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6. Microhabitat Structure Affects Ground-Dwelling Beetle Communities More than Temperature along an Urbanization Gradient.

Author

Cabon, Valentin, Laurent, Yann, Georges, Romain, Quénol, Hervé, Dubreuil, Vincent, and Bergerot, Benjamin

Subjects
URBAN ecology, URBAN heat islands, GROUND beetles, STAPHYLINIDAE, PUBLIC spaces
Abstract

Urbanization profoundly alters environmental conditions for organisms, particularly through the urban heat island (UHI) effect, which elevates temperatures in city centers. This study examines the influence of urban environmental variables on rove and ground beetle communities. We sampled 36 grasslands in Rennes (northwestern France), yielding 3317 and 505 staphylinid and carabid adult individuals, respectively, belonging to 121 and 60 species, respectively. Staphylinid and carabid communities are not primarily affected by temperature-related variables. Staphylinids, often overlooked in urban ecology, showed species composition variation to be influenced by habitat and temperature, whereas their functional diversity was positively correlated with herbaceous vegetation height only. In contrast, carabid communities exhibited no significant relationship with the tested environmental variables. This study underscores the taxon-dependent nature of ectotherm's responses to thermal environments. Although a further investigation into species-specific traits, and particularly dispersal capacities in staphylinids, is needed to advance our understanding of urbanization's impact, our results indicate that functional diversity in staphylinid assemblages can be favored by locally reducing the mowing frequency or increasing the cutting height within urban green spaces. [ABSTRACT FROM AUTHOR]

Published
2024
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8. Increasing crop heterogeneity enhances multitrophic diversity across agricultural regions

Author

Sirami, Clélia, Gross, Nicolas, Baillod, Aliette Bosem, Bertrand, Colette, Carrié, Romain, Hass, Annika, Henckel, Laura, Miguet, Paul, Vuillot, Carole, Alignier, Audrey, Girard, Jude, Batáry, Péter, Clough, Yann, Violle, Cyrille, Giralt, David, Bota, Gerard, Badenhausser, Isabelle, Lefebvre, Gaëtan, Gauffre, Bertrand, Vialatte, Aude, Calatayud, François, Gil-Tena, Assu, Tischendorf, Lutz, Mitchell, Scott, Lindsay, Kathryn, Georges, Romain, Hilaire, Samuel, Recasens, Jordi, Solé-Senan, Xavier Oriol, Roblen˜o, Irene, Bosch, Jordi, Barrientos, Jose Antonio, Ricarte, Antonio, Marcos-Garcia, Maria Ángeles, Min˜ano, Jesús, Mathevet, Raphaël, Gibon, Annick, Baudry, Jacques, Balent, Gérard, Poulin, Brigitte, Burel, Françoise, Tscharntke, Teja, Bretagnolle, Vincent, Siriwardena, Gavin, Ouin, Annie, Brotons, Lluis, Martin, Jean-Louis, and Fahrig, Lenore

Published
2019

12. First record of Zaprionus tuberculatus (Diptera: Drosophilidae) in mainland France.

Author

Georges, Romain, Yassin, Amir, and Colinet, Hervé

Subjects
*DROSOPHILIDAE, *FIG, *DIPTERA, *FRUIT flies, *DROSOPHILA suzukii, *POPULATION dynamics, *PESTS
Abstract

As most drosophilid species are not considered as primary pest, studies of their communities in natura, with standardized surveys, are relatively sparse. However, Drosophila suzukii and its rapid expansion through the world led to the implementation of many monitoring programs. As part of a research project on D. suzukii, we set up in 2022 an annual fly monitoring in 16 fruits plantations in France to understand population's dynamics of D. suzukii and to broadly survey drosophilid communities. The captures led to the first observation of Zaprionus tuberculatus in mainland France. Over the whole monitoring, we trapped a total of 111 specimens in a fig orchard located in southern France (Salses‐le‐Château), both in fig trees and nearby hedgerow. The first detection of Zaprionus tuberculatus occurred in July 2022 in the hedgerow, and captures continued until January 2023 with an interruption in November and December. In addition, in this orchard we collected overripe figs in September 2023 from which over 20 Z. tuberculatus have emerged in the following 2 weeks, confirming the establishment of a permanent population. The pest status of Z. tuberculatus and its potential risk for agriculture is not yet clear, but the pest behavior of the close‐relative species Zaprionus indianus, especially on figs, should be a warning point for the entry of Z. tuberculatus into the EU and France, as they may have similar polyphagous habit. The pest status and range expansion of Z. tuberculatus should be assessed to estimate risk to fruit's production. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe

Author

Hass, Annika L., Kormann, Urs G., Tscharntke, Teja, Clough, Yann, Baillod, Aliette Bosem, Sirami, Clélia, Fahrig, Lenore, Martin, Jean-Louis, Baudry, Jacques, Bertrand, Colette, Bosch, Jordi, Brotons, Lluís, Burel, Françoise, Georges, Romain, Giralt, David, Marcos-García, María Á., Ricarte, Antonio, Siriwardena, Gavin, and Batáry, Péter

Published
2018

15. Endogeic earthworms facing pesticide residues in agricultural landscapes: bioaccumulation and population risk assessment

