Auteurs, date et publication :
Auteurs Alexandru Milcu , Ruben Puga-Freitas , Aaron M. Ellison , Manuel Blouin , Stefan Scheu , Grégoire T. Freschet , Laura Rose , Sebastien Barot , Simone Cesarz , Nico Eisenhauer , Thomas Girin , Davide Assandri , Michael Bonkowski , Nina Buchmann , Olaf Butenschoen , Sebastien Devidal , Gerd Gleixner , Arthur Gessler , Agnès Gigon , Anna Greiner
Publication : Nature Ecology & Evolution
Date : 2025
Volume : 2
Issue : 2
Pages : 279-287
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSRésumé
Pontoscolex corethrurus is a well-known invasive earthworm in tropical zone which is believed to have originated from the Guayana Shield in South America and was described as parthenogenetic. A recent phylogenetic study revealed four cryptic species in the P. corethrurus complex (L1, L2, L3 and L4), among them L1 was particularly widespread and was proposed as P. corethrurus sensu stricto. Here, our aims were to investigate the genetic variation of P. corethrurus L1 in its presumed native and introduced ranges and to examine its reproductive strategy. An extensive dataset of 478 cytochrome oxidase I gene (COI) sequences, obtained in specimens sampled all around the world, revealed a weak COI haplotype diversity with one major haplotype (H1) present in 76% of the specimens. Analyses of the genetic variation of 12 L1 populations were done using both nuclear (226 AFLP profiles) and mitochondrial (269 COI sequences) genetic information. The high AFLP genotype diversity at the worldwide scale and the fact that no genotype was shared among populations, allowed to reject the ‘super-clone’ invasion hypothesis. Moreover, a similar level of mean genetic diversity indices were observed between the introduced and native ranges, a pattern explained by a history of multiple introductions of specimens from different parts of the world. At last, occurrence of identical AFLPs genotypes (i.e. clones) in several population confirmed asexual reproduction, but recombination was also revealed by gametic equilibrium analysis in some populations suggesting that P. corethrurus L1 may have a mixed reproductive strategy.
Auteurs, date et publication :
Auteurs S. Taheri , T. Decaëns , L. Cunha , G. G. Brown , E. Da Silva , M. L. C. Bartz , D. Baretta , L. Dupont
Publication : Biological Invasions
Date : 2025
Volume : 22
Issue : 8
Pages : 2545-2557
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs L Dupont , T Decaëns , E Lapied , V Chassany , R Marichal , Florence Dubs , M Maillot , V Roy
Publication : European Journal of Soil Biology
Date : 2025
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs Marie‐Catherine Boisselier‐Dubayle , Raphaël Leblois , Sarah Samadi , Josie Lambourdière , Corinne Sarthou
Publication : Ecography
Date : 2025
Volume : 33
Issue : 1
Pages : 175-184
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs Marta Gallardo Ruiz , Jean-François Le Galliard , Thomas Tully
Publication : Pedobiologia
Date : 2025
Volume : 61
Pages : 33-41
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSRésumé
Eutrophication is a widespread environmental change that usually reduces the stabilizing effect of plant diversity on productivity in local communities. Whether this effect is scale dependent remains to be elucidated. Here, we determine the relationship between plant diversity and temporal stability of productivity for 243 plant communities from 42 grasslands across the globe and quantify the effect of chronic fertilization on these relationships. Unfertilized local communities with more plant species exhibit greater asynchronous dynamics among species in response to natural environmental fluctuations, resulting in greater local stability (alpha stability). Moreover, neighborhood communities that have greater spatial variation in plant species composition within sites (higher beta diversity) have greater spatial asynchrony of productivity among communities, resulting in greater stability at the larger scale (gamma stability). Importantly, fertilization consistently weakens the contribution of plant diversity to both of these stabilizing mechanisms, thus diminishing the positive effect of biodiversity on stability at differing spatial scales. Our findings suggest that preserving grassland functional stability requires conservation of plant diversity within and among ecological communities.
Auteurs, date et publication :
Auteurs Yann Hautier , Pengfei Zhang , Michel Loreau , Kevin R. Wilcox , Eric W. Seabloom , Elizabeth T. Borer , Jarrett E. K. Byrnes , Sally E. Koerner , Kimberly J. Komatsu , Jonathan S. Lefcheck , Andy Hector , Peter B. Adler , Juan Alberti , Carlos A. Arnillas , Jonathan D. Bakker , Lars A. Brudvig , Miguel N. Bugalho , Marc Cadotte , Maria C. Caldeira , Oliver Carroll
Publication : Nature Communications
Date : 2020
Volume : 11
Issue : 1
Pages : 5375
Catégorie(s)
#CEREEP #CNRS #ENSRésumé
The Convention on Biological Diversity (CBD) aims at the conservation of all three levels of biodiversity, that is, ecosystems, species and genes. Genetic diversity represents evolutionary potential and is important for ecosystem functioning. Unfortunately, genetic diversity in natural populations is hardly considered in conservation strategies because it is difficult to measure and has been hypothesised to co-vary with species richness. This means that species richness is taken as a surrogate of genetic diversity in conservation planning, though their relationship has not been properly evaluated. We tested whether the genetic and species levels of biodiversity co-vary, using a large-scale and multi-species approach. We chose the high-mountain flora of the Alps and the Carpathians as study systems and demonstrate that species richness and genetic diversity are not correlated. Species richness thus cannot act as a surrogate for genetic diversity. Our results have important consequences for implementing the CBD when designing conservation strategies.
