Résumé

Concern about the functional consequences of unprecedented loss in biodiversity has prompted biodiversity–ecosystem functioning (BEF) research to become one of the most active fields of ecological research in the past 25 years. Hundreds of experiments have manipulated biodiversity as an independent variable and found compelling support that the functioning of ecosystems increases with the diversity of their ecological communities. This research has also identified some of the mechanisms underlying BEF relationships, some context-dependencies of the strength of relationships, as well as implications for various ecosystem services that humankind depends upon. In this chapter, we argue that a multitrophic perspective of biotic interactions in random and non-random biodiversity change scenarios is key to advance future BEF research and to address some of its most important remaining challenges. We discuss that the study and the quantification of multitrophic interactions in space and time facilitates scaling up from small-scale biodiversity manipulations and ecosystem function assessments to management-relevant spatial scales across ecosystem boundaries. We specifically consider multitrophic conceptual frameworks to understand and predict the context-dependency of BEF relationships. Moreover, we highlight the importance of the eco-evolutionary underpinnings of multitrophic BEF relationships. We outline that FAIR data (meeting the standards of findability, accessibility, interoperability, and reusability) and reproducible processing will be key to advance this field of research by making it more integrative. Finally, we show how these BEF insights may be implemented for ecosystem management, society, and policy. Given that human well-being critically depends on the multiple services provided by diverse, multitrophic communities, integrating the approaches of evolutionary ecology, community ecology, and ecosystem ecology in future BEF research will be key to refine conservation targets and develop sustainable management strategies.

Auteurs, date et publication :

Auteurs Nico Eisenhauer , Holger Schielzeth , Andrew D. Barnes , Kathryn E. Barry , Aletta Bonn , Ulrich Brose , Helge Bruelheide , Nina Buchmann , François Buscot , Anne Ebeling , Olga Ferlian , Grégoire T. Freschet , Darren P. Giling , Stephan Hättenschwiler , Helmut Hillebrand , Jes Hines , Forest Isbell , Eva Koller-France , Birgitta König-Ries , Hans de Kroon

Date : 2019

Volume : 61

Pages : 1-54

Catégorie(s)

#CNRS #Ecotron de Montpellier

Auteurs, date et publication :

Auteurs Isabelle Maréchaux , Megan K Bartlett , Philippe Gaucher , Lawren Sack , Jérôme Chave

Publication : Journal of Plant Hydraulics

Date : 2025

Volume : 3

Pages : e004

Catégorie(s)

#CNRS #FORET Nouragues

Résumé

Purpose: CD90 (Thy-1) is a glycophosphatidylinositol-anchored glycoprotein considered as a surrogate marker for a variety of stem cells, including glioblastoma (GBM) stem cells (GSC). However, the molecular and cellular functions of CD90 remain unclear.Experimental Design: The function of CD90 in GBM was addressed using cellular models from immortalized and primary GBM lines, in vivo orthotopic mouse models, and GBM specimens' transcriptome associated with MRI features from GBM patients. CD90 expression was silenced in U251 and GBM primary cells and complemented in CD90-negative U87 cells.Results: We showed that CD90 is not only expressed on GSCs but also on more differentiated GBM cancer cells. In GBM patients, CD90 expression was associated with an adhesion/migration gene signature and with invasive tumor features. Modulation of CD90 expression in GBM cells dramatically affected their adhesion and migration properties. Moreover, orthotopic xenografts revealed that CD90 expression induced invasive phenotypes in vivo Indeed, CD90 expression led to enhanced SRC and FAK signaling in our GBM cellular models and GBM patients' specimens. Pharmacologic inhibition of these signaling nodes blunted adhesion and migration in CD90-positive cells. Remarkably, dasatinib blunted CD90-dependent GBM cell invasion in vivo and killed CD90high primary GSC lines.Conclusions: Our data demonstrate that CD90 is an actor of GBM invasiveness through SRC-dependent mechanisms and could be used as a predictive factor for dasatinib response in CD90high GBM patients. Clin Cancer Res; 23(23); 7360-74. ©2017 AACR.