Author

Barranger, Audrey, Georges, Romain, Delhomme, Olivier, Millet, Maurice, Lafay, Florent, Vulliet, Emmanuelle, Daniele, Gaëlle, Binet, Françoise, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience

Published
2022

16. Insights into the exposure to pesticide of gamebirds through the food chain in agricultural landscapes, the emblematic earthworm - woodcock model

Author

Barranger, Audrey, Georges, Romain, Gouesbet, Valérie, Martin, Marie-Claire, Le Rest, Kévin, Giroud, Barbara, Vulliet, Emmanuelle, Daniele, Gaëlle, Binet, Françoise, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Office français de la biodiversité (OFB), TRACES - Technologie et Recherche en Analyse Chimique pour l'Environnement et la Santé, Institut des Sciences Analytiques (ISA), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE]Environmental Sciences, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience

Published
2022

18. Macroecological patterns of fruit infestation rates by the invasive fly Drosophila suzukii in the wild reservoir host plant Sambucus nigra.

Author

Ulmer, Romain, Couty, Aude, Eslin, Patrice, Catterou, Manuella, Baliteau, Lucas, Bonis, Anne, Borowiec, Nicolas, Colinet, Hervé, Delbac, Lionel, Dubois, Françoise, Estoup, Arnaud, Froissard, Joris, Gallet‐Moron, Emilie, Gard, Benjamin, Georges, Romain, Gibert, Patricia, Le Goff, Isabelle, Lemauviel‐Lavenant, Servane, Loucougaray, Gregory, and Michelot‐Antalik, Alice

Subjects
DROSOPHILA suzukii, HOST plants, FRUIT flies, WILD plants, FRUIT
Abstract

The invasive pest Drosophila suzukii is a fruit fly native to Asia that infests a wide variety of fruits. Wild plant species are major reservoirs for D. suzukii populations but their infestation rates vary greatly among geographical areas.We aimed at disentangling the relative roles of macroclimatic, landscape and local factors in the rate of D. suzukii infestation of elderberry fruits (Sambucus nigra), a major wild host plant in Europe.We collected elderberry fruits across 215 sites distributed in 13 regions from North to South of France. We counted the number of emerging D. suzukii adults and tested for the effect of macroclimatic, landscape, local biotic and abiotic variables, as well as plant traits using linear mixed models.Site latitude and mean daily maximum temperature since the beginning of the year had respectively the strongest positive and negative effects on mean infestation rates across regions. Infestation rates also increased with forest cover in a 100 m radius around sampling sites.This study shows the importance of taking into account multiple scales and factors, from the fruit characteristics (i.e. maturity) to landscape composition and macroclimatic variables, when studying the interaction between D. suzukii and its host plants. [ABSTRACT FROM AUTHOR]

Published
2022
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19. Macroecological Patterns of Fruit Infestation Rates by the Invasive Fly Drosophila suzukii in the Reservoir Host Plant Sambucus nigra

Author

Ulmer, Romain, Couty, Aude, Eslin, Patrice, Baliteau, Lucas, Bonis, Anne, Borowiec, Nicolas, Colinet, H, Delbac, Lionel, Estoup, Arnaud, Froissard, Joris, Gallet-Moron, Emilie, Gard, Benjamin, Georges, Romain, Gibert, Patricia, Le Goff, Isabelle, Lemauviel-Lavenant, Servanne, Loucougaray, Gregory, Michelot-Antalik, Alice, Odoux, Jean-François, Pincebourde, Sylvain, Rode, Nicolas, Thaon, Marcel, Till-Bottraud, Irène, Chabrerie, Olivier, Ecologie et Dynamique des Systèmes Anthropisés - UMR CNRS 7058 (EDYSAN), Centre National de la Recherche Scientifique (CNRS)-Université de Picardie Jules Verne (UPJV), CPIE des Pays de l'Oise, Laboratoire de Géographie Physique et Environnementale (GEOLAB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Clermont Auvergne (UCA)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Institut Sophia Agrobiotech (ISA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Côte d'Azur (UCA), Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Santé et agroécologie du vignoble (UMR SAVE), Université de Bordeaux (UB)-Institut des Sciences de la Vigne et du Vin (ISVV)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD [France-Sud])-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 de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-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), Ecophysiologie Végétale, Agronomie et Nutritions NCS (EVA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire des EcoSystèmes et des Sociétés en Montagne (UR LESSEM), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire Agronomie et Environnement (LAE), Université de Lorraine (UL)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de recherche sur la biologie de l'insecte UMR7261 (IRBI), Université de Tours-Centre National de la Recherche Scientifique (CNRS), Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS), Centre Permanent d'Initiatives pour l'Environnement (CPIE) des Pays de l’Oise (CPIE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - 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), Ctifl - Centre de Balandran (Ctifl - Centre de Balandran), Centre Technique Interprofessionnel des Fruits et Légumes (CTIFL), Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), and Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.EE]Life Sciences [q-bio]/Ecology, environment, spotted wing drosophila, pest, biological invasion, [SDV.BID]Life Sciences [q-bio]/Biodiversity, wild plants, landscape, exotic species, macroclimate
Abstract

