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34 results on '"Gay, Gilles"'

1. Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

Author

Kohler, Annegret, Kuo, Alan, Nagy, Laszlo G, Morin, Emmanuelle, Barry, Kerrie W, Buscot, Francois, Canbäck, Björn, Choi, Cindy, Cichocki, Nicolas, Clum, Alicia, Colpaert, Jan, Copeland, Alex, Costa, Mauricio D, Doré, Jeanne, Floudas, Dimitrios, Gay, Gilles, Girlanda, Mariangela, Henrissat, Bernard, Herrmann, Sylvie, Hess, Jaqueline, Högberg, Nils, Johansson, Tomas, Khouja, Hassine-Radhouane, LaButti, Kurt, Lahrmann, Urs, Levasseur, Anthony, Lindquist, Erika A, Lipzen, Anna, Marmeisse, Roland, Martino, Elena, Murat, Claude, Ngan, Chew Y, Nehls, Uwe, Plett, Jonathan M, Pringle, Anne, Ohm, Robin A, Perotto, Silvia, Peter, Martina, Riley, Robert, Rineau, Francois, Ruytinx, Joske, Salamov, Asaf, Shah, Firoz, Sun, Hui, Tarkka, Mika, Tritt, Andrew, Veneault-Fourrey, Claire, Zuccaro, Alga, Tunlid, Anders, Grigoriev, Igor V, Hibbett, David S, and Martin, Francis

Published
2015

10. The Hebeloma cylindrosporum HcPT2 Pi transporter plays a key role in ectomycorrhizal symbiosis

Author

Becquer, Adeline, primary, Garcia, Kevin, additional, Amenc, Laurie, additional, Rivard, Camille, additional, Doré, Jeanne, additional, Trives‐Segura, Carlos, additional, Szponarski, Wojciech, additional, Russet, Sylvie, additional, Baeza, Yoan, additional, Lassalle‐Kaiser, Benedikt, additional, Gay, Gilles, additional, Zimmermann, Sabine Dagmar, additional, and Plassard, Claude, additional

Published
2018
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12. The ectomycorrhizal basidiomycete Hebeloma cylindrosporum undergoes early waves of transcriptional reprogramming prior to symbiotic structures differentiation

Author

DORE, Jeanne, Kohler, Annegret, Dubost, Audrey, Hundley, Hope, Singan, Vasanth, Peng, Yi, Kuo, Alan, Grigoriev, Igor V., Martin, Francis, Marmeisse, Roland, Gay, Gilles, Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Ecole Nationale Vétérinaire de Lyon (ENVL), Interactions Arbres-Microorganismes (IAM), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Dept Energy Great Lakes Bioenergy Res Ctr, Community Science Program (Mycorrhizal Genomics Initiative: Exploring the Symbiotic Transcriptomes) - U.S. Department of Energy Joint Genome Institute 978, DOE Office of Science User FacilityOffice of Science of the U.S. Department of Energy DE-AC02-05CH11231, French National Institute for Agricultural Research (INRA), US Department of Energy (DOE) Joint Genome Institute (JGI), Office of Science of the US Department of Energy, Region Lorraine Research Council, European Commission (European Regional Development Fund (ERDF)), Laboratory of Excellence Advanced Research on the Biology of Tree and Forest Ecosystems (ARBRE) ANR-11-LABX-0002-01, US DOE through the Oak Ridge National Laboratory Scientific Focus Area for Genomics Foundational Sciences (Plant Microbe Interfaces Project), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Vétérinaire de Lyon (ENVL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), Université de Lorraine (UL)-Institut National de la Recherche Agronomique (INRA), Ecologie microbienne ( EM ), Centre National de la Recherche Scientifique ( CNRS ) -Ecole Nationale Vétérinaire de Lyon ( ENVL ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique ( INRA ) -VetAgro Sup ( VAS ), Interactions Arbres-Microorganismes ( IAM ), and Institut National de la Recherche Agronomique ( INRA ) -Université de Lorraine ( UL )

Subjects
Mycelium, Proteome, bactérie symbiotique, fungi, Pinus, Plant Roots, Up-Regulation, Fungal Proteins, interaction moléculaire, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [ SDV.MP ] Life Sciences [q-bio]/Microbiology and Parasitology, Mycorrhizae, molecular interaction, Hebeloma, basidiomycète, Symbiosis, transcriptome
Abstract