Auteurs, date et publication :

Auteurs Tony Avril , Amandine Etcheverry , Raphaël Pineau , Joanna Obacz , Gwénaële Jegou , Florence Jouan , Pierre-Jean Le Reste , Masumeh Hatami , Rivka R. Colen , Brett L. Carlson , Paul A. Decker , Jann N. Sarkaria , Elodie Vauléon , Dan Cristian Chiforeanu , Anne Clavreul , Jean Mosser , Eric Chevet , Véronique Quillien

Publication : Clinical Cancer Research: An Official Journal of the American Association for Cancer Research

Date : 2017

Volume : 23

Issue : 23

Pages : 7360-7374

Catégorie(s)

#CNRS #EcoGenO #Université de Rennes

Résumé

In eukaryotes, the spatial and temporal organization of genome duplication gives rise to distinctive profiles of replication origin usage along the chromosomes. While it has become increasingly clear that these programs are important for cellular physiology, the mechanisms by which they are determined and modulated remain elusive. Replication initiation requires the function of cyclin-dependent kinases (CDKs), which associate with various cyclin partners to drive cell proliferation. Surprisingly, although we possess detailed knowledge of the CDK regulators and targets that are crucial for origin activation, little is known about whether CDKs play a critical role in establishing the genome-wide pattern of origin selection. We have addressed this question in the fission yeast, taking advantage of a simplified cell cycle network in which cell proliferation is driven by a single cyclin-CDK module. This system allows us to precisely control CDK activity in vivo using chemical genetics. First, in contrast to previous reports, our results clearly show that distinct cyclin-CDK pairs are not essential for regulating specific subsets of origins and for establishing a normal replication program. Importantly, we then demonstrate that the timing at which CDK activity reaches the S phase threshold is critical for the organization of replication in distinct efficiency domains, while the level of CDK activity at the onset of S phase is a dose-dependent modulator of overall origin efficiencies. Our study therefore implicates these different aspects of CDK regulation as versatile mechanisms for shaping the architecture of DNA replication across the genome.

Auteurs, date et publication :

Auteurs Anthony Perrot , Christopher Lee Millington , Blanca Gómez-Escoda , Diane Schausi-Tiffoche , Pei-Yun Jenny Wu

Publication : PLOS Genetics

Date : 2025

Volume : 14

Issue : 2

Pages : e1007214

Catégorie(s)

#CNRS #EcoGenO #Université de Rennes

Résumé

Primary consumers in freshwater ecosystems, such as the zooplankton organism Daphnia magna, are highly affected by cyanobacteria, both as they may use it as a food source but also by cyanobacterial metabolites present in the water. Here, we investigate the impacts of cyanobacterial metabolites focussing on the environmental realistic scenario of the naturally released mixture without crushing cyanobacterial cells or their uptake as food. Therefore, D. magna were exposed to two concentrations of cell free cyanobacterial spent medium from Microcystis aeruginosa PCC 7806 to represent higher and lower ecologically-relevant concentrations of cyanobacterial metabolites. Including microcystin-LR, 11 metabolites have been detected of which 5 were quantified. Hypothesising concentration and time dependent negative impact, survival, gene expression marking digestion and metabolism, oxidative stress response, cell cycle and molting as well as activities of detoxification and antioxidant enzymes were followed for 7 days. D. magna suffered from oxidative stress as both catalase and glutathione S-transferase enzyme activities significantly decreased, suggesting enzyme exhaustibility after 3 and 7 days. Moreover, gene-expressions of the 4 stress markers (glutathione S-transferase, glutathione peroxidase, catalase and thioredoxin) were merely downregulated after 7 days of exposure. Energy allocation (expression of Glyceraldehyde-3-phosphate dehydrogenase) was increased after 3 days but decreased as well after 7 days exposure. Cell cycle was impacted time dependently but differently by the two concentrations, along with an increasing downregulation of myosin heavy chain responsible for cell arrangement and muscular movements. Deregulation of nuclear hormone receptor genes indicate that D. magna hormonal steering including molting seemed impaired despite no detection of microviridin J in the extracts. As a consequence of all those responses and presumably of more than investigated molecular and physiological changes, D. magna survival was impaired over time, in a concentration dependent manner. Our results confirm that besides microcystin-LR, other secondary metabolites contribute to negative impact on D. magna survival and stress response.

Auteurs, date et publication :

Auteurs Gorenka Bojadzija Savic , Hervé Colinet , