Résumé
Upon advances in sequencing techniques, more and more morphologically identical organisms are identified as cryptic species. Often, mutualistic interactions are proposed as drivers of diversification. Species of the neotropical parabiotic ant association between Crematogaster levior and Camponotus femoratus are known for highly diverse cuticular hydrocarbon (CHC) profiles, which in insects serve as desiccation barrier but also as communication cues. In the present study, we investigated the association of the ants’ CHC profiles with genotypes and morphological traits, and discovered cryptic species pairs in both genera. To assess putative niche differentiation between the cryptic species, we conducted an environmental association study that included various climate variables, canopy cover, and mutualistic plant species. Although mostly sympatric, the two Camponotus species seem to prefer different climate niches. However in the two Crematogaster species, we could not detect any differences in niche preference. The strong differentiation in the CHC profiles may thus suggest a possible role during speciation itself either by inducing assortative mating or by reinforcing sexual selection after the speciation event. We did not detect any further niche differences in the environmental parameters tested. Thus, it remains open how the cryptic species avoid competitive exclusion, with scope for further investigations.
Auteurs, date et publication :
Auteurs Juliane Hartke , Philipp P. Sprenger , Jacqueline Sahm , Helena Winterberg , Jérôme Orivel , Hannes Baur , Till Beuerle , Thomas Schmitt , Barbara Feldmeyer , Florian Menzel
Publication : Ecology and Evolution
Date : 2025
Volume : 9
Issue : 16
Pages : 9160-9176
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouAuteurs, date et publication :
Auteurs Flavia A Esteves , Brian L Fisher
Publication : ZooKeys
Date : 2025
Volume : 1074
Pages : 83
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs Brigitte Vinçon-Leite , Yi Hong , Viet Tran Khac , Denis Plec , Chenlu Li , Philippe Dubois , Mohamed Saad , Bruno J Lemaire , Gabriel Hmimina , Kamel Soudani , others
Date : 2025
Catégorie(s)
#⛔ No DOI found #CNRS #ENS #PLANAQUARésumé
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. 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 highlights novel drug vulnerabilities that can be exploited to develop long-lasting antimelanoma therapies.
Auteurs, date et publication :
Auteurs Arthur Gautron
Publication : EMBO Molecular Medicine
Date : 2021
Volume : 13
Issue : 5
Pages : e13466
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Benoit De Thoisy , Ana Carolina Pavan , Marguerite Delaval , Anne Lavergne , Thomas Luglia , Kevin Pineau , Manuel Ruedi , Vincent Rufray , François Catzeflis
Publication : Acta Chiropterologica
Date : 2025
Volume : 16
Issue : 1
Pages : 1-13
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs V. E. Mayer , J. Lauth , J. Orivel
Publication : Insectes Sociaux
Date : 2025
Volume : 64
Issue : 3
Pages : 365-371
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Abstract Measuring leaf gas exchange from canopy leaves is fundamental for our understanding of photosynthesis and for a realistic representation of carbon uptake in vegetation models. Since canopy leaves are often difficult to reach, especially in tropical forests with emergent trees up to 60 m at remote places, canopy access techniques such as canopy cranes or towers have facilitated photosynthetic measurements. These structures are expensive and therefore not very common. As an alternative, branches are often cut to enable leaf gas exchange measurements. The effect of branch excision on leaf gas exchange rates should be minimized and quantified to evaluate possible bias. We compared light-saturated leaf net photosynthetic rates measured on excised and intact branches. We selected branches positioned at three canopy positions, estimated relative to the top of the canopy: upper sunlit foliage, middle canopy foliage, and lower canopy foliage. We studied the variation of the effects of branch excision and transport among branches at these different heights in the canopy. After excision and transport, light-saturated leaf net photosynthetic rates were close to zero for most leaves due to stomatal closure. However, when the branch had acclimated to its new environmental conditions?which took on average 20 min?light-saturated leaf net photosynthetic rates did not significantly differ between the excised and intact branches. We therefore conclude that branch excision does not affect the measurement of light-saturated leaf net photosynthesis, provided that the branch is recut under water and is allowed sufficient time to acclimate to its new environmental conditions.
