Guatemala llamado Pacaya. Para el estudio de medicion con GPS en el sistema de falla de los Rios del polochic Motagua se implementaron 16 puntos para medir con GPS de dos frecuencias en el año de 1999, el cual, tres puntos son estaciones geodesicas CORS IGS llamados GUAT, ELEN y HUEH, despues en el año de 2003 se hizo otra medicion en un total de 20 puntos, que permitió calcular las velocidades de desplazamieinto de los puntos en mención, usando como referencia el modelo NUVEL 1A de DeMets de la placa de Norteamerica. Este estudio fue en cooperación internacional por la universidad de Nice de Francia y el IGNde Francia. Para el estudio del monitoreo con GPS del volcan activo de Guatemala, se implementaron cuatro puntos al rededor del volcan, el cual, se realizan cuatro mediciones al año, que permiten determinar axialmente la distancias entre los puntos, y rebisar estadisticamente cual es el comportamiento de las distancias en funcion del tiempo, si

  6. Development and Use of a Reverse Transcription-PCR Assay To Study Expression of Tri5 by Fusarium Species In Vitro and In Planta

    PubMed Central

    Doohan, F. M.; Weston, G.; Rezanoor, H. N.; Parry, D. W.; Nicholson, P.

    1999-01-01

    The Tri5 gene encodes trichodiene synthase, which catalyzes the first reaction in the trichothecene biosynthetic pathway. In vitro, a direct relationship was observed between Tri5 expression and the increase in deoxynivalenol production over time. We developed a reverse transcription (RT)-PCR assay to quantify Tri5 gene expression in trichothecene-producing strains of Fusarium species. We observed an increase in Tri5 expression following treatment of Fusarium culmorum with fungicides, and we also observed an inverse relationship between Tri5 expression and biomass, as measured by β-d-glucuronidase activity, during colonization of wheat (cv. Avalon) seedlings by F. culmorum. RT-PCR analysis also showed that for ears of wheat cv. Avalon inoculated with F. culmorum, there were different levels of Tri5 expression in grain and chaff at later growth stages. We used the Tri5-specific primers to develop a PCR assay to detect trichothecene-producing Fusarium species in infected plant material. PMID:10473385

  7. Species-specific ITS primers for the identification of Picoa juniperi and Picoa lefebvrei and using nested-PCR for detection of P. juniperi in planta.

    PubMed

    Jamali, Samad; Banihashemi, Zia

    2013-10-01

    Desert truffles, hypogeous Pezizales (Ascomycota), are difficult to identify due to evolutionary convergence of morphological characters among taxa that share a similar habitat and mode of spore dispersal. Also, during their symbiotic phase, these are barely distinguishable morphologically, and molecular probes are needed for their identification. We have developed a PCR-based method for the identification of Picoa juniperi and Picoa lefebvrei based on internal transcribed spacers of rDNA. Two PCR primers specific for P. lefebvrei (FLE/RLE) and two specific for P. juniperi (FJU/RJU) were designed. A collection of samples from different geographical areas representing diversity of these species were examined for unique regions of internal transcribed spacers 1, 2 and 5.8S gene of rDNA (ITS) compared to other closely related species. Annealing temperatures and extension times were optimized for each set of primers for maximum specificity and efficiency. They proved to be efficient to specifically detect the presence of P. juniperi and P. lefebvrei by PCR and neither set amplified purified DNA from other truffle species as well as some ascomycetous fungi. The partial small subunit of ribosomal DNA genes of P. juniperi were amplified with the genomic DNA extracted from Helianthemum ledifolium var. ledifolium roots by nested polymerase chain reaction (PCR) using the universal fungal primer pair ITS1/ITS4 and specific primer pair FTC/RTC, which was designed based on internal transcribed spacer 1, 2 and 5.8S gene of rDNA sequences of P juniperi. The nested-PCR was sensitive enough to re-amplify the direct-PCR product, resulting in a DNA fragment of 426 bp. The efficacy of nested-PCR showed that it could re-amplify the direct-PCR product and detect 200 fg genomic DNA. PMID:24065525

  8. The Pratylenchus penetrans Transcriptome as a Source for the Development of Alternative Control Strategies: Mining for Putative Genes Involved in Parasitism and Evaluation of in planta RNAi

    PubMed Central

    Vieira, Paulo; Eves-van den Akker, Sebastian; Verma, Ruchi; Wantoch, Sarah; Eisenback, Jonathan D.; Kamo, Kathryn

    2015-01-01

    The root lesion nematode Pratylenchus penetrans is considered one of the most economically important species within the genus. Host range studies have shown that nearly 400 plant species can be parasitized by this species. To obtain insight into the transcriptome of this migratory plant-parasitic nematode, we used Illumina mRNA sequencing analysis of a mixed population, as well as nematode reads detected in infected soybean roots 3 and 7 days after nematode infection. Over 140 million paired end reads were obtained for this species, and de novo assembly resulted in a total of 23,715 transcripts. Homology searches showed significant hit matches to 58% of the total number of transcripts using different protein and EST databases. In general, the transcriptome of P. penetrans follows common features reported for other root lesion nematode species. We also explored the efficacy of RNAi, delivered from the host, as a strategy to control P. penetrans, by targeted knock-down of selected nematode genes. Different comparisons were performed to identify putative nematode genes with a role in parasitism, resulting in the identification of transcripts with similarities to other nematode parasitism genes. Focusing on the predicted nematode secreted proteins found in this transcriptome, we observed specific members to be up-regulated at the early time points of infection. In the present study, we observed an enrichment of predicted secreted proteins along the early time points of parasitism by this species, with a significant number being pioneer candidate genes. A representative set of genes examined using RT-PCR confirms their expression during the host infection. The expression patterns of the different candidate genes raise the possibility that they might be involved in critical steps of P. penetrans parasitism. This analysis sheds light on the transcriptional changes that accompany plant infection by P. penetrans, and will aid in identifying potential gene targets for selection and use to design effective control strategies against root lesion nematodes. PMID:26658731

  9. The influence of antibiotic production and pre-emptive colonization on the population dynamics of Pantoea agglomerans (Erwinia herbicola) Eh1087 and Erwinia amylovora in planta.

    PubMed

    Giddens, Stephen R; Houliston, Gary J; Mahanty, H Khris

    2003-10-01

    Stigma colonization by Erwinia amylovora is the crucial first step in the development of most fire blight infections in apple and pear trees. Suppression at this point of the disease process by antagonists of E. amylovora, such as Pantoea agglomerans (Erwinia herbicola) strain Eh1087, is a rational approach to control fire blight. We tested the hypothesis that the ability of E. amylovora to compete with Eh1087 for colonization of a stigma is reduced by the potential for Eh1087 to produce the phenazine antibiotic, d-alanylgriseoluteic acid (AGA). In competition experiments on the stigmas of apple flowers, E. amylovora was significantly less successful against Eh1087 (AGA+) than against EhDeltaAGA (AGA-). Further experiments to test the importance of pre-emptive colonization of the stigma by either the pathogen or the antagonist suggested that AGA production significantly enhanced the competitiveness of Eh1087 when it was applied at the same time or 24 h before the pathogen. We also found that pre-emptive stigma colonization by either the pathogen or the antagonist resulted in a population that was resilient to subsequent invasion by a second species suggesting that niche exclusion has a dominant influence on the dynamics of bacterial populations on stigmas. PMID:14510856

  10. In planta imaging of Δ9-tetrahydrocannabinolic acid in Cannabis sativa L. with hyperspectral coherent anti-Stokes Raman scattering microscopy

    NASA Astrophysics Data System (ADS)

    Garbacik, Erik T.; Korai, Roza P.; Frater, Eric H.; Korterik, Jeroen P.; Otto, Cees; Offerhaus, Herman L.

    2013-04-01

    Nature has developed many pathways to produce medicinal products of extraordinary potency and specificity with significantly higher efficiencies than current synthetic methods can achieve. Identification of these mechanisms and their precise locations within plants could substantially increase the yield of a number of natural pharmaceutics. We report label-free imaging of Δ9-tetrahydrocannabinolic acid (THCa) in Cannabis sativa L. using coherent anti-Stokes Raman scattering microscopy. In line with previous observations we find high concentrations of THCa in pistillate flowering bodies and relatively low amounts within flowering bracts. Surprisingly, we find differences in the local morphologies of the THCa-containing bodies: organelles within bracts are large, diffuse, and spheroidal, whereas in pistillate flowers they are generally compact, dense, and have heterogeneous structures. We have also identified two distinct vibrational signatures associated with THCa, both in pure crystalline form and within Cannabis plants; at present the exact natures of these spectra remain an open question.

  11. Seed development and maturation in early spring-flowering Galanthus nivalis and Narcissus pseudonarcissus continues post-shedding with little evidence of maturation in planta

    PubMed Central

    Newton, Rosemary J.; Hay, Fiona R.; Ellis, Richard H.

    2013-01-01

    Background and Aims Seeds of the moist temperate woodland species Galanthus nivalis and Narcissus pseudonarcissus, dispersed during spring or early summer, germinated poorly in laboratory tests. Seed development and maturation were studied to better understand the progression from developmental to germinable mode in order to improve seed collection and germination practices in these and similar species. Methods Phenology, seed mass, moisture content and ability to germinate and tolerate desiccation were monitored during seed development until shedding. Embryo elongation within seeds was investigated during seed development and under several temperature regimes after shedding. Key Results Seeds were shed at high moisture content (>59 %) with little evidence that dry mass accumulation or embryo elongation were complete. Ability to germinate developed prior to the ability of some seeds to tolerate enforced desiccation. Germination was sporadic and slow. Embryo elongation occurred post-shedding in moist environments, most rapidly at 20 °C in G. nivalis and 15 °C in N. pseudonarcissus. The greatest germination also occurred in these regimes, 78 and 48 %, respectively, after 700 d. Conclusions Seeds of G. nivalis and N. pseudonarcissus were comparatively immature at shedding and substantial embryo elongation occurred post-shedding. Seeds showed limited desiccation tolerance at dispersal. PMID:23478943

  12. Vascular Streak Dieback of cacao in Southeast Asia detection and Melanesia: in planta detection of the pathogen and a new taxonomy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular Streak Dieback (VSD) disease of cacao (Theobroma cacao) in Southeast Asia and Melanesia is caused by a basidiomycete (Ceratobasidiales) fungus described in a monotypic genus as Oncobasidium theobromae (syn. =Thanatephorus theobromae). The symptoms of the disease include green-spotted chloro...

  13. Proteins with High Turnover Rate in Barley Leaves Estimated by Proteome Analysis Combined with in Planta Isotope Labeling1[W][OPEN

    PubMed Central

    Nelson, Clark J.; Alexova, Ralitza; Jacoby, Richard P.; Millar, A. Harvey

    2014-01-01

    Protein turnover is a key component in cellular homeostasis; however, there is little quantitative information on degradation kinetics for individual plant proteins. We have used 15N labeling of barley (Hordeum vulgare) plants and gas chromatography-mass spectrometry analysis of free amino acids and liquid chromatography-mass spectrometry analysis of proteins to track the enrichment of 15N into the amino acid pools in barley leaves and then into tryptic peptides derived from newly synthesized proteins. Using information on the rate of growth of barley leaves combined with the rate of degradation of 14N-labeled proteins, we calculate the turnover rates of 508 different proteins in barley and show that they vary by more than 100-fold. There was approximately a 9-h lag from label application until 15N incorporation could be reliably quantified in extracted peptides. Using this information and assuming constant translation rates for proteins during the time course, we were able to quantify degradation rates for several proteins that exhibit half-lives on the order of hours. Our workflow, involving a stringent series of mass spectrometry filtering steps, demonstrates that 15N labeling can be used for large-scale liquid chromatography-mass spectrometry studies of protein turnover in plants. We identify a series of abundant proteins in photosynthesis, photorespiration, and specific subunits of chlorophyll biosynthesis that turn over significantly more rapidly than the average protein involved in these processes. We also highlight a series of proteins that turn over as rapidly as the well-known D1 subunit of photosystem II. While these proteins need further verification for rapid degradation in vivo, they cluster in chlorophyll and thiamine biosynthesis. PMID:25082890

  14. Regulon Studies and In Planta Role of the BraI/R Quorum-Sensing System in the Plant-Beneficial Burkholderia Cluster

    PubMed Central

    Coutinho, Bruna G.; Mitter, Birgit; Talbi, Chouhra; Sessitsch, Angela; Bedmar, Eulogio J.; Halliday, Nigel; James, Euan K.; Cámara, Miguel

    2013-01-01

    The genus Burkholderia is composed of functionally diverse species, and it can be divided into several clusters. One of these, designated the plant-beneficial-environmental (PBE) Burkholderia cluster, is formed by nonpathogenic species, which in most cases have been found to be associated with plants. It was previously established that members of the PBE group share an N-acyl-homoserine lactone (AHL) quorum-sensing (QS) system, designated BraI/R, that produces and responds to 3-oxo-C14-HSL (OC14-HSL). Moreover, some of them also possess a second AHL QS system, designated XenI2/R2, producing and responding to 3-hydroxy-C8-HSL (OHC8-HSL). In the present study, we performed liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis to determine which AHL molecules are produced by each QS system of this group of bacteria. The results showed that XenI2/R2 is mainly responsible for the production of OHC8-HSL and that the BraI/R system is involved in the production of several different AHLs. This analysis also revealed that Burkholderia phymatum STM815 produces greater amounts of AHLs than the other species tested. Further studies showed that the BraR protein of B. phymatum is more promiscuous than other BraR proteins, responding equally well to several different AHL molecules, even at low concentrations. Transcriptome studies with Burkholderia xenovorans LB400 and B. phymatum STM815 revealed that the BraI/R regulon is species specific, with exopolysaccharide production being the only common phenotype regulated by this system in the PBE cluster. In addition, BraI/R was shown not to be important for plant nodulation by B. phymatum strains or for endophytic colonization and growth promotion of maize by B. phytofirmans PsJN. PMID:23686262

  15. Taxonomic Treatment of Solanum Section Petota (Wild Potatoes) in Catálogo de Plantas Vasculares del Cono Sur (Argentina, Chile, Paraguay, Uruguay, y sur del Brasil)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solanum section Petota (Solanaceae), which includes the cultivated potato (Solanum tuberosum) and its wild relatives, contains over 150 wild species distributed from the southwestern U.S.A. (38°N) to central Argentina and adjacent Chile (41°S). This catalog includes all species from the Southern Con...

  16. Transient Co-Expression of Post-Transcriptional Gene Silencing Suppressors for Increased in Planta Expression of a Recombinant Anthrax Receptor Fusion Protein

    PubMed Central

    Arzola, Lucas; Chen, Junxing; Rattanaporn, Kittipong; Maclean, James M.; McDonald, Karen A.

    2011-01-01

    Potential epidemics of infectious diseases and the constant threat of bioterrorism demand rapid, scalable, and cost-efficient manufacturing of therapeutic proteins. Molecular farming of tobacco plants provides an alternative for the recombinant production of therapeutics. We have developed a transient production platform that uses Agrobacterium infiltration of Nicotiana benthamiana plants to express a novel anthrax receptor decoy protein (immunoadhesin), CMG2-Fc. This chimeric fusion protein, designed to protect against the deadly anthrax toxins, is composed of the von Willebrand factor A (VWA) domain of human capillary morphogenesis 2 (CMG2), an effective anthrax toxin receptor, and the Fc region of human immunoglobulin G (IgG). We evaluated, in N. benthamiana intact plants and detached leaves, the expression of CMG2-Fc under the control of the constitutive CaMV 35S promoter, and the co-expression of CMG2-Fc with nine different viral suppressors of post-transcriptional gene silencing (PTGS): p1, p10, p19, p21, p24, p25, p38, 2b, and HCPro. Overall, transient CMG2-Fc expression was higher on intact plants than detached leaves. Maximum expression was observed with p1 co-expression at 3.5 days post-infiltration (DPI), with a level of 0.56 g CMG2-Fc per kg of leaf fresh weight and 1.5% of the total soluble protein, a ten-fold increase in expression when compared to absence of suppression. Co-expression with the p25 PTGS suppressor also significantly increased the CMG2-Fc expression level after just 3.5 DPI. PMID:21954339

  17. Investigations of the in Planta Expression of Active Cellobiohydrolase I: Cooperative Research and Development Final Report, CRADA Number CRD-07-219

    SciTech Connect

    Himmel, M.

    2011-02-01

    It was the purpose of this project to determine if cellulases produced in transgenic plants could effectively be utilized in the production of ethanol and other feedstock chemicals from lignocellulosic substrates.

  18. In planta processing and glycosylation of a nematode CLE effector and its interaction with a CLV2-like receptor to promote parasitism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ESR (CLE)-like proteins have been identified in several cyst nematodes including the potato cyst nematode (PCN); however, th...

  19. Beetle and plant arrow poisons of the Ju|’hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae)

    PubMed Central

    Chaboo, Caroline S.; Biesele, Megan; Hitchcock, Robert K.; Weeks, Andrea

    2016-01-01

    Abstract The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San (“Bushmen”) arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called ‘click languages’ in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|’hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|’hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|’hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  20. Phylogenetic Analysis of Downy Mildew Pathogens of Opium Poppy and PCR-Based In Planta and Seed Detection of Peronospora arborescens.

    PubMed

    Landa, Blanca B; Montes-Borrego, Miguel; Muñoz-Ledesma, Francisco J; Jiménez-Díaz, Rafael M

    2007-11-01

    ABSTRACT Severe downy mildew diseases of opium poppy (Papaver somniferum) can be caused by Peronospora arborescens and P. cristata, but differentiating between the two pathogens is difficult because they share morphological features and a similar host range. In Spain, where severe epidemics of downy mildew of opium poppy have occurred recently, the pathogen was identified as P. arborescens on the basis of morphological traits. In this current study, sequence homology and phylogenetic analyses of the internal transcribed spacer regions (ITS) of the ribosomal DNA (rDNA) were carried out with DNA from P. arborescens and P. cristata from diverse geographic origins, which suggested that only P. arborescens occurs in cultivated Papaver somniferum in Spain. Moreover, analyses of the rDNA ITS region from 27 samples of downy-mildew-affected tissues from all opium-poppy-growing regions in Spain showed that genetic diversity exists within P. arborescens populations in Spain and that these are phylogenetically distinct from P. cristata. P. cristata instead shares a more recent, common ancestor with a range of Peronospora species that includes those found on host plants that are not members of the Papaveraceae. Species-specific primers and a PCR assay protocol were developed that differentiated P. arborescens and P. cristata and proved useful for the detection of P. arborescens in symptomatic and asymptomatic opium poppy plant parts. Use of these primers demonstrated that P. arborescens can be transmitted in seeds and that commercial seed stocks collected from crops with high incidence of the disease were frequently infected. Field experiments conducted in microplots free from P. arborescens using seed stocks harvested from infected capsules further demonstrated that transmission from seedborne P. arborescens to opium poppy plants can occur. Therefore, the specific-PCR detection protocol developed in this study can be of use for epidemiological studies and diagnosing the pathogen in commercial seed stocks; thus facilitating the sanitary control of the disease and avoidance of the pathogen distribution in seeds. PMID:18943506

  1. In planta biocatalysis screen of P450s identifies 8-methoxypsoralen as a substrate for the CYP82C subfamily, yielding original chemical structures.

    PubMed

    Kruse, Tanya; Ho, Kwongling; Yoo, Hye-Dong; Johnson, Thomas; Hippely, Matt; Park, Joon-Hyun; Flavell, Richard; Bobzin, Steve

    2008-02-01

    An in vivo plant screen that allows for the analysis of exogenously applied substrates against transgenic Arabidopsis lines overexpressing individual cytochrome P450s has been developed. By deploying this screen with a subset of 91 P450s, we have identified an original substrate for members of the CYP82C subfamily. The therapeutic compound 8-methoxypsoralen was hydroxylated by plants overexpressing CYP82C2 or CYP82C4, forming 5-hydroxy-8-methoxypsoralen. Additionally, plants further modified this product to create a glycosylated compound, likely the compound 5-O-beta-D-glucopyranosyl-8-methoxypsoralen. The discovery of adducts of therapeutic compounds demonstrates the potential of this biocatalysis screening approach to create compounds that may be of pharmacological value. Additionally, this platform provides a means to expand the general knowledge base of P450 enzyme/substrate combinations and may provide valuable tools for a vast array of biocatalytic and bioremediation processes. PMID:18291319

  2. Beetle and plant arrow poisons of the Ju|'hoan and Hai||om San peoples of Namibia (Insecta, Coleoptera, Chrysomelidae; Plantae, Anacardiaceae, Apocynaceae, Burseraceae).

    PubMed

    Chaboo, Caroline S; Biesele, Megan; Hitchcock, Robert K; Weeks, Andrea

    2016-01-01

    The use of archery to hunt appears relatively late in human history. It is poorly understood but the application of poisons to arrows to increase lethality must have occurred shortly after developing bow hunting methods; these early multi-stage transitions represent cognitive shifts in human evolution. This paper is a synthesis of widely-scattered literature in anthropology, entomology, and chemistry, dealing with San ("Bushmen") arrow poisons. The term San (or Khoisan) covers many indigenous groups using so-called 'click languages' in southern Africa. Beetles are used for arrow poison by at least eight San groups and one non-San group. Fieldwork and interviews with Ju|'hoan and Hai||om hunters in Namibia revealed major differences in the nature and preparation of arrow poisons, bow and arrow construction, and poison antidote. Ju|'hoan hunters use leaf-beetle larvae of Diamphidia Gerstaecker and Polyclada Chevrolat (Chrysomelidae: Galerucinae: Alticini) collected from soil around the host plants Commiphora africana (A. Rich.) Engl. and Commiphora angolensis Engl. (Burseracaeae). In the Nyae Nyae area of Namibia, Ju|'hoan hunters use larvae of Diamphidia nigroornata Ståhl. Larvae and adults live above-ground on the plants and eat leaves, but the San collect the underground cocoons to extract the mature larvae. Larval hemolymph is mixed with saliva and applied to arrows. Hai||om hunters boil the milky plant sap of Adenium bohemianum Schinz (Apocynaceae) to reduce it to a thick paste that is applied to their arrows. The socio-cultural, historical, and ecological contexts of the various San groups may determine differences in the sources and preparation of poisons, bow and arrow technology, hunting behaviors, poison potency, and perhaps antidotes. PMID:27006594

  3. SECONDARY METABOLITE PRODUCTION BY THE FUNGAL PATHOGEN EUTYPA LATA: ANALYSIS OF EXTRACTS FROM GRAPEVINE CULTURES AND DETECTION OF THOSE METABOLITES IN PLANTA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutypa dieback of grapevines is caused by the fungal pathogen Eutypa lata and reduces vineyard longevity worldwide. Early detection could reduce losses due to this disease, so our aim was to identify acetylenic phenol metabolites of E. lata that could prove suitable as chemical markers in an early d...

  4. In Planta Variation of Volatile Biosynthesis: An Alternative Biosynthetic Route to the Formation of the Pathogen-Induced Volatile Homoterpene DMNT via Triterpene Degradation in Arabidopsis Roots

    PubMed Central

    Sohrabi, Reza; Huh, Jung-Hyun; Badieyan, Somayesadat; Rakotondraibe, Liva Harinantenaina; Kliebenstein, Daniel J.; Sobrado, Pablo; Tholl, Dorothea

    2015-01-01

    Plant-derived volatile compounds such as terpenes exhibit substantial structural variation and serve multiple ecological functions. Despite their structural diversity, volatile terpenes are generally produced from a small number of core 5- to 20-carbon intermediates. Here, we present unexpected plasticity in volatile terpene biosynthesis by showing that irregular homo/norterpenes can arise from different biosynthetic routes in a tissue specific manner. While Arabidopsis thaliana and other angiosperms are known to produce the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) or its C16-analog (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene by the breakdown of sesquiterpene and diterpene tertiary alcohols in aboveground tissues, we demonstrate that Arabidopsis roots biosynthesize DMNT by the degradation of the C30 triterpene diol, arabidiol. The reaction is catalyzed by the Brassicaceae-specific cytochrome P450 monooxygenase CYP705A1 and is transiently induced in a jasmonate-dependent manner by infection with the root-rot pathogen Pythium irregulare. CYP705A1 clusters with the arabidiol synthase gene ABDS, and both genes are coexpressed constitutively in the root stele and meristematic tissue. We further provide in vitro and in vivo evidence for the role of the DMNT biosynthetic pathway in resistance against P. irregulare. Our results show biosynthetic plasticity in DMNT biosynthesis in land plants via the assembly of triterpene gene clusters and present biochemical and genetic evidence for volatile compound formation via triterpene degradation in plants. PMID:25724638

  5. "Entre Familia": Immigrant Parents' Strategies for Involvement in Children's Schooling

    ERIC Educational Resources Information Center

    Poza, Luis; Brooks, Maneka Deanna; Valdés, Guadalupe

    2014-01-01

    Teachers and administrators in schools with large, working-class Latino populations often complain of parents' indifference or lack of involvement in children's schooling because of their low visibility at school events and relatively little face-to-face communication with teachers and school administration. In a series of…

  6. Dominicanas entre La Gran Manzana y Quisqueya: Family, Schooling, and Language Learning in a Transnational Context

    ERIC Educational Resources Information Center

    Rodriguez, Tracy

    2009-01-01

    Drawing from a one-year qualitative research study, this article explores the transnational lives and experiences of three young women and their little sisters in New York with close ties to the Dominican Republic. Using ethnographic research methods--life history interviews, focus groups, participant observation, and document analysis, I examine…

  7. La formation a Bukavu au Zaire: une course entre l'education et la catastrophe

    NASA Astrophysics Data System (ADS)

    Balegamire, Bazilashe Juvénal

    1996-11-01

    A description of the socio-educational situation in Bukavu since the colonial era clearly shows why the population has sought means of overcoming the gradual abandonment by the Zairean State of its responsibilities, which has been aggravated by the large-scale influx into Kivu, in Eastern Zaire, of refugees from Rwanda and Burundi and of Zaireans who has been living in those countries for some years. These means are principally trade occupations, small-time selling, short-term vocational training and higher and university education at private institutions which are financed locally and/or by funds from the North. A new approach has been deveoped, that of training the trainers working for non-governmental development organisations. Trainers of trainers have been recruited locally among the many graduates of the Higher Institutes of Education and Rural Development, which have been affected by unemployment and the miserable salaries which the State offers to its employees. The trainers of trainers could be trained by the Higher Institute of Rural Development, making the largest possible use of local skills. However, such training should be one of a set of reforms of the Zairean education system. All of this only makes sense if Zaire and its neighbours urgently defuse present socio-political tensions so that all of our populations can peacefully and resolutely engage in the healthy transformation of our societies.

  8. Entre Dos Mundos/Between Two Worlds: Bicultural Development in Context

    ERIC Educational Resources Information Center

    Bacallao, Martica L.; Smokowski, Paul R.

    2009-01-01

    How do Mexican immigrant adolescents balance different, and often oppositional, cultural influences in the acculturation process? In this article, we explore how acculturating adolescents absorb cultural messages and go about creating their (multiple) identities. Guided by Alternation Theory, in-depth qualitative interviews were conducted with 12…

  9. Let's Talk About Water: Film Screenings as an Entrée to Water Science

    NASA Astrophysics Data System (ADS)

    Hooper, R. P.; Lilienfeld, L.; Arrigo, J.

    2011-12-01

    "Let's Talk about Water" is a film symposium designed to bring together experts and the public to talk about the complex water issues facing society. The format of the event is quite simple: a panel of experts and the audience view a water documentary (such as "FLOW", "Liquid Assets", or "Gasland") together and there is an extended moderated discussion period following the film between the panel and the audience. Properly handled, this simple format can be very effective. A film creates a context of subject and language for the discussion--it gets the audience and the panel on the same page. The moderators must actively manage the discussion, both challenging the panelists with follow up questions, asking questions to simplify the language the expert is using, and passing a question among panelists to bring out different points of view. The panelists are provided with the film in advance to view and, most importantly, meet the day before the event to discuss the film. This makes for a much more convivial discussion at the event. We have found that these discussions can easily be sustained for 90 to 120 minutes with active audience participation. This format has been applied at college campuses with a target audience of lower-level undergraduates. Student clubs are engaged to help with publicity before the event and to assist with registration and ushering during the event. Appropriate classes offer extra credit for student attendance to ensure a strong turnout. A Hollywood film ("Chinatown" in southern California, "A Civil Action" in Boston) is shown on campus during the week preceding the event to help advertise the event. The event itself is typically held on a Saturday with a morning screening of the film. The audience is provided with index cards and pencils to write down questions they have about the film. A lunch is provided during which the questions are organized and used to initiate different discussion themes. The discussion begins with points raised by the movie (are these issues real? Do they apply here? What are the scientific, engineering, and policy solutions to these problems?) and then segues into a discussion about career opportunities in the water sector. Our past events at UC Irvine and at UMass Boston have been successful in attracting large audiences and have been viewed positively by attendees.

  10. La Communicacion entre los Centros de Investigacion en Educacion (Communication among Educational Research Centers).

    ERIC Educational Resources Information Center

    Schiefelbein, Ernesto

    1972-01-01

    In Latin America there is a lack of communication concerning educational research. This lack has been underlined in many regional meetings, but no action has been taken. Possible steps that would lead to improvement include circulation of research summaries, both for completed and current works, efforts by research centers to organize meetings,…

  11. Actividades interrelacionadas entre el nino y la familia (Interrelated Activities between the Child and the Family).

    ERIC Educational Resources Information Center

    Veglio, Ana M.

    1993-01-01

    Offers a rationale for parent involvement in early childhood education. Describes the benefits of mother-child gymnastics in terms of the development of motor skills and positive attitudes toward school. Highlights particular exercises and games. (AC)

  12. Vinculación entre varios cúmulos estelares y estructuras del medio interestelar

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Baume, G. L.; Panei, J. A.; Suad, L. A.; Testori, J. C.; Borissova, J.; Kurtev, R.; Chené, A. N.; Ramirez Alegría, S.

    2015-08-01

    We study the embedded clusters DBS77, 78, 102, 160, and 161 located in the Galactic plane in the fourth quadrant of the Milky Way and the surrounding interstellar medium (ISM). We analyzed UBVIc photometry (SOAR) and infrared spectroscopy (NTT, ESO). We complemented these data with JHK (VVV2MASS), HI 21 cm bands (SGPS), 1.4 GHz (ATCA), and 4.85 GHz (PMN). We did multiband analysis and spectral classification of the brightest stars in each area. We also identified the ISM structures possibly related to the clusters. Finally, we obtained the main parameters of the studied clusters, the structures of the ISM and the link between them.

  13. New York: Les ecoles entre SURR et STAR (New York: Schools between SURR and STAR).

    ERIC Educational Resources Information Center

    Ueberschlag, Roger

    1994-01-01

    Three problems of New York City (New York) schools--overpopulation, low academic standards, violence--are examined, and an effort led by parent and teacher organizations to improve conditions is described. Threatened closings (schools under registration review, SURR) and a program of violence reduction (Straight Talk about Risks, STAR) are noted.…

  14. GPS, punto de contacto entre la Astronomía y otras disciplinas

    NASA Astrophysics Data System (ADS)

    Perdomo, R.

    En los primeros años de la pasada década, un grupo de Astrónomos de La Plata iniciaron trabajos de investigación en Geodesia Satelital. En esta presentación se propone repasar sus principales logros y situarlos en el contexto del desarrollo de la disciplina a nivel mundial. Por entonces las aplicaciones prácticas de la disciplina eran indirectas y solo evidentes para los especialistas. Los errores del Posicionamiento Satelital eran de varios metros y en posicionamiento relativo, del orden de medio metro. Estos resultados se lograban al cabo de varios días de medición continuada. En los años siguientes, el sistema GPS alcanzó su nivel operacional y produjo una revolución tanto en lo relacionado con los tiempos de medición como con las precisiones. El grupo de La Plata se desarrolló simultáneamente con GPS, lo que posibilitó su participación actual en diversos temas vigentes: aplicaciones de alta precisión para la materialización de sistemas terrestres de referencia, monitoreo de movimientos de la corteza, contribución con servicios internacionales para la determinación de movimientos tectónicos globales y regionales, monitoreo de la ionósfera a partir de la propagación de las señales, determinación de la ondulación del geoide a escala local, etc. También se generaron muchas aplicaciones prácticas algunas en tiempo real: navegación, apoyo a imágenes aéreas o satelitales, aplicaciones a la agricultura, catastro y ordenamiento territorial, apoyo a relevamientos geofísicos, etc.

  15. L'Harmonisation des langues maliennes: entre l'Integration nationale et régionale

    NASA Astrophysics Data System (ADS)

    Ouane, Adama

    1991-03-01

    The standardization of Malian languages, which began in the period after independence, has been an educational reform guided more by linguists than by any institutional framework laid down by the political authorities of the country. This situation has permitted the technical application of a scientific strategy, but it has not led to widespread and general acceptance of the formulas which have been worked out. The consequent opposition between technical and political considerations, which have admittedly not always been in conflict, has been complicated by a set of additional factors which have made it difficult to reconcile internal (national) harmonization, dictated by local tendencies and balances between languages, and the need to respect the (regional) ecolinguistics of the country, whose linguistic and sociocultural divisions frequently extend well into other countries of the sub-region. This conflict is illustrated by the example of Malian languages with a wide regional distribution — Bamanan (Bambara) and Fulfulde (Fulani) — and by that of languages with a narrower distribution such as Bomu and Syenara-Mamara. The standardization of orthography and the creation of terminology in the MAPE (Mandingo-Peul) Project are the manifestation of a general acceptance of regionalism, while the choice of central, standard languages has often been made without regard for regional factors.

  16. L' upwelling de la côte atlantique du Maroc entre 1994 et 1998

    NASA Astrophysics Data System (ADS)

    Makaoui, Ahmed; Orbi, Abdelattif; Hilmi, Karim; Zizah, Soukaina; Larissi, Jamila; Talbi, Mohammed

    2005-12-01

    The pelagic ecosystem of the Moroccan Atlantic coast is influenced by the spatiotemporal variability of upwelling. The changes in the physicochemical and biological parameters as well as their interrelationship and regrouping by the principal components analysis allowed us to subdivide the Atlantic coast in four active areas: two areas located at the north of Cape Juby (28°N), characterised by a summery activity and two areas located at the south, active permanently, with a variable intensity. To cite this article: A. Makaoui et al., C. R. Geoscience 337 (2005).

  17. Movimientos peculiares de galaxias en el Universo cercano

    NASA Astrophysics Data System (ADS)

    Alonso, M. V.

    Se presenta un resumen de los resultados más importantes obtenidos en los últimos años sobre movimientos peculiares en el Universo Cercano. En el escenario de inestabilidad gravitacional, el campo de velocidades peculiares es una herramienta muy útil para estimar las fluctuaciones en la distribución de masa que generan los movimientos observados. Esta aproximación puede, además, ser utilizada para poner restricciones al espectro de potencia de la masa, a la relación entre las distribuciones de galaxias y de materia y al valor del parámetro de densidad cosmológico, Ω, a grandes escalas. Son además presentados una reconstrucción preliminar de los campos de densidad de masa y velocidades peculiares en el universo cercano usando nuevas medidas de distancias obtenidas con la relación Dn - σ, para una muestra de galaxias elípticas y lenticulares. Dos subestructuras prominentes son encontradas en la región del Gran Atractor, que corresponden a los complejos de Centaurus y Pavo--Indus. Estos últimos, junto a los complejos de Perseus--Piscis y Cetus parecen ser importantes estructuras que determinan el flujo global. El patrón obtenido a través de una muestra de galaxias elípticas muestra variaciones con respecto al obtenido por galaxias espirales. Estos nuevos resultados muestran una coherencia menor en el flujo global, cuando son comparados con resultados obtenidos anteriormente.

  18. Medicinal ethnobotany in Huacareta (Chuquisaca, Bolivia)

    PubMed Central

    2012-01-01

    used as a base for subsequent work related to traditional medicine and its contribution to allopathic medicine in San Pablo de Huacareta. Resumen Introducción El objetivo del presente estudio fue documentar los tipos de enfermedades tratadas mediante el uso de plantas medicinales, sus aplicaciones principales y también tener un reporte de las enfermedades mayormente atendidas en el Hospital de San Pablo de Huacareta (Chuquisaca, Bolivia). Métodos Se realizaron encuestas semiestructuradas a 10 informantes locales anotando los usos atribuidos a sus plantas medicinales, se agruparon las plantas por categorías de enfermedades tratadas en la medicina tradicional. Se obtuvieron reportes de casos tratados en el Hospital de Huacareta para poder relacionar el tratamiento de enfermedades recurrentes en la zona entre la medicina tradicional y la medicina occidental. Resultados Se reportaron 91 especies nativas y exóticas, además de un espécimen indeterminado exótico que intervienen en un total de 258 aplicaciones medicinales, las cuales son empleadas en un total de 13 categorías de enfermedades. Los desórdenes gastrointestinales (55%) son mayormente tratados mediante plantas medicinales, seguidas de las afecciones al sistema esqueleto-muscular (25%) y enfermedades dermatológicas (24%). La información del Hospital indica que las enfermedades más frecuentes son Infecciones Respiratorias Agudas (47%) y Enfermedades Diarreicas Agudas (37%). Los remedios vegetales se emplean en forma de infusiones y cocciones principalmente. Se emplean mayormente plantas nativas, también se introdujo en la farmacopea médica el uso de plantas exóticas al lugar. Conclusiones El tratamiento de trastornos gastrointestinales constituye el objetivo primordial de la etnobotánica médica de los habitantes de Huacareta, las enfermedades del sistema respiratorio, son mayormente tratadas en el Hospital. Observando los datos del libro de consultas del Hospital, se puede inferir que los des

  19. Transition quantique entre états électroniques de systèmes bi-couche

    NASA Astrophysics Data System (ADS)

    Pasquier, Vincent

    The possible phase transitions when two layers at filling factor νt=1 are gradually separated are studied in this article. In the bosonic case the system should undergo a pairing transition from a Fermi liquid to an incompressible state. In the Fermionic case, the state evolves from an incompressible (1,1,1) state to a Fermi liquid. It is speculated that there is an intermediate phase involving charge two quasiparticles. To cite this article: V. Pasquier, C. R. Physique 3 (2002) 709-715.

  20. Henri Chretien, un savant entre science et technique: reflections a propos de l'invention de l'hypergonar

    NASA Astrophysics Data System (ADS)

    Le Guet Tully, Francoise

    At the beggining of the 20-th century, French engineers and scientists were not well acquainted with some of the importnat principles of applied optics developed elsewhere, especially in Germany, over the preceding fifty years. In preparation for a career as a designer of astronomical instruments, Henri Chretien visited observatories in several countries and read widely. His research in optics produced many tangible advances. The Richy-Chretien telescope, which gained popularity in the 1960s and still in use today, was designed in 1910, based on an application of the principles developed by Abbe in Germany first to make color movies and then, though another application of the same principle, to project motion pictures onto a wide screen (The "Hypergonar" objective).

  1. Entre el Renacimiento y el Nuevo Mundo: Vida y obras de Hernan Perez de Oliva (1494?-1531)

    ERIC Educational Resources Information Center

    Pellus Perez, Elena

    2012-01-01

    Hernan Perez de Oliva (1494?-1531) was a learned Spanish humanist who wrote his major works in the decades following the discovery of America. By articulating events of his career and literary life, my goal is to comprehend his contributions to the early literary production regarding the newly-found Americas. The thesis consists of three parts.…

  2. Detection of PhIP in grilled chicken entrées at popular chain restaurants throughout California.

    PubMed

    Sullivan, Kristie M; Erickson, Michael A; Sandusky, Chad B; Barnard, Neal D

    2008-01-01

    Heterocyclic amines (HCAs), compounds formed when meat is cooked at high temperatures particularly through pan frying, grilling, or barbequing, pose a potential carcinogenic risk to the public. It is unclear whether there is any level at which consumption of HCAs can be considered safe. Efforts to measure these compounds mainly include cooking studies under laboratory conditions and some measurement of home-cooked foods, but analysis of commercially cooked foods has been minimal. Attempts to estimate exposure of the public to these compounds must take into consideration dining outside the home, which could result in significant exposure for some individuals. We surveyed at least 9 locations each of 7 popular chain restaurants (McDonald's, Burger King, Chick-fil-A, Chili's, TGI Friday's, Outback Steakhouse, and Applebee's) in California, collecting one or two entrees from each location. Entrees were analyzed for 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) using high-performance liquid chromatography tandem mass spectrometry. All 100 samples contained PhIP. Concentrations were variable within and between entrees and ranged from 0.08 to 43.2 ng/g. When factoring in the weight of the entrees, absolute levels of PhIP reached over 1,000 ng for some entrees. Potential strategies for reducing exposure include the avoidance of meats cooked using methods that are known to form PhIP. PMID:18791922

  3. Neuropatía persistente aumenta el riesgo de caídas entre supervivientes de cáncer

    Cancer.gov

    Muchas mujeres supervivientes de cáncer tienen problemas de movilidad y de otras funciones físicas como resultado de la neuropatía periférica persistente causada por el tratamiento de quimioterapia, según un estudio nuevo.

