| 1. |
- Felten, Judith, et al.
(author)
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The ectomycorrhizal fungus laccaria bicolor stimulates lateral root formation in poplar and arabidopsis through auxin transport and signaling
- 2009
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In: Plant Physiology. - Rockville : American society of plant biologists. - 0032-0889 .- 1532-2548. ; 151:4, s. 1991-2005
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Journal article (peer-reviewed)abstract
- The early phase of the interaction between tree roots and ectomycorrhizal fungi, prior to symbiosis establishment, is accompanied by a stimulation of lateral root (LR) development. We aimed to identify gene networks that regulate LR development during the early signal exchanges between poplar (Populus tremula x Populus alba) and the ectomycorrhizal fungus Laccaria bicolor with a focus on auxin transport and signaling pathways. Our data demonstrated that increased LR development in poplar and Arabidopsis (Arabidopsis thaliana) interacting with L. bicolor is not dependent on the ability of the plant to form ectomycorrhizae. LR stimulation paralleled an increase in auxin accumulation at root apices. Blocking plant polar auxin transport with 1-naphthylphthalamic acid inhibited LR development and auxin accumulation. An oligoarray-based transcript profile of poplar roots exposed to molecules released by L. bicolor revealed the differential expression of 2,945 genes, including several components of polar auxin transport (PtaPIN and PtaAUX genes), auxin conjugation (PtaGH3 genes), and auxin signaling (PtaIAA genes). Transcripts of PtaPIN9, the homolog of Arabidopsis AtPIN2, and several PtaIAAs accumulated specifically during the early interaction phase. Expression of these rapidly induced genes was repressed by 1-naphthylphthalamic acid. Accordingly, LR stimulation upon contact with L. bicolor in Arabidopsis transgenic plants defective in homologs of these genes was decreased or absent. Furthermore, in Arabidopsis pin2, the root apical auxin increase during contact with the fungus was modified. We propose a model in which fungus-induced auxin accumulation at the root apex stimulates LR formation through a mechanism involving PtaPIN9-dependent auxin redistribution together with PtaIAA-based auxin signaling.
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| 2. |
- Kempf, Emmanuelle, et al.
(author)
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Discrepancies in the use of chemotherapy and artificial nutrition near the end of life for hospitalised patients with metastatic gastric or oesophageal cancer. A countrywide, register-based study
- 2017
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In: European Journal of Cancer. - : Elsevier BV. - 0959-8049 .- 1879-0852. ; 79, s. 31-40
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Journal article (peer-reviewed)abstract
- Aim: To evaluate the frequency and the factors associated with the use of chemotherapy and artificial nutrition near the end of life in hospitalised patients with metastatic oesophageal or gastric cancer.Methods: Nationwide, register-based study, including all hospitalised adults (>= 20 years) who died with metastatic oesophageal or gastric cancer between 2010 and 2013, in France. Chemotherapy and artificial nutrition during the final weeks of life were considered as primary outcomes.Results: A total of 4031 patients with oesophageal cancer and 10,423 patients with gastric cancer were included. While the proportion of patients receiving chemotherapy decreased from 35.9% during the 3rd month before death to 7.9% in the final week (p < 0.001 for trend), the use of artificial nutrition rose from 9.6% to 16.0% of patients. During the last week before death, patients with stomach cancer were more likely to receive chemotherapy (adjusted odds ratio (aOR) = 1.35, 95% CI = 1.17-1.56) but less likely to receive artificial nutrition (aOR = 0.80, 95% CI = 0.73-0.88) than patients with cancer of the oesophagus. The adjusted rates of chemotherapy use during the last week of life varied from 1.6% in rural hospitals to 11.2% in comprehensive cancer centres, while the adjusted probability to receive artificial nutrition varied from 12.1% in private for-profit clinics up to 19.9% in rehabilitation care facilities (p < 0.001).Conclusions: Our study shows that in hospitalised patients with metastatic oesophageal or gastric cancer, the use of chemotherapy decreases while the use of artificial nutrition increases as death approaches. This raises important questions, as clinical guidelines clearly recommend to limit the use of artificial nutrition in contexts of limited life expectancy.
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| 3. |
- Kohler, Annegret, et al.
(author)
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Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists.
- 2015
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In: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:4, s. 176-410
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Journal article (peer-reviewed)abstract
- To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.
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| 4. |
- Morin, Samuel, et al.