International audience; The invasive pest Drosophila suzukii (Matsumura, 1931) is a fruit fly native to Asia that infests a wide variety of cultivated and wild fruits, causing important damages on agricultural production. Wild plant species are major reservoirs for D. suzukii populations but their infestation rates varies greatly among geographical areas. This heterogeneity could partly be caused by a heterogeneity of environmental conditions acting across different spatial scales. This study aimed to disentangle the relative roles of macroclimatic, landscape and local factors that could affect the success of D. suzukii infestation of elderberry fruits (Sambucus nigra), a major and widespread host plant along climatic gradients. We collected elderberry fruits and measured vegetative and reproductive life traits of the plants in 215 sites distributed in 13 regions from North to South France during summer 2020. We counted the number of D. suzukii emerging from sampled fruits and tested for an effect of macroclimatic, landscape and local abiotic and biotic variables, as well as plant traits using linear mixed models with region as random factor. Latitude and mean maximum temperature had respectively the strongest positive and negative effects on mean infestation rates across regions (R = 0.761, p = 0.003 and R = −0.758, p = 0.004). Mixed models also showed that fruit infestation rate increased with the number of mature fruits within corymb and with forest cover in a 100 m radius around sampling sites and decreased with mean maximum temperature. The latitudinal and climatic clines in infestation rates suggests that D. suzukii population size might vary greatly among geographic regions. Our results also suggest that population sizes are larger in the presence of semi-natural habitats such as forest patches in the surrounding landscape. Our work contributes to enhancing our understanding of D. suzukii ecology, which is important to predict how infestation rates might change in the context of global climatic changes.

Published
2021

20. The Role of Hydrographic Mapping in the Study of Emerging Aquatic Insects on the Landscape Scale.

Author

Gerber, Rémi, Bergerot, Benjamin, Georges, Romain, Roussel, Jean-Marc, and Piscart, Christophe

Subjects
AQUATIC insects, SCALE insects, STONEFLIES, BODIES of water, CADDISFLIES
Abstract

Emerging aquatic insects constitute one of the main biological flows connecting aquatic and terrestrial ecosystems. In a landscape, there are many sources of emergence, which vary in space and time. Thus, they must be clearly defined when studying the inland dispersal of aquatic insects. In this study, we defined five types of hydrographic networks (including or not including ponds and ditches) on the basis of cartographic data of varying degrees of detail (from OpenStreetMap to field map) in order to explain the abundance of aquatic insects. We sampled Ephemeroptera, Plecoptera, Trichoptera, and Megaloptera (ETPM) with 64 sticky traps homogeneously covering a 75 ha agricultural landscape. The abundance of aquatic insects is logically better explained by the hydrographic networks recorded directly in the field than by the reference network, which is incomplete (OpenStreetMap). The results show that, depending on the sampling period, not all water bodies in the landscape are necessarily sources of emergence. To our knowledge, the issue of defining the sources of emerging aquatic insects has never been raised. Based on a practical example, this short note shows that, by refining the hydrographic network to better match the sources of emergence, the explanatory power of inland aquatic insect abundance can be greatly improved. [ABSTRACT FROM AUTHOR]

Published
2022
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22. La biodiversité microbienne et ingénieure des sols en contexte périurbain : effets combinés des historiques culturaux et des modes de gestion

Author

Barranger, Audrey, Capiaux, Hervé, Georges, Romain, Jean Soro, Liliane, Le Guern, Cécile, Lebeau, Thierry, Binet, Françoise, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Polymères, biopolymères, membranes (PBM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Association Francophone d’Ecologie Microbienne, Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

23. Effects of connectivity on seed dispersal patterns in hedgerows.

Author

Mony, Cendrine, Landais, Quentin, Georges, Romain, Butet, Alain, Burel, Françoise, Jambon, Olivier, Gouesbet, Valérie, and Ernoult, Aude

Abstract

Question: Habitat isolation is a major driver of biodiversity because it affects dispersal among local communities, especially for plants. Corridors are supposed to facilitate the movement of organisms and hence their effective dispersal, thereby increasing biodiversity. Hedgerows provide favorable habitats for forest plant establishment, but their role in dispersal among forest patches is still unknown. In addition, seeds can be more predated within hedgerows because animal movement is also encouraged by these corridors. We aimed to answer the question: Are plant dispersal and seed removal by animals in connected hedgerows compared with unconnected hedgerows promoted for forest plant species? Location: Long‐term ecological site “Zone Atelier Armorique”, western France (ca. 150 km2). Methods: We analyzed seed dispersal along two pathways in 16 woodlots: connected (least‐cost pathways, i.e., optimal corridors); and unconnected high cost pathways (absence of corridor). Using a trap study, we first quantified seed rain and analyzed seed composition after trapped seeds were germinated in the greenhouse. At the same sampling points, we then analyzed the rate at which two different sized seeds were removed from seed baits by animals. Results: Our results revealed no difference in the number of trapped seeds in connected and unconnected pathways, but did reveal a difference in the number and richness of viable seeds, with corridors having a positive impact. In the predation experiment, the rate of removal of small seeds was higher in connected pathways than in unconnected pathways. Conclusion: Connectivity enhanced the dispersal of viable forest plant species but also the predation of small seeds, which possibly played a role in their subsequent dispersal. This work highlighted the effect of connectivity on seed dynamics within hedgerows and improves our understanding of the role of hedgerows as stepping‐stones for seed dispersal among forest patches.Landscape connectivity influenced seed dynamics within hedgerows. It enhanced the dispersal of viable forest plant species in hedgerows but also increased the predation of small seeds, which possibly played a role in their subsequent dispersal. This work highlighted the role of hedgerows as stepping stones for seed dispersal among forest patches.. [ABSTRACT FROM AUTHOR]

Published
2022
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24. The role of landscape heterogeneity for biodiversity in agricultural landscapes

Author

Aviron, Stéphanie, Duflot, Rémi, Georges, Romain, Alignier, Audrey, Baudry, Jacques, Burel, Françoise, Ernoult, Aude, ProdInra, Migration, Biodiversité agroécologie et aménagement du paysage (UMR BAGAP), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, 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)-Ecole supérieure d'Agricultures d'Angers (ESA), Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST-Ecole supérieure d'Agricultures d'Angers (ESA), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

25. Least‐cost path analysis for urban greenways planning: A test with moths and birds across two habitats and two cities.

Author

Balbi, Manon, Croci, Solène, Petit, Eric J., Butet, Alain, Georges, Romain, Madec, Luc, Caudal, Jean‐Pierre, Ernoult, Aude, and Corley, Juan

Subjects
URBAN landscape architecture, URBAN planning, PATH analysis (Statistics), SCIENTIFIC literature, CORRIDORS (Ecology), MOTHS
Abstract

One of the major planning tools to respond to urban landscape fragmentation is the development of ecological corridors, that is, interconnected networks of urban green and blue spaces. Least‐cost paths (LCP) appear to be an easy and appropriate resistance‐based modelling method to respond to urban planners' needs. However, the ecological validation of urban corridors using LCP is rarely performed and needs to be generalized to different species, habitats and cities.We developed an experimental design to test the efficiency of LCP predictions to detect highly connecting landscape contexts that facilitate individual movements compared to movements in less connecting landscape contexts. We deliberately assigned LCP analysis parameters based on the scientific literature and expert knowledge to test a method potentially easy to use for urban stakeholders. To extend the validation, we applied our LCP model to two biological taxa with different habitat requirements: grassland‐dwelling moths and forest‐dwelling passerines, and to two medium‐sized cities.We used mark–release–recapture (MRR) methods for moths and playback recall protocols for passerines to compare the patterns of individual movement between two contrasted connectivity contexts determined by the presence and absence of modelled LCPs. MRR protocol estimated movement rates between herbaceous patches and the two contrasted connectivity contexts. Playback recall protocol consisted in attracting individuals from wooded patches to the two contrasted connectivity contexts. A movement was considered facilitated, when displacement was rapidly engaged and individuals moved a long distance from their wooded patch.Moth and passerine movement patterns differed between the two connectivity contexts: moth recapture rates were higher in highly connecting contexts than in less connecting contexts. For passerine birds, responses to playback recalls were faster and movement distance longer in highly connecting contexts. All results support the hypothesis that both taxa were more prone to move in corridors modelled by LCP.Synthesis and applications. The convergence of the results for different biological models and across cities strengthens the relevance of LCP analysis for planning urban greenways and provides guidelines for landscape planners in the development of these corridors to favour the movement and survival of multiple urban species. [ABSTRACT FROM AUTHOR]

Published
2021
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26. Ground predators benefits more from semi-natural than natural habitats under harsh climatic conditions

Author

Damien, Maxime, Le Lann, Cécile, Hassan, Diab Al, Jambon, Olivier, Georges, Romain, Desneux, Nicolas, Baaren, Joan van, Briand, Valerie, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Institut Sophia Agrobiotech [Sophia Antipolis] (ISA), Institut National de la Recherche Agronomique (INRA)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Ecological Society of America, Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institut Sophia Agrobiotech (ISA), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut National de la Recherche Agronomique (INRA), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

27. Effects of amount of semi-natural habitats and crop mosaic heterogeneity on generalist predator communities (Araenae and Carabidae) and biological control potential

Author

Bertrand, Colette, Georges, Romain, Baudry, Jacques, Burel, Françoise, SAD Paysage (SAD Paysage), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), ANR-11-EBID-0004, ProdInra, Archive Ouverte, ERA-Net BiodivERsA - European Network on Farmland Heterogeneity, Biodiversity and Ecosystem Services - - FarmLand2011 - ANR-11-EBID-0004 - BiodivERsA - VALID, Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), ANR-11-EBID-0004,FarmLand,European Network on Farmland Heterogeneity, Biodiversity and Ecosystem Services(2011), 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), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Carabid beetles and spiders are important generalist predators which may generate an effective control of pest populations. However, to maintain or promote them, it is necessary to better understand the factors that may influence predator communities and predation rates. Previous work has demonstrated that agricultural landscapes which contain significant areas of semi-natural habitats support higher biodiversity and better ecosystem services. But little is known on the effects of the heterogeneity of the cropped area itself. In this study, we investigated the relative and interactive effects of crop heterogeneity (crop composition and configuration) and amount of semi-natural habitats. Within the European FarmLand project (www.farmland-biodiversity.org), we worked in six agricultural regions spanning across western Europe, and differing in terms of landscape complexity : Göttingen (Germany), Armorique, Plaine et Val de Sèvre, Coteaux de Gascogne and Camargue (France), and Lleida (Catalonia, Spain). In each region, carabids and spiders were sampled using pitfall traps along independent gradients in crop composition (crop diversity) and crop configuration (crop mean size), and biological control potential was estimated by recording the removal rate of experimentally added aphids. Agricultural landscapes with more heterogeneous croplands have higher biodiversity and biological control potential, but these effects are modulated by the regional context, and in particular on the amount of semi-natural habitats.