To clarify the early molecular interaction between ectomycorrhizal partners, we performed a RNA-Seq study of transcriptome reprogramming of the basidiomycete Hebeloma cylindrosporum before symbiotic structure differentiation with Pinus pinaster. Mycorrhiza transcriptome was studied for comparison. By reference to asymbiotic mycelium, 47 and 46 genes were specifically upregulated over fivefold (p ≤ 0.05) upon rhizosphere colonization and root adhesion respectively. Other 45 were upregulated throughout the symbiotic interaction, from rhizosphere colonization to differentiated mycorrhizas, whereas 274 were specifically upregulated in mycorrhizas. Although exoproteome represents 5.6% of H. cylindrosporum proteome, 38.5% of the genes upregulated upon pre-infectious root colonization encoded extracellular proteins. The proportion decreased to 23.5% in mycorrhizas. At all studied time points, mycorrhiza-induced small secreted proteins (MiSSPs), representing potential effectors, were over-represented among upregulated genes. This was also the case for carbohydrate-active enzymes (CAZymes). Several CAZymes were upregulated at all studied stages of the interaction. Consistent with a role in fungal morphogenesis and symbiotic interface differentiation, CAZymes over-expressed before and upon root attachment targeted fungal and both fungal and plant polysaccharides respectively. Different hydrophobins were upregulated upon early root adhesion, in mycorrhizas or throughout interaction. The functional classification of genes upregulated only in mycorrhizas pointed to intense metabolic activity and nutritional exchanges.

Published
2017
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14. Comparative genomics, proteomics and transcriptomics give new insight into the exoproteome of the basidiomycete Hebeloma cylindrosporum and its involvement in ectomycorrhizal symbiosis

Author

DORE, Jeanne, PERRAUD, Marie, Dieryckx, Cindy, Kohler, Annegret, Morin, Emmanuelle, Henrissat, Bernard, Lindquist, Erika, Zimmermann, Sabine D., Girard, Vincent, Kuo, Alan, Grigoriev, Igor V, Martin, Francis, Marmeisse, Roland, Gay, Gilles, Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Génomique fonctionnelle des champignons pathogènes des plantes (FungiPath), Microbiologie, adaptation et pathogénie (MAP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Interactions Arbres-Microorganismes (IAM), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Architecture et fonction des macromolécules biologiques (AFMB), Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Department of Energy / Joint Genome Institute (DOE), Los Alamos National Laboratory (LANL), Biochimie et Physiologie Moléculaire des Plantes (BPMP), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), U.S. Department of Energy (DE-AC02-05CH11231), ANR (ANR-11-607 LABX-0002-01), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Vétérinaire de Lyon (ENVL)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique (INRA)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS), Université de Lorraine (UL)-Institut National de la Recherche Agronomique (INRA), Université de Montpellier (UM)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS), Ecologie microbienne ( EM ), Centre National de la Recherche Scientifique ( CNRS ) -Ecole Nationale Vétérinaire de Lyon ( ENVL ) -Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de la Recherche Agronomique ( INRA ) -VetAgro Sup ( VAS ), Microbiologie, adaptation et pathogénie ( MAP ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Interactions Arbres-Microorganismes ( IAM ), Institut National de la Recherche Agronomique ( INRA ) -Université de Lorraine ( UL ), Architecture et fonction des macromolécules biologiques ( AFMB ), Centre National de la Recherche Scientifique ( CNRS ) -Aix Marseille Université ( AMU ) -Institut National de la Recherche Agronomique ( INRA ), DOE Joint Genome Institute, Biochimie et Physiologie Moléculaire des Plantes ( BPMP ), Centre international d'études supérieures en sciences agronomiques ( Montpellier SupAgro ) -Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Ecole Nationale Vétérinaire de Lyon (ENVL), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon, Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Proteomics, [SDV.OT]Life Sciences [q-bio]/Other [q-bio.OT], Hebeloma cylindrosporum, Proteome, Genes, Fungal, fungi, Genomics, exoproteome, shotgun protein quantification, ectomycorrhiza, Fungal Proteins, Mycorrhizae, soil organic matter, Hebeloma, [ SDV.OT ] Life Sciences [q-bio]/Other [q-bio.OT], Symbiosis, transcriptome
Abstract