  4. Interactivite, relations entre interlocuteurs et constitution d'unites conversationnelles (Interaction Processes, Participants' Relationships and Definition of Conversation Units).

    ERIC Educational Resources Information Center

    Zenone, Anna

    1981-01-01

    Analyzes a type of conversational exchange where the participants focus on a given subject or theme contributing personal views to the discussion. Characterizes the relationship among the participants as a "cooperative conflict," examining the internal structure of speech acts and their illocutory functions, particularly the initiatory and…

  5. Alternancia entre el estado de emisión de Rayos-X y Pulsar en Sistemas Binarios Interactuantes

    NASA Astrophysics Data System (ADS)

    De Vito, M. A.; Benvenuto, O. G.; Horvath, J. E.

    2015-08-01

    Redbacks belong to the family of binary systems in which one of the components is a pulsar. Recent observations show redbacks that have switched their state from pulsar - low mass companion (where the accretion of material over the pulsar has ceased) to low mass X-ray binary system (where emission is produced by the mass accretion on the pulsar), or inversely. The irradiation effect included in our models leads to cyclic mass transfer episodes, which allow close binary systems to switch between one state to other. We apply our results to the case of PSR J1723-2837, and discuss the need to include new ingredients in our code of binary evolution to describe the observed state transitions.

  6. Estimation du risque collisionnel entre une sonde spatiale cométaire et un fragment du noyau

    NASA Astrophysics Data System (ADS)

    Desvoivres, Emmanuel; Klinger, Jürgen; Levasseur-Regourd, Anny-Chantal

    2000-03-01

    Several comets will be approached by space probes during the two next decades. The presence of a fragment of the nucleus in the coma is a real danger. We have estimated the probability of presence of a boulder in the inner coma, using a model for the dynamics of fragments. Specific recommandations are deduced in order to reduce the risk of a collision.

  7. Metonymie dans la presse ecrite: entre discours et langue (Metonymies in the Press: Between Discourse and Language).

    ERIC Educational Resources Information Center

    Lecolle, Michelle

    2001-01-01

    This paper describes certain metonymies that are often employed in the daily French press. In such metonymies, a human being or a set of individuals are referred to by means of the name of an institutional location (i.e., a capital city, a ministry in a western country, the name of a country). These metonymic patterns do not seem to be used by…

  8. Diriger un Memoire Professionnel--Entre Dispositif Institutionnel et Problematique Relationnelle: Le Cas de la Formation des Enseignants en France.

    ERIC Educational Resources Information Center

    Bailleul, Marc; Bodergat, Jean-Yves

    2001-01-01

    Describes research conducted in a French teacher training college about the supervision of preservice teachers writing professional dissertations (which became compulsory in 1991). After describing elementary and secondary level preservice teachers' perspectives, researchers examined the perspectives of their supervisors to show discrepancies.…

  9. Modelisation de l'interaction entre une impulsion laser ultrabreve et une nanostructure plasmonique en milieu aqueux

    NASA Astrophysics Data System (ADS)

    Boulais, Etienne

    There is still a limited understanding of the basic mechanisms and processes triggered by laser irradiation that lead to the damaging of the surrounding structures. In particular, there exists for the moment no complete modelling of the process that includes all potential sources of cellular damage, including temperature rise, plasma generation, pressure wave emission and vapor bubble formation. This thesis presents such a modelling, with the cell environment emulated by a much simpler aqueous medium. Water is used as its optical, mechanical and thermal characteristic are similar enough to the cell environment to enable the transposition of the results and tendencies observed in water to this medium. Modelling consists in a continuous medium based approach that uses coupled partial differential equations to simulate the nanostructure-water system's response to an ultrafast laser pulse. The time-dependant field distribution in the system is simulated using classical electromagnetic theory, while the temperature in the nanostructure is calculated using a two-temperature model. Generation and heating of a plasma in the nanostructure's vicinity from photoionization and impact ionization in the near-field, as well as from photothermal emission from the nanostructure at the metal interface are also included. This plasma locally modifies the refractive index, which alters the simulated optical response of the system. Energy relaxation from this plasma as well as heat conduction from the nanostructure's lattice transfer energy to the water, which dynamics and thermodynamics evolutions are simulated from hydrodynamic and energy conservation equations. Modelling is used for analyzing the interaction of a near-infrared ultrafast laser pulse (45 fs, 800 nm, 200 mJ/cm2) with two distinct systems : a 100nm gold nanoparticle and a 10x41 nm2 gold nanorod. The gold nanoparticle shows a plasmon resonance at a ˜550 nm wavelength, and is thus slightly off-resonance at the 800 nm irradiation wavelength. In opposition, the gold nanorod shows a plasmon resonance directly at 800 nm and is thus in-resonance at the irradiation wavelength. The system of tightly coupled time-dependant non-linear partial differential equations is solved in 3D using a finite-element method. The modelling shows the generation of vapor bubble around both systems, which maximal diameter and growth time are validated from spectroscopic measurements. Results show an important production of plasma in the nanostructure's near field, which fast relaxation heats rapidly the surrounding water, leading to the emission of strong pressure wave and to the formation of a vapor bubble. Simulations further demonstrate the crucial importance of the plasma in the cavitation mechanism. For both the nanoparticle and the nanorod, results show that most of the laser energy is indeed absorbed in the plasma surrounding the nanostructure rather than in the nanostructure itself. In particular, the energy absorbed in the nanoparticle is shown to be insufficient to induce the formation of a vapor bubble at 200 mJ/cm2, whereas such a bubble is experimentally observed. This is a major result of the thesis, as such a plasma-mediated plasmonic enhanced cavitation mechanism has never been reported in the literature. The existence of this plasma-mediated mechanism that does not rely on the particle extreme heating to initiate cavitation has important consequences on cell nanosurgery applications. Finally, based on the same modelling, we develop a simple and efficient method to evaluate the potential of specific nanostructures and irradiation parameters for cell nanosurgery. We introduce a performance factor based on minimizing the energy density deposited in the nanostructure to avoid fragmentation, while maximizing the overall energy deposited in the system, to enhance the production of vapor bubbles. Results predict off-resonance 175 nm gold nanoparticles to be best suited for near-infrared ultrafast laser cell nanosurgery using 45 fs pulses at a wavelength of 800 nm. They also confirm the low inte

  10. Analysis of Two in Planta Expressed LysM Effector Homologs from the Fungus Mycosphaerella graminicola Reveals Novel Functional Properties and Varying Contributions to Virulence on Wheat1[W][OA

    PubMed Central

    Marshall, Rosalind; Kombrink, Anja; Motteram, Juliet; Loza-Reyes, Elisa; Lucas, John; Hammond-Kosack, Kim E.; Thomma, Bart P.H.J.; Rudd, Jason J.

    2011-01-01

    Secreted effector proteins enable plant pathogenic fungi to manipulate host defenses for successful infection. Mycosphaerella graminicola causes Septoria tritici blotch disease of wheat (Triticum aestivum) leaves. Leaf infection involves a long (approximately 7 d) period of symptomless intercellular colonization prior to the appearance of necrotic disease lesions. Therefore, M. graminicola is considered as a hemibiotrophic (or necrotrophic) pathogen. Here, we describe the molecular and functional characterization of M. graminicola homologs of Ecp6 (for extracellular protein 6), the Lysin (LysM) domain-containing effector from the biotrophic tomato (Solanum lycopersicum) leaf mold fungus Cladosporium fulvum, which interferes with chitin-triggered immunity in plants. Three LysM effector homologs are present in the M. graminicola genome, referred to as Mg3LysM, Mg1LysM, and MgxLysM. Mg3LysM and Mg1LysM genes were strongly transcriptionally up-regulated specifically during symptomless leaf infection. Both proteins bind chitin; however, only Mg3LysM blocked the elicitation of chitin-induced plant defenses. In contrast to C. fulvum Ecp6, both Mg1LysM and Mg3LysM also protected fungal hyphae against plant-derived hydrolytic enzymes, and both genes show significantly more nucleotide polymorphism giving rise to nonsynonymous amino acid changes. While Mg1LysM deletion mutant strains of M. graminicola were fully pathogenic toward wheat leaves, Mg3LysM mutant strains were severely impaired in leaf colonization, did not trigger lesion formation, and were unable to undergo asexual sporulation. This virulence defect correlated with more rapid and pronounced expression of wheat defense genes during the symptomless phase of leaf colonization. These data highlight different functions for MgLysM effector homologs during plant infection, including novel activities that distinguish these proteins from C. fulvum Ecp6. PMID:21467214

  11. Methodology for producing 100 tons of fuel peat for a cement plant test burn. Metodologia para producir 100 toneladas de turba combustible para una prueba de quema en uns planta de cemento

    SciTech Connect

    Allen, A.B.; Malavassi, L.; Ramirez, O.; Thayer, G. , Plymouth, NC; RECOPE, San Jose; Los Alamos National Lab., NM )

    1989-05-01

    As a part of the Agency for International Development-funded cooperative project between Los Alamos and Costa Rica, the burning characteristics of Costa Rican peat were to be tested in an application. The cement plant owned by Industria National de Cemento in Cartago has a capability to handle solid fuel and was chosen for the burn demonstration. The Jungle No. 1 Peat Deposit near El Cairo was chosen as the site of the peat excavation. This peat production methodology study covers project site selection, installation of an access road and clearing of the jungle vegetation, removal of an upper layer of organic peat, excavation of fuel-grade peat, transport of the peat to the drying site, and drying and stockpiling of the finished product. As of this date the peat removal for the demonstration project has been started, and a description of the operation is included as an appendix to this paper. 10 figs.

  12. Combination of Novel Green Fluorescent Protein Mutant TSapphire and DsRed Variant mOrange to Set Up a Versatile in Planta FRET-FLIM Assay1[W

    PubMed Central

    Bayle, Vincent; Nussaume, Laurent; Bhat, Riyaz A.

    2008-01-01

    Förster resonance energy transfer (FRET) measurements based on fluorescence lifetime imaging microscopy (FLIM) are increasingly being used to assess molecular conformations and associations in living systems. Reduction in the excited-state lifetime of the donor fluorophore in the presence of an appropriately positioned acceptor is taken as strong evidence of FRET. Traditionally, cyan fluorescent protein has been widely used as a donor fluorophore in FRET experiments. However, given its photolabile nature, low quantum yield, and multiexponential lifetime, cyan fluorescent protein is far from an ideal donor in FRET imaging. Here, we report the application and use of the TSapphire mutant of green fluorescent protein as an efficient donor to mOrange in FLIM-based FRET imaging in intact plant cells. Using time-correlated single photon counting-FLIM, we show that TSapphire expressed in living plant cells decays with lifetime of 2.93 ± 0.09 ns. Chimerically linked TSapphire and mOrange (with 16-amino acid linker in between) exhibit substantial energy transfer based on the reduction in the lifetime of TSapphire in the presence of the acceptor mOrange. Experiments performed with various genetically and/or biochemically known interacting plant proteins demonstrate the versatility of the FRET-FLIM system presented here in different subcellular compartments tested (cytosol, nucleus, and at plasma membrane). The better spectral overlap with red monomers, higher photostability, and monoexponential lifetime of TSapphire makes it an ideal FRET-FLIM donor to study protein-protein interactions in diverse eukaryotic systems overcoming, in particular, many technical challenges encountered (like autofluorescence of cell walls and fluorescence of pigments associated with photosynthetic apparatus) while studying plant protein dynamics and interactions. PMID:18621983

  13. Arabidopsis SHR and SCR transcription factors and AUX1 auxin influx carrier control the switch between adventitious rooting and xylogenesis in planta and in in vitro cultured thin cell layers

    PubMed Central

    Della Rovere, F.; Fattorini, L.; D’Angeli, S.; Veloccia, A.; Del Duca, S.; Cai, G.; Falasca, G.; Altamura, M. M.

    2015-01-01

    Background and Aims Adventitious roots (ARs) are essential for vegetative propagation. The Arabidopsis thaliana transcription factors SHORT ROOT (SHR) and SCARECROW (SCR) affect primary/lateral root development, but their involvement in AR formation is uncertain. LAX3 and AUX1 auxin influx carriers contribute to primary/lateral root development. LAX3 expression is regulated by SHR, and LAX3 contributes to AR tip auxin maximum. In contrast, AUX1 involvement in AR development is unknown. Xylogenesis is induced by auxin plus cytokinin as is AR formation, but the genes involved are largely unknown. Stem thin cell layers (TCLs) form ARs and undergo xylogenesis under the same auxin plus cytokinin input. The aim of this research was to investigate SHR, SCR, AUX1 and LAX3 involvement in AR formation and xylogenesis in intact hypocotyls and stem TCLs in arabidopsis. Methods Hypocotyls of scr-1, shr-1, lax3, aux1-21 and lax3/aux1-21 Arabidopsis thaliana null mutant seedlings grown with or without auxin plus cytokinin were examined histologically, as were stem TCLs cultured with auxin plus cytokinin. SCR and AUX1 expression was monitored using pSCR::GFP and AUX1::GUS lines, and LAX3 expression and auxin localization during xylogenesis were monitored by using LAX3::GUS and DR5::GUS lines. Key Results AR formation was inhibited in all mutants, except lax3. SCR was expressed in pericycle anticlinally derived AR-forming cells of intact hypocotyls, and in cell clumps forming AR meristemoids of TCLs. The apex was anomalous in shr and scr ARs. In all mutant hypocotyls, the pericycle divided periclinally to produce xylogenesis. Xylary element maturation was favoured by auxin plus cytokinin in shr and aux1-21. Xylogenesis was enhanced in TCLs, and in aux1-21 and shr in particular. AUX1 was expressed before LAX3, i.e. in the early derivatives leading to either ARs or xylogenesis. Conclusions AR formation and xylogenesis are developmental programmes that are inversely related, but they involve fine-tuning by the same proteins, namely SHR, SCR and AUX1. Pericycle activity is central for the equilibrium between xylary development and AR formation in the hypocotyl, with a role for AUX1 in switching between, and balancing of, the two developmental programmes. PMID:25617411

  14. In planta Identification of Putative Pathogenicity Factors from the Chickpea Pathogen Ascochyta rabiei by De novo Transcriptome Sequencing Using RNA-Seq and Massive Analysis of cDNA Ends

    PubMed Central

    Fondevilla, Sara; Krezdorn, Nicolas; Rotter, Björn; Kahl, Guenter; Winter, Peter

    2015-01-01

    The most important foliar diseases in legumes worldwide are ascochyta blights. Up to now, in the Ascochyta-legume pathosystem most studies focused on the identification of resistance genes in the host, while very little is known about the pathogenicity factors of the fungal pathogen. Moreover, available data were often obtained from fungi growing under artificial conditions. Therefore, in this study we aimed at the identification of the pathogenicity factors of Ascochyta rabiei, causing ascochyta blight in chickpea. To identify potential fungal pathogenicity factors, we employed RNA-seq and Massive Analysis of cDNA Ends (MACE) to produce comprehensive expression profiles of A. rabiei genes isolated either from the fungus growing in absence of its host or from fungi infecting chickpea leaves. We further provide a comprehensive de novo assembly of the A. rabiei transcriptome comprising 22,725 contigs with an average length of 1178 bp. Since pathogenicity factors are usually secreted, we predicted the A. rabiei secretome, yielding 550 putatively secreted proteins. MACE identified 596 transcripts that were up-regulated during infection. An analysis of these genes identified a collection of candidate pathogenicity factors and unraveled the pathogen's strategy for infecting its host. PMID:26648917

  15. Prediction uncertainty of plume characteristics derived from a small number of measuring points

    NASA Astrophysics Data System (ADS)

    French, H. K.; van der Zee, S. E. A. T. M.; Leijnse, A.

    sensibles à la dimension du panache en fonction de la distance entre les différents points de mesure. Afin de réduire les erreurs de prédiction de la variance, la distance entre les points de mesure doit être inférieure au double de l'écart-type du panache examiné. La dimension totale de l'ensemble doit couvrir une étendue de plusieurs écarts-types du panache pour éviter qu'une partie de la matière échappe à la zone surveillée. Des simulations numériques du panache en dispersion (les calculs de comparaison sont basés sur 9000 nœuds avec 30 points de mesure) montrent que le centre vertical et le centre horizontal de la matière dispersée ont été bien prédits à tous les degrés d'hétérogénéité, de même que pour les variances horizontales. Les variances verticales ont été plus sensibles aux erreurs de prédiction, mais les estimations étaient du même ordre de grandeur que les valeurs réelles. Resumen Un número pequeño de puntos de medida puede producir un sesgo en la caracterización en campo del flujo y transporte de solutos en la zona no saturada. La simulación de transporte advectivo (no difusivo) de un penacho Gaussiano a travs de un conjunto de 30 puntos de medida regularmente distribuidos revelan fluctuaciones temporales regulares de los momentos espaciales del penacho. Una distribución irregular de puntos de medida predijo a su vez fluctuaciones irregulares, más alejadas de la realidad, por lo que se recomienda el uso de esquemas de muestreo regulares. Los momentos espaciales fueron sensibles a la relación entre tamaño del penacho y distancia entre puntos de medida. Para reducir los errores en la predicción de la varianza, la distancia entre puntos de observación debe ser menor que dos veces la desviación estándar del penacho. El tamaño del área muestreada debe cubrir varias desviaciones estándar del penacho para evitar perder parte de la masa. Las simulaciones numricas en un penacho dispersivo, comparando los c

  16. 77 FR 14594 - Additions to the Identifying Information for an Individual Previously Designated Pursuant to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ..., Planta Baja, Colonia Lomas Country Club, Huixquilucan, Estado de Mexico C.P. 52779, Mexico; Camino del..., No. 80 A, Planta Baja, Colonia Lomas Country Club, Huixquilucan, Estado de Mexico C.P. 52779,...

  17. 76 FR 59483 - Additional Designations, Foreign Narcotics Kingpin Designation Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ...; Camino del Remanso, No. 80 A, Planta Baja, Colonia Lomas Country Club, Huixquilucan, Estado de Mexico C.P..., Estado de Mexico C.P. 52779, Mexico; Camino del Remanso, No. 80 A, Planta Baja, Colonia Lomas...

  18. Diet of a sigmodontine rodent assemblage in a Peruvian montane forest

    PubMed Central

    Sahley, Catherine Teresa; Cervantes, Klauss; Pacheco, Victor; Salas, Edith; Paredes, Diego; Alonso, Alfonso

    2015-01-01

    comportamiento de forrajeo en roedores, aún existen grandes vacíos en nuestra comprensión de sus gremios tróficos. Nuestro objetivo fue investigar las dietas de siete especies de pequeños (< 100 g) roedores sigmodontinos simpátricos en un bosque montano andino a 3.500] m en Perú. Cualitativamente y cuantitativamente evaluamos la dieta en muestras fecales de roedores capturados entre el 2009 y el 2012. Datos de frecuencia para cuatro categorías de dieta indicaron que las siete especies de roedores consumieron cuatro categorías de dieta: artrópodos (88%), pedazos de hojas y fibras de plantas (61%), semillas intactas (con o sin pulpa de frutos; 50%), y esporas de micorrizas (45%). Omnivoría fue la estrategia utilizada por todas las especies, aunque el análisis con tablas de contingencia reveló diferencias significativas entre y dentro de especies en categorías de dieta. El análisis de agrupación presentó 2 grupos principales: el grupo Thomasomys spp. y Calomys sorellus, que incluye una gran proporción de semillas intactas, y partes de plantas en las muestras fecales y el grupo que incluye los géneros Akodon, Microryzomys y Oligoryzomys, el cual incluyó una proporción mayor de artrópodos en sus muestras fecales, pero con niveles altos de semillas intactas. Semillas intactas de al menos 17 especies de plantas (9 familias) fueron encontradas en las muestras fecales. Concluimos que este ensamble de roedores sigmodontinos es omnívoro y que probablemente las especies juegan un rol importante como frugívoros y en la dispersión de semillas en los bosques montanos tropicales en el Perú. PMID:26937050

  19. Planificación Neuroquirúrgica con Software Osirix

    PubMed Central

    Jaimovich, Sebastián Gastón; Guevara, Martin; Pampin, Sergio; Jaimovich, Roberto; Gardella, Javier Luis

    2014-01-01

    Introducción: La individualidad anatómica es clave para reducir el trauma quirúrgico y obtener un mejor resultado. Actualmente, el avance en las neuroimágenes ha permitido objetivar esa individualidad anatómica, permitiendo planificar la intervención quirúrgica. Con este objetivo, presentamos nuestra experiencia con el software Osirix. Descripción de la técnica: Se presentan 3 casos ejemplificadores de 40 realizados. Caso 1: Paciente con meningioma de la convexidad parasagital izquierda en área premotora; Caso 2: Paciente con macroadenoma hipofisario, operada previamente por vía transeptoesfenoidal en otra institución con una resección parcial; Caso 3: Paciente con lesiones en pedúnculo cerebeloso medio bilateral. Se realizó la planificación prequirúrgica con el software OsiriX, fusionando y reconstruyendo en 3D las imágenes de TC e IRM, para analizar relaciones anatómicas, medir distancias, coordenadas y trayectorias, entre otras funciones. Discusión: El software OsiriX de acceso libre y gratuito permite al cirujano, mediante la fusión y reconstrucción en 3D de imágenes, analizar la anatomía individual del paciente y planificar de forma rápida, simple, segura y económica cirugías de alta complejidad. En el Caso 1 se pudo analizar las relaciones del tumor con las estructuras adyacentes para minimizar el abordaje. En el Caso 2 permitió comprender la anatomía post-operatoria previa del paciente, para determinar la trayectoria del abordaje transnasal endoscópico y la necesidad de ampliar su exposición, logrando la resección tumoral completa. En el Caso 3 permitió obtener las coordenadas estereotáxicas y trayectoria de una lesión sin representación tomográfica. Conclusión: En casos de no contar con costosos sistemas de neuronavegación o estereotáxia el software OsiriX es una alternativa a la hora de planificar la cirugía, con el objetivo de disminuir el trauma y la morbilidad operatoria. PMID:25165617

  20. Internet, Multimedia and Virtual Laboratories in a 'Third World' Environment.

    ERIC Educational Resources Information Center

    Monge-Najera, Julian Antonio; Rivas Rossi, Marta; Mendez-Estrada, Victor Hugo

    2001-01-01

    Describes the development of low-cost multimedia courses and materials for use on the Internet, as well as virtual laboratories, at the Universidad Estatal a Distancia (Costa Rica). Explains how simultaneous production of traditional printed materials and online courses, outsourcing, and the use of HTML and Java can reduce costs for developing…

  1. Analysis of the Use of Twitter as a Learning Strategy in Master's Studies

    ERIC Educational Resources Information Center

    Feliz, Tiberio; Ricoy, Carmen; Feliz, Sálvora

    2013-01-01

    The present study analyses the use of Twitter in the course Social Media and Digital Learning, taught as part of a master's programme at Universidad Nacional de Educacion a Distancia (Spain). The main purpose of the use of this resource was to develop a learning community. This was implemented through the micro design of activities. A mixed…

  2. Revista Interamericana de Educacion de Adultos, 2003 (Interamerican Review of Adult Education, 2003).

    ERIC Educational Resources Information Center

    Guerra, Alfonso Rangel, Ed.

    2003-01-01

    This journal offers a collection of Spanish-language articles, including: "Educacion a Distancia y Uso de las Tecnologias: Experiencias Desafios y Oportunidades Educativas para Jovenes y Adultos" (Ma. Mercedes Ruiz); "Volver a a Educacion Fundamental? Notas para una Arquelogia de los Mandatos Fundacionales del CREFAL" (Jorge Rivas Diaz); "Una…

  3. Tools for evaluating Lipolexis oregmae (Hymenoptera: Aphidiidae) in the field: Effects of host aphid and host plant on mummy location and color plus improved methods for obtaining adults

    SciTech Connect

    Singh, R.; Hoy, M.A.

    2007-03-15

    , nosotros evaluamos el papel de otras especies de afidos y plantas hospederas potenciales sobre la produccion y ubicacion de las momias. Bajo condiciones de laboratorio, este parasitoide produjo el mayor numero de progenies sobre la especie de plaga enfocada, el afido pardo de los citricos sobre Citrus . Este parasitoide, no como la mayoria de los afidiidos (Hymenoptera), no produjo momias sobre cualquiera de las plantas hospederas probadas cuando fue criado sobre el afido negro de los citricos, ( T. aurantii (Boyer de Fonscolombe)) en toronja, el afido spirea (Aphis spiraecola Patch) en toronja y pittosporum, el afido del caupi (A. craccivora Koch) en toronja y caupi o el afido del melon (A. gossypii Glover) en toronja y pepino. Asi, el muestreo para momias de L. oregmae de estas especies de afidos hospederos y plantas hospederas tiene que incluir el mantenimiento de follaje en el laboratorio hasta que se produzcan las momias. Este parasitoide requiere una alta humedad relativa para producir los adultos por que ningun adulto emergio cuando las momias fueron mantenidas en capsulas de gelatina, pero una tasa alta de emergencia de adultos fue observada cuando se mantuvo las momias en platos con agar al 1.5%. Ademas de esto, nosotros comparamos el color de 6 especies de afidos hospederos, asi como el color de las momias producidos por L. oregmae cuando fue criado sobre ellos para determinar si se puede usar el color de las momias para la identificacion de L. oregmae . El color de las momias varia entre las especies de afidos hospederos y las plantas hospederas probadas, por lo que no es una herramienta util para la identificacion de L. oregmae o para la evaluacion de su efecto sobre los organismos que no son el enfoque del control. (author)

  4. Entre dois mundos: vida quotidiana de criancas portuguesas na america [Between Two Worlds: The Daily Life of Portuguese Children in America].

    ERIC Educational Resources Information Center

    de Meneses, Fernando

    This Portuguese reader with accompanying teacher's guide describes the culture shock that Portuguese children and their families face when they immigrate to North America. The reader is divided into 75 short stories about the families that come from the rural areas of Portugal where there has been little industrialization. The purpose of the…

  5. Modelo Crosscultural de Pasantias para Lideres de la Educacion: Cooperacion entre Estados Unidos y Venezuela (Designing an Effective School Administrator Internship Program: United States and Venezuela Cooperation).

    ERIC Educational Resources Information Center

    Serafin, Ana Gil; Thompson, Eugene W.

    A model was developed of an internship program designed to give valuable cross-cultural experience to school administrators in training at universities in the United States and Venezuela. A naturalistic approach was used to develop the model. Leading school administrators and educational leadership theorists in both countries were interviewed by…

  6. Etude, par principes premiers, des effets de la correlation entre electrons sur les proprietes electroniques et magnetiques de polymeres pontes et de supraconducteurs a haute temperature critique

    NASA Astrophysics Data System (ADS)

    Pesant, Simon

    Description of complex systems by Density functional theory is treated in this thesis. First, the Density functional theory and a few functionals used to simulate cristals are presented. Specifically, the LDA and GGA functionnals are described and their limits are exposed. Furthermore, the Hubbard model as well as the LDA+U functionnal are addressed in this chapter. These methods enable the study of highly correlated materials. Then, results obtained on polymers are summarized in two articles. The first one treats the band gap variation of ladder-type polymers compared to non ladder type ones. The second article considers small band gap polymers. In this case, it will be shown that an hybrid functional, which contains exact exchange, is required to describe the electronic properties of the polymers under study. Finally, the last chapter address the study of cuprates superconductors. The LDA+U can account for the localization of electrons in copper orbitals. Consequently, a study of the impact of this functionnal on electronic properties of cuprates is conducted. The chapter is ended by an article treating magnetic orders in doped La 2CuO4. Supplementary materials of the second article and a description of the theory of superconductivity of Bardeen, Cooper and Schrieffer are put in annex. Keywords : Electronic correlation, DFT, LDA+U, cuprates, polymers, magnetic orders

  7. Mise en évidence de fortes circulations verticales temporaires entre zones humides et aquifères alluviaux et régionaux

    NASA Astrophysics Data System (ADS)

    Weng, Philippe; Coudrain-Ribstein, Anne; Kao, Cyril; Bendjoudi, Hocine; Marsily, Ghislain de

    1999-08-01

    Tensiometric and piezometric values were recorded in an alluvial valley of the Seine wetland from February to November 1998. As a consequence of two flood events, the groundwater head once rose above the soil surface. When the water level in the Seine decreased, the vertical hydraulic gradient between the underlying Senonian chalk and the alluvia increased to 16 %o. During the few days of recession the alluvial wetlands were fed by an upward flow from the regional chalk aquifer and drained towards the river through a more permeable alluvial layer (1.5 m to 7 m below soil surface).

  8. Associação entre lipid accumulation product (LAP) e hirsutismo na síndrome do ovário policístico.

    PubMed

    Oliveira, Flávia Ribeiro de; Rezende, Mariana Bicalho; Faria, Nícolas Figueiredo; Dias, Tomás Ribeiro Gonçalves; Oliveira, Walter Carlos Santos de; Rocha, Ana Luiza Lunardi; Cândido, Ana Lúcia

    2016-02-01

    Objective Polycystic ovary syndrome (PCOS) is the most common endocrine metabolic disorder in women between menarche and menopause. Clinical hyperandrogenism is the most important diagnostic criterion of the syndrome, which manifests as hirsutism in 70% of cases. Hirsute carriers of PCOS have high cardiovascular risk. Lipid accumulation product (LAP) is an index for the evaluation of lipid accumulation in adults and the prediction of cardiovascular risk. The aim of this study was to evaluate the association between LAP and hirsutism in women with PCOS. Methods This was a cross-sectional observational study of a secondary database, which included 263 patients who had visited the Hyperandrogenism Outpatient Clinic from November 2009 to July 2014. The exclusion criteria were patients without Ferriman-Gallwey index (FGI) and/or LAP data. We used the Rotterdam criteria for the diagnosis of PCOS. All patients underwent medical assessment followed by measurement and recording of anthropometric data and the laboratory tests for measurement of the following: thyroid-stimulating hormone, follicle-stimulating hormone, prolactin, total testosterone, sex hormone binding globulin, 17-α-hydroxyprogesterone (follicular phase), glycohemoglobin A1c, and basal insulin. In addition, the subjects underwent lipid profiling and oral glucose tolerance tests. Other laboratory measurements were determined according to clinical criteria. LAP and the homeostatic model assessment index (HOMA-IR) were calculated using the data obtained. We divided patients into two groups: the PCOS group with normal LAP (< 34.5) and the PCOS group with altered LAP (> 34.5) to compare the occurrence of hirsutism. For statistical analysis, we used SPSS Statistics for Windows® and Microsoft Excel programs, with descriptive (frequencies, percentages, means, and standard deviations) and comparative analyses (Student's t-test and Chi-square test). We considered relations significant when the p-value was ≤ 0.05. Results LAP was high in most patients (n = 177; 67.3%) and the FGI indicated that 58.5% of the patients (n = 154) had hirsutism. The analysis by LAP quartiles showed a positive correlation (p = 0.04) among patients with a high FGI and an upper quartile LAP (> 79.5) when compared with those with LAP < 29.0 (lower quartile). Conclusion This study demonstrated an association between high LAP and hirsutism. The FGI could represent a simple and low-cost tool to infer an increased cardiovascular risk in women with PCOS. PMID:26909772

  9. L'Alternance entre les auxiliaires "avoir" et "etre" en francais parle a Montreal (Alternation between the Auxiliaries "Avoir" and "Etre" in Spoken French in Montreal)

    ERIC Educational Resources Information Center

    Sankoff, Gillian; Thibault, Pierrette

    1977-01-01

    A study of the spoken French of 120 residents of Montreal. The researchers were interested in the linguistic and social factors influencing the use of "avoir" and "etre." Results show that this usage corresponds to a tendancy to regularize conjugations. (Text is in French.) (AMH)

  10. Entre dicho y hecho ...: An Assessment of the Application of Research from Second Language Acquisition and Related Fields to the Creation of Spanish CALL Materials for Lexical Acquisition

    ERIC Educational Resources Information Center

    Lafford, Barbara A.; Lafford, Peter A.; Sykes, Julie

    2007-01-01

    Despite the problems presented by lexical errors in second language (L2) communication, most computer assisted language learning (CALL) programs tend to focus on the acquisition of grammar points rather than on the development of the L2 lexicon. In addition, CALL vocabulary tasks are typically limited in scope and mechanical in nature, covering…

  11. Católicos, fidelidade conjugal e AIDS: entre a cruz da doutrina moral e as espadas do cotidiano sexual dos adeptos1

    PubMed Central

    Rios, Luis Felipe; de Aquino, Francisca Luciana; Muñoz-Laboy, Miguel; Oliveira, Cinthia; Parker, Richard

    2009-01-01

    Neste artigo discutimos a visão da Igreja Católica sobre sexualidade na interface com a epidemia do HIV/AIDS. Nossa reflexão está embasada em pesquisa etnográfica que envolveu dois meses de observação participante do cotidiano de católicos de um bairro popular da Região Metropolitana do Recife, além de contar com entrevistas a onze dos leigos engajados nos serviços religiosos da igreja do bairro e a oito sacerdotes que realizam seus trabalhos religiosos em outras localidades. Nelas abordamos diferentes temáticas relacionadas ao enfrentamento da epidemia da AIDS. Nesse contexto, conjugalidade e fidelidade se afiguram como importantes analisadores de como aqueles lidam com a epidemia, em uma variedade de re-descrições práticas e de re-interpretações conceptuais das assertivas do discurso moral religioso – ainda que, muitos impasses permaneçam em aberto em termos das prerrogativas da Igreja e seus possíveis rebatimentos na saúde sexual dos adeptos. PMID:21765650

  12. En la búsqueda de características en eyecciones coronales de masa que discriminen entre dos paradigmas físicos en modelos de ECMs

    NASA Astrophysics Data System (ADS)

    Paissan, G.; Stenborg, G.; Rovira, M.

    Se conocen tres diferentes fenómenos de gran escala que ocurren en la atmósfera solar, denominados eyecciones coronales de masa (ECMs), protuberancias eruptivas y grandes fulguraciones de dos bandas. Estos fenómenos están estrechamente relacionados y podrían ser distintas manifestaciones de un único proceso físico. Las ECMs son definidas como eyecciones de gran escala de masa y flujo magnético desde la baja corona al espacio interplanetario. Desde su descubrimiento en los '70, muchos modelos han sido propuestos para explicar su origen y evolución. La explicación física de las ECMs es un tema de debate intenso. No obstante, los modelos pueden sintetizarse en dos grandes grupos: 1) los modelos de inyección de flujo y 2) los modelos de almacenamiento y liberación. En este trabajo, se presentan los estudios realizados con una serie de eventos observados con el coronógrafo MICA (Mirror Coronograph for Argentina), el telescopio en H-alfa HASTA (H-alpha Solar Telescope for Argentina) y los coronógrafos C2 y C3 de la sonda SOHO (Solar and Heliospheric Observatory). Los eventos que pudieron ser identificados como ECMs son contrastados dentro del esquema de los dos paradigmas teóricos propuestos.

  13. La preparacion del maestro y la interaccion entre maestro y nino en programas preescolares (Teacher Preparation and Teacher-Child Interaction in Preschools). ERIC Digest.

    ERIC Educational Resources Information Center

    Kontos, Susan; Wilcox-Herzog, Amanda

    It is generally agreed that because so much basic early learning occurs through interactive experiences when children are very young, the quality of teacher-child interactions contributes substantially to effects of group care and preschool education on children. Thus it is important to know if specialized teacher education in early childhood…

  14. Transitioning to new child-care nutrition policies: nutrient content of preschool menus differs by presence of vegetarian main entrée.

    PubMed

    Turner-McGrievy, Gabrielle M; Hales, Sarah B; Baum, Angela C

    2014-01-01

    Children who attend child care outside the home may be at increased risk for developing obesity. In 2012, the South Carolina ABC Child Care program issued new standards for food and nutrition. The goal of our study (conducted June to December 2012) was to examine changes that occurred at a large, Columbia, SC, preschool during the implementation of the South Carolina ABC Child Care program standards using an observational design, including a survey of parents and nutrient analysis of menus. The nutrition content of menu items before (n=15 days; six of which were vegetarian) and after (n=15 days; six of which were vegetarian) implementation of the new standards was compared. In addition, parents (N=75) were surveyed to examine opinions and support for the changes. Independent samples t tests were used to compare nutrient values before and after menu changes and analysis of variance was used to compare pre- and post-change vegetarian menus and pre- and post-change nonvegetarian menus. There were no significant differences between before and after menus with the exception of a 0.3 cup/day increase in vegetables (P<0.05). Vegetarian menus after the revisions were significantly higher in fiber (13 ± 3 g) than postrevision nonvegetarian menus (11 ± 3 g; P<0.05) and lower in sodium (1,068 ± 207 mg) than postrevision nonvegetarian menus (1,656 ± 488 mg; P<0.05). Standards that received the most parental support were serving at least two vegetables (score of 8.7 on a scale of one to nine) and two fruits per day (score of 8.6) and implementing policies against staff using food as a reward or punishment (score of 8.6). The center-specific policy of only bringing healthy foods for celebrations received the lowest support (score of 5.8). Adding more vegetarian menu items has the potential to improve the nutrient content of menus while keeping energy intake, saturated fat, sodium, and cholesterol levels at a more optimum level. PMID:24144990

  15. Etude comparative entre l'astrolabe dit "carolingien" et l'astrolabe d'Abù-Bakr ibn Yusuf de Toulouse.

    NASA Astrophysics Data System (ADS)

    D'Hollander, R.

    This article is a comparative study that is essentially technical. It is based on very careful measurements of an accuracy of up to one tenth of a millimetre carried out on the plates and retes of the two astrolabes examined by the writer. Abù-Bakr ibn Yusuf's astrolabe is in the Musée Paul Dupuy in Toulouse. It was made in 1216-17 in Marrakech.

  16. Relationship between Emotional Intelligence and Mental Health in School Counselors (Relación entre Inteligencia Emocional y salud mental en Orientadores Educativos)

    ERIC Educational Resources Information Center

    Cejudo, Javier

    2016-01-01

    Introduction: The purpose of the present research is aimed at studying the relationship between emotional intelligence as an ability and emotional intelligence as a trait and mental health of a sample of school counsellors. Method: The sample has been made up of 203 school counsellors. The instruments used have been: Mayer-Salovey-Caruso Emotional…

  17. Psychological Correlates of the Transmission and Acceptance of Rumors about AIDS = Correlates Psychologiques Entre la Transmission et l'Acceptation des Rumeurs sur le SIDA.

    ERIC Educational Resources Information Center

    Kimmel, Allan J.

    Public reactions to the Acquired Immune Deficiency Syndrome (AIDS) crisis are accompanied by the sorts of emotional and cognitive factors that have been identified by researchers as predictors of rumor generation and transmission. The present investigation attempted to ascertain the extent that various subjective factors (including anxiety,…

  18. Uma comparação entre técnicas de propagação de erros em astrofísica: Monte Carlo x Bootstrap

    NASA Astrophysics Data System (ADS)

    Waelkens, A. H.; Janot Pacheco, E.

    2003-08-01

    Recentemente Dhillon & Watson (2001) criticaram o procedimento de determinação de erros via simulações de Monte Carlo no caso do imageamento indireto de estrelas, por introduzir ruído nos dados e resultar em erros superestimados. Estes autores propuseram a utilização alternativa do método de Bootstrap como uma técnica superior para a estimativa de erros. Neste trabalho apresentamos os resultados de um estudo comparativo da performance das técnicas de simulação por Monte Carlo e por Bootstrap para a determinação de erros em duas situações de interesse: (i) ajuste de modelos a espectros observados e (ii) imageamento indireto de discos de acréscimo com técnicas de mapeamento por eclipse. No caso (i), os dados de entrada são espectros de emissão simples de hidrogênio aos quais é adicionado ruído gaussiano de amplitude selecionada. No caso (ii), são produzidas curvas de luz do eclipse de uma distribuição de brilho seguindo a lei TµR-3/4 para discos estacionários cuja taxa de acréscimo varia ao longo do eclipse segundo uma distribuição gaussiana de amplitude selecionada, simulando o ruído. A avaliação da performance é feita com o auxílio de um diagrama do erro relativo na grandeza ajustada, conforme obtido por cada método, versus o erro relativo (ruído/sinal) dos dados de entrada. O estudo mostra que as duas técnicas produzem resultados semelhantes nos dois casos, e que a suposta superioridade do método de Bootstrap não se confirma.

  19. Origine physique du contraste entre activité électrique au dessus des terres et des océans

    NASA Astrophysics Data System (ADS)

    Williams, Earle; Stanfill, Sharon

    2002-12-01

    New tests and older ideas are explored to understand the origin of the pronounced contrast in lightning between land and sea. The behavior of islands as miniature continents with variable area supports the traditional thermal hypothesis over the aerosol hypothesis for lightning control. The substantial land-ocean contrast in updraft strength is supported globally by TRMM (Tropical Rainfall Measuring Mission) radar comparisons of mixed phase radar reflectivity. The land-ocean updraft contrast is grossly inconsistent with the land-ocean contrast in CAPE (Convective Available Potential Energy), from the standpoint of parcel theory. This inconsistency is resolved by the scaling of buoyant parcel size with cloud base height, as suggested by earlier investigators. Strongly electrified continental convection is then favored by a larger surface Bowen ratio, and by larger, more strongly buoyant boundary layer parcels which more efficiently transform CAPE to kinetic energy of the updraft in the moist stage of conditional instability. To cite this article: E. Williams, S. Stanfill, C. R. Physique 3 (2002) 1277-1292.