Auteurs, date et publication :
Auteurs Pierre Taberlet , Niklaus E. Zimmermann , Thorsten Englisch , Andreas Tribsch , Rolf Holderegger , Nadir Alvarez , Harald Niklfeld , Gheorghe Coldea , Zbigniew Mirek , Atte Moilanen , Wolfgang Ahlmer , Paolo Ajmone Marsan , Enzo Bona , Maurizio Bovio , Philippe Choler , Elżbieta Cieślak , Licia Colli , Vasile Cristea , Jean-Pierre Dalmas , Božo Frajman
Publication : Ecology Letters
Date : 2025
Volume : 15
Issue : 12
Pages : 1439-1448
Catégorie(s)
#CNRS #Lautaret #UGARésumé
ABSTRACT
Most genetic alterations that drive melanoma development and resistance to targeted therapy have been uncovered. In contrast, and despite their increasingly recognized contribution, little is known about the non-genetic mechanisms that drive these processes. Here, we performed in vivo gain-of-function CRISPR screens and identified SMAD3, BIRC3 and SLC9A5 as key actors of BRAFi-resistance and these genes promote the tumor growth capability of persister cells. We show that their expression levels increase during acquisition of BRAFi-resistance, and remain high in persister cells and during relapse. The upregulation of the SMAD3 transcriptional activity (SMAD3-signature) promotes a mesenchymal-like phenotype and BRAFi-resistance by acting as an upstream transcriptional regulator of potent BRAFi-resistance genes such as EGFR and AXL. This SMAD3-signature predicts resistance to both current melanoma therapies in different cohorts. Critically, chemical inhibition of SMAD3 may constitute amenable target for melanoma since it efficiently abrogates persister cells survival. Interestingly, decrease of SMAD3 activity can also be reached by inhibiting the aryl hydrocarbon receptor (AhR), another druggable transcription factor governing SMAD3 expression level. Our work expands our understanding of the biology of persister cells and highlight novel drug vulnerabilities that can be exploited to develop long-lasting antimelanoma therapies.
Auteurs, date et publication :
Auteurs Arthur Gautron , Laura Bachelot , Anaïs M. Quéméner , Sébastien Corre , Marc Aubry , Florian Rambow , Anaïs Paris , Nina Tardif , Héloïse M. Leclair , Cédric Coulouarn , Jean-Christophe Marine , Marie-Dominique Galibert , David Gilot
Publication : bioRxiv
Date : 2020
Pages : 2020.07.08.193102
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Matthew JW Cock , Rodolphe Rougerie
Publication : Zootaxa
Date : 2025
Volume : 4942
Issue : 3
Pages : 339-350
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Leaves of Mediterranean evergreens experience large variations in gas exchange rates over their life span due to aging and seasonally changing environmental conditions. Accounting for the changing respiratory physiology of leaves over time will help improve estimations of leaf and whole-plant carbon balances. Here we examined seasonal variations in light-saturated net CO2 assimilation (Amax), dark respiration (Rd) and the proportional change in Rd per 10 °C change in temperature (Q10 of Rd) in previous-year (PY) and current-year (CY) leaves of the broadleaved evergreen tree Quercus ilex L. Amax and Rd were lower in PY than in CY leaves. Differences in nitrogen between cohorts only partly explained such differences, and rates of Amax and Rd expressed per unit of leaf nitrogen were still significantly different between cohorts. The decline in Amax in PY leaves did not result in the depletion of total non-structural carbohydrates, whose concentration was in fact higher in PY than CY leaves. Leaf-level carbon balance modeled from gas exchange data was positive at all ages. Q10 of Rd did not differ significantly between leaf cohorts; however, failure to account for distinct Rd between cohorts misestimated canopy leaf respiration by 13% across dates when scaling up leaf measurements to the canopy. In conclusion, the decline in Amax in old leaves that are close to or exceed their mean life span does not limit the availability of carbohydrates, which are probably needed to sustain new growth, as well as Rd and nutrient resorption during senescence. Accounting for leaf age as a source of variation of Rd improves the estimation of foliar respiratory carbon release at the stand scale.
Auteurs, date et publication :
Auteurs Jesús Rodríguez-Calcerrada , Jean-Marc Limousin , Nicolas K Martin-StPaul , Carsten Jaeger , Serge Rambal
Publication : Tree Physiology
Date : 2025
Volume : 32
Pages : 14