Published
2015

28. Effects of spatial and temporal heterogeneity of agricultural landscapes on carabid beetles assemblages (Coleoptera : Carabidae)

Author

Bertrand, Colette, Baudry, Jacques, Georges, Romain, Burel, Françoise, SAD Paysage (SAD Paysage), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), 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), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), and ProdInra, Archive Ouverte

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, crop mosaic, carabid beetles, landscape heterogeneity, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract

International audience; Previous work has demonstrated that landscapes which contain significant areas of semi-natural habitats support higher biodiversity and better ecosystem services. However, in agricultural landscapes the effects of the cropped area itself are often disregarded, despite the fact that the cultivated mosaic can be highly heterogeneous in space and time. In this study, we investigated the relative effects of the spatial and temporal heterogeneity of the crop mosaic on carabid beetles assemblages in agricultural landscapes of Brittany, western France. Spatial heterogeneity is characterized by the crop composition and configuration of the sampling year, while temporal heterogeneity induced by crop sequences is defined by the rate of crop rotation and the changes in crop composition over the last five years. We assume that croplands spatially heterogeneous should provide resources for more different species, and benefit to species that use more than one crop field type. On the other hand, crop's temporal heterogeneity should benefit species adapted to open and dynamic environments, which could increase carabid beetle abundances in sampled fields. Within the European FarmLand project (www.farmland-biodiversity.org), carabids were sampled using pitfall traps in 40 winter wheat fields, distributed along gradients in crop composition, crop configuration, and crop dynamic. The results show that both spatial and temporal heterogeneity have an influence on the structure and composition of carabid beetles assemblages, affecting essentially the open ground specialists adapted to dynamic environments. Changes in crop diversity over the last five years increase carabid abundances but decrease the evenness of the community; and crop diversity of the sampling year has a positive impact on the diversity of the community. However, these two levels of heterogeneity seems to affect the species differently according to their ecological traits. Species with high dispersal abilities are affected by spatial heterogeneity, while less mobile species are only influenced by crop dynamic.

Published
2014

29. TOX and TOX2 transcription factors cooperate with NR4A transcription factors to impose CD8+ T cell exhaustion.

Author

Hyungseok Seo, Chen, Joyce, González-Avalos, Edahí, Samaniego-Castruita, Daniela, Das, Arundhoti, Wang, Yueqiang H., López-Moyado, Isaac F., Georges, Romain O., Wade Zhang, Onodera, Atsushi, Cheng-Jang Wu, Li-Fan Lu, Hogan, Patrick G., Bhandoola, Avinash, and Rao, Anjana

Subjects
T cells, TRANSCRIPTION factors, NUCLEAR receptors (Biochemistry), CHIMERIC antigen receptors, GENE regulatory networks
Abstract

T cells expressing chimeric antigen receptors (CAR T cells) have shown impressive therapeutic efficacy against leukemias and lymphomas. However, they have not been as effective against solid tumors because they become hyporesponsive ("exhausted" or "dysfunctional") within the tumor microenvironment, with decreased cytokine production and increased expression of several inhibitory surface receptors. Here we define a transcriptional network that mediates CD8+ T cell exhaustion. We show that the high-mobility group (HMG)-box transcription factors TOX and TOX2, as well as members of the NR4A family of nuclear receptors, are targets of the calcium/calcineurin-regulated transcription factor NFAT, even in the absence of its partner AP-1 (FOS-JUN). Using a previously established CAR T cell model, we show that TOX and TOX2 are highly induced in CD8+ CAR+ PD-1high TIM3high ("exhausted") tumor-infiltrating lymphocytes (CAR TILs), and CAR TILs deficient in both TOX and TOX2 (Tox DKO) are more effective than wild-type (WT), TOX-deficient, or TOX2-deficient CAR TILs in suppressing tumor growth and prolonging survival of tumor-bearing mice. Like NR4A-deficient CAR TILs, Tox DKO CAR TILs show increased cytokine expression, decreased expression of inhibitory receptors, and increased accessibility of regions enriched for motifs that bind activation- associated nuclear factor êB (NFêB) and basic region-leucine zipper (bZIP) transcription factors. These data indicate that Tox and Nr4a transcription factors are critical for the transcriptional program of CD8+ T cell exhaustion downstream of NFAT. We provide evidence for positive regulation of NR4A by TOX and of TOX by NR4A, and suggest that disruption of TOX and NR4A expression or activity could be promising strategies for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Published
2019
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30. Agricultural landscape and biodiversity: Effects of landscape heterogeneity on carabid beetles and plants functional diversity in agricultural area