  20. Relación física entre el cúmulo abierto Hogg 15 y la estrella Wolf-Rayet WR 47

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Bica, E.; Santos, J. F. C., Jr.; Clariá, J. J.

    We revise the fundamental parameters of the faint open cluster Hogg 15, for which two recent colour-magnitude diagram (CMD) studies have obtained significantly different ages (Sagar et al. 2001, MNRAS, 327, 23; Piatti & Clariá 2001, A&A, 370, 931). In the present study, we combine a series of methods trying to constrain age, together with other fundamental parameters. We employ spatial extractions to construct the CMDs, and the cluster integrated spectrum to compare the latter with those of templates of known age. For Hogg 15 we derive an age of (20 ± 10) Myr, a reddening of (1.10 ± 0.05) mag, and a distance of (3.1 ± 0.5) kpc. We conclude that the estimation of an older age in the study of Piatti & Clariá can be accounted for in terms of main sequence/turnoff curvature being blurred in the CMDs, an effect mainly caused by field contamination. To clarify the issue of whether the Wolf-Rayet star HDE 311884 (WR 47), known to be a WN6 + O5V binary system, is associated or not with Hogg 15, we discuss its fundamental parameters, particularly its distance. Based on the WR 47 spectrum and available photometry, we assume that the underestimated distance implied by the Hipparcos parallax (216 pc) is affected by its binary character. By comparing the WR 47 spectrum with those of WR stars of a similar type, we conclude that WR 47 is not affected by a E(B-V) colour excess much higher than that associated with Hogg 15, namely E(B-V) = 1.10. On the basis of the WR 47's resulting distance of (5.2 ± 0.9) kpc, which largely surpasses that of the cluster, we conclude that WR 47 is not related to Hogg 15 from the point of view of origin, since the cluster and the star do not belong to the same formation event.

  1. Vinculación Física entre Super Cáscaras de Hidrógeno Neutro y Formación Estelar Reciente

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Arnal, E. M.

    Many of the known galactic HI supershells (SCHI) may have been formed by the combined effects of stellar winds and supernovae explotions. Having most of them dynamic lifetimes of a few times 10^7 yr, these huge structures are likely to outlive the stars that gave rise to them. Hence, these SCHI may be used as fossil records of the Milky Way star formation history. Furthermore, along their evolution SCHI may trigger star formation. In this paper we analyze the genetic link put forward by McClure-Griffiths et al. (2002) between the OB association Cen OB1 and the SCHI GSH305+01-24. From our study we conclude that GSH305+01-24 may not represent a real physical structure. Instead, we believe that this structure is best represented by two unrelated huge HI shells. The role played by Cen OB1 in powering one of these HI shells is unclear for the time being. FULL TEXT IN SPANISH.

  2. Denomination et categorisation des modeles d'enseignement des langues: entre institution et pratique (Denomination and Categorization of Language Teaching Models: Between Institution and Practice).

    ERIC Educational Resources Information Center

    Gajo, Laurent; Matthey, Marinette

    1998-01-01

    The process and issues of labeling language program models is discussed insofar as it may affect the objectives, content, and method of instruction. The first section describes the origins, stated objectives, and implementation of a Neuchatel (Switzerland) school program integrating heritage language and culture into the school curriculum, noting…

  3. L'espace du mouvement: Une analyse des conflits dans les interactions entre institutrice et eleves d'une ecole maternelle

    NASA Astrophysics Data System (ADS)

    Galvão, Izabel

    1995-01-01

    The research described in this article, winner of the Gottfried Hausmann Prize for 1994, was carried out in a kindergarten in São Paolo, Brazil, using the theory developed by Henri Wallon. The aim was to examine how primary school children are affected in their development by: (a) unnecessary restrictions placed on their physical movements during lessons; and (b) failure to organize the classroom space in a way that assists the learning process. The author concludes that these factors lead to tensions in the classroom which could be avoided through a different approach to movement and space.

  4. Make the Reading-Writing Connection: Tips for Parents of Young Learners = Haga el enlace entre lectura y escrita: Consejos para padres de jovenes que estan aprendiendo.

    ERIC Educational Resources Information Center

    International Reading Association, Newark, DE.

    This brochure offers parents tips on helping their children connect writing with reading. It begins by noting that preschool children often want to scribble on paper, scribbles which sometimes represent a story. It suggests making space in the home for literacy, and encouraging early efforts. The brochure then offers four brief activities for…

  5. Previniendo el Uso de Drogas entre Ninos y Adolescentes: Una Guia Basada en Investigaciones (Preventing Drug Use among Children and Adolescents: A Research-Based Guide).

    ERIC Educational Resources Information Center

    Sloboda, Zili; David, Susan L.

    This question and answer guide provides an overview of the research on the origins and pathways of drug abuse, the basic principles derived from effective drug abuse prevention research, and the application of research results to the prevention of drug use among young people. The basic principles derived from drug abuse prevention research are…

  6. Thriving Together: Connecting Rural School Improvement and Community Development = Prosperando juntos: La conexion entre el mejoramiento de la escuela rural y el desarrollo comunitario.

    ERIC Educational Resources Information Center

    Boethel, Martha

    Available in English or Spanish, this resource guide aims to help rural schools and communities learn ways of supporting each other so that both can thrive. Background information and basic tools are provided for starting a joint school-community development effort. Chapters contain: (1) outline of the guide and statement of beliefs about…

  7. The Effect of Low Dose Irradiation and Grapefruit Extract on C. perfringens Growth from Spores in sous vide Processed Pork-Based Mexican Entrée

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sous vide, a common cooking method for meat and poultry products is widely used for providing ready-to-eat meals. Traditionally, these products have limited shelf life, ranging from 2 to 3 weeks. However, similar products may be stored for longer periods in the U.S. and other countries, requiring ad...

  8. Relación entre la orientación de Nebulosas Planetarias y el campo magnético galáctico

    NASA Astrophysics Data System (ADS)

    Weidmann, W.; Díaz, R. J.; Carranza, G.

    Un estudio detallado de las orientaciones diferenciales de nebulosas planetarias en todo el cielo sugiere fuertemente una relación con la dirección de los campos magnéticos de origen galáctico, determinados en la polarización de estrellas de campo. Esto da consistencia a la hipótesis de que la orientación de las nebulosas planetarias ovaladas es inducida, al menos parcialmente, por el campo magnético general de la Vía Láctea.

  9. Contribution à l'analyse des inter-relations entre activités humaines et variabilité climatique : cas du Sud forestier ivoirien

    NASA Astrophysics Data System (ADS)

    Yao, Télésphore Brou; Servat, Eric; Paturel, Jean-Emmanuel

    1998-12-01

    The South Ivorian Forest has suffered a large rainfall deficit for 25 years. At the same time, it has been noticed that the movement of the coffee and cocoa production seems concomitant with that of the isohyets during recent decades. The variations in albedo and rainfall gradient seem to be linked to the significant changes to the forest cover. These could affect precipitation locally.

  10. Trait differences between naturalized and invasive plant species independent of residence time and phylogeny

    PubMed Central

    Gallagher, R V; Randall, R P; Leishman, M R

    2015-01-01

    inclusion of quantitative traits, in particular SLA, into the WRA schemes. Diferencia de Características entre Especies de Plantas Naturalizadas e Invasoras Independientes del Tiempo de Residencia y de la Filogenia Resumen La habilidad para predecir cuáles plantas exóticas harán la transición de naturalizadas a invasoras antes de su introducción a regiones nuevas es un objetivo clave para la conservación y tiene el potencial de incrementar la eficiencia de la evaluación de riesgo de hierbas (ERH). Sin embargo, múltiples factores contribuyen al éxito invasor de las plantas (p. ej.: características funcionales, características de cobertura, tiempo de residencia, filogenia) y todos deben considerarse simultáneamente para poder identificar correlaciones significativas del éxito invasor. Recopilamos en Australia 146 parejas de especies de plantas invasoras y naturalizadas emparejadas filogenéticamente (congéneres) y con tiempos de residencia mínima similares (es decir, el tiempo transcurrido desde su introducción en años). Estas parejas se usaron para probar diferencias en cinco características funcionales (duración de la floración, tamaño de la hoja, altura máxima, área específica de la hoja [AEH], masa de la semilla) y en tres características de cobertura nativa de las especies (ocupación de bioma, temperatura media anual y amplitud de pluviosidad) entre especies invasoras y naturalizadas. Las especies invasoras, en promedio, tuvieron una mayor AEH, periodos de floración más largos y fueron más altas que sus parientes congéneres naturalizadas. Las invasoras también exhibieron una mayor tolerancia a diferentes condiciones ambientales en su cobertura nativa, donde ocuparon más biomas y una mayor amplitud de pluviosidad y condiciones de temperatura que sus congéneres naturalizadas. Sin embargo, ni la masa de la semilla ni el tamaño de hoja difirieron entre las parejas de especies naturalizadas e invasoras. Un hallazgo relevante fue el papel de

  11. When Did the Swahili Become Maritime?

    PubMed Central

    Fleisher, Jeffrey; Lane, Paul; LaViolette, Adria; Horton, Mark; Pollard, Edward; Quintana Morales, Eréndira; Vernet, Thomas; Christie, Annalisa; Wynne-Jones, Stephanie

    2015-01-01

    esta sociedad costera entre el primer y segundo milenio. Éstas son la variabilidad y discontinuidad en la localización y permanencia de los asentamientos; evidencia de una conexión mayor con el mar a través de la tecnología de pesca y navegación; y desarrollos arquitectónicos especializados que incluyen instalaciones portuarias, mezquitas, y casas. Las implicaciones de este estudio indican que debemos considerar otros aspectos de una sociedad aparte de su localización costera para determinar su maritimidad. Hay que considerar cómo el mar y sus productos son parte de la vida social y evaluar si existe una influencia recíproca entre el ambiente marítimo y los patrones de organización sociocultural, las prácticas, y las creencias de los Swahili y otras sociedades. [marítimo, pesca y navegación, comercio a larga distancia, Swahili, África Oriental] PMID:25821235

  12. Estudio de la influencia de la refrigeracion con aire de forma natural e inducida en el comportamiento de instalaciones fotovoltaicas

    NASA Astrophysics Data System (ADS)

    Mazon Hernandez, Rocio

    panels are analysed to compare and select the best configuration. The presented research provides a deep knowledge of how they work as well as information and results for an improvement in future designs of building integrated photovoltaic systems. Este estudio se centra en analizar la influencia negativa de la temperatura en la produccion electrica de paneles fotovoltaicos al estar emplazados sobre cubierta de acero, como sucede en naves industriales y sobre un invernadero. Se estudian diferentes configuraciones que permitan refrigerar los paneles, reduciendo su temperatura y mejorar su rendimiento. Para abordar este problema, se han construido dos instalaciones experimentales, fieles a plantas solares en funcionamiento. Una instalacion engloba dos paneles fotovoltaicos sobre estructura fija al suelo. Uno de los paneles esta integrado sobre una superficie paralela y metalica. Entre ambas superficies existe un espacio que posibilita circular aire, permitiendo refrigerar el panel por conveccion natural, o conveccion forzada impulsando el aire con un ventilador. El otro panel, libre por su cara posterior y se ha considerado de referencia. Se ha estudiado el comportamiento del panel integrado sobre cubierta para diferentes secciones de aire y velocidades inducidas, comparandolo con el panel de referencia. Se ha desarrollado un modelo experimental que nos permite determinar la temperatura del panel en funcion de las variables que influyen en su refrigeracion. Adicionalmente, se han analizado los datos de una planta solar en funcionamiento, con paneles de igual caracteristicas, obteniendo correlaciones entre la temperatura del panel y las variables electricas y comparandolos con las obtenidas en la instalacion experimental. La segunda instalacion experimental reproduce parte de una instalacion solar sobre un invernadero, formada por cuatro paneles fotovoltaicos colocados sobre el plastico del invernadero, existiendo un canal divergente entre ambas superficies. Se estudia la

  13. CONTAMINACIÓN AMBIENTAL, VARIABILIDAD CLIMÁTICA Y CAMBIO CLIMÁTICO: UNA REVISIÓN DEL IMPACTO EN LA SALUD DE LA POBLACIÓN PERUANA

    PubMed Central

    Gonzales, Gustavo F.; Zevallos, Alisson; Gonzales-Castañeda, Cynthia; Nuñez, Denisse; Gastañaga, Carmen; Cabezas, César; Naeher, Luke; Levy, Karen; Steenland, Kyle

    2015-01-01

    RESUMEN El presente artículo es una revisión sobre la contaminación del agua, el aire y el efecto del cambio climático en la salud de la población peruana. Uno de los principales contaminantes del aire es el material particulado menor de 2,5 μ (PM 2,5), en la ciudad de Lima, anualmente 2300 muertes prematuras son atribuibles a este contaminante. Otro problema es la contaminación del aire domiciliario por el uso de cocinas con combustible de biomasa, donde la exposición excesiva a PM 2,5 dentro de las casas es responsable de aproximadamente 3000 muertes prematuras anuales entre adultos, con otro número desconocido de muertes entre niños debido a infecciones respiratorias. La contaminación del agua tiene como principales causas los desagües vertidos directamente a los ríos, minerales (arsénico) de varias fuentes, y fallas de las plantas de tratamiento. En el Perú, el cambio climático puede impactar en la frecuencia y severidad del fenómeno de El Niño oscilación del sur (ENSO) que se ha asociado con un incremento en los casos de enfermedades como cólera, malaria y dengue. El cambio climático incrementa la temperatura y puede extender las áreas afectadas por enfermedades transmitidas por vectores, además de tener efecto en la disponibilidad del agua y en la contaminación del aire. En conclusión, el Perú, pasa por una transición de factores de riesgo ambientales, donde coexisten riesgos tradicionales y modernos, y persisten los problemas infecciosos y crónicos, algunos de los cuales se asocian con problemas de contaminación de agua y de aire. PMID:25418656

  14. Farmyard Manure and Fertilizer Effects on Seed Potato (Solanum tuberosum L.) Yield in Green House Production

    NASA Astrophysics Data System (ADS)

    László, M.

    2009-04-01

    alta potencialidade (boa textura e adequada retenção de agua). Efeito do nitrogênio No Brazíl em todas regiões onde se cultiva batata é raro encontrar solos com elevado teor de nitrogênio e que não precisam de quantidades desta elemento. É o elemento que governa o padrão de desenvolvimento da planta, estimulando principalmente o crescimento da parte aérea (Kádár et all. 2000., László 2000.). Para se obter rendimento de tubérculos é necessário um rápido e curto periodo de desenvolvimento da parte aérea e uma fase de acúmulo maior possível. Para tanto, devem ser evitadas doses muito altas de nitrogênio e, principalmente, se aplicadas tardiamente, pois haverá demasiado desenvolvimento de folhas que demorarão mais a finalizar seu crescimento e maturação. Isto implicará na redução do periodo de intenso desenvolvimento dos tubérculos e armazenagem do amido, resultando em menor produção. Há risco para a saúde na ingestão de alimentos com altos teores de nitrato e nitrito, havendo preocupação com o efeito de doses mais altas de nitrogênio sobre os teores dos mesmos nos tuberculos. Embora haja diferenças entre cultivares, localidades e períodos de armazenamento, há estudos mostrando que a fertilização com até 150 kg ha-1 de nitrogênio não foi suficiente para propiciar niveis preocupantes de nitrato nos tuberculos colhidos. Efeito do fósforo A grande maioria dos solos brasileiros cultivados com batata apresentam limitações ao bom desenvolvimento e produção da cultura em função dos baixos níveis de fósforo. Isto significa que aumentos de produção quase sempre ocorrem quando o solo recebe adubação fosfatada (László 2001a.). Estes aumentos são mais marcantes em solos nunca antes adubados ou com baixo teor de fósforo. Nestes, dificilmente alcanca- se a produção máxima com níveis reduzidos de fósforo. Não seria exagerado supor níveis de 600 a 800 kg ha-1 de P2O5, como sendo aqueles que iriam proporcionar produ

  15. Cinématique des failles entre les unités subbétiques pendant le Miocène (secteur central de la cordillère Bétique).

    NASA Astrophysics Data System (ADS)

    Galindo-Zaldívar, Jesús; Ruano, Patricia; Jabaloy, Antonio; López-Chicano, Manuel

    2000-12-01

    The kinematic analysis of the low-angle faults that separate the major units of the Subbetic Zone indicates two main stages of translations. In the first stage, of Burdigalian to basal Tortonian age, the hanging walls moved toward the WSW, and thrusts developed in some sectors of the External Zones. Simultaneously, in the Internal Zones, the activity of extensional detachments shows the same kinematics. In the second stage, affecting up to basal Tortonian rocks, northwest-verging thrusts were active. The Subbetic tectonic units probably underwent relative rotation during the development of these structures.

  16. A Comparison of Chinese and Colombian University EFL Students Regarding Learner Autonomy (Comparación entre estudiantes universitarios de inglés chinos y colombianos con respecto a su autonomía como aprendices)

    ERIC Educational Resources Information Center

    Buendía Arias, Ximena Paola

    2015-01-01

    This research seeks to gain deeper understanding of learner autonomy in English as a Foreign Language students from different cultures through the identification and analysis of similarities and differences between Chinese and Colombian students from two public universities: Tianjin Foreign Studies University in China and Universidad Surcolombiana…

  17. Corrélations entre propriétésélectriques et structurales de solutions solides de type fluorinea`exce`s d'anions: Essai de mode`lisation

    NASA Astrophysics Data System (ADS)

    Reau, J. M.; Senegas, J.; El Omari, M.

    1990-02-01

    In a fluoride ion excess CaF 2-type solid solution of formulation M 2+1-xM' 2+αxF 2+αx (α = 1, 2, 3) , the sum of the interstitial fluoride ions n F int and the sum of the vacancies in normal sites n □ can be represented according to general equations y = (mx 3 + λqx)(x 2 + q) : the m and λ parameters depend on structural features, and q is bound to electrical properties. This model allows one to correlate in a continuous way the composition dependence of electrical properties and the progressive extension of clusterization when the substitution rate increases.

  18. [The EMECAM project: a discussion of the results in the participating cities. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica y la Mortalidad].

    PubMed

    Ballester Díez, F; Sáez Zafra, M; Pérez-Hoyos, S; Daponte Codina, A; Bellido Blasco, J B; Cañada Martínez, A; Abad Díez, J M; Pérez Boíllos, M J; Alonso Fustel, M E; Taracido Trunk, M; Aguinaga Ontoso, I; Guillén Pérez, J J; Ordóñez Iriarte, J M; Saurina Canals, C; Tenías Burillo, J M

    1999-01-01

    This article draws a comparison and provides a discussion of the findings resulting from the local analyses of the 14 cities participating in the EMECAM Project. An analysis is made of the time series related to mortality, pollutants (particles in suspension, SO2, NO2, O3 and CO), temperature and other factors taken from records of public institutions. By using Poisson autoregressive regression, an estimate has been made of the short-term relationship between the number of deaths and the air pollution indicators in each one of the following cities: Barcelona, metropolitan area of Bilbao, Cartagena, Castellón, Gijón, Huelva, Madrid, Pamplona, Seville, Oviedo, Valencia, Vigo, Vitoria and Saragossa. The findings reveal the air pollution figures in our country to be similar to those of other European cities. The levels of the different pollutants point toward road traffic as being the main source of most of this pollution. A relationship has been found between the mortality and different pollutants in most cities, although the results are not homogeneous among the cities and show variability in the different causes under study. In some cities, especially in those having smaller populations, there have been no findings providing any evidence of a relationship, or the findings themselves are not highly consistent. The meta-analysis will provide estimates for all of the cities as a whole and will allow the possibility of making a more clear-cut assessment of the time lag impact of air pollution on the mortality. Worthy of special mention is the participation in this project of public health officers as actively involved researchers. PMID:10410614

  19. Repertoire de didacticiels de francais langue seconde ou etrangere publies entre 1980 et 1988 (List of Courseware for French as a Second or Foreign Language Published between 1980 and 1988). Publication K-11.

    ERIC Educational Resources Information Center

    H.-Lemonnier, France; And Others

    A listing of 97 items of courseware includes programs in seven categories, pertaining to: (1) vocabulary; (2) grammar; (3) verb conjugation; (4) syntax and/or morphosyntax; (5) reading and/or writing; (6) oral language; and (7) other areas of French second language instruction. Each citation includes the title, program type (e.g. drill, game),…

  20. Exploring Elementary Students' Power and Solidarity Relations in an EFL Classroom (Exploración de las relaciones de poder y solidaridad entre estudiantes de primaria en la clase de inglés como lengua extranjera)

    ERIC Educational Resources Information Center

    Méndez, Tatiana; García, Andrea

    2012-01-01

    This article derives from a critical discourse analysis study that reports the characteristics of elementary school students' power and solidarity relations in English as a foreign language classroom in Bogotá, Colombia, while we were doing our teaching English as a foreign language practicum. The study was based on theories of power and…

  1. Como ayudar a su hijo durante los primeros anos de la adolescencia: Para los padres con ninos entre las edades de 10 a 14 anos (Helping Your Child through Early Adolescence: For Parents of Children from 10 through 14).

    ERIC Educational Resources Information Center

    Paulu, Nancy

    Recognizing that parents and families can greatly influence the development of their 10- through 14-year-olds, this Spanish-language booklet is part of a national effort to provide parents with the latest research and practical information to help them support their children both at home and in school. The booklet is organized in 13 sections…

  2. La Desercion Escolar en los Niveles de Sexto y Noveno Grado: Una Comparacion Entre Zonas Rurales y Urbanas. Boletin 219 (The Educational Desertion in the 6th and 9th Grades: A Comparison Between Rural and Urban Zones. Bulletin 219).

    ERIC Educational Resources Information Center

    Lopez, Maria I. Hernandez; And Others

    In 1962 and again in 1965, a group of sixth and ninth grade students in selected schools in four Puerto Rican communities were interviewed to investigate the factors influencing students' decision to withdraw from school before completing twelfth grade and to identify some characteristics of dropouts. Of 616 students interviewed in 1962, 20.9% of…

  3. Teacher Collaboration Praxis: Conflicts, Borders, and Ideologies from a Micropolitical Perspective (La práctica colaborativa entre docentes: conflictos, fronteras e ideologías desde una perspectiva micropolítica)

    ERIC Educational Resources Information Center

    Keranen, Nancy; Encinas Prudencio, Fátima

    2014-01-01

    This paper looks at a feature of teacher collaboration within Achinstein's (2002) micropolitics of collaboration but from an intrapersonal perspective. Results discussed feature issues of conflict, borders, and ideologies within each participating teacher rather than between teachers. Unresolved or unacknowledged intrapersonal conflict might lead…

  4. Suivis temporels comparés de la structure thermique d'eaux côtières libanaises (Batroun) et françaises (Marseille) entre juin 1999 et octobre 2002

    NASA Astrophysics Data System (ADS)

    Abboud-Abi Saab, Marie; Romano, Jean-Claude; Bensoussan, Nathaniel; Fakhri, Milad

    2004-11-01

    Vertical temperature profiles were recorded from June 1999 to October 2002 (at least once a month) at two Mediterranean sites, in the eastern basin (Batroun, Lebanon; 0-100 m) and in the northwestern basin (Marseilles, France; 0-55 m). At the two sites, the thermal seasonal evolution and the thermocline time dynamics are quite identical. But in the Lebanese waters, at comparable water depths, temperatures are currently 4 to 5 °C higher than in the French waters, the thermocline is longer (more than 6 months), permanent and deeper (40-50 m) than in Marseilles (20-30 m). The latter frequently disappears in summer due to northwest winds inducing cold waters. This is principally due to differences in prevailing wind regimes at each site. Such evaluation, coupled with long-term observations of temporal evolution of coastal water at the regional level of the Mediterranean basins, will shed light on temperature regime fluctuations and their consequences in the context of global warming of the Mediterranean. To cite this article: M. Abboud-Abi Saab et al., C. R. Geoscience 336 (2004).

  5. Vinculos Entre la Capacitacion de Docentes y el Desarrollo de Materiales Educativos Impresos--Anotaciones para Una Discusion (Links between In-service Teacher Training and the Development of Printed Educational Aids).

    ERIC Educational Resources Information Center

    Valle, Victor M.

    Textbooks and other printed materials will be ever present, in the foreseeable future, as major aids for teaching and learning processes. New textbooks imply new guidelines for teachers, and the ways to handle such guidelines demand teacher training. This paper explains some links between inservice teacher training programs and the development of…

  6. Adequation between environmental shifts and human speciations during the Plio-PleistoceneAdéquation entre changements environnementaux et spéciations humaines au Plio-Pléistocène

    NASA Astrophysics Data System (ADS)

    Zeitoun, Valery

    2000-01-01

    Several synthetic studies provide evidence of faunistic and floristic shifts as consequences of global climatic events around 2.5 and 1.8 Ma. Some authors are more confident in the role played by local tectonic events to explain such a change in terms of vicariance. It is possible that astronomic, tectonic and climatic variations are linked, as the lithosphere is a catalyst for biosphere more or less strong according to the period. The purpose of this paper is to confront independent environmental and anatomical data to try to understand the evolutionary process in hominids, with particular emphasis on species of the genus Homo in East Africa during the Plio-Pleistocene period. Thus the result of a cladistic analysis based on 35 Otus and 468 features of the calvaria is showing the onset of at least four species to describe the grade of Homo habilis, living in East Africa. The radiation is congruent with the contemporaneous environmental shifts around 2.5 Ma, as is also the case for bovids or cercopithecids. Some Homo erectus left Africa when another climatic pulse happened around 1.8 Ma.

  7. Relaciones hidrogeologicas y medioambientales entre el mar mediterraneo, El saladar y el acuifero de agua amarga (provincia de alicante). Incidencia de las explotaciones de las desaladoras de alicante I Y II Y medidas correctoras

    NASA Astrophysics Data System (ADS)

    Manteca, Ivan Alhama

    The Agua Amarga coastal aquifer, located in the south of Alicante province, has been subjected to successive anthropogenic actions: salt works activity (1925-1975) and water withdrawal to supply the Alicante I and II desalination plants (since 2003). These interventions have influenced the salinity and the flow regime. Due to the existence of a salt marsh of ecological interest linked to the aquifer, the 'Mancomunidad de los Canales del Taibilla' (agency responsible for the desalination plants) designed a piezometric network for monitoring piezometry and electrical conductivity (in operation since May 2008). Soil humidity and piezometrics levels have been recovered by means of a seawater pouring programme over the salt marsh (since December 2009),which represents the third anthropic intervention. In this memoria, we investigate the Agua Amarga coastal aquifer to develop a physical conceptual model. Firstly, the study area is characterized in relation to climatology, geology, geomorphology and hydrogeology, using published information, describing, in addition, the desalination plants catchment system. Next, based on hydrogeological studies prior to the start up of the desalination plants, the aquifer is characterized: type, lithology, hydraulic parameters, thickness, surface extension, etc. Water quantity relating to rainfall, water withdrawal and pourings over the salt marsh, have been integrated in conjunction with data from monthly piezometric campaigns. In adittion, in order to gain insight into the groundwater mixing processes, chemical and isotope analyses were carried out on meteoric water and groundwater samples taken at different locations. The results were used to elaborate a conceptual physical model and a water budget. As an extension tool to understand processes and assess aquifer management, a 3-D fluid-flow and solute-transport model is designed with SEAWAT. Also, the 2-D physical characterization of scenarios with seawater intrusion and salt flats is presented. Finally, after describing ecological values of the salt marsh, the effect of the seawater pouring programme on aquifer piezometry and salinity is studied, assessing the possibility of applying this pilot scheme to other scenarios.

  8. Les "petits mots" de coordination: etude diachronique de leur apparition chez quatre enfants entre 3 et 4 ans (The "Little" Coordinating Words: A Diachronic Study of Their Appearance in Four Children, ages 3-4)

    ERIC Educational Resources Information Center

    Chambaz, Marcelle; And Others

    1975-01-01

    Reports on a diachronic study concerning the syntactic phenomena of coordination and subordination and their place in language acquisition. The organization and evolution of the coordination system of 4 children, ages 3-6 was studied. The need for investigation of adult speech for further understanding acquisition is stressed. (Text is in French.)…

  9. Etude de l'interface entre le profil psycho-spirituel des futurs maitres et le developpement psychosocial (Study of the Relationship between the Psycho-Spiritual Profile of Future Teachers and Their Psycho-Social Development).

    ERIC Educational Resources Information Center

    Michaud, Claude

    1996-01-01

    Describes a study examining the spiritual experiences among young adults in Ontario to help inform efforts to revise teacher education programs in Canada. Highlights the diversity of subjects' spiritual experiences and describes three typologies of individual spiritual development. Reviews the roles of the church, university, and school in teacher…

  10. Predictive Relationship between Humane Values of Adolescents Cyberbullying and Cyberbullying Sensibility (Relaciones predictivas entre los valores humanos de los adolescentes, el acoso cibernético y la sensibilidad al acoso cibernético)

    ERIC Educational Resources Information Center

    Dilmac, Bülent; Yurt, Eyüp; Aydin, Mustafa; Kasarci, Ismail

    2016-01-01

    Introduction: Cyberbullying has been more common than the traditional bullying in recent years. As with the traditional bullying, humane values likely to explain the reason why adolescents tend to bully via cyber-means. Cyber-bullying behaviors also reasoned by adolescents' sensibility towards it. This study investigates the predictive…

  11. Potencial de Seqüestro de Carbono Atmosférico entre Diferentes Cultivares de Milho (Zea mays L.) sob Condiç o de Déficit Hídrico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is a question concerning the role of agricultural practices on carbon sequestration enhancement. By producing biomass with agricultural crops and adding this residue to soil, it should act on the mitigation process of the greenhouse effect, especially CO2. The objectives of this study were to ...

  12. Histoire d’un itinéraire épidémiologique entre le Burkina Faso et la Côte d’Ivoire : le cas des foyers de maladie du sommeil de Koudougou

    PubMed Central

    Kiendrébéogo, D.; Kambiré, R.; Jamonneau, V.; Lingué, K.; Solano, P.; Courtin, F.

    2012-01-01

    Dans la première moitié du XXème siècle, alors que la Haute-Volta (actuel Burkina Faso) subissait une terrible épidémie de maladie du sommeil, l’administration coloniale française a orchestré des déplacements massifs de populations de la Haute-Volta vers la Côte d’Ivoire, pour exploiter le territoire. Cela a conduit à la mise en place de villages de colonisation Mossi en zone forestière ivoirienne, comme ceux de Koudougou, issus de l’une des régions les plus peuplées de Haute-Volta, mais aussi l’une des plus touchées par la maladie du sommeil. Depuis 2000, au Burkina Faso, c’est dans le district sanitaire de Koudougou que sont dépistés passivement le plus grand nombre de trypanosomés en provenance de Côte d’Ivoire. Qui sont-ils ? Où habitent-ils au Burkina Faso ? D’où viennent-ils de Côte d’Ivoire ? Après avoir retracé l’histoire épidémiologique des villages de Koudougou au Burkina Faso et en Côte d’Ivoire, nous avons recherché les trypanosomés dépistés passivement depuis 2000 dans le district sanitaire de Koudougou au Burkina Faso. Au total, dix trypanosomés ont été enquêtés. Le processus de propagation de la maladie du sommeil dans l’espace ivoiro-burkinabé a été mis en évidence et des zones à risque de la maladie identifiées dans ce même espace. PMID:23193525

  13. O Imperio como Argumento: Um Contraponto entre Joaquim Nabuco e o Bispo D. Jose Mauricio da Rocha (The Empire as Argument: A Counterpoint between Joaquim Nabuco and the Bishop Dom Jose Mauricio da Rocha).

    ERIC Educational Resources Information Center

    Marson, Izabel Andrade

    1998-01-01

    Dialogs with the previous article establishing a comparative analysis between the political acceptance present in the reactionary speech of Dom Jose Mauricio da Rocha and in the monarchist words of Joaquim Nabuco. (PA)

  14. Conséquences de l'interaction entre préférences pour l'habitat et quantité de ressources trophiques sur les communautés d'insectes coprophages (Coleoptera: Scarabaeoidea)

    NASA Astrophysics Data System (ADS)

    Kadiri, Nassera; Lobo, Jorge M.; Lumaret, Jean-Pierre

    Between the years 1988 and 1995, five dung beetle communities were studied in combined conditions of habitat and trophic resources. Investigations were conducted on La Viale experimental farm, in the Causse Méjean, southern France. At each site, dung beetle traps of standard design were set up simultaneously. In most situations, the vegetation cover acted like a filter that allowed the penetration of several ubiquitous but fundamentally open-habitat dung beetle species into forest, at the same time drastically limiting their numbers. Open and close sites differed significantly, open and grazed sites showing the highest richness, abundance and biomass in beetles. Both in open and close sites, a significant increase in trophic resources led to an increase of the diversity and evenness. However in open-habitat, when resources were too abundant, few species were favoured and the diversity and evenness decreased. In forest-habitat, a continuous grazing during several years (increase in resources) modified the dung beetle community, with a high increase in the numbers and biomass of beetles but a smaller increase in richness. Numbers in forest habitat readjusted to the level observed in open habitat with equivalent trophic resources. Similarly to what was observed in open pastures, the forest communities were able to adjust their numbers to the level of available trophic resources. Resources were a more active variable than the structure of habitat on the dung beetle communities. Important resources go against the filter effect which allows the penetration under cover of open-habitat species. Changes were slow (several years), and forest communities remained weak. The poverty of forest habitats is discussed: This scarcity in species is probably due to long time human activities in Europe which drastically reduced forest habitats and developped grazing, favouring generalist and heliophilous open-habitat dung beetle species. Actual grassland communities in Europe are richer than their homologous communities in North America. Conversely, in North America where human activities are recent, the true forest dung beetle communities are still diverse and richer than grassland communities.

  15. Online Peer Feedback between Colombian and New Zealand FL Beginners: A Comparison and Lessons Learned (Retroalimentación virtual de pares entre aprendices principiantes de lengua de Colombia y Nueva Zelanda: una comparación y lecciones aprendidas)

    ERIC Educational Resources Information Center

    Tolosa, Constanza; Ordóñez, Claudia Lucía; Alfonso, Tania

    2015-01-01

    We report on an exploratory study comparing the performance as online tutors of two groups of beginner eleven-year-old students of English in Colombia and Spanish in New Zealand. The native speaker students of the foreign language the others were learning corrected paragraphs written by their peers. The feedback provided by each group of tutors…

  16. Como ayudar a su hijo a tener exito en la escuela, con actividades para ninos entre las edades de 5 a 11 anos (Helping Your Child Succeed in School, with Activities for Children Ages 5 through 11).

    ERIC Educational Resources Information Center

    Paulu, Nancy

    At the heart of the No Child Left Behind Act of 2001 is a promise to raise standards for all children and to help all children meet those standards. This Spanish-language booklet provides information that parents can use to help their child succeed in school. Following an introduction, the second section of the booklet, "The Basics," offers…

  17. Vinculacion Entre La Educacion Y El Mundo Del Trabajo: Informe Final. (Coloquio Regional Caracas, Venezuela, Septiembre 2-6, 1985) = The Linkage Between Education and Employment: Final Report of the Regional Colloquium (Caracas, Venezuela, September 2-6, 1985).

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Santiago (Chile). Regional Office for Education in Latin America and the Caribbean.

    At this regional colloquium 13 papers were presented concerning the relationship between education and employment. Themes addressed were: (1) the transformation of the workplace by technology and science; (2) the future of the disadvantaged population as a consequence of the technological revolution; and (3) the resulting changes in the education…

  18. Le « Harcèlement Entre Pairs » À L'école élémentaire Tchèque: Une Question D'interprétation

    NASA Astrophysics Data System (ADS)

    Kohout-Diaz, Magdalena

    2008-07-01

    "PEER BULLYING" IN CZECH PRIMARY SCHOOLS: A QUESTION OF INTERPRETATION—This article questions adults' reports of an alleged increase in peer bullying at Czech primary schools. A survey on the school climate revealed that the pupils see it as a generally positive one and consider their relationships to be good. However, compared to France, their behaviour towards the adults is aggressive and rude. This apparent contradiction is linked to a conflict between the educational norms carried over from the old regime (behavioural control and conformism) and the new socio-economic paradigms (critical thinking and free enterprise). Public opinion, the media and a number of scientifically-questionable studies have drawn attention to the phenomenon of peer bullying ( šikana), and applied an imported concept to describe it ( school bullying). This makes it possible to avoid questioning the part played by the adults, the school and the researchers; justify segregating pupils from socially, culturally or economically disadvantaged backgrounds (Roma); and facilitate the country's socio-economic inclusion in the European Union by highlighting educational problems about whose nature there is general agreement.

  19. The Differences between Spoken and Written Grammar in English, in Comparison with Vietnamese (Las Diferencias entre la Gramática Oral y Escrita del Idioma Inglés en Comparación con el Idioma Vietnamita)

    ERIC Educational Resources Information Center

    Thanh, Nguyen Cao

    2015-01-01

    The fundamental point of this paper is to describe and evaluate some differences between spoken and written grammar in English, and compare some of the points with Vietnamese. This paper illustrates that spoken grammar is less rigid than written grammar. Moreover, it highlights the distinction between speaking and writing in terms of subordination…

  20. Highlighting the Impacts of North-South Research Collaboration among Canadian and Southern Higher Education Partners (Principaux impacts des collaborations de recherche Nord-Sud entre les partenaires des etablissements d'enseignement superieur du Canada et du Sud)

    ERIC Educational Resources Information Center

    Association of Universities and Colleges of Canada, 2006

    2006-01-01

    The Association of Universities and Colleges of Canada (AUCC) felt it was timely to create an academic forum in which university researchers have the opportunity to engage with their peers and relevant stakeholders and document the impacts of their North-South research collaboration in a peer-reviewed publication. The Association achieved this by…

  1. Parámetros astrofísicos fundamentales de 6 cúmulos de la Nube Mayor de Magallanes en el rango de transición entre 200 y 700 millones de años

    NASA Astrophysics Data System (ADS)

    Piatti, A. E.; Bica, E.; Geisler, D.; Clariá, J. J.

    Complementing our recent Washington photometric studies on intermediate age and young Large Magellanic Cloud (LMC) clusters, we present in this work new results for 6 previously unstudied star clusters in the transition range 200-700 Myr. We study NGC 1836, NGC 1860 and NGC 1865, which are projected on the LMC bar; SL 444, also located in the central disc but outside the bar, and LW 224 and SL 548, both located in the outer disc. We derive ages and metallicities from extracted T1 versus C-T1 colour-magnitude diagrams (CMDs), using theoretical isochrones recently computed for the Washington system. For the metallicity determinations, these CMDs are particularly sensitive. We also estimate ages and metallicities of the surrounding fields of NGC 1860 and NGC 1865 by employing the δT1 index and theoretical isochrones.

  2. Pushing Too Little, Praising Too Much? Intercultural Misunderstandings between a Chinese Doctoral Student and a Dutch Supervisor (¿Empujando muy poco, felicitando demasiado? Malentendidos interculturales entre un estudiante de doctorado Chino y un supervisor Holandés)

    ERIC Educational Resources Information Center

    Hu, Yanjuan; van Veen, Klaas; Corda, Alessandra

    2016-01-01

    To understand the challenges and their causes in interactions between Western supervisors and international doctoral students, we conducted a self-study of our experiences as a Chinese international student and her Dutch supervisor during her doctoral research project. We found the supervisor and the student to differ in their expectations of the…

  3. Peer Interaction: A Social Perspective towards the Development of Foreign Language Learning (Interacción entre pares: una perspectiva social hacia el desarrollo del aprendizaje en una lengua extranjera)

    ERIC Educational Resources Information Center

    Gómez Lobatón, July Carolina

    2011-01-01

    This pedagogical innovation aims at discovering new ways of interaction that go beyond the unidirectional relationship that is presented in the classrooms most of the times. The innovation considers peers to be active agents in the construction of knowledge and proposes new ways to arrange groups in the classroom so that the arrangement can…

  4. Positive Prevention: Successful Approaches To Preventing Youthful Drug and Alcohol Use [and] La Prevencion Positiva: Metodos que han tenido exito en la prevencion del uso de drogas y alcohol entre la juventud.

    ERIC Educational Resources Information Center

    American Association of School Administrators, Arlington, VA.