Extracellular proteins play crucial roles in the interaction between mycorrhizal fungi and their environment. Computational prediction and experimental detection allowed identification of 869 proteins constituting the exoproteome of Hebeloma cylindrosporum. Small secreted proteins (SSPs) and carbohydrate-active enzymes (CAZymes) were the two major classes of extracellular proteins. Twenty-eight per cent of the SSPs were secreted by free-living mycelia and five of the 10 most abundant extracellular proteins were SSPs. By contrast, 63-75% of enzymes involved in nutrient acquisition were secreted. A total of 150 extracellular protein-coding genes were differentially expressed between mycorrhizas and free-living mycelia. SSPs were the most affected. External environmental conditions also affected expression of 199 exoproteome genes in mycorrhizas. SSPs displayed different patterns of regulation in response to presence of a host plant or other environmental signals. Several of the genes most overexpressed in the presence of organic matter encoded oxidoreductases. Hebeloma cylindrosporum has not fully lost its ancestral saprotrophic capacities but rather adapted them not to harm its hosts and to use soil organic nitrogen. The complex and divergent patterns of regulation of SSPs in response to a symbiotic partner and/or organic matter suggest various roles in the biology of mycorrhizal fungi.

Published
2015
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15. Comparative genomics, proteomics and transcriptomics give new insight into the exoproteome of the basidiomyceteH ebeloma cylindrosporumand its involvement in ectomycorrhizal symbiosis

Author

Doré, Jeanne, primary, Perraud, Marie, additional, Dieryckx, Cindy, additional, Kohler, Annegret, additional, Morin, Emmanuelle, additional, Henrissat, Bernard, additional, Lindquist, Erika, additional, Zimmermann, Sabine D., additional, Girard, Vincent, additional, Kuo, Alan, additional, Grigoriev, Igor V., additional, Martin, Francis, additional, Marmeisse, Roland, additional, and Gay, Gilles, additional

Published
2015
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16. The auxin transport inhibitor 2, 3, 5-triiodobenzoic acid (TIBA) inhibits the stimulation of in vitro lateral root formation and the colonization of the tap-root cortex of Norway spruce (Picea abies) seedlings by the ectomycorrhizal fungus Laccaria bicolor

Author

Karabaghli-Degron, C., Sotta, B., Bonnet, M., Gay, Gilles, Le Tacon, F., Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Ecole Nationale Vétérinaire de Lyon (ENVL)

Subjects
Hartig net formation, indole-3-acetic acid (IAA), [SDV]Life Sciences [q-bio], 5-triiodobenzoic acid (TIBA), Lateral root induction, food and beverages, ectomycorrhizal fungus
Abstract

International audience; Norway spruce (Picea abies (L.) Karst.) seedlings were inoculated with the ectomycorrhizal fungus Laccaria bicolor ((Marie) Orton), strain S238 N, in axenic conditions. The presence of the fungus slowed tap\textendashroot elongation by 26% during the first 15 d after inoculation and then stimulated it by 136%. In addition, it multiplied in vitro lateral root formation by 4.3, the epicotyl growth of the seedlings by 8.4 and the number of needles by 2. These effects were maintained when the fungus was separated from the roots by a cellophane membrane preventing symbiosis establishment, thus suggesting that the fungus acted by non-nutritional effects. We tested the hypothesis that IAA produced by L. bicolor S238 N would be responsible for the stimulation of fungal induced rhizogenesis. We showed in previous work that L. bicolor S238 N can synthesize IAA in pure culture. Exogenous IAA supplies (100 and 500 μm) reproduced the stimulating effect of the fungus on root branching but inhibited root elongation. The presence of 2,3,5-triiodobenzoic acid (TIBA) in the culture medium significantly depressed lateral root formation of inoculated seedlings. As TIBA had no significant effect on IAA released in the medium by L. bicolor S238 N, but counteracted the stimulation of lateral rhizogenesis induced by an exogenous supply of IAA, we suggest that TIBA inhibited the transport of fungal IAA in the root. Furthermore TIBA blocked the colonization of the main root cortex by L. bicolor S238 N and the formation of the Hartig net. These results specified the role of fungal IAA in the stimulation of lateral rhizogenesis and in ectomycorrhizal symbiosis establishment.