Author

Duflot, Rémi, Georges, Romain, Aviron, Stéphanie, Ernoult, Aude, Burel, Francoise, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), SAD Paysage (SAD Paysage), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, British Ecological Society, Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), 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), Briand, Valerie, Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2012

31. Ecologie du paysage et écologie végétale

Author

Burel, Françoise, Ernoult, Aude, Gil-Tena, Assu, Favre-Bac, Lisa, Mony, Cendrine, Duflot, Rémi, Georges, Romain, Baudry, Jacques, Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), SAD Paysage (SAD Paysage), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Université de Rennes (UR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), AGROCAMPUS OUEST, 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 de la Recherche Agronomique (INRA), and Briand, Valerie

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2012

32. Tet proteins influence the balance between neuroectodermal and mesodermal fate choice by inhibiting Wnt signaling.

Author

Xiang Li, Xiaojing Yue, Pastor, William A., Lizhu Lin, Georges, Romain, Chavez, Lukas, Evans, Sylvia M., and Rao, Anjana

Subjects
PROTEIN analysis, EMBRYONIC stem cells, CHROMOSOMAL translocation, WNT signal transduction, MESODERM, DEMETHYLATION, METHYLCYTOSINE
Abstract

TET-family dioxygenases catalyze conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and oxidized methylcytosines in DNA. Here, we show that mouse embryonic stem cells (mESCs), either lacking Tet3 alone or with triple deficiency of Tet1/2/3, displayed impaired adoption of neural cell fate and concomitantly skewed toward cardiac mesodermal fate. Conversely, ectopic expression of Tet3 enhanced neural differentiation and limited cardiac mesoderm specification. Genome-wide analyses showed that Tet3 mediates cell-fate decisions by inhibiting Wnt signaling, partly through promoter demethylation and transcriptional activation of the Wnt inhibitor secreted frizzled-related protein 4 (Sfrp4). Tet1/2/3-deficient embryos (embryonic day 8.0-8.5) showed hyperactivated Wnt signaling, as well as aberrant differentiation of bipotent neuromesodermal progenitors (NMPs) into mesoderm at the expense of neuroectoderm. Our data demonstrate a key role for TET proteins in modulating Wnt signaling and establishing the proper balance between neural and mesodermal cell fate determination in mouse embryos and ESCs. [ABSTRACT FROM AUTHOR]

Published
2016
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33. Novel Exons in the Tbx5 Gene Locus Generate Protein Isoforms with Distinct Expression Domains and Function.

Author

Yamak, Abir, Georges, Romain O., Sheikh-Hassani, Massomeh, Morin, Martin, Komati, Hiba, and Nemer, Mona

Subjects
*EXONS (Genetics), *HOLT-Oram syndrome, *MULTIPLE human abnormalities, *TRANSCRIPTION factors, *HEART physiology, *ALTERNATIVE RNA splicing, *GENETICS, *PHYSIOLOGY
Abstract

TBX5 is the gene mutated in Holt-Oram syndrome, an autosomal dominant disorder with complex heart and limb deformities. Its protein product is a member of the T-box family of transcription factors and an evolutionarily conserved dosage-sensitive regulator of heart and limb development. Understanding TBX5 regulation is therefore of paramount importance. Here we uncover the existence of novel exons and provide evidence that TBX5 activity may be extensively regulated through alternative splicing to produce protein isoforms with differing N- and C-terminal domains. These isoforms are also present in human heart, indicative of an evolutionarily conserved regulatory mechanism. The newly identified isoforms have different transcriptional properties and can antagonize TBX5a target gene activation. Droplet Digital PCR as well as immunohistochemistry with isoform-specific antibodies reveal differential as well as overlapping expression domains. In particular, we find that the predominant isoform in skeletal myoblasts is Tbx5c, and we show that it is dramatically up-regulated in differentiating myotubes and is essential for myotube formation. Mechanistically, TBX5c antagonizes TBX5a activation of pro-proliferative signals such as IGF-1, FGF-10, and BMP4. The results provide new insight into Tbx5 regulation and function that will further our understanding of its role in health and disease. The finding of new exons in the Tbx5 locus may also be relevant to mutational screening especially in the 30% of Holt-Oram syndrome patients with no mutations in the known TBX5a exons. [ABSTRACT FROM AUTHOR]

Published
2015
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34. Could Behaviour and Not Physiological Thermal Tolerance Determine Winter Survival of Aphids in Cereal Fields?