    The United States has the highest rate of youthful drug abuse of any industrialized country in the world. There is a growing awareness that drug and alcohol use are closely connected to other problems such as teenage suicide, adolescent pregnancy, traffic fatalities, juvenile delinquency, poor school performance, runaways, and dropouts. Youthful…

  5. Eco-hydrology: Groundwater flow and site factors in plant ecology

    NASA Astrophysics Data System (ADS)

    Klijn, Frans; Witte, Jan-Philip M.

    proporciona unas condiciones de vida adecuadas que permiten el crecimiento de una especie o una comunidad botánica. En un material inicialmente homogéneo, el flujo subterráneo gravífico influencia las condiciones del emplazamiento variando la distribución espacial de los nutrientes y de otros agentes químicos relevantes. En especial, el flujo ascendente puede producir y mantener una serie de condiciones que son esenciales para algunas especies y comunidades de plantas relativamente raras. La especial atención hacia este fenómeno ha dado lugar a una cooperación entre ecologistas e hidrogeólogos y a la aparición de una nueva disciplina - eco-hidrología -, en la frontera de los dos campos científicos. En Holanda, se ha usado una clasificación sencilla de tipos de agua para crear una base de datos, a nivel nacional, de lugares donde la presencia de flujos ascendentes pueda ser de interés ecológico. El análisis de correspondencias entre esta base de datos y los tipos de plantas existentes muestra que en los suelos arenosos pobres del Pleistoceno los flujos ascendentes explican la presencia de algunas especies y comunidades de plantas. Por el contrario, en las llanuras fluviales y pólders, con suelos más arcillosos, la influencia de estos flujos es despreciable frente a la relativa a las propias características de los suelos. Se concluye que las especies botánicas se pueden usar como indicadores de la presencia de flujo ascendente sólo en campañas preliminares, pero que el método presenta grandes limitaciones para su extensión a casos generales.

  6. Hydraulic properties and scale effects investigation in regional rock aquifers, south-western Quebec, Canada

    NASA Astrophysics Data System (ADS)

    Nastev, M.; Savard, M. M.; Lapcevic, P.; Lefebvre, R.; Martel, R.

    subterránea sucede en los primeros metros de la secuencia rocosa. A escala regional se puede aplicar la aproximación equivalente de medios porosos. Las medidas de la conductividad hidrálica fueron comparadas con la escala de las pruebas del acuífero, expresadas con el volumen investigado del acuífero. Se desarrolló un proceso de interpolación simple para la conductividad hidráulica de campo, con base en la distancia entre las medidas de campo y los volúmenes probados del acuífero. La distribución regional de la conductividad hidráulica, para las unidades acuíferas fracturadas mayores, indica que la dolomita es más permeable mientras que la arenisca y las rocas cristalinas son las unidades menos permeables. L'article présente les propriétés hydrauliques d'un aquifère régional rocheux qui ont été mesurées dans le cadre d'un projet concernant l'estimation de la ressource en eau de la plaine de St. Lawrence située dans la partie sud-ouest de Quebec. Affin de comprendre le comportement de l'aquifère tant à l'échelle de fracture qu'à l'échelle régionale on a mené des investigations hydrauliques en utilisant des essais differents. À l'échelle locale l'écoulement est déterminé en principal par le système des fractures. Les résultats des essais d'injection au niveau constant ont montré une tendence de décroissance de la conductivité hydraulique avec la profondeur ce qui indique que l'écoulement ait lieu en principal dans les premiers mètres de la structure rocheuse. À l'échelle règionale on peut appliquer l'approche de milieux poreux equivalent. Les mesures de conductivité hydraulique ont été corrélées avec l'échelle des essais de pompage exprimée en termes de volume investigué de l'aquifère. On a mis au point une méthode simple d'interpolation pour le champ de la conductivité hydraulique basée sur la distance entre les essais in situ et les volume investigués de l'aquifère. La distribution règionale de la conductivit

  7. Estudio de la influencia de la refrigeracion con aire de forma natural e inducida en el comportamiento de instalaciones fotovoltaicas

    NASA Astrophysics Data System (ADS)

    Mazon Hernandez, Rocio

    panels are analysed to compare and select the best configuration. The presented research provides a deep knowledge of how they work as well as information and results for an improvement in future designs of building integrated photovoltaic systems. Este estudio se centra en analizar la influencia negativa de la temperatura en la produccion electrica de paneles fotovoltaicos al estar emplazados sobre cubierta de acero, como sucede en naves industriales y sobre un invernadero. Se estudian diferentes configuraciones que permitan refrigerar los paneles, reduciendo su temperatura y mejorar su rendimiento. Para abordar este problema, se han construido dos instalaciones experimentales, fieles a plantas solares en funcionamiento. Una instalacion engloba dos paneles fotovoltaicos sobre estructura fija al suelo. Uno de los paneles esta integrado sobre una superficie paralela y metalica. Entre ambas superficies existe un espacio que posibilita circular aire, permitiendo refrigerar el panel por conveccion natural, o conveccion forzada impulsando el aire con un ventilador. El otro panel, libre por su cara posterior y se ha considerado de referencia. Se ha estudiado el comportamiento del panel integrado sobre cubierta para diferentes secciones de aire y velocidades inducidas, comparandolo con el panel de referencia. Se ha desarrollado un modelo experimental que nos permite determinar la temperatura del panel en funcion de las variables que influyen en su refrigeracion. Adicionalmente, se han analizado los datos de una planta solar en funcionamiento, con paneles de igual caracteristicas, obteniendo correlaciones entre la temperatura del panel y las variables electricas y comparandolos con las obtenidas en la instalacion experimental. La segunda instalacion experimental reproduce parte de una instalacion solar sobre un invernadero, formada por cuatro paneles fotovoltaicos colocados sobre el plastico del invernadero, existiendo un canal divergente entre ambas superficies. Se estudia la

  8. Phytoreovirus-like sequences isolated from salivary glands of the glassy-winged sharpshooter Homolodisca vitripennis (Hemiptera: Cicadellidae)

    SciTech Connect

    Katsar, C.S.; Hunter, W.B. . E-mail: Whunter@ushrl.ars.usda.gov; Sinisterra, X.H.

    2007-03-15

    GWSS occurs, such as in southern California, will provide a better understanding of the potential role of the GWSS as a disease vector in the spread of phytoreoviruses and other plant pathogens. The sequences have been deposited in NCBI database under the accession numbers (EF058280) for GWSS-V1, WHSg013C11 and (EF058281) for GWSS-V2, WHSg024H02. (author) [Spanish] Dos fragmentos de 610 y 839 pares de bases fueron aislados apartir de una genoteca de expresion derivada de las glandulas salivales del cucarron de las alas cristalinas (GWSS), Homalodisca vitripennis, Germar 1821 (syn. H. coagulata) el cual es vector de la enfermedad de Pierce de las uvas. Los resultados de alineamiento utilizando BLASTX, BLASTP y el analisis filogenetico utilizando PAUP indicaron que los fragmentos de DNA estaban relacionado de manera mas cercana a viruses en la familia Reoviridae, genero Phytoreovirus, y especificamente a los virus del enanismo del arroz (RDV) y al virus del tumor de las grietas (WTV). El cucarron de las alas cristalinas es un saltahoja que se alimenta no solo del xilema sino tambien del floema y del mesofilo. Saltahojas del genero Agallian, son los principales vectores de WTV, el cual infecta el floema de plantas dicotiledoneas tumoraciones en las hojas y en las raices. WTV es transmitido por saltahojas y es el unico reovirus que es capaz de infectar tanto tejidos del xilema como del floema. El comportamiento alimentario del GWSS y su amplio rango de hospederos que incluye pastos y plantas herbaceas y lenosas podria proveer la interaccion entre estos dos organismos facilitando la adquisicion y tranmision de fitoreovirus por el GWSS. Un adecuado monitoreo de el incremento en la expansion de reoviruses en cultivos de gramineas asociados al los vinedos en donde GWSS ocurre en regiones tales como el sur de California, y en general el sur de los Estados Unidos, podria proveer un mejor entendimiento del papel del GWSS como vector de fitoreovirus y otros patogenos de plantas

  9. Geostatistical mapping of leakance in a regional aquitard, Oak Ridges Moraine area, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Desbarats, A. J.; Hinton, M. J.; Logan, C. E.; Sharpe, D. R.

    2001-01-01

    'imperméable, dans le but d'évaluer l'importance relative des processus d'alimentation des aquifères inférieurs. À partir d'une vaste base de données constituée par les mesures faites dans les puits et contenant des informations à la fois certaines et incertaines, la méthode de simulation par indicateur séquentiel est utilisée pour créer des cartes d'épaisseur de l'imperméable et de probabilité d'existence des fenêtres. Ces cartes peuvent être utilisées pour mettre en évidence les aquifères de chenaux et pour identifier les zones potentielles de recharge des aquifères inférieurs. Les conductivités hydrauliques sont modélisées à partir de données clairsemées en supposant que leur gamme de corrélation est beaucoup plus faible que le pas de la grille. La drainance à l'échelle des blocs est obtenue par accroissement du niveau d'échelle des valeurs nodales basé sur les champs de conductivité simulée et des épaisseurs. À partir de l'hypothèse d'écoulement dans l'aquifère, l'accroissement d'échelle est réalisé en faisant une moyenne arithmétique spatiale. Des histogrammes et des cartes de drainance avec accroissement d'échelle montrent que les hétérogénéités associées aux fenêtres dans l'imperméable constituent l'effet le plus important dans l'organisation des écoulements souterrains régionaux. Resumen. El Till de Newmarket forma un acuitardo de extensión regional que separa dos sistemas acuíferos principales en la zona de Greater Toronto (Canadá). El till está horadado, y a veces completamente erosionado, por una red de canales rellenos de arena y grava. Estos constituyen acuíferos productivos y, localmente, conexiones de alta permeabilidad entre sistemas acuíferos. El goteo a través del till puede ser fundamental en ciertos lugares. Este estudio investiga la variabilidad espacial del goteo desde el acuitardo con el fin de establecer la importancia relativa de los procesos de recarga hacia los acuíferos inferiores. Se ha

  10. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    We present the results obtained in a research on the comprehension of basic astronomical concepts, in which 561 students from fifth grade middle school to third grade high school of a public school of the city of Foz do Iguaçu (Brazil) took part. A test with 20 multiple-choice questions was applied to indentify the most common conceptions expressed by the students. This test was elaborated based on the literature about misconceptions and covered the following topics: the day-night cycle; the time zones; the seasons of the year; the phases of the Moon; the movement of the Moon; the apparent movement of the Sun in the celestial sphere; the eclipses; the dimensions and distances in the Universe; the brightness of the stars and its observation from Earth. Though a small progress was verified in the proportion of scientifically acceptable answers when comparing the eighth grade of middle school to the fifth, and the third grade of high school to the first, there was an overall predominance of alternative conceptions regarding most of the explored subjects, which persisted up to the last year of secondary school. The comparison to data found in this research made in other socio-cultural contexts revealed, in many aspects, similar notions and difficulties revealed by the students. Se presentan los resultados de una investigación sobre la comprensión de conceptos astronómicos básicos, en la cual participaron 561 estudiantes que cursaban entre el quinto grado de la enseñanza primaria y el tercer año de la enseñanza secundaria de una escuela pública de la ciudad de Foz do Iguaçu (Brasil). Se utilizó un test de 20 preguntas de opción múltiple para identificar las concepciones más comunes expresadas por los estudiantes. Este instrumento de recolección de datos se desarrolló en base a la literatura sobre las concepciones alternativas y trató los siguientes temas: el ciclo día-noche, los husos horarios, las estaciones del año, las fases de la Luna, el

  11. The Understanding of Astronomy Concepts by Students from Basic Education of a Public School. (Spanish Title: El Entendimiento de Conceptos de Aastronmía Por Los Alumnos de Educación Básica en Una Escuela Pública.) O Entendimento de Conceitos de Astronomia Por Alunos da Educação Básica: O Caso de Uma Escola Pública Brasileira

    NASA Astrophysics Data System (ADS)

    Iria Machado, Daniel; dos Santos, Carlos

    2011-07-01

    We present the results obtained in a research on the comprehension of basic astronomical concepts, in which 561 students from fifth grade middle school to third grade high school of a public school of the city of Foz do Iguaçu (Brazil) took part. A test with 20 multiple-choice questions was applied to indentify the most common conceptions expressed by the students. This test was elaborated based on the literature about misconceptions and covered the following topics: the day-night cycle; the time zones; the seasons of the year; the phases of the Moon; the movement of the Moon; the apparent movement of the Sun in the celestial sphere; the eclipses; the dimensions and distances in the Universe; the brightness of the stars and its observation from Earth. Though a small progress was verified in the proportion of scientifically acceptable answers when comparing the eighth grade of middle school to the fifth, and the third grade of high school to the first, there was an overall predominance of alternative conceptions regarding most of the explored subjects, which persisted up to the last year of secondary school. The comparison to data found in this research made in other socio-cultural contexts revealed, in many aspects, similar notions and difficulties revealed by the students. Se presentan los resultados de una investigación sobre la comprensión de conceptos astronómicos básicos, en la cual participaron 561 estudiantes que cursaban entre el quinto grado de la enseñanza primaria y el tercer año de la enseñanza secundaria de una escuela pública de la ciudad de Foz do Iguaçu (Brasil). Se utilizó un test de 20 preguntas de opción múltiple para identificar las concepciones más comunes expresadas por los estudiantes. Este instrumento de recolección de datos se desarrolló en base a la literatura sobre las concepciones alternativas y trató los siguientes temas: el ciclo día-noche, los husos horarios, las estaciones del año, las fases de la Luna, el

  12. The quiescent center and the stem cell niche in the adventitious roots of Arabidopsis thaliana

    PubMed Central

    Della Rovere, Federica; Fattorini, Laura; Ronzan, Marilena; Falasca, Giuseppina; Altamura, Maria Maddalena

    2016-01-01

    ABSTRACT Adventitious rooting is essential for the survival of numerous species from vascular cryptogams to monocots, and is required for successful micropropagation. The tissues involved in AR initiation may differ in planta and in in vitro systems. For example, in Arabidopsis thaliana, ARs originate from the hypocotyl pericycle in planta and the stem endodermis in in vitro cultured thin cell layers. The formation of adventitious roots (ARs) depends on numerous factors, among which the hormones, auxin, in particular. In both primary and lateral roots, growth depends on a functional stem cell niche in the apex, maintained by an active quiescent center (QC), and involving the expression of genes controlled by auxin and cytokinin. This review summarizes current knowledge about auxin and cytokinin control on genes involved in the definition and maintenance of QC, and stem cell niche, in the apex of Arabidopsis ARs in planta and in longitudinal thin cell layers. PMID:27089118

  13. The quiescent center and the stem cell niche in the adventitious roots of Arabidopsis thaliana.

    PubMed

    Rovere, Federica Della; Fattorini, Laura; Ronzan, Marilena; Falasca, Giuseppina; Altamura, Maria Maddalena

    2016-05-01

    Adventitious rooting is essential for the survival of numerous species from vascular cryptogams to monocots, and is required for successful micropropagation. The tissues involved in AR initiation may differ in planta and in in vitro systems. For example, in Arabidopsis thaliana, ARs originate from the hypocotyl pericycle in planta and the stem endodermis in in vitro cultured thin cell layers. The formation of adventitious roots (ARs) depends on numerous factors, among which the hormones, auxin, in particular. In both primary and lateral roots, growth depends on a functional stem cell niche in the apex, maintained by an active quiescent center (QC), and involving the expression of genes controlled by auxin and cytokinin. This review summarizes current knowledge about auxin and cytokinin control on genes involved in the definition and maintenance of QC, and stem cell niche, in the apex of Arabidopsis ARs in planta and in longitudinal thin cell layers. PMID:27089118

  14. Spatial patterns of carbon, biodiversity, deforestation threat, and REDD+ projects in Indonesia

    PubMed Central

    Murray, Josil P; Grenyer, Richard; Wunder, Sven; Raes, Niels; Jones, Julia PG

    2015-01-01

    del Carbono, la Biodiversidad, la Amenaza de Deforestación y los Proyectos REDD+ en Indonesia Resumen Actualmente hay preocupación por que las Emisiones Reducidas de la Deforestación y Degradación del Bosque (REDD+, en inglés) puedan fallar en la entrega de co–beneficios potenciales de la biodiversidad si se enfocan en áreas de alto carbono. Exploramos los traslapes espaciales entre los stocks de carbono, la biodiversidad, las amenazas proyectadas de deforestación y la ubicación de proyectos REDD+ en Indonesia, un país tropical a la vanguardia del desarrollo REDD+. Para la biodiversidad, reunimos datos sobre la distribución de vertebrados terrestres (hábitats de anfibios, mamíferos, aves y reptiles) y plantas (modelos de distribución de especies para ocho familia). Después investigamos la congruencia entre las diferentes medidas de la riqueza de la biodiversidad y los stocks de carbono en la escala nacional y sub–nacional. Finalmente mapeamos proyectos REDD+ activos e investigamos la densidad de carbono y la riqueza potencial de la biodiversidad y modelamos presiones de deforestación dentro de estos bosques en relación con áreas protegidas y no protegidas. Hubo poco traslape interno entre los diferentes hotspots (el 10% más rico de las celdas) de riqueza de especies. Tampoco hubo congruencia espacial consecuente entre los stocks de carbono y las medidas de la biodiversidad: una correlación negativa débil en la escala nacional enmascaró las relaciones altamente variables y no-lineales isla por isla. Los proyectos REDD+ actuales estuvieron ubicados preferencialmente en áreas con una riqueza total de especies y con una riqueza de especies amenazadas más altas pero con densidades de carbono más bajas que en las áreas protegidas y los bosques sin protección. Aunque un cuarto del área total de estos proyectos REDD+ está bajo una presión de deforestación relativamente alta, la mayoría del área REDD+ no lo está. Por lo menos en Indonesia

  15. Crystallization of DIR1, a LTP2-like resistance signalling protein from Arabidopsis thaliana

    SciTech Connect

    Lascombe, Marie-Bernard; Buhot, Nathalie; Bakan, Bénédicte; Marion, Didier; Blein, Jean Pierre; Lamb, Chris J.; Prangé, Thierry

    2006-07-01

    DIR1, a putative LTP2 protein from Arabidopsis thaliana implicated in systemic acquired resistance in planta, has been crystallized in space group P2{sub 1}2{sub 1}2{sub 1} with one molecule per asymmetric unit. DIR1, a putative LTP2 protein from Arabidopsis thaliana implicated in systemic acquired resistance in planta, has been crystallized in space group P2{sub 1}2{sub 1}2{sub 1} with one molecule per asymmetric unit. The crystals diffract to a resolution of 1.6 Å.

  16. La langue parlee le plus souvent entre les parents et les enfants: un facteur crucial dans l'acquisition linguistique de l'enfant dans un milieu bilingue (The Language Most Often Spoken between Parents and Children: A Crucial Factor in Child Language Acquisition in a Bilingual Environment). Working Papers on Bilingualism, No. 7.

    ERIC Educational Resources Information Center

    Hebrard, Pierre; Mougeon, Raymond

    The data for the study were gathered in the course of a larger sociolinguistic survey carried out among francophones from Welland and Sudbury, Ontario. Among other things, the acquisition of spoken English by bilingual francophone students from these cities was studied in depth, using error analysis. The present study attempts to show that in a…

  17. Efectos Especiales de Anclaje (Estudio sobre Regresiones de Juicios Condicionales). Parte 1: Distincion entre Efectos Aditivos y Efectos Multiplicativos en el Fenomeno de Anclaje (Special Effects of Anchoring (Study on Regression of Conditional Judgements) Part 1: Distinction Between Additive Effects and Multiplicative Effects in the Phenomenon of Anchoring). Publication No. 17.

    ERIC Educational Resources Information Center

    Lopez Alonso, A. O.

    A linear relationship was found between judgements given by 160 subjects to 7 objects presented as single stimuli (alpha judgements) and judgements given to the same objects presented with a condition (gamma judgements). This relationship holds for alpha judgements and the gamma judgements that belong to a family of constant stimulus and varying…

  18. Global Professional Identity in Deterretorialized Spaces: A Case Study of a Critical Dialogue between Expert and Novice Nonnative English Speaker Teachers (Identidad profesional global en espacios desterritorializados: un estudio de caso de los diálogos críticos entre profesores de inglés no nativos)

    ERIC Educational Resources Information Center

    Guerrero Nieto, Carmen Helena; Meadows, Bryan

    2015-01-01

    This study analyzes the online, peer-peer dialogue between two groups of nonnative English-speaking teachers who are attending graduate programs in Colombia and the United States. Framed by the theoretical concepts of critical pedagogy and global professional identity, a qualitative analysis of the data shows that their expert vs. novice roles…

  19. Construyendo un Puente entre la Educacion del Dotado y el Mejoramiento Escolar Integral. Resumen. La Serie de Decision Basada en la Investigacion (Building a Bridge between Gifted Education and Total School Improvement. Summary. Talent Development Research-Based Decision Making Series).

    ERIC Educational Resources Information Center

    Renzulli, Joseph S.

    This monograph addresses the role of gifted education in total school improvement by describing three service delivery components (the Total Talent Portfolio, Curriculum Modification Techniques, and Enrichment Learning and Teaching) and several organizational components of the Schoolwide Enrichment Model (SEM). The report describes how the SEM can…

  20. Tensions entre rationalité technique et intérêts politiques : l’exemple de la mise en œuvre de la Loi sur les agences de développement de réseaux locaux de services de santé et de services sociaux au Québec

    PubMed Central

    Contandriopoulos, D.; Hudon, Raymond; Martin, Elisabeth; Thompson, Daniel

    2013-01-01

    Sommaire L’objet de cet article est constitué par les processus décisionnels entourant la mise en œuvre de la Loi sur les agences de développement de réseaux locaux de services de santé et de services sociaux (Loi 25). Nous entendons mettre en lumière les stratégies des groupes ou institutions de diverses natures qui ont fait valoir leurs préférences et ont tenté, avec un succès inégal, d’influencer les décisions relatives à cette réforme majeure de la structure du système de santé québécois. Au plan théorique, nous nous appuyons principalement sur les modèles d’analyse du lobbying qui, depuis les travaux fondateurs de Milbrath (1960, 1963), présentent cette pratique comme un processus fondamental d’échange d’information. Selon les données colligées dans les retranscriptions d’entrevues, les stratégies observées correspondent effectivement aux caractéristiques constitutives du lobbying et, dans quelques situations, à celles du patronage. La combinaison de ces divers éléments révèle que la mise en œuvre de la Loi 25 s’avère être avant tout un processus proprement politique. Ainsi, furent relégués au second plan les arguments techniques qui composaient initialement les objectifs de la Loi. PMID:23509412

  1. El juego entre el nacimiento y los 7 anos: Un manual para ludotecarias. Investigacion-accion sobre la Familia y la Primera Infancia. UNESCO Sector de Educacion Monografia (Play between Birth and 7 Years: A Manual for Preschool Teachers. Action Research in Family and Early Childhood. UNESCO Education Sector Monograph).

    ERIC Educational Resources Information Center

    Grellet, Carolina

    The purpose of this Spanish-language manual is to help preschool teachers better understand theoretical concepts related to children's play. Following a preface that discusses UNESCO's activities related to early childhood education, the two main sections of the manual discuss children's play between 0-2 years and 2-7 years. Each section includes…

  2. Mitigation of Disagreement in Peer Review among L2 Learners and Native Speakers in a College Writing Class (Mitigación del Impacto de las Opiniones de Desacuerdo en el Proceso de Revisión por Pares entre Estudiantes de una Segunda Lengua y Hablantes Nativos en una Clase de Escritura a Nivel Universitario)

    ERIC Educational Resources Information Center

    Christoffersen, Katherine O'Donnell

    2015-01-01

    Peer review is now a commonplace practice in process-oriented writing instruction. A crucial aspect of peer review is assessing another classmate's work, which encompasses the act of disagreement. Given its prevalence in the classroom, it is necessary to analyze how L2 learners mitigate disagreement in the context of peer review with other L2…

  3. [The EMECAM protocol: an analysis of the short-term effect of air pollution on mortality. Estudio Multicéntrico Español sobre la Relación entre la Contaminación Atmosférica u la Mortalidad].

    PubMed

    Pérez-Hoyos, S; Sáez Zafra, M; Barceló, M A; Cambra, C; Figueiras Guzmán, A; Ordóñez, J M; Guillén Grima, F; Ocaña, R; Bellido, J; Cirera Suárez, L; López, A A; Rodríguez, V; Alcalá Nalvaiz, T; Ballester Díez, F

    1999-01-01

    The aim of this study is to Mortality show the protocol of analysis which was set out as part of the EMECAM Project, illustrating the application thereof to the effect of pollution has on the mortality in the city of Valencia. The response variables considered will be the daily deaths rate resulting from all causes, except external ones. The explicative variables are the daily series of different pollutants (black smoke, SO2, NO2, CO, O3). As possible confusion variables, weather factors, structural factors and weekly cases of flu are taken into account. A Poisson regression model is built up for each one of the four deaths series in two stages. In the first stage, a baseline model is fitted using the possible confusion variables. In the second stage, the pollution variables or the time legs thereof are included, controlling the residual autocorrelation by including mortality time lags. The process of fitting the baseline model is as follows: 1) Include the significant sinusoidal terms up to the sixth order. 2) Include the significant temperature or temperature squared terms with the time lags thereof up to the 7th order. 3) Repeat this process with the relative humidity. 4) Add in the significant terms of calendar years, daily tendency and tendency squared. 5) The days of the week as dummy variables are always included in the model. 6) Include the holidays and the significant time lags of up to two weeks of flu. Following the reassessment of the model, each one of the pollutants and the time lags thereof up to the fifth order are proven out. The impact is analyzed by six-month periods, including interaction terms. PMID:10410600

  4. En sus marcas--Listos--A leer! Para los cuidadores de ninos pequenos: Actividades de lenguaje para la primera infancia y ninez entre el nacimiento y los 5 anos. El reto: A leer, America! (Ready--Set--Read! For Caregivers: Early Childhood Language Activities for Children from Birth through Age Five. America Reads Challenge).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This Ready--Set--Read Kit includes an activity guide for caregivers, a 1997-98 early childhood activity calendar, and an early childhood growth chart. The activity guide presents activities and ideas that caregivers (family child care providers and the teachers, staff, and volunteers in child development programs) can use to help young children…

  5. En sus marcas--Listos--A leer! Para las familias: Actividades de lenguaje para la primera infancia y ninez entre el nacimiento y los 5 anos. El reto: A leer, America! (Ready--Set--Read! For Families: Early Childhood Language Activities for Children from Birth through Age Five. America Reads Challenge).

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC.

    This Ready--Set--Read Kit includes an activity guide for families, a 1997-98 early childhood activity calendar, and an early childhood growth wallchart. The activity guide presents activities and ideas that families (adults who have nurturing relationships with a child--a mother, father, grandparent, other relative, or close friend) can use to…

  6. Human Relations Activities for the Single Parent To Develop More Effective Parent/Child Relations. Bilingual Guide = Actividades sobre relaciones humanas para ayudar al padre-soltero o madre-soltera a desarrollar una relacion efectiva entre padre e hijo Guia bilingue.

    ERIC Educational Resources Information Center

    Peterson, Susan

    Written in English and Spanish, this bilingual guide offers 10 activities which single parents can use to improve their relationships with their children. Objectives of activities include: (1) developing children's responsibility for work tasks in the home; (2) improving sibling relationships; (3) discussing emergencies with children; (4)…

  7. Linking: Today's Libraries, Tomorrow's Technologies. Report of the Bibliographic and Communications Network Pilot Project. Canadian Network Papers Number 7 = Le Lien entre les Bibliotheques d'Aujourd'hui et les Technologies de Demain. Rapport du Projet Pilote du Reseau de Services Bibliographiques et de Communications. Documents sur les Reseaux Canadiens Numero 7.

    ERIC Educational Resources Information Center

    National Library of Canada, Ottawa (Ontario).

    A pilot project was conducted from May 1980 to November 1983 to test the application of iNet--a decentralized, packet-switched telecommunications network--to bibliographic data interchange in Canada. The principal components of the project were participation of the Bibliographic Common Interest Group (BCIP), a group of libraries with stand-alone,…

  8. Sur les inocérames de Tercis (Landes, France) : le meilleur outil corrélatif entre Europe et Amérique du Nord autour de la limite Campanien MaastrichtienInoceramids of the site of Tercis (Landes, France): the best correlative tool between Europe and North America across the Campanian Maastrichtian boundary

    NASA Astrophysics Data System (ADS)

    Odin, Gilles Serge; Walaszczyk, Ireneusz

    2003-01-01

    Four hundred inoceramids have been collected in the geological site at Tercis, where the Campanian-Maastrichtian boundary has been recently defined. At Tercis, a distinct drop of the adult size of inoceramids is observed between levels 111 and 117 and two turnovers of faunal composition were documented between levels 94 and 96 and between levels 111 and 117; the latter interval encompasses the stage boundary. The recognised inoceramid assemblages are very close to those known from North America, allowing better correlation than before between the two domains in the interval 77-70 Ma. The presence of these faunas perfectly located in the section leads to consider the Tercis section as the best known reference for this fossil group, the surprisingly good correlative potential of which has still to be considered in many areas.

  9. How To Talk to Your Doctor (and Get Your Doctor To Talk to You!). An Educational Workshop on Doctor Patient Communication = Como Hablarle a su Doctor (iY que su doctor le hable a usted!). Un seminario educativo sobre la comunicacion entre el doctor y el paciente.

    ERIC Educational Resources Information Center

    Baylor Coll. of Medicine, Houston, TX.

    This workshop, written in both English and Spanish, focuses on improving communication between physician and patient. In the workshop, the trainers will talk about "building bridges" between patient and doctor by understanding the doctor's role and his/her duty to the patient. According to the workshop, a person's doctor should communicate…

  10. Le complexe annulaire d'âge Oligocène de l'Achkal (hoggar Central, Sud Algérie) : témoin de la transition au Cénozoïque entre les magmatismes tholéitique et alcalin. Évidences par les isotopes du Sr, Nd et Pb

    NASA Astrophysics Data System (ADS)

    Maza, Mustapha; Briqueu, Louis; Dautria, Jean-Marie; Bosch, Delphine

    1998-08-01

    The Achkal Oligocene ring complex cross-cuts the Upper Eocene tholeiitic traps located on the top of the Hoggar swell. The plutonic rocks range from tholeiitic gabbros to alkali essexites, monzonites and syenites, whereas the volcanites are restricted to late peralkaline rhyolites. The affinity change linked to the large isotopic heterogeneities (from EM1 to HIMU) suggests that the parental magmas are issued from two distinct mantle sources, first lithospheric then deeper. The Achkal has recorded the magmatic evolution of the Hoggar hot spot, between Eocene and Miocene.

  11. Les Differences dans l'emploi de la construction possessive "N1"+"DE"+"N2" entre le XIX et le XX s. dans la prose litteraire francaise (Differences in the Use of the Possessive Construction "N1"+"de"+"N2" between 19th and 20th Century French Literature).

    ERIC Educational Resources Information Center

    Roglic, Vera

    1991-01-01

    Study looks at frequency of noun1 + de + noun2 possessive in French prose. Researchers used chi-square and Pearson test to analyze results of syntagmatic possessive construction in works by Hugo, Stendahl, Balzac, Zola, Gide, Malraux, St. Exupery, and Sartre. Findings indicate that syntagmatic genitive possessive is more commonly found in…

  12. Contamination par le nickel et d'autres métaux lors de la manipulation des pièces de monnaie comparaison entre francs français et eurosContamination by nickel and other metals resulting from the manipulation of coins comparison between French francs and euros

    NASA Astrophysics Data System (ADS)

    Fournier, P.-G.; Govers, T. R.; Fournier, J.; Abani, M.

    The introduction of the euro has revived the interest for potential nickel allergies. We show that the handling of a single used nickel coin releases an average of 0.45 μg of nickel, 0.26 μg of copper and 0.08 μg of zinc, whereas a euro coin composed of nickel alloys releases 0.25 μg of nickel, 1.3 μg of copper and 0.17 μg of zinc. These levels of contamination, favored by friction during handling, differ from those obtained on the basis of the EN 1811 test applicable to solubilisation in artificial sweat. The evaluation of allergy risks following the introduction of the euro may require the consideration of potential synergies between the metals mentioned above. To cite this article: P.-G. Fournier et al., C. R. Physique 3 (2002) 749-758.

  13. L'impact de l'enseignement de la biologie sur la construction de la distinction entre normal et pathologique chez les eleves du secondaire Marocain (The Impact of Teaching Biology on the Way Moroccan High School Students Construe the Difference between Normal and Pathological).

    ERIC Educational Resources Information Center

    Khzami, Salah-Eddine; Favre, Daniel

    2002-01-01

    Study of the distinction between the notions of the normal and the pathological among Moroccan high school students and their teachers of biology found that students confused the registers of the normal/abnormal with the healthy/pathological, a fact that is at odds with current teaching in biology. It also found a possible link to the values held…

  14. Apports des phyllosilicates dans la différenciation entre altération hypogène et altération supergène dans le basalte triasique du Moyen Atlas (Maroc)Contribution of phyllosilicates to distinguish between hypogene alteration and weathering in Triassic basalt from Middle Atlas (Morocco)

    NASA Astrophysics Data System (ADS)

    Dekayir, Abdelilah; Danot, Michel; Allali, Nabil

    2002-09-01

    Triassic basalt of the Middle Atlas has been subject to metamorphic transformation then weathering. Occurrence in both metabasalt and saprolite of ubiquitous clay minerals, such as smectite and mixed layers chlorite-smectite, makes it difficult to distinguish between the two alteration facies and explains the interest of complementary sources of information. In the Bhallil weathering profile, petrographical and mineralogical analyses of primary igneous minerals and their alteration products coupled with Fe oxidation state determination in clay fractions allow to identify three alteration facies: ( i) metamorphic basalt, where iron occurs mainly as the ferrous form; ( ii) the lower part of saprolite, where iron is partially oxidized to its ferric form; ( iii) the upper part of saprolite, where iron is completely oxidized. To cite this article: A. Dekayir et al., C. R. Geoscience 334 (2002) 877-884.

  15. Synergie entre la télédétection multispectrale et les données de terrain pour la conception d'un nouveau modèle géodynamique d'ouverture du bassin paléozoîque des Jebilet centrales (Maroc)

    NASA Astrophysics Data System (ADS)

    El Harti, Abderrazak; Bannari, Abderrazak; Bachaoui, El Mostafa; Aarab, El Mostafa; Girouard, Guillaume; El Ghmari, Abderrahmen

    2004-11-01

    The geodynamic model of the Palaeozoic basin opening of central Jebilet has been unknown before this study in spite of the abundance in the geological studies carried out in the studied sector using conventional methods. This is due to the scarcity of the key beds and synsedimentary structures. Using the synergy between the image data of the Landsat satellite TM sensor and the ground data, we have highlighted, herein, new structural data allowing the design of a new model of the Palaeozoic basin opening of central Jebilet. This opening could have been made according to dextral submeridian transverse faults with the individualization of subequatorial normal faults. To cite this article: A. El Harti et al., C. R. Geoscience 336 (2004).

  16. Nuevos fenómenos en erupciones cometarias

    NASA Astrophysics Data System (ADS)

    Silva, A.

    Se discuten aquí tres procesos físicos novedosos encontrados en la actividad de cometas: 1) El rol de una distribución de granos de hielo como fuente extendida de H2O en la coma, 2) El efecto de una discontinuidad en el plasma cometario, llamada Cometopausa, sobre la excitación del radical OH , y 3) La actividad por erupciones a grandes distancias heliocéntricas (r > 5 AU). Con respecto a 1) y 2), se presentan modelos que ajustan bien con las observaciones. En cuanto a 3), se presentan explicaciones posibles al fenómeno, y se trata el interesante caso de Chirón 2060, basándose en observaciones propias tomadas desde el CASLEO y datos anteriores.

  17. Formación estelar y AGNs en los entornos de quasars

    NASA Astrophysics Data System (ADS)

    Coldwell, G.; García Lambas, D.

    En este trabajo utilizamos las galaxias del catálogo 2dF (2dF public 100K data release) y muestras de quasars tomados del catálogo Verón-Cetty & Verón (2001) para estudiar la naturaleza de estas galaxias en los entornos de quasars con redshift en el rango 0.1< z < 0.2. Estudiamos la distribución de índices espectrales, η, de galaxias a distintas distancias proyectadas de quasars y con diferencias de velocidad radial Δ V <= 500 km s-1. Por comparación, realizamos el mismo análisis en una muestra de galaxias random del catálogo 2dF y en una muestra de cúmulos Abell con similar distribución de redshift que los quasars. Los resultados indican que existe una gran fracción de galaxias con fuertes líneas de emisión, eta > 3.5, en los entornos de quasars comparado con la fracción presente en las vecindades de galaxias típicas del 2dF. Analizamos las distribuciones de luminosidad para estas galaxias (eta > 3.5) encontrando un exceso de galaxias mas luminosas que M ˜ -19.5 en las vecindades de quasars, indicativo de la posible presencia de AGNs. Por otro lado, estimamos la tasa de formación estelar promedio para objetos a distintas distancias de quasars, galaxias y cúmulos de galaxias detectando una actividad de formacion estelar significativamente alta dentro de 1.5 Mpc h-1 de quasars con respecto a las galaxias del 2dF. Estos resultados proveen evidencia de un particular entorno de galaxias alrededor de Quasars.

  18. Comparison of Ergot Alkaloid Biosynthesis Gene Clusters in Claviceps Species Indicates Loss of Late Pathway Steps in Evolution of C. fusiformis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The grass parasites Claviceps purpurea and Claviceps fusiformis produce ergot alkaloids (EA) in planta and in submerged culture. Whereas EA synthesis (EAS) in C. purpurea proceeds via clavine intermediates to lysergic acid and the complex ergopeptines, C. fusiformis produces only agroclavine and ely...

  19. Characterizing resistance to infection by the root pathogen Armillaria mellea in tolerant and susceptible grapevine rootstocks.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapevine rootstocks that are resistant to the basidiomycete fungus Armillaria mellea have not been identified, mainly due to lack of a rapid and reliable inoculation technique. The aim of our research was to develop an in planta assay for inoculating grapevines and tracking root infection. We pro...

  20. Draft Genome Sequence of Burkholderia cenocepacia Strain 869T2, a Plant-Beneficial Endophytic Bacterium.

    PubMed

    Ho, Ying-Ning; Huang, Chieh-Chen

    2015-01-01

    An endophytic bacterium, Burkholderia cenocepacia 869T2, isolated from vetiver grass, has shown its abilities for both in planta biocontrol and plant growth promotion. Its draft genome sequence was determined to provide insights into those metabolic pathways involved in plant-beneficial activity. This is the first genome report for endophytic B. cenocepacia. PMID:26564046

  1. Aspergillus oryzae NRRL 35191 from coffee, a non-toxigenic endophyte with the ability to synthesize kojic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus oryzae was isolated as an endophyte from coffee leaves and found to produce kojic acid in culture. When inoculated in cacao seedlings (Theobroma cacao L.), A. oryzae grew endophytically and synthesize kojic acid in planta. Cacao seedlings inoculated with A. oryzae produced higher levels...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of azole-type P450 inhibitors and two metabolism-resistant ABA analogs on in vitro ABA 8'-hydroxylase activity, in planta ABA metabolism, endogenous ABA content, and tuber meristem dormancy duration were examined in potato (Solanum tuberosum L. cv. Russet Burbank). When functionally expr...

  3. The Irish Potato Famine Pathogen Phytophthora infestans Translocates the CRN8 Kinase into Host Plant Cells

    PubMed Central

    van Damme, Mireille; Bozkurt, Tolga O.; Cakir, Cahid; Schornack, Sebastian; Sklenar, Jan; Jones, Alexandra M. E.; Kamoun, Sophien

    2012-01-01

    Phytopathogenic oomycetes, such as Phytophthora infestans, secrete an arsenal of effector proteins that modulate plant innate immunity to enable infection. We describe CRN8, a host-translocated effector of P. infestans that has kinase activity in planta. CRN8 is a modular protein of the CRN effector family. The C-terminus of CRN8 localizes to the host nucleus and triggers cell death when the protein is expressed in planta. Cell death induction by CRN8 is dependent on its localization to the plant nucleus, which requires a functional nuclear localization signal (NLS). The C-terminal sequence of CRN8 has similarity to a serine/threonine RD kinase domain. We demonstrated that CRN8 is a functional RD kinase and that its auto-phosphorylation is dependent on an intact catalytic site. Co-immunoprecipitation experiments revealed that CRN8 forms a dimer or multimer. Heterologous expression of CRN8 in planta resulted in enhanced virulence by P. infestans. In contrast, in planta expression of the dominant-negative CRN8R469A;D470A resulted in reduced P. infestans infection, further implicating CRN8 in virulence. Overall, our results indicate that similar to animal parasites, plant pathogens also translocate biochemically active kinase effectors inside host cells. PMID:22927814

  4. There's No Such Thing as a One-Celled Plant or Animal.

    ERIC Educational Resources Information Center

    Kaveski, Sharon; And Others

    1983-01-01

    Considers the classification of organisms into five kingdoms based on evidence from molecular biology and microscopic techniques. Divides organisms into Protoctista, Monera, Fungi, Plantae, and Animalia, discussing characteristics of prokaryotes and eukaryotes as related to division of the kingdoms--prokaryotes in kingdom Monera and eukaryotes in…

  5. Probing Pseudomonas syringae host interactions using metatranscriptomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transcriptome analyses during the interaction of plants and pathogens can be used to provide insights into molecular mechanisms of plant resistance as well as the mechanisms used by bacteria to adapt to hosts and cause disease. We performed a dual in planta RNA-Seq experiment to profile RNA expressi...