Auteurs, date et publication :
Auteurs Lore T. Verryckt , Leandro Van Langenhove , Philippe Ciais , Elodie A. Courtois , Sara Vicca , Josep Peñuelas , Clément Stahl , Sabrina Coste , David S. Ellsworth , Juan M. Posada , Michael Obersteiner , Jérôme Chave , Ivan A. Janssens
Publication : Biotropica
Date : 2025
Volume : 52
Issue : 4
Pages : 608-615
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
In the initial, online publication, the authors' given names were captured as family names and vice versa. The names are correctly shown here. The original article has been corrected.
Auteurs, date et publication :
Auteurs Paloma Compes , Emeline Tabouret , Amandine Etcheverry , Carole Colin , Romain Appay , Nicolas Cordier , Jean Mosser , Olivier Chinot , Hervé Delingette , Nadine Girard , Henry Dufour , Philippe Metellus , Dominique Figarella-Branger
Publication : Journal of Neuro-Oncology
Date : 2019
Volume : 142
Issue : 3
Pages : 521-521
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Thomas Bourguignon , Thomas Drouet , Jan Šobotník , Robert Hanus , Yves Roisin
Publication : PloS one
Date : 2025
Volume : 10
Issue : 11
Pages : e0143776
Catégorie(s)
#CNRS #FORET NouraguesRésumé
BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is highly metastatic. Cabozantinib, an anti-angiogenic tyrosine kinase inhibitor that targets c-MET, provided interesting results in metastatic ccRCC treatment.
OBJECTIVE: To understand better the role of c-MET in ccRCC, we assessed its status in a population of patients with metastatic ccRCC.
PATIENTS AND METHODS: For this purpose, tumor samples were analyzed for c-MET expression by immunohistochemistry (IHC), for c-MET copy number alterations by fluorescence in situ hybridization (FISH), and for c-MET mutations by next generation sequencing (NGS) in a retrospective cohort of 90 primary ccRCC of patients with metastases treated by first-line sunitinib. The expression of c-MET was correlated with pathological, immunohistochemical (VEGFA, CAIX, PD-L1), clinical, and molecular criteria (VHL status) by univariate and multivariate analyses and to clinical outcome using Kaplan-Meier curves compared by log-rank test.
RESULTS: Of ccRCC, 31.1% had low c-MET expression (absent to weak intensity by IHC) versus 68.9% with high expression (moderate to strong intensity). High expression of c-MET was associated with a gain in FISH analysis (p=0.0284) without amplification. No mutations were detected in NGS. Moreover, high c-MET expression was associated with lymph node metastases (p=0.004), sarcomatoid component (p=0.029), VEGFA (p=0.037), and PD-L1 (p=0.001) overexpression, the only factor that remained independently associated (p<0.001) after logistic regression. No difference was observed in clinical outcomes.
CONCLUSION: This study is the first to analyse c-MET status in metastatic ccRCC. The high expression of c-MET in the majority of ccRCC and its independent association with PD-L1 expression, may suggest a potential benefit from combining c-MET inhibitors and targeted immunotherapy.
Auteurs, date et publication :
Auteurs Solène-Florence Kammerer-Jacquet , Sarah Medane , Karim Bensalah , Jean-Christophe Bernhard , Mokrane Yacoub , Frantz Dupuis , Alain Ravaud , Grégory Verhoest , Romain Mathieu , Benoit Peyronnet , Angélique Brunot , Brigitte Laguerre , Alexandra Lespagnol , Jean Mosser , Frédéric Dugay , Marc-Antoine Belaud-Rotureau , Nathalie Rioux-Leclercq
Publication : Targeted Oncology
Date : 2017
Volume : 12
Issue : 4
Pages : 487-494