Author

Alford, Lucy, Andrade, Thiago Oliveira, Georges, Romain, Burel, Françoise, and van Baaren, Joan

Subjects
THERMAL tolerance (Physiology), APHIDS, GRAIN genetics, CLIMATE change, RHOPALOSIPHUM padi, COLD-blooded animals
Abstract

Traits of physiological thermotolerance are commonly measured in the laboratory as predictors of the field success of ectotherms at unfavourable temperatures (e.g. during harsh winters, heatwaves, or under conditions of predicted global warming). Due to being more complicated to measure, behavioural thermoregulation is less commonly studied, although both physiology and behaviour interact to explain the survival of ectotherms. The aphids Metopolophium dirhodum, Rhopalosiphum padi and Sitobion avenae are commercially important pests of temperate cereal crops. Although coexisting, these species markedly differ in winter success, with R. padi being the most abundant species during cold winters, followed by S. avenae and lastly M. dirhodum. To better understand the thermal physiology and behavioural factors contributing to differential winter success, the lethal temperature (physiological thermotolerance) and the behaviour of aphids in a declining temperature regime (behavioural thermotolerance) of these three species were investigated. Physiological thermotolerance significantly differed between the three species, with R. padi consistently the least cold tolerant and S. avenae the most cold tolerant. However, although the least cold tolerant of the study species, significantly more R. padi remained attached to the host plant at extreme sub-zero temperatures than S. avenae and M. dirhodum. Given the success of anholocyclic R. padi in harsh winters compared to its anholocyclic counterparts, this study illustrates that behavioural differences could be more important than physiological thermotolerance in explaining resistance to extreme temperatures. Furthermore it highlights that there is a danger to studying physiological thermotolerance in isolation when ascertaining risks of ectotherm invasions, the establishment potential of exotic species in glasshouses, or predicting species impacts under climate change scenarios. [ABSTRACT FROM AUTHOR]

Published
2014
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35. Landscape heterogeneity as an ecological filter of species traits.

Author

Duflot, Rémi, Georges, Romain, Ernoult, Aude, Aviron, Stéphanie, and Burel, Françoise

Subjects
*LANDSCAPE ecology, *HABITATS, *PLANT conservation, *PLANT communities, *BIODIVERSITY, *AGRICULTURE
Abstract

Abstract: Landscape heterogeneity is a major driver of biodiversity in agricultural areas and represents an important parameter in conservation strategies. However, most landscape ecology studies measure gamma diversity of a single habitat type, despite the assessment of multiple habitats at a landscape scale being more appropriate. This study aimed to determine the effects of landscape composition and spatial configuration on life-history trait distribution in carabid beetle and herbaceous plant communities. Here, we assessed the gamma diversity of carabid beetles and plants by sampling three dominant habitats (woody habitats, grasslands and crops) across 20 landscapes in western France. RLQ and Fourth Corner three-table analyses were used to assess the association of dispersal, phenology, reproduction and trophic level traits with landscape characteristics. Landscape composition and configuration were both significant in explaining functional composition. Carabid beetles and plants showed similar response regarding phenology, i.e. open landscapes were associated with earlier breeding species. Carabid beetle dispersal traits exhibited the strongest relationship with landscape structure; for instance, large and apterous species preferentially inhabited woody landscapes, whereas small and macropterous species preferentially inhabited open landscapes. Heavy seeded plant species dominated in intensified agricultural landscapes (high % crops), possibly due to the removal of weeds (which are usually lightweight seeded species). The results of this study emphasise the roles of landscape composition and configuration as ecological filters and the importance of preserving a range of landscape types to maintain functional biodiversity at regional scales. [Copyright &y& Elsevier]

Published
2014
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36. Tbx20 dose-dependently regulates transcription factor networks required for mouse heart and motoneuron development.

Author

Takeuchi, Jun K., Mileikovskaia, Maria, Koshiba-Takeuchi, Kazuko, Heidt, Analeah B., Mori, Alessandro D., Arruda, Eric P., Gertsenstein, Marina, Georges, Romain, Davidson, Lorinda, Rong Mo, Chi-chung Hui, Henkelman, R. Mark, Nemer, Mona, Black, Brian L., Nagy, Andras, and Bruneau, Benoit G.

Subjects
DEVELOPMENTAL biology, TRANSCRIPTION factors, EMBRYONIC stem cells, STEM cells, BIOCHEMISTRY, GENE expression, GENETIC regulation
Abstract

To elucidate the function of the T-box transcription factor Tbx20 in mammalian development, we generated a graded loss-of-function series by transgenic RNA interference in entirely embryonic stem cell-derived mouse embryos. Complete Tbx20 knockdown resulted in defects in heart formation, including hypoplasia of the outflow tract and right ventricle, which derive from the anterior heart field (AHF), and decreased expression of Nkx2-5 and Mef2c, transcription factors required for AHF formation. A mild knockdown led to persistent truncus arteriosus (unseptated outflow tract) and hypoplastic right ventricle, entities similar to human congenital heart defects, and demonstrated a critical requirement for Tbx20 in valve formation. Finally, an intermediate knockdown revealed a role for Tbx20 in motoneuron development, specifically in the regulation of the transcription factors Isl2 and Hb9, which are important for terminal differentiation of motoneurons. Tbx20 could activate promoters/enhancers of several genes in cultured cells, including the Mef2c AHF enhancer and the Nkx2-5 cardiac enhancer. The Mef2c AHF enhancer relies on Isl1- and Gata-binding sites. We identified a similar Isl1 binding site in the Nkx2-5 AHF enhancer, which in transgenic mouse embryos was essential for activity in a large part of the heart, including the outflow tract. Tbx20 synergized with Isl1 and Gata4 to activate both the Mef2c and Nkx2-5 enhancers, thus providing a unifying mechanism for gene activation by Tbx20 in the AHF. We conclude that Tbx20 is positioned at a critical node in transcription factor networks required for heart and motoneuron development where it dose-dependently regulates gene expression. [ABSTRACT FROM AUTHOR]

Published
2005
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38. Flowering cover crops in winter increase pest control but not trophic link diversity.