  6. Cigarrillos de mentol | Smokefree Español

    Cancer.gov

    ¿Qué es el mentol? El mentol es una sustancia encontrada naturalmente en las plantas de menta, tales como la menta fresca y la hierbabuena. Deja una sensación refrescante y se usa frecuentemente para aliviar el dolor y la irritación leve, y para prevenir infecciones [1].

  7. The parA resolvase performs site-specific genomic excision in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have designed a site-specific excision detection system in Arabidopsis to study the in planta activity of the small serine recombinase ParA. Using a transient expression assay as well as stable transgenic plant lines, we show that the ParA recombinase is catalytically active and capable of perfo...

  8. The HDF1 histone deacetylase gene is important for conidiation, sexual reproduction, and pathogenesis in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head blight caused by Fusarium graminearum is an important disease of wheat and barley. Its genome contains chromosomal regions with higher genetic variation and enriched for genes expressed in planta, suggesting a role of chromatin modification in the regulation of infection-related genes. In a pre...

  9. Evolutionary relationships of Metazoa within the eukaryotes based on molecular data from Porifera.

    PubMed Central

    Schütze, J; Krasko, A; Custodio, M R; Efremova, S M; Müller, I M; Müller, W E

    1999-01-01

    Recent molecular data provide strong support for the view that all metazoan phyla, including Porifera, are of monophyletic origin. The relationship of Metazoa, including the Porifera, to Plantae, Fungi and unicellular eukaryotes has only rarely been studied by using cDNAs coding for proteins. Sequence data from rDNA suggested a relationship of Porifera to unicellular eukaryotes (choanoflagellates). However, ultrastructural studies of choanocytes did not support these findings. In the present study, we compared amino acid sequences that are found in a variety of metazoans (including sponges) with those of Plantae, Fungi and unicellular eukaryotes, to obtain an answer to this question. We used the four sequences from 70 kDa heat-shock proteins, the serine-threonine kinase domain found in protein kinases, beta-tubulin and calmodulin. The latter two sequences were deduced from cDNAs, isolated from the sponge Geodia cydonium for the phylogenetic analyses presented. These revealed that the sponge molecules were grouped into the same branch as the Metazoa, which is statistically (significantly) separated from those branches that comprise the sequences from Fungi, Plantae and unicellular eukaryotes. From our molecular data it seems evident that the unicellular eukaryotes existed at an earlier stage of evolution, and the Plantae and especially the Fungi and the Metazoa only appeared later. PMID:10081159

  10. Burkholderia phymatum Strains Capable of Nodulating Phaseolus vulgaris Are Present in Moroccan Soils ▿

    PubMed Central

    Talbi, C.; Delgado, M. J.; Girard, L.; Ramírez-Trujillo, A.; Caballero-Mellado, J.; Bedmar, E. J.

    2010-01-01

    Phylogenetic analysis of 16S rRNA, nodC, and nifH genes of four bacterial strains isolated from root nodules of Phaseolus vulgaris grown in Morocco soils were identified as Burkholderia phymatum. All four strains formed N2-fixing nodules on P. vulgaris and Mimosa, Acacia, and Prosopis species and reduced acetylene to ethylene when cultured ex planta. PMID:20472732

  11. Molecular characterization of an endornavirus from Cucumis spp

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endornaviruses infect hosts in the kingdoms Plantae, Fungi and Chromista. They are efficiently transmitted vertically and generally do not induce visible symptoms. In this investigation high molecular weight dsRNA, representing the genome of an endornavirus, was isolated from an unknown melon (Cucum...

  12. SITE-SPECIFIC RECOMBINATION FOR PLANT GENETIC ENGINEERING: STRATEGY FOR AGRO-MEDIATED GENE STACKING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The precise rearrangement of DNA in planta can be achieved through site-specific recombination. For the past decade and a half, laboratory experiments have shown that site-specific recombination can delete genomic DNA, regulate gene expression, recombine chromosomes, and target new DNA into designat...

  13. Transformation of Bacillus mojavensis with GFP and its endophytic localization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current studies on the use of bacterial endophytes for disease control and mycotoxin reduction in maize require the in planta localization and interaction of the intended biocontrol agent. Bacillus mojavensis, an endophytic species that has a phenotypic similarity to B. subtilis, has the potential...

  14. Variation in the TonB-dependent Outer-Membrane Proteins in Plant-Associated Strains of Pseudomonas fluorescens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient acquisition is key to the ecological fitness of environmental bacteria such as Pseudomonas fluorescens and TonB-dependent outer-membrane proteins are important components of the cellular machinery for the uptake of substrates from the environment. Genomic sequences of ten strains of plant-a...

  15. Extracellular Genomic DNA Mediates Enhancement of Xylella fastidiosa Biofilm Formation in Vitro

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xylella fastidiosa (Xf) produces extracellular DNA in PD3 liquid medium. This extracellular DNA could enhance biofilm formation, a factor in successful establishment of Xf in planta. The relative amounts of extracellular DNA were positively correlated with planktonic growth and biofilm formation in ...

  16. Biosynthsis of Lignin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order to understand the effects of up- and down-regulating genes on the lignin biosynthetic pathway, the intracacies of the pathway should be known. Many of the genes are long-known, although the actual substrates of some have been clarified in planta. Others are surprisingly new. All of the majo...

  17. The dynamics of apoplast phenolics in tobacco leaves following inoculation with bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study demonstrates that the accumulation of apoplastic phenolics is stimulated in planta in response to bacterial inoculation. Past studies have shown that levels of extracellular phenolics are elicited in plant cell suspensions in response to bacteria, and that tomato plants infected with vir...

  18. Functional, structural and phylogenetic analysis of domains underlying the Al-sensitivity of the aluminium-activated malate/anion transporter, TaALMT1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    TaALMT1 (Triticum aestivum Aluminum Activated Malate Transporter) is the founding member of a novel gene family of anion transporters (ALMTs) that mediate the efflux of organic acids. A small subgroup of root-localized ALMTs, including TaALMT1, is physiologically associated with in planta aluminum (...

  19. Molecular Characterization of Citrus Tristeza Virus Isolates from Mild Strain Cross Protection Experiments in Peru

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven isolates of Citrus tristeza virus (CTV) collected from the Topara Nursery, Lima, Peru were established as in planta cultures in Madam Vinous sweet orange in the Exotic Citrus Pathogen Quarantine Greenhouse, Beltsville, MD. Two of the isolates were collected from non-cross protected plants; Pe...

  20. Draft Genome Sequence of Burkholderia cenocepacia Strain 869T2, a Plant-Beneficial Endophytic Bacterium

    PubMed Central

    Ho, Ying-Ning

    2015-01-01

    An endophytic bacterium, Burkholderia cenocepacia 869T2, isolated from vetiver grass, has shown its abilities for both in planta biocontrol and plant growth promotion. Its draft genome sequence was determined to provide insights into those metabolic pathways involved in plant-beneficial activity. This is the first genome report for endophytic B. cenocepacia. PMID:26564046

  1. Advances in flavanoid glycosyltransferase research: integrating recent findings with long-term citrus studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonoid glycosides are required for a number of crucial roles in planta and have the potential for development in a variety of agricultural, medicinal, and biotechnological applications. A number of recent advancements have been made in characterizing glycosyltransferases, the enzymes that are res...

  2. Herbarium of the University of Malaga (Spain): Vascular Plants Collection

    PubMed Central

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    la colección principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996–2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  3. Herbarium of the university of malaga (Spain): vascular plants collection.

    PubMed

    García-Sánchez, José; Cabezudo, Baltasar

    2013-01-01

    ón principal del herbario. La base de datos MGC-Cormof tiene como objetivo la digitalización y publicación de los datos asociados con los más de 76.000 ejemplares depositados en la colección, de los cuales el 97,2% de las muestras se encuentran identificadas a nivel de especie. Desde 2011, los Servicios Centrales de Investigación (SCAI) de la Universidad de Málaga son responsables de mantener el herbario y sus respectivas bases de datos. Esta colección está en continuo crecimiento, con una incorporación anual de unos 1.500 ejemplares. Casi el 96% de la colección está digitalizada, a través del programa Herbar v3.7.1 (F. Pando et al. 1996-2011) por lo que más de 73.000 especímenes son accesibles a través de la red de GBIF (http://data.gbif.org/datasets/resource/8105/). Actualmente, la colección MGC-Cormof está constituida por 247 familias y 8.110 taxones, distribuidos en angiospermas (93,97%), helechos y plantas afines (4,89%) y gimnospermas (1,14%). Las familias y géneros mejor representados en la colección son Compositae, Leguminosae, Gramineae, Labiatae, Caryophyllaceae, Teucrium, Silene, Asplenium, Linaria y Quercus. La mayoría de los especímenes provienen de la región del Mediterráneo Occidental, fundamentalmente del sur de España (Andalucía: 82% de las muestras) y del norte de Marruecos (2,17%). Aproximadamente, el 63% de las muestras se encuentran georreferenciadas. La identificación de los ejemplares de la colección ha sido realizada por personal del departamento de biología vegetal de la Universidad de Málaga y además un 40% de los ejemplares ha sido revisado por especialistas. La base de datos MGC-Cormof ha sido revisada mediante la herramienta DarwinTest v3.2 (Ortega-Maqueda and Pando 2008) antes de ser publicada en GBIF. Los datos incluidos en esta base de datos son importantes para trabajos de conservación, taxonomía, flora, cartografía, fenología, palinología, entre otros. PMID:24194668

  4. Auxin and cytokinin control formation of the quiescent centre in the adventitious root apex of arabidopsis

    PubMed Central

    Della Rovere, F.; Fattorini, L.; D'Angeli, S.; Veloccia, A.; Falasca, G.; Altamura, M. M.

    2013-01-01

    Background and Aims Adventitious roots (ARs) are part of the root system in numerous plants, and are required for successful micropropagation. In the Arabidopsis thaliana primary root (PR) and lateral roots (LRs), the quiescent centre (QC) in the stem cell niche of the meristem controls apical growth with the involvement of auxin and cytokinin. In arabidopsis, ARs emerge in planta from the hypocotyl pericycle, and from different tissues in in vitro cultured explants, e.g. from the stem endodermis in thin cell layer (TCL) explants. The aim of this study was to investigate the establishment and maintenance of the QC in arabidopsis ARs, in planta and in TCL explants, because information about this process is still lacking, and it has potential use for biotechnological applications. Methods Expression of PR/LR QC markers and auxin influx (LAX3)/efflux (PIN1) genes was investigated in the presence/absence of exogenous auxin and cytokinin. Auxin was monitored by the DR5::GUS system and cytokinin by immunolocalization. The expression of the auxin-biosynthetic YUCCA6 gene was also investigated by in situ hybridization in planta and in AR-forming TCLs from the indole acetic acid (IAA)-overproducing superroot2-1 mutant and its wild type. Key Results The accumulation of auxin and the expression of the QC marker WOX5 characterized the early derivatives of the AR founder cells, in planta and in in vitro cultured TCLs. By determination of PIN1 auxin efflux carrier and LAX3 auxin influx carrier activities, an auxin maximum was determined to occur at the AR tip, to which WOX5 expression was restricted, establishing the positioning of the QC. Cytokinin caused a restriction of LAX3 and PIN1 expression domains, and concomitantly the auxin biosynthesis YUCCA6 gene was expressed in the apex. Conclusions In ARs formed in planta and TCLs, the QC is established in a similar way, and auxin transport and biosynthesis are involved through cytokinin tuning. PMID:24061489

  5. Three-dimensional mathematical model to simulate groundwater flow in the lower Palar River basin, southern India

    NASA Astrophysics Data System (ADS)

    Senthilkumar, M.; Elango, L.

    principales en el río, además de numerosos pozos distribuidos por la zona. El modelo simula el flujo de las aguas subterráneas en una superficie de 392 km2 por medio de 70 filas, 40 columnas y 2 capas. El modelo ha sido empleado en condiciones transitorias, por medio de la aproximación en diferencias finitas de las ecuaciones diferenciales parciales en tres dimensiones del flujo en el acuífero durante el período 1991-2001. Se ha calibrado el modelo en condiciones permanentes y transitorias. El ajuste entre los niveles calculados y medidos es razonable. A partir de los resultados de la modelación, se ha obtenido que el sistema acuífero es estable con la tasa de bombeo utilizada, exceptuando unos pocos emplazamientos a lo largo de la costa, donde se ha dado lugar a fenómenos de intrusión marina en una distancia de 50-100 m. El modelo transitorio ha sido ejecutado hasta el año 2010 para predecir el flujo dinámico bajo diversos escenarios de sobreexplotación y de reducción de la recarga. Se produce una disminución en los niveles piezométricos de 0.6 a 0.8 m en la zona oriental, donde el sistema acuífero está sometido a una extracción adicional de 2 millones de galones por día en la estación principal de bombeo. Incluso con las extracciones actuales, los niveles piezométricos se sitúan bajo el nivel del mar durante las épocas secas. El modelo predice el comportamiento de este sistema acuífero bajo varias condiciones de presión hidrológica.

  6. Restriction des communications entre l'Atlantique et la Méditerranée au Messinien : apport de la téphrochronologie dans la plate-forme carbonatée et le bassin de Melilla Nador (Rif nord-oriental, Maroc)Restriction of the seawater exchanges between the Atlantic and the Mediterranean during the Messinian: contribution of the tephrochronology of the Melilla Nador area (north-eastern Rif, Morocco)

    NASA Astrophysics Data System (ADS)

    Münch, Philippe; Roger, Stephan; Cornée, Jean-Jacques; Saint Martin, Jean-Paul; Féraud, Gilbert; Moussa, Abdelkhalak Ben

    2001-05-01

    Thirty-eight volcanic layers have been found, from the littoral carbonate platform to the basin, interbedded within the Neogene deposits of the Melilla-Nador area. Ten of them, whose stratigraphic location and geographic extension have been established, were petrographically and mineralogically studied. They have been used as markers to establish an overall platform/basin correlation sketch. Together with these correlations and a synthesis of available ages, we show that the sedimentation areas, and thus the oceanic circulations, progressively restricted in this region between 6.5 and 5.77 Ma as a consequence of tectono-magmatic activity of the Gourougou magmatic field.

  7. Establishment of Lipolexis oregmae (Hymenoptera: Aphidiidae) in a classical biological control program directed against the brown citrus aphid (Homoptera: Aphididae) in Florida

    SciTech Connect

    Persad, A.B.; Hoy, M.A.; Ru Nguyen

    2007-03-15

    Guam, evaluado en cuarentena, criado en masa y liberado en huertos de citricos en un programa de control biologico clasico dirigido contra el afido pardo de citricos, Toxoptera citricida Kirkaldy. Se hicieron liberaciones de 20,200, 12,100, y 1,260 adultos de L. oregmae a traves de la Florida durante los anos de 2000, 2001, y 2002, respectivamente. Para determinar si L. oregmae ha logrado en establecer, se realizaron sondeos a traves del estado empezando en el verano del 2001 y continuando hasta el final del verano del 2003. El parasitismo durante 2001 y 2002 fue evaluado con el mantenimiento de individuos del afido pardo de los citricos en el laboratorio hasta que los adultos emergieron. Lipolexis oregmae fue encontrado en 10 sitios en 7 condados y con tasas de parasitismo en 4 sitios en 3 condados entre 0.7 a 3.3% en el 2001 y 2002, respectivamente. Las pruebas del laboratorio indicaron que las tasas altas de mortalidad fueron posibles si los afidos con parasitos recolectados en el campo fueron mantenidos en bolsas plasticas, entonces un ensayo molecular fue usado con lo que permitio la deteccion de inmaduros de L. oregmae dentro de los hospederos de afidos inmediatamente despues de la recoleccion. El ensayo molecular fue usado en el 2003 con individuos del afido pardo de los citricos y con otras especies de afidos recolectados sobre citricos, malezas y hortalizas cerca de los sitios donde los parasitoides fueron liberados anteriormente; inmaduros de L. oregmae fueron detectados en individuos del afido negro de los citricos, el afido del caupi, el afido spirea y el afido del melon, ademas del afido pardo de los citricos en 4 de los 8 condados muestreados, con la tasa del parasitismo entre 2.0 a12.9%, indicando que L. oregmae estaba estabecido y ampliamente distribuido. Las muestras tomadas en el Condado de Polk durante octobre del 2005 indicaron que L. oregmae ha persistido. La capacidad de L. oregmae para parasitar otras especies de afidos sobre citricos y otros

  8. Protein fragment bimolecular fluorescence complementation analyses for the in vivo study of protein-protein interactions and cellular protein complex localizations.

    PubMed

    Waadt, Rainer; Schlücking, Kathrin; Schroeder, Julian I; Kudla, Jörg

    2014-01-01

    The analyses of protein-protein interactions are crucial for understanding cellular processes including signal transduction, protein trafficking, and movement. Protein fragment complementation assays are based on the reconstitution of protein function when non-active protein fragments are brought together by interacting proteins that were genetically fused to these protein fragments. Bimolecular fluorescence complementation (BiFC) relies on the reconstitution of fluorescent proteins and enables both the analysis of protein-protein interactions and the visualization of protein complex formations in vivo. Transient expression of proteins is a convenient approach to study protein functions in planta or in other organisms and minimizes the need for time-consuming generation of stably expressing transgenic organisms. Here we describe protocols for BiFC analyses in Nicotiana benthamiana and Arabidopsis thaliana leaves transiently transformed by Agrobacterium infiltration. Further, we discuss different BiFC applications and provide examples for proper BiFC analyses in planta. PMID:24057390

  9. GenoCAD Plant Grammar to Design Plant Expression Vectors for Promoter Analysis.

    PubMed

    Coll, Anna; Wilson, Mandy L; Gruden, Kristina; Peccoud, Jean

    2016-01-01

    With the rapid advances in prediction tools for discovery of new promoters and their cis-elements, there is a need to improve plant expression methodologies in order to facilitate a high-throughput functional validation of these promoters in planta. The promoter-reporter analysis is an indispensible approach for characterization of plant promoters. It requires the design of complex plant expression vectors, which can be challenging. Here, we describe the use of a plant grammar implemented in GenoCAD that will allow the users to quickly design constructs for promoter analysis experiments but also for other in planta functional studies. The GenoCAD plant grammar includes a library of plant biological parts organized in structural categories to facilitate their use and management and a set of rules that guides the process of assembling these biological parts into large constructs. PMID:27557770

  10. Carnosic acid.

    PubMed

    Birtić, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc

    2015-07-01

    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (∼70 years ago) and its identification (∼50 years ago), numerous articles and patents (∼400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. PMID:25639596

  11. Biosynthesis of the antimetabolite 6-thioguanine in Erwinia amylovora plays a key role in fire blight pathogenesis.

    PubMed

    Coyne, Sébastien; Chizzali, Cornelia; Khalil, Mohammed N A; Litomska, Agnieszka; Richter, Klaus; Beerhues, Ludger; Hertweck, Christian

    2013-09-27

    Sulfur for fire: The molecular basis for the biosynthesis of the antimetabolite 6-thioguanine (6TG) was unveiled in Erwinia amylovora, the causative agent of fire blight. Bioinformatics, heterologous pathway reconstitution in E. coli, and mutational analyses indicate that the protein YcfA mediates guanine thionation in analogy to 2-thiouridylase. Assays in planta and in cell cultures reveal for the first time a crucial role of 6TG in fire blight pathogenesis. PMID:24038828

  12. Fluorescence-Activated Nucleolus Sorting in Arabidopsis.

    PubMed

    Pontvianne, Frédéric; Boyer-Clavel, Myriam; Sáez-Vásquez, Julio

    2016-01-01

    Nucleolar isolation allows exhaustive characterization of the nucleolar content. Centrifugation-based protocols are not adapted to isolation of nucleoli directly from a plant tissue because of copurification of cellular debris. We describe here a method that allows the purification of nucleoli using fluorescent-activated cell sorting from Arabidopsis thaliana leaves. This approach requires the expression of a specific nucleolar protein such as fibrillarin fused to green fluorescent protein in planta. PMID:27576720

  13. Global Pattern of Gene Expression of Xanthomonas axonopodis pv. glycines Within Soybean Leaves.

    PubMed

    Chatnaparat, Tiyakhon; Prathuangwong, Sutruedee; Lindow, Steven E

    2016-06-01

    To better understand the behavior of Xanthomonas axonopodis pv. glycines, the causal agent of bacterial pustule of soybean within its host, its global transcriptome within soybean leaves was compared with that in a minimal medium in vitro, using deep sequencing of mRNA. Of 5,062 genes predicted from a draft genome of X. axonopodis pv. glycines, 534 were up-regulated in the plant, while 289 were down-regulated. Genes encoding YapH, a cell-surface adhesin, as well as several others encoding cell-surface proteins, were down-regulated in soybean. Many genes encoding the type III secretion system and effector proteins, cell wall-degrading enzymes and phosphate transporter proteins were strongly expressed at early stages of infection. Several genes encoding RND multidrug efflux pumps were induced in planta and by isoflavonoids in vitro and were required for full virulence of X. axonopodis pv. glycines, as well as resistance to soybean phytoalexins. Genes encoding consumption of malonate, a compound abundant in soybean, were induced in planta and by malonate in vitro. Disruption of the malonate decarboxylase operon blocked growth in minimal media with malonate as the sole carbon source but did not significantly alter growth in soybean, apparently because genes for sucrose and fructose uptake were also induced in planta. Many genes involved in phosphate metabolism and uptake were induced in planta. While disruption of genes encoding high-affinity phosphate transport did not alter growth in media varying in phosphate concentration, the mutants were severely attenuated for growth in soybean. This global transcriptional profiling has provided insight into both the intercellular environment of this soybean pathogen and traits used by X. axonopodis pv. glycines to promote disease. PMID:27003800

  14. RT-PCR DETECTION OF CITRUS LEPROSIS VIRUS IN SHRUBS AND WEED PLANTS INFECTED THROUGH Brevipalpus phoenicis (ACARI: TENUIPALPIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    No Brasil são gastos anualmente cerca de US$ 80 milhões para controle de Brevipalpus phoenicis, vetor do vírus leprose dos citros (CiLV). Este ácaro possui comportamento polífago e cosmopolita, presente em inúmeras espécies de plantas junto aos pomares cítricos. Neste trabalho foi investigada a poss...

  15. Novel system for the simultaneous analysis of geminivirus DNA replication and plant interactions in Nicotiana benthamiana.

    PubMed

    Hong, Yiguo; Stanley, John; van Wezel, Rene

    2003-12-01

    The origin of replication of African cassava mosaic virus (ACMV) and a gene expression vector based on Potato virus X were exploited to devise an in planta system for functional analysis of the geminivirus replication-associated protein (Rep) in transgenic Nicotiana benthamiana line pOri-2. This line contains an integrated copy of a tandem repeat of the ACMV origin of replication flanking nonviral sequences that can be mobilized and replicated by Rep as an episomal replicon. A Rep-GFP fusion protein can also mobilize and amplify the replicon, facilitating Rep detection in planta. The activity of Rep and its mutants, Rep-mediated host response, and the correlation between Rep intracellular localization and biological functions could be effectively assessed by using this in planta system. Our results indicate that modification of amino acid residues R(2), R(5), R(7) and K(11) or H(56), L(57) and H(58) prevent Rep function in replication. This defect correlates with possible loss of Rep nuclear localization and inability to trigger the host defense mechanism resembling a hypersensitive response. PMID:14645587

  16. Structural Modifications and Programmed Cell Death of Chili Pepper Fruit Related to Resistance Responses to Colletotrichum gloeosporioides Infection.

    PubMed

    Kim, Kwang-Hyung; Yoon, Jae-Bok; Park, Hyo-Guen; Park, Eun Woo; Kim, Young Ho

    2004-12-01

    ABSTRACT Postharvest (detached) and in planta (attached) fruits of pepper plants, Capsicum annuum cv. Jejujaerae (susceptible) and Capsicum baccatum cv. PBC80 (resistant), inoculated with the anthracnose pathogen Colletotrichum gloeosporioides were examined using light, confocal laser scanning, and electron microscopy to compare the cytological differences between the compatible and incompatible interactions. In nonwound inoculation of postharvest pepper fruit, resistant pepper tissues showed a significant increase in the thickness of the cuticle layer compared with that of the susceptible and noninoculated fruit. Cytological features of programmed cell death (PCD) were observed in the resistant pepper fruit with postharvest inoculation, and these were characterized by positive responses to terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. The oligonucleosomal fragments of DNA were confirmed electrophoretically as DNA laddering. The PCD-positive responses occurred around the inoculation sites early in in planta wound inoculation in the resistant pepper. Nuclear modifications and structural changes of hypersensitivity were also observed in the resistant fruit, including separation of the plasma membrane from the cell wall, dilation of the endoplasmic reticulum, accumulation of electron-dense inclusions in vacuoles, and cytoplasmic vacuolization accompanying fragmentation of the cytoplasm. These structural changes may also implicate PCD-like host responses. In addition, in planta wound inoculation resulted in cell enlargement and cell division during the later stages of infection to form a periderm-like boundary layer around the inoculation site. PMID:18943699

  17. Plant and animal glycolate oxidases have a common eukaryotic ancestor and convergently duplicated to evolve long-chain 2-hydroxy acid oxidases.

    PubMed

    Esser, Christian; Kuhn, Anke; Groth, Georg; Lercher, Martin J; Maurino, Veronica G

    2014-05-01

    Glycolate oxidase (GOX) is a crucial enzyme of plant photorespiration. The encoding gene is thought to have originated from endosymbiotic gene transfer between the eukaryotic host and the cyanobacterial endosymbiont at the base of plantae. However, animals also possess GOX activities. Plant and animal GOX belong to the gene family of (L)-2-hydroxyacid-oxidases ((L)-2-HAOX). We find that all (L)-2-HAOX proteins in animals and archaeplastida go back to one ancestral eukaryotic sequence; the sole exceptions are green algae of the chlorophyta lineage. Chlorophyta replaced the ancestral eukaryotic (L)-2-HAOX with a bacterial ortholog, a lactate oxidase that may have been obtained through the primary endosymbiosis at the base of plantae; independent losses of this gene may explain its absence in other algal lineages (glaucophyta, rhodophyta, and charophyta). We also show that in addition to GOX, plants possess (L)-2-HAOX proteins with different specificities for medium- and long-chain hydroxyacids (lHAOX), likely involved in fatty acid and protein catabolism. Vertebrates possess lHAOX proteins acting on similar substrates as plant lHAOX; however, the existence of GOX and lHAOX subfamilies in both plants and animals is not due to shared ancestry but is the result of convergent evolution in the two most complex eukaryotic lineages. On the basis of targeting sequences and predicted substrate specificities, we conclude that the biological role of plantae (L)-2-HAOX in photorespiration evolved by co-opting an existing peroxisomal protein. PMID:24408912

  18. SLAH1, a homologue of the slow type anion channel SLAC1, modulates shoot Cl− accumulation and salt tolerance in Arabidopsis thaliana

    PubMed Central

    Qiu, Jiaen; Henderson, Sam W; Tester, Mark; Roy, Stuart J; Gilliham, Mathew

    2016-01-01

    Salinity tolerance is correlated with shoot chloride (Cl–) exclusion in multiple crops, but the molecular mechanisms of long-distance Cl– transport are poorly defined. Here, we characterize the in planta role of AtSLAH1 (a homologue of the slow type anion channel-associated 1 (SLAC1)). This protein, localized to the plasma membrane of root stelar cells, has its expression reduced by salt or ABA, which are key predictions for a protein involved with loading Cl– into the root xylem. Artificial microRNA knockdown mutants of AtSLAH1 had significantly reduced shoot Cl− accumulation when grown under low Cl–, whereas shoot Cl– increased and the shoot nitrate/chloride ratio decreased following AtSLAH1 constitutive or stelar-specific overexpression when grown in high Cl–. In both sets of overexpression lines a significant reduction in shoot biomass over the null segregants was observed under high Cl– supply, but not low Cl– supply. Further in planta data showed AtSLAH3 overexpression increased the shoot nitrate/chloride ratio, consistent with AtSLAH3 favouring nitrate transport. Heterologous expression of AtSLAH1 in Xenopus laevis oocytes led to no detectible transport, suggesting the need for post-translational modifications for AtSLAH1 to be active. Our in planta data are consistent with AtSLAH1 having a role in controlling root-to-shoot Cl– transport. PMID:27340232

  19. SLAH1, a homologue of the slow type anion channel SLAC1, modulates shoot Cl- accumulation and salt tolerance in Arabidopsis thaliana.

    PubMed

    Qiu, Jiaen; Henderson, Sam W; Tester, Mark; Roy, Stuart J; Gilliham, Mathew

    2016-08-01

    Salinity tolerance is correlated with shoot chloride (Cl(-)) exclusion in multiple crops, but the molecular mechanisms of long-distance Cl(-) transport are poorly defined. Here, we characterize the in planta role of AtSLAH1 (a homologue of the slow type anion channel-associated 1 (SLAC1)). This protein, localized to the plasma membrane of root stelar cells, has its expression reduced by salt or ABA, which are key predictions for a protein involved with loading Cl(-) into the root xylem. Artificial microRNA knockdown mutants of AtSLAH1 had significantly reduced shoot Cl(-) accumulation when grown under low Cl(-), whereas shoot Cl(-) increased and the shoot nitrate/chloride ratio decreased following AtSLAH1 constitutive or stelar-specific overexpression when grown in high Cl(-) In both sets of overexpression lines a significant reduction in shoot biomass over the null segregants was observed under high Cl(-) supply, but not low Cl(-) supply. Further in planta data showed AtSLAH3 overexpression increased the shoot nitrate/chloride ratio, consistent with AtSLAH3 favouring nitrate transport. Heterologous expression of AtSLAH1 in Xenopus laevis oocytes led to no detectible transport, suggesting the need for post-translational modifications for AtSLAH1 to be active. Our in planta data are consistent with AtSLAH1 having a role in controlling root-to-shoot Cl(-) transport. PMID:27340232

  20. Emission of herbivore elicitor-induced sesquiterpenes is regulated by stomatal aperture in maize (Zea mays) seedlings.

    PubMed

    Seidl-Adams, I; Richter, A; Boomer, K B; Yoshinaga, N; Degenhardt, J; Tumlinson, J H

    2015-01-01

    Maize seedlings emit sesquiterpenes during the day in response to insect herbivory. Parasitoids and predators use induced volatile blends to find their hosts or prey. To investigate the diurnal regulation of biosynthesis and emission of induced sesquiterpenes, we applied linolenoyl-L-glutamine (LG) to maize seedlings in the morning or evening using a cut-stem assay and tracked farnesene emission, in planta accumulation, as well as transcript levels of farnesyl pyrophosphate synthase 3 (ZmFPPS3) and terpene synthase10 (ZmTPS10) throughout the following day. Independent of time of day of LG treatment, maximum transcript levels of ZmFPPS3 and ZmTPS10 occurred within 3-4 h after elicitor application. The similarity between the patterns of farnesene emission and in planta accumulation in light-exposed seedlings in both time courses suggested unobstructed emission in the light. After evening induction, farnesene biosynthesis increased dramatically during early morning hours. Contrary to light-exposed seedlings dark-kept seedlings retained the majority of the synthesized farnesene. Two treatments to reduce stomatal aperture, dark exposure at midday, and abscisic acid treatment before daybreak, resulted in significantly reduced amounts of emitted and significantly increased amounts of in planta accumulating farnesene. Our results suggest that stomata not only play an important role in gas exchange for primary metabolism but also for indirect plant defences. PMID:24725255

  1. Using environmental isotopes in the study of the recharge-discharge mechanisms of the Yarmouk catchment area in Jordan

    NASA Astrophysics Data System (ADS)

    Salameh, Elias

    groundwater, which, from the highlands towards the Jordan Valley, shows increasing enrichment in isotopes. The highlands aquifer, with its groundwater depleted in isotopes, becomes confined towards the Jordan Valley; and, due to its confining pressure, leaks water upwards into the overlying aquifers causing their water to become less enriched in isotopes. Water depleted in its isotopic composition also seeps upward to the ground surface at the mountain foothills through faults and fissures. Les zones de recharge, les mécanismes d'écoulement et les zones de décharges des différentes masses d'eau souterraine sous le bassin versant de la rivière Yarmouk en Jordanie, étaient expliquées de manière ambiguë par les seuls outils isotopiques. Le long de la parti Jordanienne du bassin versant de la rivière Yarmouk l'eau souterraine provient de différents aquifères et se distinguent par leur type et leur composition chimique, selon que l'eau provient du même ou des différents aquifères. Les mécanismes conventionnels de recharge et de décharge, bilan hydrologique ne donnaient pas d'explications satisfaisantes concernant les variations chimiques et les différents types d'eau. En appliquant les isotopes environnementaux combinés aux effets de l'altitude sur les variations des teneurs isotopiques (l'altitude varie de 250 à 1,300 m sur une distance de 20 km.) et en prenant en considération les effets de ré-évaporation sur l'appauvrissement et l'enrichissement isotopique des eaux pluviales ont fortement contribués à une meilleure compréhension des mécanismes de recharge des différents aquifères. Les précipitations annuelles sont comprises entre 600 mm dans les zones en altitude et 350 mm dans la vallée de la Jordanie. Les écoulements de l'eau souterraine sont dirigés des zones en altitude vers la vallée de la Jordanie. Les eaux souterraines des zones en altitude sont isotopiquement appauvries (δO18 = -6, δD = -30), les eaux souterraines des zones de moyenne

  2. Foco Nasmyth para el telescopio 2,15mts. de CASLEO

    NASA Astrophysics Data System (ADS)

    Casagrande, A. R.

    En principio, este proyecto intenta lograr el mayor aprovechamiento posible del instrumental que se dispone, buscando la manera de optimizar y hacer más eficiente el servicio que brinda el CASLEO a la comunidad astronómica. El mismo consiste en utilizar dispositivos ya existentes en el telescopio, y darle una utilidad. Tal es el caso del camino óptico destinado al foco Coude. Si tenemos en cuenta que disponemos de un tercer espejo Coude, con todos sus mecanismos automatizados, (actualmente sin uso), una distancia apropiada del plano focal, el espacio y el lugar físico necesario para instalar un periférico, es posible la habilitación de un foco Nasmyth en el telescopio 2,15mts. El hecho de contar con este nuevo foco, redundará en importantes beneficios. En primer lugar, posibilitará la observación, casi simultánea, con dos instrumentos. Otro aspecto a tener en cuenta, es que disminuirá el frecuente cambio del instrumental periférico, motivo este que degrada su ideal puesta a punto. Por último, también de interés, es de destacar su escaso costo de ejecución.

  3. Teleconferences and Audiovisual Materials in Earth Science Education

    NASA Astrophysics Data System (ADS)

    Cortina, L. M.

    2007-05-01

    Unidad de Educacion Continua y a Distancia, Universidad Nacional Autonoma de Mexico, Coyoaca 04510 Mexico, MEXICO As stated in the special session description, 21st century undergraduate education has access to resources/experiences that go beyond university classrooms. However in some cases, resources may go largely unused and a number of factors may be cited such as logistic problems, restricted internet and telecommunication service access, miss-information, etc. We present and comment on our efforts and experiences at the National University of Mexico in a new unit dedicated to teleconferences and audio-visual materials. The unit forms part of the geosciences institutes, located in the central UNAM campus and campuses in other States. The use of teleconference in formal graduate and undergraduate education allows teachers and lecturers to distribute course material as in classrooms. Course by teleconference requires learning and student and teacher effort without physical contact, but they have access to multimedia available to support their exhibition. Well selected multimedia material allows the students to identify and recognize digital information to aid understanding natural phenomena integral to Earth Sciences. Cooperation with international partnerships providing access to new materials and experiences and to field practices will greatly add to our efforts. We will present specific examples of the experiences that we have at the Earth Sciences Postgraduate Program of UNAM with the use of technology in the education in geosciences.

  4. Dispersión de velocidades en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Muriel, H.; García Lambas, D.; Quintana, H.; Infante, L.

    Se ha estudiado la dinámica de galaxias en cúmulos en base a una muestra de aproximadamente 4000 galaxias con estimas de velocidad radial pertenecientes a 40 cúmulos. Se desarrolló un algoritmo para identificar sub-estructuras del tipo ``grupos de galaxias". Una vez eliminada este tipo de sub-estructura se computaron los perfiles radiales de dispersión de velocidades (VDP) para los 40 cúmulos de galaxias. Dada las características de la muestra, fue posible estimar el VDP hasta grandes distancias del centro del cúmulo llegando en algunos casos hasta 7 Mpc-1. Los resultados indican que el 65% de los cúmulos presentan un VDP plano a grandes radios consistente con el modelo isotermo. Estos resultados son discutidos en el marco de las recientes controversias suscitadas respecto de la dinámica de los cúmulos vía los perfiles de temperaturas de cúmulos derivados de la emisión en rayos-X.

  5. Telescopio Solar en Hα (HASTA)

    NASA Astrophysics Data System (ADS)

    Fernández Borda, R.; Francile, C.; Bagala, G.; Bauer, O.; Haerendel, G.; Rieger, E.; Rovira, M.

    El Telescopio Solar en Hα (Hα Solar Telescope for Argentina (-HASTA-) fue recientemente instalado en la Estación Astronómica de Altura Carlos Ulrrico Cesco (OAFA) en El Leoncito. Este instrumento estudiará la evolución de las fulguraciones solares desde tierra con alta resolución temporal y espacial. HASTA es un telescopio refractor de 110 mm con una distancia focal de 165 cm, un filtro Lyot sintonizable (±1Å) con un ancho de banda de 0.3 Å y una cámara CCD de alta resolución (1280×1024 pixels). Todo el conjunto es controlado en forma remota por una PC, la cual además adquiere datos del Sistema de Posicionamiento Global (GPS) y de la estación meteorológica. Diseñado para detectar fulguraciones, el instrumento trabaja en dos modos (patrullaje y fulguración) con una resolución espacial de 1.5 arcseg por pixel y una resolución temporal de 2 seg. HASTA comenzó a operar en Mayo de 1998 y, junto con otros tres instrumentos solares, que se están instalando o se instalaron, harán de El Leoncito un polo de observación solar importante en el Hemisferio Sur.

  6. Reductions in entree energy density increase children's vegetable intake and reduce energy intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The energy density (ED; kcal/g) of an entrée influences children's energy intake (EI), but the effect of simultaneously changing both ED and portion size of an entrée on preschool children's EI is unknown. In this within-subject crossover study, 3- to 5-year-old children (30 boys, 31 girls) in a day...

  7. Informe Anual a la Nación sobre el Cáncer de 1975 a 2008: preguntas y respuestas

    Cancer.gov

    Los índices generales de mortalidad por cáncer han seguido disminuyendo desde principios de los noventa entre hombres, mujeres y niños. Los índices de mortalidad disminuyeron en promedio 1,6% por año entre 2004 y 2008.