Published
2008
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18. Transformation du champignon ectomycorhizien Hebeloma cylindosporum par Agrobacterium tumefaciens

Author

Combier, Jean-Philippe, Melayah, Delphine, Marmeisse, Roland, and Gay, Gilles

Subjects
Agrobacterium tumefaciens, P34 - Biologie du sol, Hebeloma, Transformation génétique
Abstract

Bien qu'Agrobacterium tumefaciens ne soit pas pathogène des champignons, il peut transférer l'ADNT de son plasmide Ti à des cellules fongiques qui l'intègrent dans leur ADN génomique. Cette propriété est à l'origine du récent développement d'une méthode de transformation des espèces fongiques qui présente plusieurs avantages par rapport aux méthodes traditionnelles utilisant des plasmides circulaires ou linéaires. D'une part, elle ne nécessite pas la préparation de protoplastes et d'autre part le mode d'intégration de l'ADN-T dans l'ADN génomique permet de caractériser facilement les séquences génomiques flanquantes. Peu de Basidiomycètes ont pour l'instant été transformés en utilisant cette bactérie. Nous décrivons ici une méthode de transformation génétique d'Hebeloma cylindrosporum, Basidiomycète ectomycorhizien, par A. tumefaciens. Une analyse par PCR et Southern blot a montré que tous les transformants obtenus (treize pour l'instant) ne possèdent qu'une seule copie de l'ADN-T intégrée. Une analyse par TAIL PCR nous a permis d'identifier les sites d'intégration de ces insertions. Cette méthode est actuellement utilisée au laboratoire pour obtenir des mutants non mycorhiziens d'H. cylindrosporum. Les résultats présentés ici montrent que l'identification des gènes inactivés est plus facile que dans le cas de la mutagenèse par insertion de plasmide. (Texte intégral)

Published
2002

27. The dominant Hc.SdhR carboxin-resistance gene of the ectomycorrhizal fungus Hebeloma cylindrosporum as a selectable marker for transformation.

Author

Ngari, Chrisse, Combier, Jean-Philippe, Doré, Jeanne, Marmeisse, Roland, Gay, Gilles, and Melayah, Delphine

Subjects
ECTOMYCORRHIZAL fungi, MYCORRHIZAL fungi, HEBELOMA, GENES, DRUG resistance in microorganisms
Abstract

In an attempt to get a marker gene suitable for genetical transformation of the ectomycorrhizal fungus Hebeloma cylindrosporum, the gene Hc.SdhR that confers carboxin-resistance was isolated from a UV mutant of this fungus. It encodes a mutant allele of the Fe–S subunit of the succinate dehydrogenase gene that carries a single amino acid substitution known to confer carboxin-resistance. This gene was successfully used as the selective marker to transform, via Agrobacterium tumefaciens, monokaryotic and dikaryotic strains of H. cylindrosporum. We also successfully transformed hygromycin-resistant insertional mutants. Transformation yielded mitotically stable carboxin-resistant mycelia. This procedure produced transformants, the growth of which was not affected by 2 μg l−1 carboxin, whereas wild-type strains were unable to grow in the presence of 0.1 μg l−1 of this fungicide. This makes the carboxin-resistance cassette much more discriminating than the hygromycin-resistance one. PCR amplification and Southern blot hybridisation indicated that more than 90% of the tested carboxin-resistant mycelia contained the Hc.SdhR cassette, usually as a single copy. The AGL-1 strain of A. tumefaciens was a much less efficient donor than LBA 1126; the former yielded ca. 0–30% transformation frequency, depending on fungal strain and resistance cassette used, whereas the latter yielded ca. 60–95%. [ABSTRACT FROM AUTHOR]

Published
2009
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31. Agrobacterium tumefaciens-mediated transformation as a tool for insertional mutagenesis in the symbiotic ectomycorrhizal fungus Hebeloma cylindrosporum

Author

Combier, Jean-Philippe, Melayah, Delphine, Raffier, Colette, Gay, Gilles, and Marmeisse, Roland

Subjects
FUNGI, MUTAGENESIS
Abstract

We transformed haploid mycelium of Hebeloma cylindrosporum via Agrobacterium tumefaciens and optimised the procedure to develop a new tool for insertional mutagenesis in this fungus. Southern blot analysis of 83 randomly selected transformants showed that they all contained plasmid inserts. Each of them showed a unique hybridisation pattern, suggesting that integration was random in the fungal genome. Sixty percent of transformants obtained in the presence of bacteria pre-treated with acetosyringone integrated a single transferred DNA copy. Thermal asymmetric interlaced polymerase chain reaction allowed us to recover the left border and the right border junctions in 85% and 15% of transformants analysed, respectively. Results show that A. tumefaciens-mediated transformation may be a powerful tool for insertional mutagenesis in H. cylindrosporum. [Copyright &y& Elsevier]

Published
2003
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32. Isolation and characterization of nitrate reductase deficient mutants of the ectomycorrhizal fungus <em>Hebeloma cylindrosporum</em>.