Author

Damien, Maxime, Le Lann, Cécile, Desneux, Nicolas, Alford, Lucy, Al Hassan, Diab, Georges, Romain, and Van Baaren, Joan

Subjects
*COVER crops, *PEST control, *PLANT diversity, *FOOD chains, *GLOBAL environmental change
Abstract

In agrosystems, the increase in non-crop plant diversity by habitat management in or around arable fields contributes to improved Conservation Biological Control. During winter, plant flower are often used as monospecific ground cover and are expected to die before flowering as a result of recurrent frost events. Decreases in minimal temperature due to climate change offers new possibilities for plants used in such sown cover crops to mature and flowers. Changes in plant phenology thus constitute an important environmental change with expected consequences for ecosystem functioning, such as biological control. In Brittany, where winter agricultural landscape is dominated by a mosaic of cereal and sown cover crops, we assessed the consequences of mustard ( Synapis alba ) flowering cover crops (MFCC) on aphid parasitism and food web structure in plots adjoining cereal crops, in contrast to plots close to spontaneous non-crop plants (SNCP) of the same field. Overall, aphid parasitism rate at the field scale was strong (60–70%), being 13% higher adjacent to the MFCC than closer to SNCP. In addition, there was no change in food web structure between the two distinct zones, enabling us to hypothesize that MFCC mostly constituted an alimentary patch. The positive effect on parasitism rate was significant but weak, as floral nectar of mustard is known to be of poor quality for parasitoids. Results highlight the potential advantages of adapting practices in response to actual changes in agrosystems. Increase floral diversity in sown cover crops could constitute a complementary method in management programs, by providing more alternative food resources, alternative hosts, and climatic refuge to enhance the Conservation Biological Control of parasitoid populations. [ABSTRACT FROM AUTHOR]

Published
2017
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39. TOX and TOX2 transcription factors cooperate with NR4A transcription factors to impose CD8 + T cell exhaustion.

Author

Seo H, Chen J, González-Avalos E, Samaniego-Castruita D, Das A, Wang YH, López-Moyado IF, Georges RO, Zhang W, Onodera A, Wu CJ, Lu LF, Hogan PG, Bhandoola A, and Rao A

Subjects
Animals, Immunotherapy, Lymphocytes, Tumor-Infiltrating immunology, Mice, Mice, Inbred C57BL, Neoplasms immunology, Neoplasms metabolism, Neoplasms therapy, Protein Binding, RNA, Messenger genetics, Transcription Factors genetics, Tumor Microenvironment, CD8-Positive T-Lymphocytes immunology, Lymphocyte Depletion, Transcription Factors metabolism
Abstract

T cells expressing chimeric antigen receptors (CAR T cells) have shown impressive therapeutic efficacy against leukemias and lymphomas. However, they have not been as effective against solid tumors because they become hyporesponsive ("exhausted" or "dysfunctional") within the tumor microenvironment, with decreased cytokine production and increased expression of several inhibitory surface receptors. Here we define a transcriptional network that mediates CD8 + T cell exhaustion. We show that the high-mobility group (HMG)-box transcription factors TOX and TOX2, as well as members of the NR4A family of nuclear receptors, are targets of the calcium/calcineurin-regulated transcription factor NFAT, even in the absence of its partner AP-1 (FOS-JUN). Using a previously established CAR T cell model, we show that TOX and TOX2 are highly induced in CD8 + CAR + PD-1 high TIM3 high ("exhausted") tumor-infiltrating lymphocytes (CAR TILs), and CAR TILs deficient in both TOX and TOX2 ( Tox DKO) are more effective than wild-type (WT), TOX-deficient, or TOX2-deficient CAR TILs in suppressing tumor growth and prolonging survival of tumor-bearing mice. Like NR4A-deficient CAR TILs, Tox DKO CAR TILs show increased cytokine expression, decreased expression of inhibitory receptors, and increased accessibility of regions enriched for motifs that bind activation-associated nuclear factor κB (NFκB) and basic region-leucine zipper (bZIP) transcription factors. These data indicate that Tox and Nr4a transcription factors are critical for the transcriptional program of CD8 + T cell exhaustion downstream of NFAT. We provide evidence for positive regulation of NR4A by TOX and of TOX by NR4A, and suggest that disruption of TOX and NR4A expression or activity could be promising strategies for cancer immunotherapy., Competing Interests: Conflict of interest statement: The La Jolla Institute of Immunology has a pending patent, PCT/US2018/062354, covering the use and production of engineered immune cells to disrupt NFAT-AP1 pathway transcription factors, including TOX and NR4A family members, with H.S., J.C., and A.R. listed as inventors.

Published
2019
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