  8. Vegetable Purée: A Pilot Study to Increase Vegetable Consumption among School Lunch Participants in US Elementary Schools

    ERIC Educational Resources Information Center

    Vale, Angela; Schumacher, Julie Raeder; Cullen, Robert W.; Gam, Hae Jin

    2014-01-01

    Purpose/Objectives: Recent US Department of Agriculture regulations increased the amount and variety of vegetables required for school lunches. Vegetables are the most wasted components of lunch while entrées are selected and consumed by the majority of children. This study examined how adding vegetable purée to an elementary school lunch entrée…

  9. Healing war wounds and perfuming exile: the use of vegetal, animal, and mineral products for perfumes, cosmetics, and skin healing among Sahrawi refugees of Western Sahara

    PubMed Central

    2012-01-01

    exilio: el uso de productos vegetales, animales y minerales con fines de perfumería, cosmética y curativos de la piel entre los refugiados saharauis del Sáhara Occidental. Antecedentes Durante la última década ha habido un creciente interés en los estudios etnobiológicos de los conocimientos y prácticas de las personas que migran. Dentro de esta tendencia, los estudiosos han prestado relativamente menor atención a las personas desplazadas y a los refugiados: a la pérdida, el mantenimiento y la adaptación de sus conocimientos etnobiológicos, y su importancia para el bienestar de los refugiados. Este estudio se centra en los cosméticos y remedios para curar problemas de la piel tradicionalmente utilizados por los refugiados saharauis en los campamentos de desplazados al sudoeste de Argelia. Métodos Los métodos de investigación que se utilizaron son: una encuesta estructurada con 37 familias de refugiados, entrevistas semi-estructuradas con 77 refugiados, 24 entrevistas retrospectivas con refugiados e informantes conocedores, y una colección de muestra de las plantas y productos citados. Resultados Se registró el uso de 55 especies vegetales, nueve especies animales, y seis productos minerales utilizados en tres principales categorías de usos: 1) Recursos contra los problemas de salud característicos del entorno desértico donde una vez vivieron los saharauis como nómadas y donde ahora viven como refugiados (por ejemplo problemas en los ojos); 2) Remedios para heridas que reflejan la historia reciente de guerra de guerrilla de los nómadas saharauis; y 3) Cosméticos y productos utilizados para el cuidado del cuerpo, decoración y perfumes (por ejemplo, atención al cabello, limpieza de dientes, uso del henna) y como aromatizantes del aire al interior de las tiendas, que son ampliamente utilizados en la vida y las prácticas sociales cotidianas de los refugiados. Conclusiones En la discusión, se analizan los cambios qu

  10. Revised Phylogeny and Novel Horizontally Acquired Virulence Determinants of the Model Soft Rot Phytopathogen Pectobacterium wasabiae SCC3193

    PubMed Central

    Koskinen, Patrik; Nokso-Koivisto, Jussi; Pasanen, Miia; Broberg, Martin; Plyusnin, Ilja; Törönen, Petri; Holm, Liisa; Pirhonen, Minna; Palva, E. Tapio

    2012-01-01

    Soft rot disease is economically one of the most devastating bacterial diseases affecting plants worldwide. In this study, we present novel insights into the phylogeny and virulence of the soft rot model Pectobacterium sp. SCC3193, which was isolated from a diseased potato stem in Finland in the early 1980s. Genomic approaches, including proteome and genome comparisons of all sequenced soft rot bacteria, revealed that SCC3193, previously included in the species Pectobacterium carotovorum, can now be more accurately classified as Pectobacterium wasabiae. Together with the recently revised phylogeny of a few P. carotovorum strains and an increasing number of studies on P. wasabiae, our work indicates that P. wasabiae has been unnoticed but present in potato fields worldwide. A combination of genomic approaches and in planta experiments identified features that separate SCC3193 and other P. wasabiae strains from the rest of soft rot bacteria, such as the absence of a type III secretion system that contributes to virulence of other soft rot species. Experimentally established virulence determinants include the putative transcriptional regulator SirB, two partially redundant type VI secretion systems and two horizontally acquired clusters (Vic1 and Vic2), which contain predicted virulence genes. Genome comparison also revealed other interesting traits that may be related to life in planta or other specific environmental conditions. These traits include a predicted benzoic acid/salicylic acid carboxyl methyltransferase of eukaryotic origin. The novelties found in this work indicate that soft rot bacteria have a reservoir of unknown traits that may be utilized in the poorly understood latent stage in planta. The genomic approaches and the comparison of the model strain SCC3193 to other sequenced Pectobacterium strains, including the type strain of P. wasabiae, provides a solid basis for further investigation of the virulence, distribution and phylogeny of soft rot

  11. Revised phylogeny and novel horizontally acquired virulence determinants of the model soft rot phytopathogen Pectobacterium wasabiae SCC3193.

    PubMed

    Nykyri, Johanna; Niemi, Outi; Koskinen, Patrik; Nokso-Koivisto, Jussi; Pasanen, Miia; Broberg, Martin; Plyusnin, Ilja; Törönen, Petri; Holm, Liisa; Pirhonen, Minna; Palva, E Tapio

    2012-01-01

    Soft rot disease is economically one of the most devastating bacterial diseases affecting plants worldwide. In this study, we present novel insights into the phylogeny and virulence of the soft rot model Pectobacterium sp. SCC3193, which was isolated from a diseased potato stem in Finland in the early 1980s. Genomic approaches, including proteome and genome comparisons of all sequenced soft rot bacteria, revealed that SCC3193, previously included in the species Pectobacterium carotovorum, can now be more accurately classified as Pectobacterium wasabiae. Together with the recently revised phylogeny of a few P. carotovorum strains and an increasing number of studies on P. wasabiae, our work indicates that P. wasabiae has been unnoticed but present in potato fields worldwide. A combination of genomic approaches and in planta experiments identified features that separate SCC3193 and other P. wasabiae strains from the rest of soft rot bacteria, such as the absence of a type III secretion system that contributes to virulence of other soft rot species. Experimentally established virulence determinants include the putative transcriptional regulator SirB, two partially redundant type VI secretion systems and two horizontally acquired clusters (Vic1 and Vic2), which contain predicted virulence genes. Genome comparison also revealed other interesting traits that may be related to life in planta or other specific environmental conditions. These traits include a predicted benzoic acid/salicylic acid carboxyl methyltransferase of eukaryotic origin. The novelties found in this work indicate that soft rot bacteria have a reservoir of unknown traits that may be utilized in the poorly understood latent stage in planta. The genomic approaches and the comparison of the model strain SCC3193 to other sequenced Pectobacterium strains, including the type strain of P. wasabiae, provides a solid basis for further investigation of the virulence, distribution and phylogeny of soft rot

  12. Cathepsin B Cysteine Proteinase is Essential for the Development and Pathogenesis of the Plant Parasitic Nematode Radopholus similis

    PubMed Central

    Li, Yu; Wang, Ke; Xie, Hui; Wang, Dong-Wei; Xu, Chun-Ling; Huang, Xin; Wu, Wen-Jia; Li, Dan-Lei

    2015-01-01

    Radopholus similis is an important plant parasitic nematode which severely harms many crops. Cathepsin B is present in a wide variety of organisms, and plays an important role in many parasites. Understanding cathepsin B of R. similis would allow us to find new targets and approaches for its control. In this study, we found that Rs-cb-1 mRNA was expressed in esophageal glands, intestines and gonads of females, testes of males, juveniles and eggs in R. similis. Rs-cb-1 expression was the highest in females, followed by juveniles and eggs, and was the lowest in males. The maximal enzyme activity of Rs-CB-1 was detected at pH 6.0 and 40 °C. Silencing of Rs-cb-1 using in vitro RNAi (Soaking with dsRNA in vitro) not only significantly inhibited the development and hatching of R. similis, but also greatly reduced its pathogenicity. Using in planta RNAi, we confirmed that Rs-cb-1 expression in nematodes were significantly suppressed and the resistance to R. similis was significantly improved in T2 generation transgenic tobacco plants expressing Rs-cb-1 dsRNA. The genetic effects of in planta RNAi-induced gene silencing could be maintained in the absence of dsRNA for at least two generations before being lost, which was not the case for the effects induced by in vitro RNAi. Overall, our results first indicate that Rs-cb-1 plays key roles in the development, hatching and pathogenesis of R. similis, and that in planta RNAi is an effective tool in studying gene function and genetic engineering of plant resistance to migratory plant parasitic nematodes. PMID:26221074

  13. Aluminium-induced DNA damage and adaptive response to genotoxic stress in plant cells are mediated through reactive oxygen intermediates.

    PubMed

    Murali Achary, V Mohan; Panda, Brahma B

    2010-03-01

    Experiments employing growing root cells of Allium cepa were conducted with a view to elucidate the role of reactive oxygen intermediates (ROI) in aluminium (Al)-induced DNA damage, cell death and adaptive response to genotoxic challenge imposed by ethyl methanesulphonate (EMS) or methyl mercuric chloride (MMCl). In a first set of experiments, root cells in planta were treated with Al at high concentrations (200-800 microM) for 3 h without or with pre-treatments of dihydroxybenzene disulphonic acid (Tiron) and dimethylthiourea (DMTU) for 2 h that trap O(2)(.-)and hydrogen peroxide (H(2)O(2)), respectively. At the end of treatments, generation of O(2)(.-) and H(2)O(2), cell death and DNA damage were determined. In a second set of experiments, root cells in planta were conditioned by Al at low concentrations (5 or 10 microM) for 2 h and after a 2 h intertreatment interval challenged by MMCl or EMS for 3 h without or with a pre-treatment of Tiron or DMTU. Conditioning treatments, in addition, included two oxidative agents viz rose bengal and H(2)O(2) for comparison. Following treatments, root cells in planta were allowed to recover in tap water. Genotoxicity and DNA damage were evaluated by micronucleus (MN), chromosome aberration (CA) or spindle aberration (SA) and comet assays at different hours (0-30 h) of recovery. The results demonstrated that whereas Al at high concentrations induced DNA damage and cell death, in low concentrations induced adaptive response conferring genomic protection from genotoxic challenge imposed by MMCl, EMS and Al. Pre-treatments of Tiron and DMTU prevented Al-induced DNA damage, cell death, as well as genotoxic adaptation to MMCl and EMS, significantly. The findings underscored the biphasic (hormetic) mode of action of Al that at high doses induced DNA damage and at low non-toxic doses conferred genomic protection, both of which were mediated through ROI but perhaps involving different networks. PMID:19955331

  14. Lipid labeling from acetate or glycerol in cultured embryos of Camelina sativa seeds: A tale of two substrates.

    PubMed

    Pollard, Mike; Delamarter, Danielle; Martin, Tina M; Shachar-Hill, Yair

    2015-10-01

    Studies on the metabolism of lipids in seeds frequently use radiolabeled acetate and glycerol supplied to excised developing seeds to track the biosynthesis of acyl and lipid head groups, respectively. Such experiments are generally restricted to shorter time periods and the results may not quantitatively reflect in planta rates. These limitations can be removed by using cultured embryos, provided they mimic growth and lipid deposition observed for embryos in planta. Mid-maturation embryos from Camelina sativa were cultured in vitro to assess the use of sufficient acetate or glycerol concentrations and labeling periods for stable isotope labeling and mass spectrometric detection. Maximum incorporation of exogenous acetate into fatty acids occurred at 1mM and above. This provides about 5% of the total carbon flux entering fatty acids, enough for (13)C isotopomer analysis while maintaining normal biosynthetic rates for over 24h. Labeling analysis indicates that acetate reports lipid metabolism uniformly across the embryo. At higher acetate concentrations with longer incubations, the rate of fatty acid synthesis is reduced and the composition of newly synthesized fatty acids changes. While the mole fractions of oleate that undergo Δ12-desaturation or elongation are independent of biosynthetic flux, Δ15-desaturation shows a bimodal dependence. These observations are consistent with changes occurring in planta over seed development. Incorporation rates of the glyceryl moiety into lipids saturates at about 0.5mM exogenous glycerol. At saturation, the exogenous glycerol almost completely replaces the endogenous supply of glycerol-3-phosphate without affecting net lipid accumulation or fatty acid composition. It is concluded that acetate and glycerol labeling of cultured C. sativa embryos can provide an accurate representation of lipid metabolism in embryos in vivo, and that in Camelina embryos glycerol-3-phosphate levels do not co-limit triacylglycerol synthesis. PMID

  15. Evidence for widespread exonic small RNAs in the glaucophyte alga Cyanophora paradoxa.

    PubMed

    Gross, Jeferson; Wajid, Sana; Price, Dana C; Zelzion, Ehud; Li, Junyi; Chan, Cheong Xin; Bhattacharya, Debashish

    2013-01-01

    RNAi (RNA interference) relies on the production of small RNAs (sRNAs) from double-stranded RNA and comprises a major pathway in eukaryotes to restrict the propagation of selfish genetic elements. Amplification of the initial RNAi signal by generation of multiple secondary sRNAs from a targeted mRNA is catalyzed by RNA-dependent RNA polymerases (RdRPs). This phenomenon is known as transitivity and is particularly important in plants to limit the spread of viruses. Here we describe, using a genome-wide approach, the distribution of sRNAs in the glaucophyte alga Cyanophora paradoxa. C. paradoxa is a member of the supergroup Plantae (also known as Archaeplastida) that includes red algae, green algae, and plants. The ancient (>1 billion years ago) split of glaucophytes within Plantae suggests that C. paradoxa may be a useful model to learn about the early evolution of RNAi in the supergroup that ultimately gave rise to plants. Using next-generation sequencing and bioinformatic analyses we find that sRNAs in C. paradoxa are preferentially associated with mRNAs, including a large number of transcripts that encode proteins arising from different functional categories. This pattern of exonic sRNAs appears to be a general trend that affects a large fraction of mRNAs in the cell. In several cases we observe that sRNAs have a bias for a specific strand of the mRNA, including many instances of antisense predominance. The genome of C. paradoxa encodes four sequences that are homologous to RdRPs in Arabidopsis thaliana. We discuss the possibility that exonic sRNAs in the glaucophyte may be secondarily derived from mRNAs by the action of RdRPs. If this hypothesis is confirmed, then transitivity may have had an ancient origin in Plantae. PMID:23844054

  16. Expression and glycoengineering of functionally active heteromultimeric IgM in plants

    PubMed Central

    Loos, Andreas; Gruber, Clemens; Altmann, Friedrich; Mehofer, Ulrich; Hensel, Frank; Grandits, Melanie; Oostenbrink, Chris; Stadlmayr, Gerhard; Furtmüller, Paul G.; Steinkellner, Herta

    2014-01-01

    IgM antibodies are an important player of the human’s innate defense mechanisms and increasingly have gained interest as therapeutics. Although the expression of IgM antibodies in mammalian cell culture is established, this approach remains costly and alternative methods have not been developed yet. Plants have a proven record for the production of therapeutically relevant recombinant proteins. However, whether they are able to express proteins like IgM antibodies, which range among the most complex human proteins, remains unknown so far. Here we report the in planta generation of the functionally active monoclonal antitumor IgM PAT-SM6 (SM6). SM6 efficiently accumulates in plant leaves and assembles correctly into heterooligomers (pentamers and hexamers). Detailed glycosylation analysis exhibited complex and oligomannosidic N-glycans in a site-specific manner on human-serum IgM and on plant- and human-cell-line–produced SM6. Moreover, extensive in planta glycoengineering allowed the generation of SM6 decorated with sialylated human-type oligosaccharides, comparable to plasma-derived IgM. A glycosylated model of pentameric IgM exhibits different accessibility of the glycosylation sites, explaining site-specific glycosylation. Biochemical and biophysical properties and importantly biological activities of plant-derived SM6 glycoforms are comparable to the human-cell–derived counterparts. The in planta generation of one of the most complex human proteins opens new pathways toward the production of difficult-to-express proteins for pharmaceutical applications. Moreover, the generation of IgMs with a controlled glycosylation pattern allows the study of the so far unknown contribution of sugar moieties to the function of IgMs. PMID:24706782

  17. [Classification of Fungi in modern view].

    PubMed

    Agerer, R

    2003-01-01

    Fungi are a heterogeneous jumble coming together from three kingdoms of organisms. The True Fungi represent a kingdom of its own and are positioned closer to the Animalia than to the Plantae. At present the Fungi are divided into five Divisions. Species pathogenic for humans are found in the Divisions Zygomycota, Ascomycota and Basidiomycota. The Pneumocystidales are now classified in the Ascomycota. The Malasseziales are included in the Class Ustilaginomycetes. Essential characteristics for the classification of Fungi are derived from ultrastructure, chemistry, and more recently also from molecular biology of these organisms. None of these methods can stand for its own, all characteristics must be included. PMID:12955846

  18. PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

    PubMed

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frédéric; Nicolè, Florence; Raymond, Olivier; Huguet, Stéphanie; Baltenweck, Raymonde; Meyer, Sophie; Claudel, Patricia; Jeauffre, Julien; Rohmer, Michel; Foucher, Fabrice; Hugueney, Philippe; Bendahmane, Mohammed; Baudino, Sylvie

    2015-07-01

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta. PMID:26138978

  19. Dual Effect of the Cubic Ag3PO4 Crystal on Pseudomonas syringae Growth and Plant Immunity

    PubMed Central

    Kim, Mi Kyung; Yeo, Byul-Ee; Park, Heonyong; Huh, Young-Duk; Kwon, Chian; Yun, Hye Sup

    2016-01-01

    We previously found that the antibacterial activity of silver phosphate crystals on Escherichia coli depends on their structure. We here show that the cubic form of silver phosphate crystal (SPC) can also be applied to inhibit the growth of a plant-pathogenic Pseudomonas syringae bacterium. SPC pretreatment resulted in reduced in planta multiplication of P. syringae. Induced expression of a plant defense marker gene PR1 by SPC alone is suggestive of its additional plant immunity-stimulating activity. Since SPC can simultaneously inhibit P. syringae growth and induce plant defense responses, it might be used as a more effective plant disease-controlling agent. PMID:27147937

  20. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life

    NASA Technical Reports Server (NTRS)

    Margulis, L.

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae.

  1. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life.

    PubMed

    Margulis, L

    1996-02-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae. PMID:8577716

  2. Archaeal-eubacterial mergers in the origin of Eukarya: phylogenetic classification of life.

    PubMed Central

    Margulis, L

    1996-01-01

    A symbiosis-based phylogeny leads to a consistent, useful classification system for all life. "Kingdoms" and "Domains" are replaced by biological names for the most inclusive taxa: Prokarya (bacteria) and Eukarya (symbiosis-derived nucleated organisms). The earliest Eukarya, anaerobic mastigotes, hypothetically originated from permanent whole-cell fusion between members of Archaea (e.g., Thermoplasma-like organisms) and of Eubacteria (e.g., Spirochaeta-like organisms). Molecular biology, life-history, and fossil record evidence support the reunification of bacteria as Prokarya while subdividing Eukarya into uniquely defined subtaxa: Protoctista, Animalia, Fungi, and Plantae. Images Fig. 1 PMID:8577716

  3. Isolation of ribulose-1,5-bisphosphate carboxylase/oxygenase from leaves.

    PubMed

    Carmo-Silva, A Elizabete; Barta, Csengele; Salvucci, Michael E

    2011-01-01

    Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is a multifunctional enzyme that catalyzes the fixation of CO2 and O2 in photosynthesis and photorespiration, respectively. As the rate-limiting step in photosynthesis, improving the catalytic properties of Rubisco has long been viewed as a viable strategy for increasing plant productivity. Advances in biotechnology have made this goal more attainable by making it possible to modify Rubisco in planta. To properly evaluate the properties of Rubisco, it is necessary to isolate the enzyme in pure form. This chapter describes procedures for rapid and efficient purification of Rubisco from leaves of several species. PMID:20960141

  4. Laser-Based Methods for Detection of Nitric Oxide in Plants.

    PubMed

    Mandon, Julien; Mur, Luis A J; Harren, Frans J M; Cristescu, Simona M

    2016-01-01

    Nitric oxide (NO) plays an important role in plant signaling and in response to various stress conditions. Therefore, real-time measurements of NO production provide better insights into understanding plant processes and can help developing strategies to improve food production and postharvest quality. Using laser-based spectroscopic methods, sensitive, online, in planta measurements of plant-pathogen interactions are possible. This chapter introduces the basic principle of the optical detectors using different laser sources for accurate monitoring of fast dynamic changes of NO production. Several applications are also presented to demonstrate the suitability of these detectors for detection of NO in plants. PMID:27094415

  5. A High-Throughput Forward Genetic Screen Identifies Genes Required for Virulence of Pseudomonas syringae pv. maculicola ES4326 on Arabidopsis

    PubMed Central

    Schreiber, Karl J.; Ye, David; Fich, Eric; Jian, Allen; Lo, Timothy; Desveaux, Darrell

    2012-01-01

    Successful pathogenesis requires a number of coordinated processes whose genetic bases remain to be fully characterized. We utilized a high-throughput, liquid media-based assay to screen transposon disruptants of the phytopathogen Pseudomonas syringae pv. maculicola ES4326 to identify genes required for virulence on Arabidopsis. Many genes identified through this screen were involved in processes such as type III secretion, periplasmic glucan biosynthesis, flagellar motility, and amino acid biosynthesis. A small set of genes did not fall into any of these functional groups, and their disruption resulted in context-specific effects on in planta bacterial growth. PMID:22870224

  6. Extrapolate the Past... or Invent the Future

    ScienceCinema

    Vinod Khosla

    2010-01-08

    Berkeley Lab's Environmental Energy Technologies Division launches its Distinguished Lecturer series with a talk by Vinod Khosla, founder of Khosla Ventures, whose mission is to "assist great entre...  

  7. Giant Enhancement of Diffusion in a Tilted Egg-Carton Potential

    NASA Astrophysics Data System (ADS)

    Yang, Song; Jing-Dong, Bao

    2016-02-01

    Not Available Supported by the National Natural Science Foundation of China under Grant Nos 11575024 and 11175021, and the Plan of Beijing College Students' Scientific Research and EntrePrenurial Action under Grant No 105820.

  8. DEVELOPMENT OF SUPERIOR ENTRAINMENT SEPARATORS

    EPA Science Inventory

    An experimental and theoretical program was carried out to develop an improved design for entrainment separators for scrubbers. The problems of separation efficiency, suspended solids deposition and plugging of the entrainment separator were of primary concern. A pilot scale entr...

  9. Extrapolate the Past... or Invent the Future

    SciTech Connect

    Vinod Khosla

    2008-10-14

    Berkeley Lab's Environmental Energy Technologies Division launches its Distinguished Lecturer series with a talk by Vinod Khosla, founder of Khosla Ventures, whose mission is to "assist great entre...  

  10. Mecanismos cinéticos y distribuciones energéticas de iones (H3+, N2H+, CH3+...) en plasmas fríos de H2/N2/CH4

    NASA Astrophysics Data System (ADS)

    Tanarro, I.; Herrero, V. J.; Islyaikin, A.; Tabarés, F. L.; Tafalla, D.

    En este trabajo se presenta el estudio espectrométrico de los plasmas levemente ionizados generados en una descarga continua a baja presión de H2 con trazas de N2 y CH4, orientado principalmente a identificar la naturaleza y distribución energética de los iones que en ella se producen, y a asignar algunos de los mecanismos cinéticos elementales de formación y destrucción de tales especies. Alguno de los iones mayoritarios de estos plasmas, como el H3+, presenta gran interés desde el punto de vista de la Astrofísica por su prevista intervención en la química de las ionosferas planetarias y del medio interestelar, al actuar como sustancia intermedia en la formación de gran variedad de especies moleculares; si bien, dada su pequeña concentración, su observación real en el espacio se demoró hasta la pasada década de los años 90, cuando fue detectado por primera vez en la atmósfera de Júpiter y en otros objetos estelares. Del mismo modo que los trabajos espectroscópicos de laboratorio resultan indispensables para la posterior identificación de las especies observadas en el espacio, es de esperar que la asignación de los procesos cinéticos más importantes que tienen lugar en los plasmas generados en reactores de descarga, como los aquí presentados, permitan extrapolar los resultados así obtenidos al esclarecimiento de los mecanismos fisico-químicos participantes en otros medios observables únicamente a larga distancia.

  11. Sobrevivendo a un tsunami: lecciones de Chile, Hawai y Japon

    USGS Publications Warehouse

    Compilado por Atwater, Brian F.; Cisternas V., Marco; Bourgeois, Joanne; Dudley, Walter C.; Hendley, James W., II; Stauffer, Peter H.

    1999-01-01

    Este folleto contiene historias veridicas que ilustran como sobrevivir, y como no sobrevivir, a un tsunami. Esta publicacion esta dirigida a las personas que viven, trabajan o, simplemente, se divierten a lo largo de las costas que pueden ser afectadas por un tsunami. Tales costas rodean la mayor parte del Oceano Pacifico pero tambien incluyen algunas areas costeras de los Oceanos Atlantico e Indico. Aunque mucha gente llama a los tsunamis 'olas de marea', estos no estan relacionados a las mareas, sino son una serie de olas, o 'tren de olas', generalmente causadas por cambios en el nivel del fondo marino durante los terremotos. Los tsunamis tambien pueden ser generados por la erupcion de volcanes costeros, islas volconicas, deslizamientos submarinos e impactos de grandes meteoritos en el mar. Como sucedio en Sumatra en el 2004, los tsunamis pueden alcanzar alturas de 15 metros, no tan solo en la costa sino tambien kilometros tierra adentro. Los relatos presentados en este folleto fueron seleccionados de entrevistas realizadas a personas que sobrevivieron al tsunami del Oceano Pacifico de 1960. Muchas de estas personas, incluyendo a la enfermera de la foto, se enfrento a las olas generadas a poca distancia, en la costa chilena. En cambio, otros debieron hacer frente al tsunami muchas horas despues, en Hawai y Japon. La mayoria de las entrevistas fueron realizadas a fines de los anos ochenta y en los noventa. Las historias ofrecen una mezcla de lecciones de supervivencia a un tsunami. En algunos casos se presentan las acciones que confiablemente salvaron vidas: poner atencion a los avisos de la naturaleza, abandonar los bienes, dirigirse rapidamente a un sector alto y permanecer alli hasta que el tsunami realmente haya terminado. Otras historias describen como se encontro refugio al subir a construcciones y arboles o flotar sobre desechos, tacticas que tuvieron diferentes resultados y que pueden ser recomendadas solo como actos desesperados de personas atrapadas en

  12. Evaluation of a Voluntary Menu-Labeling Program in Full-Service Restaurants

    PubMed Central

    Leng, Kirsten

    2010-01-01

    Objectives. We assessed whether labeling restaurant menus with information on the nutrient content of menu items would cause customers to alter their ordering patterns. Methods. Six full-service restaurants in Pierce County, Washington, added nutrition information to their menus, and they provided data on entrée sales for 30 days before and 30 days after the information was added. We assessed the prelabeling versus postlabeling difference in nutrient content of entrées sold, and we surveyed restaurant patrons about whether they noticed the nutrition information and used it in their ordering. Results. The average postlabeling entrée sold contained about 15 fewer calories, 1.5 fewer grams of fat, and 45 fewer milligrams of sodium than did the average entrée sold before labeling. Seventy-one percent of patrons reported noticing the nutrition information; 20.4% reported ordering an entrée lower in calories as a result, and 16.5% reported ordering an entrée lower in fat as a result. Conclusions. The concentration of calorie reduction among 20.4% of patrons means that each calorie-reducing patron ordered about 75 fewer calories than they did before labeling. Thus, providing nutrition information on restaurant menus may encourage a subset of restaurant patrons to significantly alter their food choices. PMID:20395577

  13. Loss of the nodule-specific cysteine rich peptide, NCR169, abolishes symbiotic nitrogen fixation in the Medicago truncatula dnf7 mutant

    PubMed Central

    Horváth, Beatrix; Domonkos, Ágota; Szűcs, Attila; Ábrahám, Edit; Ayaydin, Ferhan; Bóka, Károly; Chen, Yuhui; Chen, Rujin; Murray, Jeremy D.; Udvardi, Michael K.; Kondorosi, Éva; Kaló, Péter

    2015-01-01

    Host compatible rhizobia induce the formation of legume root nodules, symbiotic organs within which intracellular bacteria are present in plant-derived membrane compartments termed symbiosomes. In Medicago truncatula nodules, the Sinorhizobium microsymbionts undergo an irreversible differentiation process leading to the development of elongated polyploid noncultivable nitrogen fixing bacteroids that convert atmospheric dinitrogen into ammonia. This terminal differentiation is directed by the host plant and involves hundreds of nodule specific cysteine-rich peptides (NCRs). Except for certain in vitro activities of cationic peptides, the functional roles of individual NCR peptides in planta are not known. In this study, we demonstrate that the inability of M. truncatula dnf7 mutants to fix nitrogen is due to inactivation of a single NCR peptide, NCR169. In the absence of NCR169, bacterial differentiation was impaired and was associated with early senescence of the symbiotic cells. Introduction of the NCR169 gene into the dnf7-2/NCR169 deletion mutant restored symbiotic nitrogen fixation. Replacement of any of the cysteine residues in the NCR169 peptide with serine rendered it incapable of complementation, demonstrating an absolute requirement for all cysteines in planta. NCR169 was induced in the cell layers in which bacteroid elongation was most pronounced, and high expression persisted throughout the nitrogen-fixing nodule zone. Our results provide evidence for an essential role of NCR169 in the differentiation and persistence of nitrogen fixing bacteroids in M. truncatula. PMID:26401023

  14. Loss of the nodule-specific cysteine rich peptide, NCR169, abolishes symbiotic nitrogen fixation in the Medicago truncatula dnf7 mutant.

    PubMed

    Horváth, Beatrix; Domonkos, Ágota; Kereszt, Attila; Szűcs, Attila; Ábrahám, Edit; Ayaydin, Ferhan; Bóka, Károly; Chen, Yuhui; Chen, Rujin; Murray, Jeremy D; Udvardi, Michael K; Kondorosi, Éva; Kaló, Péter

    2015-12-01

    Host compatible rhizobia induce the formation of legume root nodules, symbiotic organs within which intracellular bacteria are present in plant-derived membrane compartments termed symbiosomes. In Medicago truncatula nodules, the Sinorhizobium microsymbionts undergo an irreversible differentiation process leading to the development of elongated polyploid noncultivable nitrogen fixing bacteroids that convert atmospheric dinitrogen into ammonia. This terminal differentiation is directed by the host plant and involves hundreds of nodule specific cysteine-rich peptides (NCRs). Except for certain in vitro activities of cationic peptides, the functional roles of individual NCR peptides in planta are not known. In this study, we demonstrate that the inability of M. truncatula dnf7 mutants to fix nitrogen is due to inactivation of a single NCR peptide, NCR169. In the absence of NCR169, bacterial differentiation was impaired and was associated with early senescence of the symbiotic cells. Introduction of the NCR169 gene into the dnf7-2/NCR169 deletion mutant restored symbiotic nitrogen fixation. Replacement of any of the cysteine residues in the NCR169 peptide with serine rendered it incapable of complementation, demonstrating an absolute requirement for all cysteines in planta. NCR169 was induced in the cell layers in which bacteroid elongation was most pronounced, and high expression persisted throughout the nitrogen-fixing nodule zone. Our results provide evidence for an essential role of NCR169 in the differentiation and persistence of nitrogen fixing bacteroids in M. truncatula. PMID:26401023

  15. Characterization of IRE1 ribonuclease-mediated mRNA decay in plants using transient expression analyses in rice protoplasts.

    PubMed

    Hayashi, Shimpei; Wakasa, Yuhya; Ozawa, Kenjirou; Takaiwa, Fumio

    2016-06-01

    In some eukaryotes, endoplasmic reticulum (ER) stress induces regulated inositol-requiring enzyme 1 (IRE1)-dependent decay (RIDD) of mRNAs. Recently, the expression levels of the mRNAs encoding some secretory proteins were reported to be downregulated by RIDD in the vegetative tissues of plants. However, the characteristics of plant RIDD have been insufficiently investigated due to difficulty of in planta analyses. Here, the RIDD susceptibilities of various mRNAs that are difficult to analyze in planta were examined using transient expression analyses of rice protoplasts. In this system, the mRNAs encoding three rice seed storage proteins (SSPs) - namely α-globulin, 16-kDa prolamin and 10-kDa prolamin - were downregulated in response to ER stress. The rapid ER stress-induced degradation of these mRNAs was repressed in cells in which the ribonuclease activity of IRE1 was specifically abolished by genome editing, suggesting that the mRNAs encoding certain SSPs are strong targets of RIDD. Furthermore, we investigated whether these RIDD targets are substrates of the IRE1 ribonuclease using a recombinant IRE1 protein, and identified candidate IRE1-mediated cleavage sites. Overall, the results demonstrate the existence of a post-transcriptional mechanism of regulation of SSPs, and illustrate the basic and multifaceted characteristics of RIDD in higher plants. PMID:26831622

  16. Sugars as hydroxyl radical scavengers: proof-of-concept by studying the fate of sucralose in Arabidopsis.

    PubMed

    Matros, Andrea; Peshev, Darin; Peukert, Manuela; Mock, Hans-Peter; Van den Ende, Wim

    2015-06-01

    Substantial formation of reactive oxygen species (ROS) is inevitable in aerobic life forms. Due to their extremely high reactivity and short lifetime, hydroxyl radicals are a special case, because cells have not developed enzymes to detoxify these most dangerous ROS. Thus, scavenging of hydroxyl radicals may only occur by accumulation of higher levels of simple organic compounds. Previous studies have demonstrated that plant-derived sugars show hydroxyl radical scavenging capabilities during Fenton reactions with Fe(2+) and hydrogen peroxide in vitro, leading to formation of less detrimental sugar radicals that may be subject of regeneration to non-radical carbohydrates in vivo. Here, we provide further evidence for the occurrence of such radical reactions with sugars in planta, by following the fate of sucralose, an artificial analog of sucrose, in Arabidopsis tissues. The expected sucralose recombination and degradation products were detected in both normal and stressed plant tissues. Oxidation products of endogenous sugars were also assessed in planta for Arabidopsis and barley, and were shown to increase in abundance relative to the non-oxidized precursor during oxidative stress conditions. We concluded that such non-enzymatic reactions with hydroxyl radicals form an integral part of plant antioxidant mechanisms contributing to cellular ROS homeostasis, and may be more important than generally assumed. This is discussed in relation to the recently proposed roles for Fe(2+) and hydrogen peroxide in processes leading to the origin of metabolism and the origin of life. PMID:25891826

  17. Transactivation of dianthin transgene expression by African cassava mosaic virus AC2.

    PubMed

    Hong, Y; Saunders, K; Stanley, J

    1997-02-17

    We have recently described a novel strategy for engineering resistance to African cassava mosaic virus (ACMV) in transgenic Nicotiana benthamiana plants using a virus-inducible promoter to control the expression of a plant ribosome-inactivating protein (RIP) transgene (Y. Hong et al., Virology 220, 119-127, 1996). Here, we have used a potato virus X (PVX) vector to express the ACMV transactivator protein, AC2, in planta. We confirm that amplification of RIP activity in transgenic plants is mediated by AC2; disruption of AC2 expression by either the introduction of an in-frame stop codon or the deletion of 5'-terminal or 3'-terminal coding sequences reduced RIP expression to the basal level associated with PVX-infected plants. AC2 expression from the PVX vector induced necrosis in nontransformed plants as well as in plants containing the RIP transgene, suggesting that the protein can functionally interact with PVX and/or host factors. The potential of this system to provide a direct and sensitive assay to investigate AC2 function in planta is discussed. PMID:9123846

  18. Heterologous stable expression of terpenoid biosynthetic genes using the moss Physcomitrella patens.

    PubMed

    Bach, Søren Spanner; King, Brian Christopher; Zhan, Xin; Simonsen, Henrik Toft; Hamberger, Björn

    2014-01-01

    Heterologous and stable expression of genes encoding terpenoid biosynthetic enzymes in planta is an important tool for functional characterization and is an attractive alternative to expression in microbial hosts for biotechnological production. Despite improvements to the procedure, such as streamlining of large scale Agrobacterium infiltration and upregulation of the upstream pathways, transient in planta heterologous expression quickly reaches limitations when used for production of terpenoids. Stable integration of transgenes into the nuclear genome of the moss Physcomitrella patens has already been widely recognized as a viable alternative for industrial-scale production of biopharmaceuticals. For expression of terpenoid biosynthetic genes, and reconstruction of heterologous pathways, Physcomitrella has unique attributes that makes it a very promising biotechnological host. These features include a high native tolerance to terpenoids, a simple endogenous terpenoid profile, convenient genome editing using homologous recombination, and cultivation techniques that allow up-scaling from single cells in microtiter plates to industrial photo-bioreactors. Beyond its use for functional characterization of terpenoid biosynthetic genes, engineered Physcomitrella can be a green biotechnological platform for production of terpenoids. Here, we describe two complementary and simple procedures for stable nuclear transformation of Physcomitrella with terpenoid biosynthetic genes, selection and cultivation of transgenic lines, and metabolite analysis of terpenoids produced in transgenic moss lines. We also provide tools for metabolic engineering through genome editing using homologous recombination. PMID:24777804

  19. Polar Localizing Class V Myosin Chitin Synthases Are Essential during Early Plant Infection in the Plant Pathogenic Fungus Ustilago maydisW⃞

    PubMed Central

    Weber, Isabella; Aßmann, Daniela; Thines, Eckhard; Steinberg, Gero

    2006-01-01

    Fungal chitin synthases (CHSs) form fibers of the cell wall and are crucial for substrate invasion and pathogenicity. Filamentous fungi contain up to 10 CHSs, which might reflect redundant functions or the complex biology of these fungi. Here, we investigate the complete repertoire of eight CHSs in the dimorphic plant pathogen Ustilago maydis. We demonstrate that all CHSs are expressed in yeast cells and hyphae. Green fluorescent protein (GFP) fusions to all CHSs localize to septa, whereas Chs5-GFP, Chs6-GFP, Chs7-yellow fluorescent protein (YFP), and Myosin chitin synthase1 (Mcs1)-YFP were found at growth regions of yeast-like cells and hyphae, indicating that they participate in tip growth. However, only the class IV CHS genes chs7 and chs5 are crucial for shaping yeast cells and hyphae ex planta. Although most CHS mutants were attenuated in plant pathogenicity, Δchs6, Δchs7, and Δmcs1 mutants were drastically reduced in virulence. Δmcs1 showed no morphological defects in hyphae, but Mcs1 became essential during invasion of the plant epidermis. Δmcs1 hyphae entered the plant but immediately lost growth polarity and formed large aggregates of spherical cells. Our data show that the polar class IV CHSs are essential for morphogenesis ex planta, whereas the class V myosin-CHS is essential during plant infection. PMID:16314447

  20. Contrasting root associated fungi of three common oak-woodland plant species based on molecular identification: host specificity or non-specific amplification?

    PubMed

    Douhan, Greg W; Petersen, Carolyn; Bledsoe, Caroline S; Rizzo, David M

    2005-07-01

    An increasingly popular approach used to identify arbuscular mycorrhizal (AM) fungi in planta is to amplify a portion of AM fungal small subunit ribosomal DNA (SSU-rDNA) from whole root DNA extractions using the primer pair AM1-NS31, followed by cloning and sequencing. We used this approach to study the AM fungal community composition of three common oak-woodland plant species: a grass (Cynosurus echinatus), blue oak (Quercus douglasii), and a forb (Torilis arvensis). Significant diversity of AM fungi were found in the roots of C. echinatus, which is consistent with previous studies demonstrating a high degree of AM fungal diversity from the roots of various hosts. In contrast, clones from Q. douglasii and T. arvensis were primarily from non-AM fungi of diverse origins within the Ascomycota and Basidiomycota. This work demonstrates that caution must be taken when using this molecular approach to determine in planta AM fungal diversity if non-sequence based methods such as terminal restriction fragment length polymorphisms, denaturing gradient gel electrophoresis, or temperature gradient gel electrophoresis are used. PMID:15772816

  1. Evaluation of reference genes for real-time RT-PCR expression studies in the plant pathogen Pectobacterium atrosepticum

    PubMed Central

    Takle, Gunnhild W; Toth, Ian K; Brurberg, May B

    2007-01-01

    Background Real-time RT-PCR has become a powerful technique to monitor low-abundance mRNA expression and is a useful tool when examining bacterial gene expression inside infected host tissues. However, correct evaluation of data requires accurate and reliable normalisation against internal standards. Thus, the identification of reference genes whose expression does not change during the course of the experiment is of paramount importance. Here, we present a study where manipulation of cultural growth conditions and in planta experiments have been used to validate the expression stability of reference gene candidates for the plant pathogen Pectobacterium atrosepticum, belonging to the family Enterobacteriaceae. Results Of twelve reference gene candidates tested, four proved to be stably expressed both in six different cultural growth conditions and in planta. Two of these genes (recA and ffh), encoding recombinase A and signal recognition particle protein, respectively, proved to be the most stable set of reference genes under the experimental conditions used. In addition, genes proC and gyrA, encoding pyrroline-5-carboxylate reductase and DNA gyrase, respectively, also displayed relatively stable mRNA expression levels. Conclusion Based on these results, we suggest recA and ffh as suitable candidates for accurate normalisation of real-time RT-PCR data for experiments investigating the plant pathogen P. atrosepticum and potentially other related pathogens. PMID:17888160

  2. How endogenous plant cell-wall degradation mechanisms can help achieve higher efficiency in saccharification of biomass.