(author)
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Pan-European meteorological and snow indicators of climate change impact on ski tourism
- 2021
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In: Climate Services. - : Elsevier. - 2405-8807. ; 22
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Journal article (peer-reviewed)abstract
- Ski tourism plays a major socio-economic role in the snowy and mountainous areas of Europe such as the Alps, the Pyrenees, Nordic Europe, Eastern Europe, Anatolia, etc. Past and future climate change has an impact on the operating conditions of ski resorts, due to their reliance on natural snowfall and favorable conditions for snowmaking. However, there is currently a lack of assessment of past and future operating conditions of ski resorts at the pan-European scale in the context of climate change. The presented work aims at filling this gap, as part of the ”European Tourism” Sectoral Information System (SIS) of the Copernicus Climate Change Services (C3S). The Mountain Tourism Meteorological and Snow Indicators (MTMSI) were co-designed with representatives of the ski tourism industry, including consulting companies. They were derived from statistically adjusted EURO-CORDEX climate projections (multiple GCM/RCM pairs for RCP2.6, RCP4.5 and RCP8.5) using the UERRA 5.5 km resolution surface reanalysis as a reference, used as input to the snow cover model Crocus, with and without accounting for snow management (grooming, snowmaking). Results are generated for 100 m elevation bands for NUTS-3 geographical areas spanning all areas relevant to ski tourism in Europe. This article introduces the underpinning elements for the generation of this product, and illustrates results at the pan-European scale as well as for smaller scale case studies. A dedicated visualization app allows for easy navigation into the multiple dimensions of this dataset, thereby fulfilling the needs of a broad range of users.
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| 5. |
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| 6. |
- Morin, Samuel, et al.
(author)
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The Mountain Component of the Copernicus Climate Change Services - Sectoral Information Service "European Tourism" : Towards Pan-European Analysis and Projections of Natural and Managed Snow Conditions
- 2018
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In: International Snow Science Workshop Proceedings 2018. - : Montana State University Library.
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Conference paper (peer-reviewed)abstract
- Ski tourism plays a major role in European mountain areas such as the Alps, Pyrenees, Scandinavia, Turkey, Eastern European Mountains etc. Meteorological conditions govern the operating conditions of ski resorts, due to their reliance on natural snow fall and favorable conditions for snowmaking. However, there is currently a major lack of assessment of past and future operating conditions of ski resorts at the pan-European scale in the context of climate change. The presented work aims at filling this gap, as part of the ongoing development of « European Tourism » Sectoral Information Service (SIS) of the Copernicus Climate Change Services (C3S). C3S is run by the European Center for Medium-range Weather Forecast (ECMWF) on behalf of the European Commission. Such an endeavor requires combining state-of-the-art meteorological reanalysis with regional climate projections, followed by the application of a snowpack model accounting for grooming and snowmaking. Emphasis will be placed on the workflow making it possible to analyze the data with various levels of aggregation (from daily data to annual scale indicators, to their statistical moments accounting for multiple climate scenarios and lead times), in order to address the needs of various stakeholders, at the European, national, regional and local scales. The data will be made available freely through the Copernicus Data Store in various ways (download of raw data, download or graphics based on post-processed information accounting for user specific needs). It is expected that the data and the tools developed within this project will not only make it possible to analyze the climate sensitivity of ski tourism in Europe as a topical yet academic research question, but would also help third-parties in developing climate services specifically targeting the ski tourism industry in Europe. This contribution introduces the scientific background and general strategy for generating the products, and delivers preliminary information relevant to this upcoming operational service, planned to open to users from 2019 onwards.
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| 7. |
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| 8. |
- Rineau, F., et al.
(author)
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Comparative genomics and expression levels of hydrophobins from eight mycorrhizal genomes
- 2017
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In: Mycorrhiza. - : Springer Science and Business Media LLC. - 0940-6360 .- 1432-1890. ; 27:4, s. 383-396
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Journal article (peer-reviewed)abstract
- Hydrophobins are small secreted proteins that are present as several gene copies in most fungal genomes. Their properties are now well understood: they are amphiphilic and assemble at hydrophilic/hydrophobic interfaces. However, their physiological functions remain largely unexplored, especially within mycorrhizal fungi. In this study, we identified hydrophobin genes and analysed their distribution in eight mycorrhizal genomes. We then measured their expression levels in three different biological conditions (mycorrhizal tissue vs. free-living mycelium, organic vs. mineral growth medium and aerial vs. submerged growth). Results confirmed that the size of the hydrophobin repertoire increased in the terminal orders of the fungal evolutionary tree. Reconciliation analysis predicted that in 41% of the cases, hydrophobins evolved from duplication events. Whatever the treatment and the fungal species, the pattern of expression of hydrophobins followed a reciprocal function, with one gene much more expressed than others from the same repertoire. These most-expressed hydrophobin genes were also among the most expressed of the whole genome, which suggests that they play a role as structural proteins. The fine-tuning of the expression of hydrophobin genes in each condition appeared complex because it differed considerably between species, in a way that could not be explained by simple ecological traits. Hydrophobin gene regulation in mycorrhizal tissue as compared with free-living mycelium, however, was significantly associated with a calculated high exposure of hydrophilic residues.
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