Author

Marmeisse, Roland, Jargeat, Patricia, Wagner, Françoise, Gay, Gilles, and Debaud, Jean-Claude

Subjects
ECTOMYCORRHIZAS, HEBELOMA, NITROGEN, PLANT nutrition, CLUSTER pine, MYCELIUM
Abstract

To clarify the role of the fungal nitrate assimilation pathway in nitrate reduction by mycorrhizal plants, nitrate reductase (NR)-deficient (NR-) mutants of the ectomvcorrhizal basidiomycete Hebeloma cylindrosporum Romagnesi have been selected. These mutants were produced by u.v. mutagenesis on protoplasts originating from homokaryotic mycelia belonging to complementary mating types of this heterothallic tetrapolar species. Chlorate-resistant mutants were first selected in the presence of different nitrogen (N) sources in the culture medium. Among 1495 chlorate resistant mycelia. 30 failed to grow on nitrate and lacked a detectable NR activity. Growth tests on different N sources suggested that the NR activity of all the different mutants is specifically impaired as a result of mutations in either the gene coding for NR apoprotein or genes controlling the synthesis of the molybdenum cofactor. Furthermore, restoration of NR activity in some of the dikaryons obtained after crosses between the different mutant mycelia suggested that not all the selected mutations mapped in the same gene. Utilization of N on a NH415NO3 medium was studied for two mutant strains and their corresponding wild-type homokaryons. None of the mutants could use nitrate whereas 15N enrichment values indicated that 13 27% of N present in 13-d-old wild-type mycelia originated from nitrate. Apparently, the mutant mycelia do not compensate their inability to use nitrate by a more efficient use of ammonium. These different NR mutants still form mycorrhizas with the habitual host plant, Pinus pinaster (Ait.), making them suitable for study of the contribution of the fungal nitrate assimilation pathway to nitrate assimilation In mycorrhizal plants. [ABSTRACT FROM AUTHOR]

Published
1998
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34. Accuracy of across-environment genome-wide prediction in maize nested association mapping populations.

Author

Guo Z, Tucker DM, Wang D, Basten CJ, Ersoz E, Briggs WH, Lu J, Li M, and Gay G

Subjects
Crosses, Genetic, Genotype, Models, Biological, Multifactorial Inheritance, Phenotype, Plant Leaves chemistry, Plant Leaves genetics, Plant Leaves metabolism, Quantitative Trait Loci, Genome, Plant, Zea mays genetics
Abstract

Most of previous empirical studies with genome-wide prediction were focused on within-environment prediction based on a single-environment (SE) model. In this study, we evaluated accuracy improvements of across-environment prediction by using genetic and residual covariance across correlated environments. Predictions with a multienvironment (ME) model were evaluated for two corn polygenic leaf structure traits, leaf length and leaf width, based on within-population (WP) and across-population (AP) experiments using a large maize nested association mapping data set consisting of 25 populations of recombinant inbred-lines. To make our study more applicable to plant breeding, two cross-validation schemes were used by evaluating accuracies of (CV1) predicting unobserved phenotypes of untested lines and (CV2) predicting unobserved phenotypes of lines that have been evaluated in some environments but not others. We concluded that (1) genome-wide prediction provided greater prediction accuracies than traditional quantitative trait loci-based prediction in both WP and AP and provided more advantages over quantitative trait loci -based prediction for WP than for AP. (2) Prediction accuracy with ME was significantly greater than that attained by SE in CV1 and CV2, and gains with ME over SE were greater in CV2 than in CV1. These gains were also greater in WP than in AP in both CV1 and CV2. (3) Gains with ME over SE attributed to genetic correlation between environments, with little effect from residual correlation. Impacts of marker density on predictions also were investigated in this study.

Published
2013
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