    PubMed

    Tavares, Eveline Q P; De Souza, Amanda P; Buckeridge, Marcos S

    2015-07-01

    Cell-wall recalcitrance to hydrolysis still represents one of the major bottlenecks for second-generation bioethanol production. This occurs despite the development of pre-treatments, the prospect of new enzymes, and the production of transgenic plants with less-recalcitrant cell walls. Recalcitrance, which is the intrinsic resistance to breakdown imposed by polymer assembly, is the result of inherent limitations in its three domains. These consist of: (i) porosity, associated with a pectin matrix impairing trafficking through the wall; (ii) the glycomic code, which refers to the fine-structural emergent complexity of cell-wall polymers that are unique to cells, tissues, and species; and (iii) cellulose crystallinity, which refers to the organization in micro- and/or macrofibrils. One way to circumvent recalcitrance could be by following cell-wall hydrolysis strategies underlying plant endogenous mechanisms that are optimized to precisely modify cell walls in planta. Thus, the cell-wall degradation that occurs during fruit ripening, abscission, storage cell-wall mobilization, and aerenchyma formation are reviewed in order to highlight how plants deal with recalcitrance and which are the routes to couple prospective enzymes and cocktail designs with cell-wall features. The manipulation of key enzyme levels in planta can help achieving biologically pre-treated walls (i.e. less recalcitrant) before plants are harvested for bioethanol production. This may be helpful in decreasing the costs associated with producing bioethanol from biomass. PMID:25922489

  3. Gating of the two-pore cation channel AtTPC1 in the plant vacuole is based on a single voltage-sensing domain.

    PubMed

    Jaślan, D; Mueller, T D; Becker, D; Schultz, J; Cuin, T A; Marten, I; Dreyer, I; Schönknecht, G; Hedrich, R

    2016-09-01

    The two-pore cation channel TPC1 operates as a dimeric channel in animal and plant endomembranes. Each subunit consists of two homologous Shaker-like halves, with 12 transmembrane domains in total (S1-S6, S7-S12). In plants, TPC1 channels reside in the vacuolar membrane, and upon voltage stimulation, give rise to the well-known slow-activating SV currents. Here, we combined bioinformatics, structure modelling, site-directed mutagenesis, and in planta patch clamp studies to elucidate the molecular mechanisms of voltage-dependent channel gating in TPC1 in its native plant background. Structure-function analysis of the Arabidopsis TPC1 channel in planta confirmed that helix S10 operates as the major voltage-sensing site, with Glu450 and Glu478 identified as possible ion-pair partners for voltage-sensing Arg537. The contribution of helix S4 to voltage sensing was found to be negligible. Several conserved negative residues on the luminal site contribute to calcium binding, stabilizing the closed channel. During evolution of plant TPC1s from two separate Shaker-like domains, the voltage-sensing function in the N-terminal Shaker-unit (S1-S4) vanished. PMID:27270880

  4. The movement protein of barley yellow dwarf virus-GAV self-interacts and forms homodimers in vitro and in vivo.

    PubMed

    Xia, Zongliang; Cao, Rufei; Sun, Kaile; Zhang, Hua

    2012-07-01

    The 17-kDa movement protein (MP) of the GAV strain of barley yellow dwarf virus (BYDV-GAV) can bind the viral RNA and target to the nucleus. However, much less is known about the active form of the MP in planta. In this study, the ability of the MP to self-interact was analyzed by yeast two-hybrid assay and bimolecular fluorescence complementation. The BYDV-GAV MP has a strong potential to self-interact in vitro and in vivo, and self-interaction was mediated by the N-terminal domain spanning the second α-helix (residues 17-39). Chemical cross-linking and heterologous MP expression from a pea early browning virus (PEBV) vector further showed that MP self-interacts to form homodimers in vitro and in planta. Interestingly, the N-terminal domain necessary for MP self-interaction has previously been identified as important for nuclear targeting. Based on these findings, a functional link between MP self-interaction and nuclear targeting is discussed. PMID:22437255

  5. Impact of rhizosphere factors on cyclic lipopeptide signature from the plant beneficial strain Bacillus amyloliquefaciens S499.

    PubMed

    Nihorimbere, Venant; Cawoy, Hélène; Seyer, Alexandre; Brunelle, Alain; Thonart, Philippe; Ongena, Marc

    2012-01-01

    Cyclic lipopeptides (cLPs) of the surfactin, iturin and fengycin families synthesized by plant-associated Bacilli represent an important class of antibiotics as they may be tightly involved in the protective effect of selected strains against phytopathogens. However, their production by Bacillus cells developing on roots under rhizosphere conditions is still poorly understood. In this work, we combined electrospray and imaging mass spectrometry-based approaches to determine the detailed pattern of surfactins, iturins and fengycins produced in planta by Bacillus amyloliquefaciens S499. Very different production rates were observed for the three cLPs families. Whereas surfactin accumulated in significant amounts, much lower quantities of iturins and fengycins were detected in the environment of colonized roots in comparison with laboratory medium. In addition, the surfactin pattern produced by strain S499 evolving on roots is enriched in homologues with long fatty acid chains (C15) compared with the chains typically secreted under in vitro conditions. Additional experiments revealed that lipopeptide production by root-associated S499 cells is qualitatively and quantitatively dictated by the specific nutritional context of the rhizosphere (exudates enriched in organic acids, oxygen limitation) but also by the formation of biofilm-related structures around root hairs. As surfactins, iturins and fengycins retain specific functions and bioactivities, the biological relevance of their differential production observed in planta is discussed in the context of biocontrol of plant diseases. PMID:22029651

  6. Mitogen-activated protein kinase signal transduction and DNA repair network are involved in aluminum-induced DNA damage and adaptive response in root cells of Allium cepa L.

    PubMed Central

    Panda, Brahma B.; Achary, V. Mohan M.

    2014-01-01

    In the current study, we studied the role of signal transduction in aluminum (Al3+)-induced DNA damage and adaptive response in root cells of Allium cepa L. The root cells in planta were treated with Al3+ (800 μM) for 3 h without or with 2 h pre-treatment of inhibitors of mitogen-activated protein kinase (MAPK), and protein phosphatase. Also, root cells in planta were conditioned with Al3+ (10 μM) for 2 h and then subjected to genotoxic challenge of ethyl methane sulfonate (EMS; 5 mM) for 3 h without or with the pre-treatment of the aforementioned inhibitors as well as the inhibitors of translation, transcription, DNA replication and repair. At the end of treatments, roots cells were assayed for cell death and/or DNA damage. The results revealed that Al3+ (800 μM)-induced significant DNA damage and cell death. On the other hand, conditioning with low dose of Al3+ induced adaptive response conferring protection of root cells from genotoxic stress caused by EMS-challenge. Pre-treatment of roots cells with the chosen inhibitors prior to Al3+-conditioning prevented or reduced the adaptive response to EMS genotoxicity. The results of this study suggested the involvement of MAPK and DNA repair network underlying Al-induced DNA damage and adaptive response to genotoxic stress in root cells of A. cepa. PMID:24926302

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

    PubMed Central

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

    2016-01-01

    Rice bean (Vigna umbellata) VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acid soils where Al stress imposed but Fe deficiency pressure released. PMID:27148333

  8. The Secreted Protease PrtA Controls Cell Growth, Biofilm Formation and Pathogenicity in Xylella fastidiosa

    PubMed Central

    Gouran, Hossein; Gillespie, Hyrum; Nascimento, Rafael; Chakraborty, Sandeep; Zaini, Paulo A.; Jacobson, Aaron; Phinney, Brett S.; Dolan, David; Durbin-Johnson, Blythe P.; Antonova, Elena S.; Lindow, Steven E.; Mellema, Matthew S.; Goulart, Luiz R.; Dandekar, Abhaya M.

    2016-01-01

    Pierce’s disease (PD) is a deadly disease of grapevines caused by the Gram-negative bacterium Xylella fastidiosa. Though disease symptoms were formerly attributed to bacteria blocking the plant xylem, this hypothesis is at best overly simplistic. Recently, we used a proteomic approach to characterize the secretome of X. fastidiosa, both in vitro and in planta, and identified LesA as one of the pathogenicity factors of X. fastidiosa in grapevines that leads to leaf scorching and chlorosis. Herein, we characterize another such factor encoded by PD0956, designated as an antivirulence secreted protease “PrtA” that displays a central role in controlling in vitro cell proliferation, length, motility, biofilm formation, and in planta virulence. The mutant in X. fastidiosa exhibited reduced cell length, hypermotility (and subsequent lack of biofilm formation) and hypervirulence in grapevines. These findings are supported by transcriptomic and proteomic analyses with corresponding plant infection data. Of particular interest, is the hypervirulent response in grapevines observed when X. fastidiosa is disrupted for production of PrtA, and that PD-model tobacco plants transformed to express PrtA exhibited decreased symptoms after infection by X. fastidiosa. PMID:27492542

  9. The Secreted Protease PrtA Controls Cell Growth, Biofilm Formation and Pathogenicity in Xylella fastidiosa.

    PubMed

    Gouran, Hossein; Gillespie, Hyrum; Nascimento, Rafael; Chakraborty, Sandeep; Zaini, Paulo A; Jacobson, Aaron; Phinney, Brett S; Dolan, David; Durbin-Johnson, Blythe P; Antonova, Elena S; Lindow, Steven E; Mellema, Matthew S; Goulart, Luiz R; Dandekar, Abhaya M

    2016-01-01

    Pierce's disease (PD) is a deadly disease of grapevines caused by the Gram-negative bacterium Xylella fastidiosa. Though disease symptoms were formerly attributed to bacteria blocking the plant xylem, this hypothesis is at best overly simplistic. Recently, we used a proteomic approach to characterize the secretome of X. fastidiosa, both in vitro and in planta, and identified LesA as one of the pathogenicity factors of X. fastidiosa in grapevines that leads to leaf scorching and chlorosis. Herein, we characterize another such factor encoded by PD0956, designated as an antivirulence secreted protease "PrtA" that displays a central role in controlling in vitro cell proliferation, length, motility, biofilm formation, and in planta virulence. The mutant in X. fastidiosa exhibited reduced cell length, hypermotility (and subsequent lack of biofilm formation) and hypervirulence in grapevines. These findings are supported by transcriptomic and proteomic analyses with corresponding plant infection data. Of particular interest, is the hypervirulent response in grapevines observed when X. fastidiosa is disrupted for production of PrtA, and that PD-model tobacco plants transformed to express PrtA exhibited decreased symptoms after infection by X. fastidiosa. PMID:27492542

  10. Mitogen-Activated Protein Kinase Cascade MKK7-MPK6 Plays Important Roles in Plant Development and Regulates Shoot Branching by Phosphorylating PIN1 in Arabidopsis.

    PubMed

    Jia, Weiyan; Li, Baohua; Li, Shujia; Liang, Yan; Wu, Xiaowei; Ma, Mei; Wang, Jiyao; Gao, Jin; Cai, Yueyue; Zhang, Yuanya; Wang, Yingchun; Li, Jiayang; Wang, Yonghong

    2016-09-01

    Emerging evidences exhibit that mitogen-activated protein kinase (MAPK/MPK) signaling pathways are connected with many aspects of plant development. The complexity of MAPK cascades raises challenges not only to identify the MAPK module in planta but also to define the specific role of an individual module. So far, our knowledge of MAPK signaling has been largely restricted to a small subset of MAPK cascades. Our previous study has characterized an Arabidopsis bushy and dwarf1 (bud1) mutant, in which the MAP Kinase Kinase 7 (MKK7) was constitutively activated, resulting in multiple phenotypic alterations. In this study, we found that MPK3 and MPK6 are the substrates for phosphorylation by MKK7 in planta. Genetic analysis showed that MKK7-MPK6 cascade is specifically responsible for the regulation of shoot branching, hypocotyl gravitropism, filament elongation, and lateral root formation, while MKK7-MPK3 cascade is mainly involved in leaf morphology. We further demonstrated that the MKK7-MPK6 cascade controls shoot branching by phosphorylating Ser 337 on PIN1, which affects the basal localization of PIN1 in xylem parenchyma cells and polar auxin transport in the primary stem. Our results not only specify the functions of the MKK7-MPK6 cascade but also reveal a novel mechanism for PIN1 phosphorylation, establishing a molecular link between the MAPK cascade and auxin-regulated plant development. PMID:27618482

  11. Pseudomonas syringae Catalases Are Collectively Required for Plant Pathogenesis

    PubMed Central

    Guo, Ming; Block, Anna; Bryan, Crystal D.; Becker, Donald F.

    2012-01-01

    The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 must detoxify plant-produced hydrogen peroxide (H2O2) in order to survive in its host plant. Candidate enzymes for this detoxification include the monofunctional catalases KatB and KatE and the bifunctional catalase-peroxidase KatG of DC3000. This study shows that KatG is the major housekeeping catalase of DC3000 and provides protection against menadione-generated endogenous H2O2. In contrast, KatB rapidly and substantially accumulates in response to exogenous H2O2. Furthermore, KatB and KatG have nonredundant roles in detoxifying exogenous H2O2 and are required for full virulence of DC3000 in Arabidopsis thaliana. Therefore, the nonredundant ability of KatB and KatG to detoxify plant-produced H2O2 is essential for the bacteria to survive in plants. Indeed, a DC3000 catalase triple mutant is severely compromised in its ability to grow in planta, and its growth can be partially rescued by the expression of katB, katE, or katG. Interestingly, our data demonstrate that although KatB and KatG are the major catalases involved in the virulence of DC3000, KatE can also provide some protection in planta. Thus, our results indicate that these catalases are virulence factors for DC3000 and are collectively required for pathogenesis. PMID:22797762

  12. A Phytophthora infestans RXLR effector targets plant PP1c isoforms that promote late blight disease.

    PubMed

    Boevink, Petra C; Wang, Xiaodan; McLellan, Hazel; He, Qin; Naqvi, Shaista; Armstrong, Miles R; Zhang, Wei; Hein, Ingo; Gilroy, Eleanor M; Tian, Zhendong; Birch, Paul R J

    2016-01-01

    Plant pathogens deliver effectors to alter host processes. Knowledge of how effectors target and manipulate host proteins is critical to understand crop disease. Here, we show that in planta expression of the RXLR effector Pi04314 enhances leaf colonization by Phytophthora infestans via activity in the host nucleus and attenuates induction of jasmonic and salicylic acid-responsive genes. Pi04314 interacts with three host protein phosphatase 1 catalytic (PP1c) isoforms, causing their re-localization from the nucleolus to the nucleoplasm. Re-localization of PP1c-1 also occurs during infection and is dependent on an R/KVxF motif in the effector. Silencing the PP1c isoforms or overexpression of a phosphatase-dead PP1c-1 mutant attenuates infection, demonstrating that host PP1c activity is required for disease. Moreover, expression of PP1c-1mut abolishes enhanced leaf colonization mediated by in planta Pi04314 expression. We argue that PP1c isoforms are susceptibility factors forming holoenzymes with Pi04314 to promote late blight disease. PMID:26822079

  13. Mutations in the NB-ARC Domain of I-2 That Impair ATP Hydrolysis Cause Autoactivation1[OA

    PubMed Central

    Tameling, Wladimir I.L.; Vossen, Jack H.; Albrecht, Mario; Lengauer, Thomas; Berden, Jan A.; Haring, Michel A.; Cornelissen, Ben J.C.; Takken, Frank L.W.

    2006-01-01

    Resistance (R) proteins in plants confer specificity to the innate immune system. Most R proteins have a centrally located NB-ARC (nucleotide-binding adaptor shared by APAF-1, R proteins, and CED-4) domain. For two tomato (Lycopersicon esculentum) R proteins, I-2 and Mi-1, we have previously shown that this domain acts as an ATPase module that can hydrolyze ATP in vitro. To investigate the role of nucleotide binding and hydrolysis for the function of I-2 in planta, specific mutations were introduced in conserved motifs of the NB-ARC domain. Two mutations resulted in autoactivating proteins that induce a pathogen-independent hypersensitive response upon expression in planta. These mutant forms of I-2 were found to be impaired in ATP hydrolysis, but not in ATP binding, suggesting that the ATP- rather than the ADP-bound state of I-2 is the active form that triggers defense signaling. In addition, upon ADP binding, the protein displayed an increased affinity for ADP suggestive of a change of conformation. Based on these data, we propose that the NB-ARC domain of I-2, and likely of related R proteins, functions as a molecular switch whose state (on/off) depends on the nucleotide bound (ATP/ADP). PMID:16489136

  14. RNAi Suppression of Arogenate Dehydratase1 Reveals That Phenylalanine Is Synthesized Predominantly via the Arogenate Pathway in Petunia Petals[C][W

    PubMed Central

    Maeda, Hiroshi; Shasany, Ajit K; Schnepp, Jennifer; Orlova, Irina; Taguchi, Goro; Cooper, Bruce R.; Rhodes, David; Pichersky, Eran; Dudareva, Natalia

    2010-01-01

    l-Phe, a protein building block and precursor of numerous phenolic compounds, is synthesized from prephenate via an arogenate and/or phenylpyruvate route in which arogenate dehydratase (ADT) or prephenate dehydratase, respectively, plays a key role. Here, we used Petunia hybrida flowers, which are rich in Phe-derived volatiles, to determine the biosynthetic routes involved in Phe formation in planta. Of the three identified petunia ADTs, expression of ADT1 was the highest in petunia petals and positively correlated with endogenous Phe levels throughout flower development. ADT1 showed strict substrate specificity toward arogenate, although with the lowest catalytic efficiency among the three ADTs. ADT1 suppression via RNA interference in petunia petals significantly reduced ADT activity, levels of Phe, and downstream phenylpropanoid/benzenoid volatiles. Unexpectedly, arogenate levels were unaltered, while shikimate and Trp levels were decreased in transgenic petals. Stable isotope labeling experiments showed that ADT1 suppression led to downregulation of carbon flux toward shikimic acid. However, an exogenous supply of shikimate bypassed this negative regulation and resulted in elevated arogenate accumulation. Feeding with shikimate also led to prephenate and phenylpyruvate accumulation and a partial recovery of the reduced Phe level in transgenic petals, suggesting that the phenylpyruvate route can also operate in planta. These results provide genetic evidence that Phe is synthesized predominantly via arogenate in petunia petals and uncover a novel posttranscriptional regulation of the shikimate pathway. PMID:20215586

  15. Alcohol oxidase is a novel pathogenicity factor for Cladosporium fulvum, but aldehyde dehydrogenase is dispensable.

    PubMed

    Segers, G; Bradshaw, N; Archer, D; Blissett, K; Oliver, R P

    2001-03-01

    Cladosporiumfulvum is a mitosporic ascomycete pathogen of tomato. A study of fungal genes expressed during carbon starvation in vitro identified several genes that were up regulated during growth in planta. These included genes predicted to encode acetaldehyde dehydrogenase (Aldh1) and alcohol oxidase (Aox1). An Aldh1 deletion mutant was constructed. This mutant lacked all detectable ALDH activity, had lost the ability to grow with ethanol as a carbon source, but was unaffected in pathogenicity. Aox1 expression was induced by carbon starvation and during the later stages of infection. The alcohol oxidase enzyme activity has broadly similar properties (Km values, substrate specificity, pH, and heat stability) to yeast enzymes. Antibodies raised to Hansenula polymorpha alcohol oxidase (AOX) detected antigens in Western blots of starved C. fulvum mycelium and infected plant material. Antigen reacting with the antibodies was localized to organelles resembling peroxisomes in starved mycelium and infected plants. Disruption mutants of Aox1 lacked detectable AOX activity and had markedly reduced pathogenicity as assayed by two different measures of fungal growth. These results identify alcohol oxidase as a novel pathogenicity factor and are discussed in relation to peroxisomal metabolism of fungal pathogens during growth in planta. PMID:11277434

  16. Contribution of mangotoxin to the virulence and epiphytic fitness of Pseudomonas syringae pv. syringae.

    PubMed

    Arrebola, Eva; Cazorla, Francisco M; Codina, Juan C; Gutiérrez-Barranquero, José A; Pérez-García, Alejandro; de Vicente, Antonio

    2009-06-01

    Mangotoxin is an antimetabolite toxin that inhibits ornithine acetyl transferase, a key enzyme in the biosynthetic pathway of ornithine and arginine and recently reported in strains of Pseudomonas syringae pv. syringae (Pss) isolated from mango. Since symptoms on mango tissues are very difficult to reproduce, in this study the role of mangotoxin in Pss virulence was addressed by analyzing the in planta growth and development of disease symptoms on tomato leaflets. Inoculation experiments were carried out following several procedures using the wild-type strain Pss UMAF0158, two Tn5-mutant derivative strains defective in mangotoxin production, and their complemented derivative strains in which mangotoxin production is restored. The ability of the mangotoxin-defective mutants to grow in planta was similar, and their epiphytic survival on the tomato leaf surface identical to the wild-type and complemented strains. However, both the disease index data of incidence and the severity of necrotic symptoms indicated that mangotoxin-defective mutants were less virulent, indicating that mangotoxin is a virulence factor. Furthermore, competition experiments showed that the survival values of the wild-type strain were slightly but significantly higher than those of the mangotoxin-defective mutants, suggesting that mangotoxin production would improve the epiphytic fitness of Pss. PMID:19784928

  17. Root Uptake of Pharmaceuticals and Personal Care Product Ingredients.

    PubMed

    Miller, Elizabeth L; Nason, Sara L; Karthikeyan, K G; Pedersen, Joel A

    2016-01-19

    Crops irrigated with reclaimed wastewater or grown in biosolids-amended soils may take up pharmaceuticals and personal care product ingredients (PPCPs) through their roots. The uptake pathways followed by PPCPs and the propensity for these compounds to bioaccumulate in food crops are still not well understood. In this critical review, we discuss processes expected to influence root uptake of PPCPs, evaluate current literature on uptake of PPCPs, assess models for predicting plant uptake of these compounds, and provide recommendations for future research, highlighting processes warranting study that hold promise for improving mechanistic understanding of plant uptake of PPCPs. We find that many processes that are expected to influence PPCP uptake and accumulation have received little study, particularly rhizosphere interactions, in planta transformations, and physicochemical properties beyond lipophilicity (as measured by Kow). Data gaps and discrepancies in methodology and reporting have so far hindered development of models that accurately predict plant uptake of PPCPs. Topics warranting investigation in future research include the influence of rhizosphere processes on uptake, determining mechanisms of uptake and accumulation, in planta transformations, the effects of PPCPs on plants, and the development of predictive models. PMID:26619126

  18. Precursor feeding studies and molecular characterization of geraniol synthase establish the limiting role of geraniol in monoterpene indole alkaloid biosynthesis in Catharanthus roseus leaves.

    PubMed

    Kumar, Krishna; Kumar, Sarma Rajeev; Dwivedi, Varun; Rai, Avanish; Shukla, Ashutosh K; Shanker, Karuna; Nagegowda, Dinesh A

    2015-10-01

    The monoterpene indole alkaloids (MIAs) are generally derived from strictosidine, which is formed by condensation of the terpene moiety secologanin and the indole moiety tryptamine. There are conflicting reports on the limitation of either terpene or indole moiety in the production of MIAs in Catharanthus roseus cell cultures. Formation of geraniol by geraniol synthase (GES) is the first step in secologanin biosynthesis. In this study, feeding of C. roseus leaves with geraniol, but not tryptophan (precursor for tryptamine), increased the accumulation of the MIAs catharanthine and vindoline, indicating the limitation of geraniol in MIA biosynthesis. This was further validated by molecular and in planta characterization of C. roseus GES (CrGES). CrGES transcripts exhibited leaf and shoot specific expression and were induced by methyl jasmonate. Virus-induced gene silencing (VIGS) of CrGES significantly reduced the MIA content, which was restored to near-WT levels upon geraniol feeding. Moreover, over-expression of CrGES in C. roseus leaves increased MIA content. Further, CrGES exhibited correlation with MIA levels in leaves of different C. roseus cultivars and has significantly lower expression relative to other pathway genes. These results demonstrated that the transcriptional regulation of CrGES and thus, the in planta geraniol availability plays crucial role in MIA biosynthesis. PMID:26398791

  19. Extracellular peptidases of the cereal pathogen Fusarium graminearum

    PubMed Central

    Lowe, Rohan G. T.; McCorkelle, Owen; Bleackley, Mark; Collins, Christine; Faou, Pierre; Mathivanan, Suresh; Anderson, Marilyn

    2015-01-01

    The plant pathogenic fungus Fusarium graminearum (Fgr) creates economic and health risks in cereals agriculture. Fgr causes head blight (or scab) of wheat and stalk rot of corn, reducing yield, degrading grain quality, and polluting downstream food products with mycotoxins. Fungal plant pathogens must secrete proteases to access nutrition and to breakdown the structural protein component of the plant cell wall. Research into the proteolytic activity of Fgr is hindered by the complex nature of the suite of proteases secreted. We used a systems biology approach comprising genome analysis, transcriptomics and label-free quantitative proteomics to characterize the peptidases deployed by Fgr during growth. A combined analysis of published microarray transcriptome datasets revealed seven transcriptional groupings of peptidases based on in vitro growth, in planta growth, and sporulation behaviors. A high resolution mass spectrometry-based proteomics analysis defined the extracellular proteases secreted by F. graminearum. A meta-classification based on sequence characters and transcriptional/translational activity in planta and in vitro provides a platform to develop control strategies that target Fgr peptidases. PMID:26635820

  20. The Azorhizobium caulinodans nifA gene: identification of upstream-activating sequences including a new element, the 'anaerobox'.

    PubMed Central

    Nees, D W; Stein, P A; Ludwig, R A

    1988-01-01

    From nucleotide sequencing analyses, the A. caulinodans nifA gene seems to be under dual control by the Ntr (in response to available N) and Fnr (in response to available O2) transcriptional activation/repression systems. Because it fixes N2 in two contexts, the Ntr system might regulate A. caulinodans nif gene expression ex planta, while the Fnr system might similarly regulate in planta. As nifA upstream-activating elements, we have identified: (i) a gpNifA binding site allowing autogenous nifA regulation, (ii) an Ntr-dependent transcription start, presumably the target of gpNifA activation, and (iii) an "anaerobox" tetradecameric nucleotide sequence that is precisely conserved among O2 regulated enteric bacterial genes controlled by the gpFnr transcriptional activator. Because it is precisely positioned upstream of enteric bacterial transcriptional starts, the "anaerobox" sequence may constitute the gpFnr DNA binding site. If so, then a second, Ntr-independent nifA transcription start may exist. We have also deduced the A. caulinodans nifA open reading frame and have compared the gene product (gpNifA) with those of other N2-fixing organisms. These proteins exhibit strongly conserved motifs: (i) sites conserved among ATP-binding proteins, (ii) an interdomain linker region, and (iii) a C-terminal alpha-helix-turn-alpha-helix DNA binding site. PMID:3186446

  1. Camelid nanobodies with high affinity for broad bean mottle virus: a possible promising tool to immunomodulate plant resistance against viruses.

    PubMed

    Ghannam, Ahmed; Kumari, Safa; Muyldermans, Serge; Abbady, Abdul Qader

    2015-03-01

    Worldwide, plant viral infections decrease seriously the crop production yield, boosting the demand to develop new strategies to control viral diseases. One of these strategies to prevent viral infections, based on the immunomodulation faces many problems related to the ectopic expression of specific antibodies in planta. Camelid nanobodies, expressed in plants, may offer a solution as they are an attractive tool to bind efficiently to viral epitopes, cryptic or not accessible to conventional antibodies. Here, we report a novel, generic approach that might lead to virus resistance based on the expression of camelid specific nanobodies against Broad bean mottle virus (BBMV). Eight nanobodies, recognizing BBMV with high specificity and affinity, were retrieved after phage display from a large 'immune' library constructed from an immunized Arabic camel. By an in vitro assay we demonstrate how three nanobodies attenuate the BBMV spreading in inoculated Vicia faba plants. Furthermore, the in planta transient expression of these three selected nanobodies confirms their virus neutralizing capacity. In conclusion, this report supports that plant resistance against viral infections can be achieved by the in vivo expression of camelid nanobodies. PMID:25648551

  2. Characterization of Coffee ringspot virus-Lavras: A model for an emerging threat to coffee production and quality

    SciTech Connect

    Ramalho, T.O.; Figueira, A.R.; Sotero, A.J.; Wang, R.; Geraldino Duarte, P.S.; Farman, M.; Goodin, M.M.

    2014-09-15

    The emergence of viruses in Coffee (Coffea arabica and Coffea canephora), the most widely traded agricultural commodity in the world, is of critical concern. The RNA1 (6552 nt) of Coffee ringspot virus is organized into five open reading frames (ORFs) capable of encoding the viral nucleocapsid (ORF1p), phosphoprotein (ORF2p), putative cell-to-cell movement protein (ORF3p), matrix protein (ORF4p) and glycoprotein (ORF5p). Each ORF is separated by a conserved intergenic junction. RNA2 (5945 nt), which completes the bipartite genome, encodes a single protein (ORF6p) with homology to RNA-dependent RNA polymerases. Phylogenetic analysis of L protein sequences firmly establishes CoRSV as a member of the recently proposed Dichorhavirus genus. Predictive algorithms, in planta protein expression, and a yeast-based nuclear import assay were used to determine the nucleophillic character of five CoRSV proteins. Finally, the temperature-dependent ability of CoRSV to establish systemic infections in an initially local lesion host was quantified. - Highlights: • We report genome sequence determination for Coffee ringspot virus (CoRSV). • CoRSV should be considered a member of the proposed Dichorhavirus genus. • We report temperature-dependent systemic infection of an initially local lesion host. • We report in planta protein and localization data for five CoRSV proteins. • In silico predictions of the CoRSV proteins were validated using in vivo assays.

  3. A quantitative synthesis of the medicinal ethnobotany of the Malinké of Mali and the Asháninka of Peru, with a new theoretical framework

    PubMed Central

    Bletter, Nathaniel

    2007-01-01

    from around the world to pinpoint the species with the highest potential efficacy to take into the laboratory and analyze further, ultimately saving much field and laboratory time and resources. Spanish abstract Las búsquedas que utilizan la etnomedicina y la taxonomía para descubrir nuevas plantas medicinales, pueden aumentar la probabilidad de éxito de encontrar compuestos químicos activos en plantas, en comparación con las búsquedas aleatorias. A pesar de lo anterior, en las últimas décadas, la etnobotánica no ha cumplido con las expectativas de proveer numerosas plantas medicinales y químicos nuevos una vez examinados en el laboratorio. Cada año se describen una plétora de plantas medicinales y sus usos, sin embargo las limitaciones de tiempo y recursos en los laboratorios, unidos al alto coste de los ensayos clínicos de las drogas potenciales, hacen muy difícil probar, aislar, y elucidar la estructura y el mecanismo de los compuestos de estas plantas. Se propone un nuevo marco teórico cuantitativo cuyo fin es focalizar la búsqueda de nueva plantas medicinales. Este marco teórico está basado en la hipótesis que las plantas cercanamente relacionadas, usadas para tratar enfermedades cercanamente relacionadas en culturas distantemente relacionadas, tienen una eficacia potencial más alta, debido a que es más probable que estos hallazgos sean descubrimientos independientes de compuestos químicos similares. Parte de esta hipótesis, que las escogencias racionales se hacen para elegir plantas medicinales similares y que la flora medicinal de dos culturas distantes es más similar que su flora general, se probó usando métodos estadísticos de remuestreo con datos de campo de la comunidad Malinké de Malí y de la Asháninka de Perú, y las enfermedades de paludismo, enfermedad africana del sueño, enfermedad de Chagas, leishmania, diabetes, eczema, asma, y fibromas uterinos. Se encontró, en este caso, que

  4. Iron acquisition from Fe-pyoverdine by Arabidopsis thaliana.

    PubMed

    Vansuyt, Gérard; Robin, Agnès; Briat, Jean-François; Curie, Catherine; Lemanceau, Philippe

    2007-04-01

    Taking into account the strong iron competition in the rhizosphere and the high affinity of pyoverdines for Fe(III), these molecules are expected to interfere with the iron nutrition of plants, as they do with rhizospheric microbes. The impact of Fe-pyoverdine on iron content of Arabidopsis thaliana was compared with that of Fe-EDTA. Iron chelated to pyoverdine was incorporated in a more efficient way than when chelated to EDTA, leading to increased plant growth of the wild type. A transgenic line of A. thaliana overexpressing ferritin showed a higher iron content than the wild type when supplemented with Fe-EDTA but a lower iron content when supplemented with Fe-pyoverdine despite its increased reductase activity, suggesting that this activity was not involved in the iron uptake from pyoverdine. A mutant knock-out iron transporter IRT1 showed lower iron and chlorophyll contents when supplemented with Fe-EDTA than the wild type but not when supplemented with Fe-pyoverdine, indicating that, in contrast to iron from EDTA, iron from pyoverdine was not incorporated through the IRT1 transporter. Altogether these data suggest that iron from Fe-pyoverdine was not incorporated in planta through the strategy I, which is based on reductase activity and IRT1 transporter. This is supported by the presence of pyoverdine in planta as shown by enzyme-linked immunosorbent assay and by tracing 15N of 15N-pyoverdine. PMID:17427814

  5. Holophytochrome-Interacting Proteins in Physcomitrella: Putative Actors in Phytochrome Cytoplasmic Signaling

    PubMed Central

    Ermert, Anna Lena; Mailliet, Katharina; Hughes, Jon

    2016-01-01

    Phytochromes are the principle photoreceptors in light-regulated plant development, primarily acting via translocation of the light-activated photoreceptor into the nucleus and subsequent gene regulation. However, several independent lines of evidence indicate unambiguously that an additional cytoplasmic signaling mechanism must exist. Directional responses in filament tip cells of the moss Physcomitrella patens are steered by phy4 which has been shown to interact physically with the blue light receptor phototropin at the plasma membrane. This complex might perceive and transduce vectorial information leading to cytoskeleton reorganization and finally a directional growth response. We developed yeast two-hybrid procedures using photochemically functional, full-length phy4 as bait in Physcomitrella cDNA library screens and growth assays under different light conditions, revealing Pfr-dependent interactions possibly associated with phytochrome cytoplasmic signaling. Candidate proteins were then expressed in planta with fluorescent protein tags to determine their intracellular localization in darkness and red light. Of 14 candidates, 12 were confirmed to interact with phy4 in planta using bimolecular fluorescence complementation. We also used database information to study their expression patterns relative to those of phy4. We discuss the likely functional characteristics of these holophytochrome-interacting proteins (HIP’s) and their possible roles in signaling. PMID:27242820

  6. Histochemical and immunohistochemical identification of laticifer cells in callus cultures derived from anthers of Hevea brasiliensis.

    PubMed

    Tan, Deguan; Sun, Xuepiao; Zhang, Jiaming

    2011-06-01

    Laticifers are highly specialized cells present in over 20 plant families. They are well defined in planta. In vitro development of laticifers was also observed in some plants, but uncertain in the callus cultures of rubber tree, one of the most economically important latex producing plants. In the present study, we provide evidence that laticifer cells present in the callus cultures of rubber tree by histochemical and immunohistochemical studies. They present in the callus mainly as separate non-elongated form, a novel morphology different from the morphology of laticifer cells in planta, excluding their origin from explants. The occurring frequency of laticifer cells in the callus was genotype-dependent and negatively correlated with the somatic embryogenetic ability, suggesting that the presence of laticifer cells in the callus inhibit somatic embryogenesis in tissue culture of rubber tree. The genotypes PR107, RRIM600, Reyan8-79, and Reyan7-33-97 with lower embryogenetic ability compared to Haiken 2 had more laticifer cells, and laticifer clusters were only observed in these genotypes. PMID:21301851

  7. Application of RNA interference methodology to investigate and develop SCMV resistance in maize.

    PubMed

    Gan, Defang; Ding, Fei; Zhuang, Dan; Jiang, Haiyang; Jiang, Tong; Zhu, Suwen; Cheng, Beijiu

    2014-08-01

    Specific fragments of the sugarcane mosaic virus (SCMV) coat protein gene (cp) were amplified by reverse transcriptionpolymerase chain reaction and used to construct a marker free small interfering RNA complex expression vector against SCMV. In planta transformation was performed on maize (Zea mays) inbred line 8112 mediated by Agrobacterium tumefaciens. PCR and Southern blot analyses demonstrated successful integration of the cp segment into the 8112 genome. The in planta transformation frequency was 0.1%, and the cotransformed frequency with the cp and bar genes was 0.034%. Real-time quantitative PCR of samples from different transgenic plant organs showed that the expression of the cp gene fragment in transgenic plants was variable and that the highest expression level occurred in the tassels and leaves and the lowest expression occurred in the roots. Real-time quantitative PCR was also used to measure how gene expression in transgenic T2 generation plants inoculated with SCMV changes over time. The results showed that the hairpin RNA structure transcribed from the cp gene interfered with SCMV infection and transgenic maize lines were not equally effective in preventing SCMV infection. Our findings provide a valuable tool for controlling plant viruses using RNA interference and the posttranslational gene silencing approach. PMID:25189224

  8. Stability of the delta-endotoxin gene from Bacillus thuringiensis subsp. kurstaki in a recombinant strain of Clavibacter xyli subsp. cynodontis.

    PubMed Central

    Turner, J T; Lampel, J S; Stearman, R S; Sundin, G W; Gunyuzlu, P; Anderson, J J

    1991-01-01

    Deletion of chromosomally inserted gene sequences from Clavibacter xyli subsp. cynodontis, a xylem-inhabiting endophyte, was studied in vitro and in planta. We found that nonreplicating plasmid pCG610, which conferred resistance to kanamycin and tetracycline and contained segments of C. xyli subsp. cynodontis genomic DNA, integrated into a homologous sequence in the bacterial chromosome. In addition, pCG610 contains two copies of the gene encoding the CryIA(c) insecticidal protein of Bacillus thuringiensis subsp. kurstaki HD73. Using drug resistance phenotypes and specific DNA probes, we found that the loss of all three genes arose both in vitro under nonselective conditions and in planta. The resulting segregants are probably formed by recombination between the repeated DNA sequences flanking pCG610 that resulted from the integration event into the chromosome. Eventually, segregants predominated in the bacterial population. The loss of the integrated plasmid from C. xyli subsp. cynodontis revealed a possible approach for decreasing the environmental consequences of recombinant bacteria for agricultural use. Images PMID:1664710

  9. Inhibition of Phytophthora parasitica and P. capsici by Silver Nanoparticles Synthesized Using Aqueous Extract of Artemisia absinthium.

    PubMed

    Ali, Mohammad; Kim, Bosung; Belfield, Kevin D; Norman, David; Brennan, Mary; Ali, Gul Shad

    2015-09-01

    Application of nanoparticles for controlling plant pathogens is a rapidly emerging area in plant disease management, and nanoparticles synthesis methods that are economical and ecofriendly are extensively investigated. In this project, we investigated the potential of silver nanoparticles (AgNPs) synthesized with aqueous extract of Artemisia absinthium against several Phytophthora spp., which cause many economically important crop diseases. In in vitro dose-response tests conducted in microtiter plates, 10 µg ml⁻¹ of AgNPs inhibited mycelial growth of P. parasitica, P. infestans, P. palmivora, P. cinnamomi, P. tropicalis, P. capsici, and P. katsurae. Detailed in vitro dose-response analyses conducted with P. parasitica and P. capsici revealed that AgNPs synthesized with A. absinthium extract were highly potent (IC50: 2.1 to 8.3 µg ml⁻¹) and efficacious (100%) in inhibiting mycelial growth, zoospore germination, germ tube elongation, and zoospore production. Interestingly, AgNP treatment accelerated encystment of zoospores. Consistent with in vitro results, in planta experiments conducted in a greenhouse revealed that AgNP treatments prevented Phytophthora infection and improved plant survival. Moreover, AgNP in in planta experiments did not produce any adverse effects on plant growth. These investigations provide a simple and economical method for controlling Phytophthora with AgNP without affecting normal plant physiology. PMID:25871856

  10. The Multifunctional β-Oxidation Enzyme Is Required for Full Symptom Development by the Biotrophic Maize Pathogen Ustilago maydis▿

    PubMed Central

    Klose, Jana; Kronstad, James W.

    2006-01-01

    The transition from yeast-like to filamentous growth in the biotrophic fungal phytopathogen Ustilago maydis is a crucial event for pathogenesis. Previously, we showed that fatty acids induce filamentation in U. maydis and that the resulting hyphal cells resemble the infectious filaments observed in planta. To explore the potential metabolic role of lipids in the morphological transition and in pathogenic development in host tissue, we deleted the mfe2 gene encoding the multifunctional enzyme that catalyzes the second and third reactions in β-oxidation of fatty acids in peroxisomes. The growth of the strains defective in mfe2 was attenuated on long-chain fatty acids and abolished on very-long-chain fatty acids. The mfe2 gene was not generally required for the production of filaments during mating in vitro, but loss of the gene blocked extensive proliferation of fungal filaments in planta. Consistent with this observation, mfe2 mutants exhibited significantly reduced virulence in that only 27% of infected seedlings produced tumors compared to 88% tumor production upon infection by wild-type strains. Similarly, a defect in virulence was observed in developing ears upon infection of mature maize plants. Specifically, the absence of the mfe2 gene delayed the development of teliospores within mature tumor tissue. Overall, these results indicate that the ability to utilize host lipids contributes to the pathogenic development of U. maydis. PMID:16998075

  11. Functional Characterization and Substrate Promiscuity of UGT71 Glycosyltransferases from Strawberry (Fragaria × ananassa).

    PubMed

    Song, Chuankui; Gu, Le; Liu, Jingyi; Zhao, Shuai; Hong, Xiaotong; Schulenburg, Katja; Schwab, Wilfried

    2015-12-01

    Glycosylation determines the complexity and diversity of plant natural products. To characterize fruit ripening-related UDP-dependent glycosyltransferases (UGTs) functionally in strawberry, we mined the publicly available Fragaria vesca genome sequence and found 199 putative UGT genes. Candidate UGTs whose expression levels were strongly up-regulated during fruit ripening were cloned from F.×ananassa and six were successfully expressed in Escherichia coli and biochemically characterized. UGT75T1 showed very strict substrate specificity and glucosylated only galangin out of 33 compounds. The other recombinant enzymes exhibited broad substrate tolerance, accepting numerous flavonoids, hydroxycoumarins, naphthols and the plant hormone, (+)-S-abscisic acid (ABA). UGT71W2 showed the highest activity towards 1-naphthol, while UGT71A33, UGT71A34a/b and UGT71A35 preferred 3-hydroxycoumarin and formed 3- and 7-O-glucosides as well as a diglucoside from flavonols. Screening of a strawberry physiological aglycone library identified kaempferol, quercetin, ABA and three unknown natural compounds as putative in planta substrates of UGT71A33, UGT71A34a and UGT71W2. Metabolite analyses of RNA interference (RNAi)-mediated silenced fruits demonstrated that UGT71W2 contributes to the glycosylation of flavonols, xenobiotics and, to a minor extent, of ABA, in planta. The study showed that both specialist and generalist UGTs were expressed during strawberry fruit ripening and the latter were probably not restricted to only one function in plants. PMID:26454881

  12. Externally imposed electric field enhances plant root tip regeneration.

    PubMed

    Kral, Nicolas; Hanna Ougolnikova, Alexandra; Sena, Giovanni

    2016-06-01

    In plants, shoot and root regeneration can be induced in the distinctive conditions of tissue culture (in vitro) but is also observed in intact individuals (in planta) recovering from tissue damage. Roots, for example, can regenerate their fully excised meristems in planta, even in mutants with impaired apical stem cell niches. Unfortunately, to date a comprehensive understanding of regeneration in plants is still missing. Here, we provide evidence that an imposed electric field can perturb apical root regeneration in Arabidopsis. Crucially, we explored both spatial and temporal competences of the stump to respond to electrical stimulation, by varying respectively the position of the cut and the time interval between excision and stimulation. Our data indicate that a brief pulse of an electric field parallel to the root is sufficient to increase by up to two-fold the probability of its regeneration, and to perturb the local distribution of the hormone auxin, as well as cell division regulation. Remarkably, the orientation of the root towards the anode or the cathode is shown to play a role. PMID:27606066

  13. The C-Glycosylation of Flavonoids in Cereals*♦

    PubMed Central

    Brazier-Hicks, Melissa; Evans, Kathryn M.; Gershater, Markus C.; Puschmann, Horst; Steel, Patrick G.; Edwards, Robert

    2009-01-01

    Flavonoids normally accumulate in plants as O-glycosylated derivatives, but several species, including major cereal crops, predominantly synthesize flavone-C-glycosides, which are stable to hydrolysis and are biologically active both in planta and as dietary components. An enzyme (OsCGT) catalyzing the UDP-glucose-dependent C-glucosylation of 2-hydroxyflavanone precursors of flavonoids has been identified and cloned from rice (Oryza sativa ssp. indica), with a similar protein characterized in wheat (Triticum aestivum L.). OsCGT is a 49-kDa family 1 glycosyltransferase related to known O-glucosyltransferases. The recombinant enzyme C-glucosylated 2-hydroxyflavanones but had negligible O-glucosyltransferase activity with flavonoid acceptors. Enzyme chemistry studies suggested that OsCGT preferentially C-glucosylated the dibenzoylmethane tautomers formed in equilibrium with 2-hydroxyflavanones. The resulting 2-hydroxyflavanone-C-glucosides were unstable and spontaneously dehydrated in vitro to yield a mixture of 6C- and 8C-glucosyl derivatives of the respective flavones. In contrast, in planta, only the respective 6C-glucosides accumulated. Consistent with this selectivity in glycosylation product, a dehydratase activity that preferentially converted 2-hydroxyflavanone-C-glucosides to the corresponding flavone-6C-glucosides was identified in both rice and wheat. Our results demonstrate that cereal crops synthesize C-glucosylated flavones through the concerted action of a CGT and dehydratase acting on activated 2-hydroxyflavanones, as an alternative means of generating flavonoid metabolites. PMID:19411659

  14. Root growth regulation and gravitropism in maize roots does not require the epidermis

    NASA Technical Reports Server (NTRS)

    Bjorkman, T.; Cleland, R. E.

    1991-01-01

    We have earlier published observations showing that endogenous alterations in growth rate during gravitropism in maize roots (Zea mays L.) are unaffected by the orientation of cuts which remove epidermal and cortical tissue in the growing zone (Bjorkman and Cleland, 1988, Planta 176, 513-518). We concluded that the epidermis and cortex are not essential for transporting a growth-regulating signal in gravitropism or straight growth, nor for regulating the rate of tissue expansion. This conclusion has been challenged by Yang et al. (1990, Planta 180, 530-536), who contend that a shallow girdle around the entire perimeter of the root blocks gravitropic curvature and that this inhibition is the result of a requirement for epidermal cells to transport the growth-regulating signal. In this paper we demonstrate that the entire epidermis can be removed without blocking gravitropic curvature and show that the position of narrow girdles does not affect the location of curvature. We therefore conclude that the epidermis is not required for transport of a growth-regulating substance from the root cap to the growing zone, nor does it regulate the growth rate of the elongating zone of roots.

  15. Overexpression of antimicrobial lytic peptides protects grapevine from Pierce's disease under greenhouse but not field conditions.

    PubMed

    Li, Zhijian T; Hopkins, Donald L; Gray, Dennis J

    2015-10-01

    Pierce's disease (PD) caused by Xylella fastidiosa prevents cultivation of grapevine (Vitis vinifera) and susceptible hybrids in the southeastern United States and poses a major threat to the grape industry of California and Texas. Genetic resistance is the only proven control of X. fastidiosa. Genetic engineering offers an alternative to heretofore ineffective conventional breeding in order to transfer only PD resistance traits into elite cultivars. A synthetic gene encoding lytic peptide LIMA-A was introduced into V. vinifera and a Vitis hybrid to assess in planta inhibition of X. fastidiosa. Over 1050 independent transgenic plant lines were evaluated in the greenhouse, among which nine lines were selected and tested under naturally-inoculated field conditions. These selected plant lines in the greenhouse remain disease-free for 10 years, to date, even with multiple manual pathogen inoculations. However, all these lines in the field, including a grafted transgenic rootstock, succumbed to PD within 7 years. We conclude that in planta production of antimicrobial lytic peptides does not provide durable PD resistance to grapevine under field conditions. PMID:25894660

  16. A novel Gateway®-compatible binary vector allows direct selection of recombinant clones in Agrobacterium tumefaciens

    PubMed Central

    2011-01-01

    Background Cloning genes into plasmid vectors is one of the key steps for studying gene function. Recently, Invitrogen™ developed a convenient Gateway® cloning system based on the site-specific DNA recombination properties of bacteriophage lambda and the cytotoxic protein ccdB, which is lethal to most E. coli strains. The ccdB protein, however, is not toxic to Agrobacterium tumefaciens, an important player often used for studying gene function in planta. This limits the direct application of the Gateway® cloning system in plant transformation-mediated research. Results In this study, we constructed a novel Gateway®-compatible destination vector, pEG101-SacB/R, by replacing the ccdB gene with a SacB-SacR gene cassette as the negative selectable marker. Conclusion Our results demonstrate that the new pEG101-SacB/R destination vector can be used for Gateway® cloning in Agrobacterium tumefaciens. pEG101-SacB/R will be a valuable tool for high-throughput functional analysis of genes in planta. PMID:22145613

  17. Global Expression Profiling of Transcription Factor Genes Provides New Insights into Pathogenicity and Stress Responses in the Rice Blast Fungus

    PubMed Central

    Park, Sook-Young; Choi, Jaeyoung; Lim, Se-Eun; Lee, Gir-Won; Park, Jongsun; Kim, Yang; Kong, Sunghyung; Kim, Se Ryun; Rho, Hee-Sool; Jeon, Junhyun; Chi, Myung-Hwan; Kim, Soonok; Khang, Chang Hyun; Kang, Seogchan; Lee, Yong-Hwan

    2013-01-01

    Because most efforts to understand the molecular mechanisms underpinning fungal pathogenicity have focused on studying the function and role of individual genes, relatively little is known about how transcriptional machineries globally regulate and coordinate the expression of a large group of genes involved in pathogenesis. Using quantitative real-time PCR, we analyzed the expression patterns of 206 transcription factor (TF) genes in the rice blast fungus Magnaporthe oryzae under 32 conditions, including multiple infection-related developmental stages and various abiotic stresses. The resulting data, which are publicly available via an online platform, provided new insights into how these TFs are regulated and potentially work together to control cellular responses to a diverse array of stimuli. High degrees of differential TF expression were observed under the conditions tested. More than 50% of the 206 TF genes were up-regulated during conidiation and/or in conidia. Mutations in ten conidiation-specific TF genes caused defects in conidiation. Expression patterns in planta were similar to those under oxidative stress conditions. Mutants of in planta inducible genes not only exhibited sensitive to oxidative stress but also failed to infect rice. These experimental validations clearly demonstrated the value of TF expression patterns in predicting the function of individual TF genes. The regulatory network of TF genes revealed by this study provides a solid foundation for elucidating how M. oryzae regulates its pathogenesis, development, and stress responses. PMID:23762023

  18. A Phytophthora infestans RXLR effector targets plant PP1c isoforms that promote late blight disease

    PubMed Central

    Boevink, Petra C.; Wang, Xiaodan; McLellan, Hazel; He, Qin; Naqvi, Shaista; Armstrong, Miles R.; Zhang, Wei; Hein, Ingo; Gilroy, Eleanor M.; Tian, Zhendong; Birch, Paul R. J.

    2016-01-01

    Plant pathogens deliver effectors to alter host processes. Knowledge of how effectors target and manipulate host proteins is critical to understand crop disease. Here, we show that in planta expression of the RXLR effector Pi04314 enhances leaf colonization by Phytophthora infestans via activity in the host nucleus and attenuates induction of jasmonic and salicylic acid-responsive genes. Pi04314 interacts with three host protein phosphatase 1 catalytic (PP1c) isoforms, causing their re-localization from the nucleolus to the nucleoplasm. Re-localization of PP1c-1 also occurs during infection and is dependent on an R/KVxF motif in the effector. Silencing the PP1c isoforms or overexpression of a phosphatase-dead PP1c-1 mutant attenuates infection, demonstrating that host PP1c activity is required for disease. Moreover, expression of PP1c–1mut abolishes enhanced leaf colonization mediated by in planta Pi04314 expression. We argue that PP1c isoforms are susceptibility factors forming holoenzymes with Pi04314 to promote late blight disease. PMID:26822079

  19. Phenylcoumaran Benzylic Ether Reductase Prevents Accumulation of Compounds Formed under Oxidative Conditions in Poplar Xylem[W

    PubMed Central

    Niculaes, Claudiu; Morreel, Kris; Kim, Hoon; Lu, Fachuang; McKee, Lauren S.; Ivens, Bart; Haustraete, Jurgen; Vanholme, Bartel; Rycke, Riet De; Hertzberg, Magnus; Fromm, Jorg; Bulone, Vincent; Polle, Andrea; Ralph, John; Boerjan, Wout

    2014-01-01

    Phenylcoumaran benzylic ether reductase (PCBER) is one of the most abundant proteins in poplar (Populus spp) xylem, but its biological role has remained obscure. In this work, metabolite profiling of transgenic poplar trees downregulated in PCBER revealed both the in vivo substrate and product of PCBER. Based on mass spectrometry and NMR data, the substrate was identified as a hexosylated 8–5-coupling product between sinapyl alcohol and guaiacylglycerol, and the product was identified as its benzyl-reduced form. This activity was confirmed in vitro using a purified recombinant PCBER expressed in Escherichia coli. Assays performed on 20 synthetic substrate analogs revealed the enzyme specificity. In addition, the xylem of PCBER-downregulated trees accumulated over 2000-fold higher levels of cysteine adducts of monolignol dimers. These compounds could be generated in vitro by simple oxidative coupling assays involving monolignols and cysteine. Altogether, our data suggest that the function of PCBER is to reduce phenylpropanoid dimers in planta to form antioxidants that protect the plant against oxidative damage. In addition to describing the catalytic activity of one of the most abundant enzymes in wood, we provide experimental evidence for the antioxidant role of a phenylpropanoid coupling product in planta. PMID:25238751

  20. Lignin cross-links with cysteine- and tyrosine-containing peptides under biomimetic conditions.

    PubMed

    Diehl, Brett G; Brown, Nicole R

    2014-10-22

    The work presented here investigates the cross-linking of various nucleophilic amino acids with lignin under aqueous conditions, thus providing insight as to which amino acids might cross-link with lignin in planta. Lignin dehydrogenation polymer (DHP) was prepared in aqueous solutions that contained tripeptides with the general structure XGG, where X represents an amino acid with a nucleophilic side chain. Fourier-transform infrared spectroscopy and energy dispersive X-ray spectroscopy showed that peptides containing cysteine and tyrosine were incorporated into the DHP to form DHP-CGG and DHP-YGG adducts, whereas peptides containing other nucleophilic amino acids were not incorporated. Scanning electron microscopy showed that the physical morphology of DHP was altered by the presence of peptides in the aqueous solution, regardless of peptide incorporation into the DHP. Nuclear magnetic resonance (NMR) spectroscopy showed that cysteine-containing peptide cross-linked with lignin at the lignin α-position, whereas in the case of the lignin-tyrosine adduct the exact cross-linking pathway could not be determined. This is the first study to use NMR to confirm cross-linking between lignin and peptides under biomimetic conditions. The results of this study may indicate the potential for lignin-protein linkage formation in planta, particularly between lignin and cysteine- and/or tyrosine-rich proteins. PMID:25275918

  1. Externally imposed electric field enhances plant root tip regeneration

    PubMed Central

    Kral, Nicolas; Hanna Ougolnikova, Alexandra

    2016-01-01

    Abstract In plants, shoot and root regeneration can be induced in the distinctive conditions of tissue culture (in vitro) but is also observed in intact individuals (in planta) recovering from tissue damage. Roots, for example, can regenerate their fully excised meristems in planta, even in mutants with impaired apical stem cell niches. Unfortunately, to date a comprehensive understanding of regeneration in plants is still missing. Here, we provide evidence that an imposed electric field can perturb apical root regeneration in Arabidopsis. Crucially, we explored both spatial and temporal competences of the stump to respond to electrical stimulation, by varying respectively the position of the cut and the time interval between excision and stimulation. Our data indicate that a brief pulse of an electric field parallel to the root is sufficient to increase by up to two‐fold the probability of its regeneration, and to perturb the local distribution of the hormone auxin, as well as cell division regulation. Remarkably, the orientation of the root towards the anode or the cathode is shown to play a role. PMID:27606066

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

    PubMed

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

    2016-01-01

    Rice bean (Vigna umbellata) VuMATE1 appears to be constitutively expressed at vascular system but root apex, and Al stress extends its expression to root apex. Whether VuMATE1 participates in both Al tolerance and Fe nutrition, and how VuMATE1 expression is regulated is of great interest. In this study, the role of VuMATE1 in Fe nutrition was characterized through in planta complementation assays. The transcriptional regulation of VuMATE1 was investigated through promoter analysis and promoter-GUS reporter assays. The results showed that the expression of VuMATE1 was regulated by Al stress but not Fe status. Complementation of frd3-1 with VuMATE1 under VuMATE1 promoter could not restore phenotype, but restored with 35SCaMV promoter. Immunostaining of VuMATE1 revealed abnormal localization of VuMATE1 in vasculature. In planta GUS reporter assay identified Al-responsive cis-acting elements resided between -1228 and -574 bp. Promoter analysis revealed several cis-acting elements, but transcription is not simply regulated by one of these elements. We demonstrated that cis regulation of VuMATE1 expression is involved in Al tolerance mechanism, while not involved in Fe nutrition. These results reveal the evolution of VuMATE1 expression for better adaptation of rice bean to acid soils where Al stress imposed but Fe deficiency pressure released. PMID:27148333

  3. Phylobiochemical Characterization of Class-Ib Aspartate/Prephenate Aminotransferases Reveals Evolution of the Plant Arogenate Phenylalanine Pathway[W

    PubMed Central

    Dornfeld, Camilla; Weisberg, Alexandra J.; K C, Ritesh; Dudareva, Natalia; Jelesko, John G.; Maeda, Hiroshi A.

    2014-01-01

    The aromatic amino acid Phe is required for protein synthesis and serves as the precursor of abundant phenylpropanoid plant natural products. While Phe is synthesized from prephenate exclusively via a phenylpyruvate intermediate in model microbes, the alternative pathway via arogenate is predominant in plant Phe biosynthesis. However, the molecular and biochemical evolution of the plant arogenate pathway is currently unknown. Here, we conducted phylogenetically informed biochemical characterization of prephenate aminotransferases (PPA-ATs) that belong to class-Ib aspartate aminotransferases (AspAT Ibs) and catalyze the first committed step of the arogenate pathway in plants. Plant PPA-ATs and succeeding arogenate dehydratases (ADTs) were found to be most closely related to homologs from Chlorobi/Bacteroidetes bacteria. The Chlorobium tepidum PPA-AT and ADT homologs indeed efficiently converted prephenate and arogenate into arogenate and Phe, respectively. A subset of AspAT Ib enzymes exhibiting PPA-AT activity was further identified from both Plantae and prokaryotes and, together with site-directed mutagenesis, showed that Thr-84 and Lys-169 play key roles in specific recognition of dicarboxylic keto (prephenate) and amino (aspartate) acid substrates. The results suggest that, along with ADT, a gene encoding prephenate-specific PPA-AT was transferred from a Chlorobi/Bacteroidetes ancestor to a eukaryotic ancestor of Plantae, allowing efficient Phe and phenylpropanoid production via arogenate in plants today. PMID:25070637

  4. Antagonism of Pythium blight of zucchini by Hypocrea jecorina does not require cellulase gene expression but is improved by carbon catabolite derepression.

    PubMed

    Seidl, Verena; Schmoll, Monika; Scherm, Barbara; Balmas, Virgilio; Seiboth, Bernhard; Migheli, Quirico; Kubicek, Christian P

    2006-04-01

    Toward a better understanding of the biochemical events that lead to biocontrol of plant pathogenic fungi by Hypocrea/Trichoderma spp., we investigated the importance of carbon catabolite (de)repression and cellulase formation in the antagonization of Pythium ultimum by Hypocrea jecorina (Trichoderma reesei) on agar plates and in planta. Hypocrea jecorina QM9414 could antagonize and overgrow P. ultimum but not Rhizoctonia solani in plate confrontation tests, and provided significant protection of zucchini plants against P. ultimum blight in planta. A carbon catabolite derepressed cre1 mutant of H. jecorina antagonized P. ultimum on plates more actively and increased the survival rates of P. ultimum-inoculated zucchini plants in comparison with strain QM9414. A H. jecorina mutant impaired in cellulase induction could also antagonize P. ultimum on plates and provided the same level of protection of zucchini plants against P. ultimum as strain QM9414 did. We conclude that cellulase formation is dispensable for biocontrol of P. ultimum, whereas carbon catabolite derepression increases the antagonistic ability by apparently acting on other target genes. PMID:16553845

  5. [A study on effectiveness of treatment and prevention of relapse using topical administration of terbinafine in a guinea pig model for tinea pedis].

    PubMed

    Uchida, K; Kudoh, M; Yamaguchi, H

    1994-10-01

    The effectiveness of topical terbinafine (TBF) to tinea pedis was evaluated an animal model in which guinea pigs were experimentally infected through their planta pedis with Trichophyton mentagrophytes, then a 1% TBF or butenafine (BTF) cream was administered topically once daily for 4 consecutive weeks. The therapeutic efficacy was assessed on the basis of recovery of fungal cultures from the planta pedis. The cured guinea pigs were reared in a clean environment that protected the animals from reinfection. The dermal tissues were cultured 2, 4, and 8 weeks post-treatment to examine for relapse of tinea. Complete cure was achieved after 4 weeks of administration of TBF or BTF cream. In animals receiving 4 weeks of treatment with TBF, relapse was not observed up to 8 weeks after the termination of treatment. In animals treated with BTF for 4 weeks, while no relapse occurred 4 weeks after cessation of the treatment, relapse was detected in 2 out of 10 feet at 8 weeks after the termination of treatment. These results suggest that topical TBF is effective in curing the infection and in preventing relapse in a guinea pig model of tinea pedis. PMID:7807700

  6. The Anti-Phytophthora Effect of Selected Potato-Associated Pseudomonas Strains: From the Laboratory to the Field

    PubMed Central

    Guyer, Anouk; De Vrieze, Mout; Bönisch, Denise; Gloor, Ramona; Musa, Tomke; Bodenhausen, Natacha; Bailly, Aurélien; Weisskopf, Laure

    2015-01-01

    Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late blight is controlled by repeated applications of copper-based products, which negatively impact the environment. To find alternative solutions for late blight management, we have previously isolated a large collection of bacteria from the phyllosphere and the rhizosphere of potatoes. Here we report the antagonistic potential of these strains when co-cultivated with P. infestans as well as with other potato pathogens. We then focused on three Pseudomonas strains and compared their protective impact against late blight to that of well-known biocontrol strains in planta using a high-throughput leaf disk assay with automated picture analysis. When sprayed on the leaves of potatoes in the greenhouse, the strains were able to survive for at least 15 days. Under field conditions, populations decreased faster but all tested strains could still be retrieved after 8 days. The most active strain in vitro, P. chlororaphis R47, was also the best protectant on leaf disks from plants grown in the greenhouse experiment, but its protection potential could not be verified in the field due to unfavorable infection conditions. However, its protective effect against P. infestans in planta, its survival in the phyllosphere as well as its ability to colonize the potato rhizosphere in very high population densities, suggest a potential for field application, e.g., in the form of tuber treatment or leaf spray. PMID:26640460

  7. Mining secreted proteins that function in pepper fruit development and ripening using a yeast secretion trap (YST)

    SciTech Connect

    Lee, Je Min; Lee, Sang-Jik; Rose, Jocelyn K.C.; Yeam, Inhwa; Kim, Byung-Dong

    2014-04-18

    Highlights: • Yeast secretion trap (YST) is a valuable tool for mining secretome. • A total of 80 secreted proteins are newly identified via YST in pepper fruits. • The secreted proteins are differentially regulated during pepper development and ripening. • Transient GFP-fusion assay and in planta secretion trap can effectively validate the secretion of proteins. - Abstract: Plant cells secrete diverse sets of constitutively- and conditionally-expressed proteins under various environmental and developmental states. Secreted protein populations, or secretomes have multiple functions, including defense responses, signaling, metabolic processes, and developmental regulation. To identify genes encoding secreted proteins that function in fruit development and ripening, a yeast secretion trap (YST) screen was employed using pepper (Capsicum annuum) fruit cDNAs. The YST screen revealed 80 pepper fruit-related genes (CaPFRs) encoding secreted proteins including cell wall proteins, several of which have not been previously described. Transient GFP-fusion assay and an in planta secretion trap were used to validate the secretion of proteins encoded by selected YST clones. In addition, RNA gel blot analyses provided further insights into their expression and regulation during fruit development and ripening. Integrating our data, we conclude that the YST provides a valuable functional genomics tool for the identification of substantial numbers of novel secreted plant proteins that are associated with biological processes, including fruit development and ripening.

  8. Metal binding to the N-terminal cytoplasmic domain of the PIB ATPase HMA4 is required for metal transport in Arabidopsis.

    PubMed

    Laurent, Clémentine; Lekeux, Gilles; Ukuwela, Ashwinie A; Xiao, Zhiguang; Charlier, Jean-Benoit; Bosman, Bernard; Carnol, Monique; Motte, Patrick; Damblon, Christian; Galleni, Moreno; Hanikenne, Marc

    2016-03-01

    PIB ATPases are metal cation pumps that transport metals across membranes. These proteins possess N- and C-terminal cytoplasmic extensions that contain Cys- and His-rich high affinity metal binding domains, which may be involved in metal sensing, metal ion selectivity and/or in regulation of the pump activity. The PIB ATPase HMA4 (Heavy Metal ATPase 4) plays a central role in metal homeostasis in Arabidopsis thaliana and has a key function in zinc and cadmium hypertolerance and hyperaccumulation in the extremophile plant species Arabidopsis halleri. Here, we examined the function and structure of the N-terminal cytoplasmic metal-binding domain of HMA4. We mutagenized a conserved CCTSE metal-binding motif in the domain and assessed the impact of the mutations on protein function and localization in planta, on metal-binding properties in vitro and on protein structure by Nuclear Magnetic Resonance spectroscopy. The two Cys residues of the motif are essential for the function, but not for localization, of HMA4 in planta, whereas the Glu residue is important but not essential. These residues also determine zinc coordination and affinity. Zinc binding to the N-terminal domain is thus crucial for HMA4 protein function, whereas it is not required to maintain the protein structure. Altogether, combining in vivo and in vitro approaches in our study provides insights towards the molecular understanding of metal transport and specificity of metal P-type ATPases. PMID:26797794

  9. The future of starch bioengineering: GM microorganisms or GM plants?

    PubMed Central

    Hebelstrup, Kim H.; Sagnelli, Domenico; Blennow, Andreas

    2015-01-01

    Plant starches regularly require extensive modification to permit subsequent applications. Such processing is usually done by the use of chemical and/or physical treatments. The use of recombinant enzymes produced by large-scale fermentation of GM microorganisms is increasingly used in starch processing and modification, sometimes as an alternative to chemical or physical treatments. However, as a means to impart the modifications as early as possible in the starch production chain, similar recombinant enzymes may also be expressed in planta in the developing starch storage organ such as in roots, tubers and cereal grains to provide a GM crop as an alternative to the use of enzymes from GM microorganisms. We here discuss these techniques in relation to important structural features and modifications of starches such as: starch phosphorylation, starch hydrolysis, chain transfer/branching and novel concepts of hybrid starch-based polysaccharides. In planta starch bioengineering is generally challenged by yield penalties and inefficient production of the desired product. However, in some situations, GM crops for starch bioengineering without deleterious effects have been achieved. PMID:25954284

  10. Biodegradation of atrazine in transgenic plants expressing a modified bacterial atrazine chlorohydrolase (atzA) gene.

    PubMed

    Wang, Lin; Samac, Deborah A; Shapir, Nir; Wackett, Lawrence P; Vance, Carroll P; Olszewski, Neil E; Sadowsky, Michael J

    2005-09-01

    Atrazine is one of the most widely used herbicides in the USA. Atrazine chlorohydrolase (AtzA), the first enzyme in a six-step pathway leading to the mineralization of atrazine in Gram-negative soil bacteria, catalyses the hydrolytic dechlorination and detoxification of atrazine to hydroxyatrazine. In this study, we investigated the potential use of transgenic plants expressing atzA to take up, dechlorinate and detoxify atrazine. Alfalfa, Arabidopsis thaliana and tobacco were transformed with a modified bacterial atzA gene, p-atzA, under the control of the cassava vein mosaic virus promoter. All transgenic plant species actively expressed p-atzA and grew over a wide range of atrazine concentrations. Thin layer chromatography analyses indicated that in planta expression of p-atzA resulted in the production of hydroxyatrazine. Hydroponically grown transgenic tobacco and alfalfa dechlorinated atrazine to hydroxyatrazine in leaves, stems and roots. Moreover, p-atzA was found to be useful as a conditional-positive selection system to isolate alfalfa and Arabidopsis transformants following Agrobacterium-mediated transformation. Our work suggests that the in planta expression of p-atzA may be useful for the development of plants for the phytoremediation of atrazine-contaminated soils and soil water, and as a marker gene to select for the integration of exogenous DNA into the plant genome. PMID:17173634

  11. Two Arabidopsis ADP-Glucose Pyrophosphorylase Large Subunits (APL1 and APL2) Are Catalytic1

    PubMed Central

    Ventriglia, Tiziana; Kuhn, Misty L.; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A.; Preiss, Jack; Romero, José M.

    2008-01-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (α2β2) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1–APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  12. Two Arabidopsis ADP-glucose pyrophosphorylase large subunits (APL1 and APL2) are catalytic.

    PubMed

    Ventriglia, Tiziana; Kuhn, Misty L; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A; Preiss, Jack; Romero, José M

    2008-09-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (alpha(2)beta(2)) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1-APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  13. Arabidopsis ABCG14 protein controls the acropetal translocation of root-synthesized cytokinins

    NASA Astrophysics Data System (ADS)

    Zhang, Kewei; Novak, Ondrej; Wei, Zhaoyang; Gou, Mingyue; Zhang, Xuebin; Yu, Yong; Yang, Huijun; Cai, Yuanheng; Strnad, Miroslav; Liu, Chang-Jun

    2014-02-01

    Cytokinins are a major group of phytohormones regulating plant growth, development and stress responses. However, in contrast to the well-defined polar transport of auxins, the molecular basis of cytokinin transport is poorly understood. Here we show that an ATP-binding cassette transporter in Arabidopsis, AtABCG14, is essential for the acropetal (root to shoot) translocation of the root-synthesized cytokinins. AtABCG14 is expressed primarily in the pericycle and stelar cells of roots. Knocking out AtABCG14 strongly impairs the translocation of trans-zeatin (tZ)-type cytokinins from roots to shoots, thereby affecting the plant’s growth and development. AtABCG14 localizes to the plasma membrane of transformed cells. In planta feeding of C14 or C13-labelled tZ suggests that it acts as an efflux pump and its presence in the cells directly correlates with the transport of the fed cytokinin. Therefore, AtABCG14 is a transporter likely involved in the long-distance translocation of cytokinins in planta.

  14. The Anti-Phytophthora Effect of Selected Potato-Associated Pseudomonas Strains: From the Laboratory to the Field.

    PubMed

    Guyer, Anouk; De Vrieze, Mout; Bönisch, Denise; Gloor, Ramona; Musa, Tomke; Bodenhausen, Natacha; Bailly, Aurélien; Weisskopf, Laure

    2015-01-01

    Late blight, caused by the oomycete Phytophthora infestans, is the most devastating disease of potato. In organic farming, late blight is controlled by repeated applications of copper-based products, which negatively impact the environment. To find alternative solutions for late blight management, we have previously isolated a large collection of bacteria from the phyllosphere and the rhizosphere of potatoes. Here we report the antagonistic potential of these strains when co-cultivated with P. infestans as well as with other potato pathogens. We then focused on three Pseudomonas strains and compared their protective impact against late blight to that of well-known biocontrol strains in planta using a high-throughput leaf disk assay with automated picture analysis. When sprayed on the leaves of potatoes in the greenhouse, the strains were able to survive for at least 15 days. Under field conditions, populations decreased faster but all tested strains could still be retrieved after 8 days. The most active strain in vitro, P. chlororaphis R47, was also the best protectant on leaf disks from plants grown in the greenhouse experiment, but its protection potential could not be verified in the field due to unfavorable infection conditions. However, its protective effect against P. infestans in planta, its survival in the phyllosphere as well as its ability to colonize the potato rhizosphere in very high population densities, suggest a potential for field application, e.g., in the form of tuber treatment or leaf spray. PMID:26640460

  15. Expression of anti-tumor necrosis factor alpha (TNFα) single-chain variable fragment (scFv) in Spirodela punctata plants transformed with Agrobacterium tumefaciens.

    PubMed

    Balaji, Parthasarathy; Satheeshkumar, P K; Venkataraman, Krishnan; Vijayalakshmi, M A

    2016-05-01

    Therapeutic antibodies against tumor necrosis factor alpha (TNFα) have been considered effective for some of the autoimmune diseases such as rheumatoid arthritis, Crohn's diseases, and so on. But associated limitations of the current therapeutics in terms of cost, availability, and immunogenicity have necessitated the need for alternative candidates. Single-chain variable fragment (scFv) can negate the limitations tagged with the anti-TNFα therapeutics to a greater extent. In the present study, Spirodela punctata plants were transformed with anti-TNFα through in planta transformation using Agrobacterium tumefaciens strain, EHA105. Instead of cefotaxime, garlic extract (1 mg/mL) was used to remove the agrobacterial cells after cocultivation. To the best of our knowledge, this report shows for the first time the application of plant extracts in transgenic plant development. 95% of the plants survived screening under hygromycin. ScFv cDNA integration in the plant genomic DNA was confirmed at the molecular level by PCR. The transgenic protein expression was followed up to 10 months. Expression of scFv was confirmed by immunodot blot. Protein expression levels of up to 6.3% of total soluble protein were observed. β-Glucuronidase and green fluorescent protein expressions were also detected in the antibiotic resistant plants. The paper shows the generation of transgenic Spirodela punctuata plants through in planta transformation. PMID:25786575

  16. Somatic embryogenesis - Stress-induced remodeling of plant cell fate.

    PubMed

    Fehér, Attila

    2015-04-01

    Plants as sessile organisms have remarkable developmental plasticity ensuring heir continuous adaptation to the environment. An extreme example is somatic embryogenesis, the initiation of autonomous embryo development in somatic cells in response to exogenous and/or endogenous signals. In this review I briefly overview the various pathways that can lead to embryo development in plants in addition to the fertilization of the egg cell and highlight the importance of the interaction of stress- and hormone-regulated pathways during the induction of somatic embryogenesis. Somatic embryogenesis can be initiated in planta or in vitro, directly or indirectly, and the requirement for dedifferentiation as well as the way to achieve developmental totipotency in the various systems is discussed in light of our present knowledge. The initiation of all forms of the stress/hormone-induced in vitro as well as the genetically provoked in planta somatic embryogenesis requires extensive and coordinated genetic reprogramming that has to take place at the chromatin level, as the embryogenic program is under strong epigenetic repression in vegetative plant cells. Our present knowledge on chromatin-based mechanisms potentially involved in the somatic-to-embryogenic developmental transition is summarized emphasizing the potential role of the chromatin to integrate stress, hormonal, and developmental pathways leading to the activation of the embryogenic program. The role of stress-related chromatin reorganization in the genetic instability of in vitro cultures is also discussed. This article is part of a Special Issue entitled: Stress as a fundamental theme in cell plasticity. PMID:25038583

  17. Fruit and vegetable exposure in children is linked to the selection of a wider variety of healthy foods at school.

    PubMed

    Korinek, Elizabeth V; Bartholomew, John B; Jowers, Esbelle M; Latimer, Lara A

    2015-10-01

    Schools often offer healthy fruits and vegetables (FV) and healthy entrées. However, children may resist these efforts due to a lack of familiarity with the offerings. While numerous exposures with a food increase its liking, it may be that an exposure to a variety of FV at home leads to greater willingness to select other foods - even those that are unrelated to those eaten at home. As an initial test of this possibility, this study was designed to examine how self-reports of exposure and consumption of various FV were associated with the selection of FV and lunch entrées at school. Participants (n = 59) were a convenience sample of elementary children. A median split was used to place students into high- and low-exposure groups for self-reports of both exposure and consumption at home. The primary dependent variables were self-reports of selecting FV at school; the children's absolute and relative ratings of eight 'healthier' lunch entrées; and self-reports of selecting these entrées. These entrées were recently added to the school menu and, therefore, tended to be less familiar to children. Food ratings were collected through taste exposures conducted at school. Results indicate that children who reported more frequent exposure to FV at home consumed a wider variety of FV at school and were more likely to report selecting 'healthier' entrées at school lunch. These data suggest that exposure to, and the consumption of, a variety of FV may make children more willing to select a wider range of FV and other healthy entrées. PMID:23557428

  18. El rol de Ia colaboracion y el Modelo de Aprendizaje Basado en Proyectos (ABPr) mediante el lente de la Teoria de Actividad (CHAT): un estudio de caso con estudiantes de 9no grado

    NASA Astrophysics Data System (ADS)

    Delgado, Isabel C.

    Los modelos de eensenanza y aprendizaje constructivistas conceptualizan el aprendizaje como un proceso activo. El modelo de Aprendizaje Basado en Proyectos (ABPr) se distingue por una serie de componentes, entre los cuales se destaca el aspecto colaborativo y cooperativo como un reto al momento de su implantacion. Son pocas las investigaciones que se concentran en este aspecto del modelo. En este estudio, se analizaron las diversas interacciones que surgen durante la implantacion de una unidad curricular sobre el tema de Geologia de Puerto Rico, la cual se diseno con el modelo ABPr cuyo enfoque es orientacion a proyectos. Particularmente, se examinaron las interacciones sociales que surgen entre los pares y entre pares y docente durante el proceso de planificacion y desarrollo de los productos finales, al igual que las interacciones entre los estudiantes y el material didactico en estas etapas del modelo. La investigacion es de tipo cualitativo e incorpora como diseno el estudio de caso. Las diversas interacciones constituyen la unidad de analisis. En el estudio participaron 19 estudiantes de 9no grado, a quienes se organizaron en 5 grupos colaborativos por temas de interes (Pangea, Placas tectonicas, Volcanes, Tsunamis y Terremotos). Las tecnicas que se utilizaron para recopilar los datos fueron: observaciones participativas, grupos focales y analisis de documentos (cuadernos reflexivos y respuestas de los estudiantes a la pregunta central del proyecto). Para el analisis de los datos se aplico la teoria de actividad (CHAT) que concentra la unidad de analisis en la actividad humana en un contexto particular. Los resultados del estudio senalan que las interacciones entre pares, entre pares y docente, asi como entre estudiantes y material didactico son fundamentales en el proceso de aprendizaje. Una mayor interaccion entre pares durante las etapas de planificar y desarrollar los productos finales de la unidad, promueve una mejor comprension de los conceptos de la

  19. Distinct colonization patterns and cDNA-AFLP transcriptome profiles in compatible and incompatible interactions between melon and different races of Fusarium oxysporum f. sp. melonis

    PubMed Central

    2011-01-01

    Background Fusarium oxysporum f. sp. melonis Snyd. & Hans. (FOM) causes Fusarium wilt, the most important infectious disease of melon (Cucumis melo L.). The four known races of this pathogen can be distinguished only by infection on appropriate cultivars. No molecular tools are available that can discriminate among the races, and the molecular basis of compatibility and disease progression are poorly understood. Resistance to races 1 and 2 is controlled by a single dominant gene, whereas only partial polygenic resistance to race 1,2 has been described. We carried out a large-scale cDNA-AFLP analysis to identify host genes potentially related to resistance and susceptibility as well as fungal genes associated with the infection process. At the same time, a systematic reisolation procedure on infected stems allowed us to monitor fungal colonization in compatible and incompatible host-pathogen combinations. Results Melon plants (cv. Charentais Fom-2), which are susceptible to race 1,2 and resistant to race 1, were artificially infected with a race 1 strain of FOM or one of two race 1,2 w strains. Host colonization of stems was assessed at 1, 2, 4, 8, 14, 16, 18 and 21 days post inoculation (dpi), and the fungus was reisolated from infected plants. Markedly different colonization patterns were observed in compatible and incompatible host-pathogen combinations. Five time points from the symptomless early stage (2 dpi) to obvious wilting symptoms (21 dpi) were considered for cDNA-AFLP analysis. After successful sequencing of 627 transcript-derived fragments (TDFs) differentially expressed in infected plants, homology searching retrieved 305 melon transcripts, 195 FOM transcripts expressed in planta and 127 orphan TDFs. RNA samples from FOM colonies of the three strains grown in vitro were also included in the analysis to facilitate the detection of in planta-specific transcripts and to identify TDFs differentially expressed among races/strains. Conclusion Our data

  20. Accumulation of methylmercury in rice and flooded soil in experiments with an enriched isotopic Hg(II) tracer

    NASA Astrophysics Data System (ADS)

    Strickman, R. J.; Mitchell, C. P. J.

    2015-12-01

    Methylmercury (MeHg) is a neurotoxin produced in anoxic aquatic sediments. Numerous factors, including the presence of aquatic plants, alter the biogeochemistry of sediments, affecting the rate at which microorganisms transform bioavailable inorganic Hg (IHg) to MeHg. Methylmercury produced in flooded paddy soils and its transfer into rice has become an important dietary consideration. An improved understanding of how MeHg reaches the grain and the extent to which rice alters MeHg production in rhizosphere sediments could help to inform rice cultivation practices. We conducted a controlled greenhouse experiment with thirty rice plants grown in individual, flooded pots amended with enriched 200Hg. Unvegetated controls were maintained under identical conditions. At three plant growth stages (vegetative growth, flowering, and grain maturity), ten plants were sacrificed and samples collected from soil, roots, straw, panicle, and grain of vegetated and unvegetated pots, and assessed for MeHg and THg concentrations. We observed consistent ratios between ambient and tracer MeHg between soils (0.36 ±0.04 — 0.44 ± 0.09) and plant compartments (0.23 ± 0.07 -0.34 ± 0.05) indicating that plant MeHg contamination originates in the soil rather than in planta methylation. The majority of this MeHg was absorbed between the tillering (4.48 ± 2.38 ng/plant) and flowering (8.43 ± 5.12 ng/pl) phases, with a subsequent decline at maturity (2.87 ± 1.23 ng/pl) only partly explained by translocation to the developing grain, indicating that MeHg was demethylated in planta. In contrast, IHg was absorbed from both soil and air, as evidenced by the higher ambient IHg concentrations compared to tracer (3.76 ± 1.19 vs. 0.27 ± 0.40 ng/g). Surprisingly, MeHg accumulation was significantly (p= 0.042-- 0.003) lower in vegetated vs. unvegetated sediments at flowering (1.41 ± 0.26 vs. 1.57 ± 0.23) and maturity (1.27 ± 0.22 vs. 1.71 ± 0.25), suggesting that plant exudates bound Hg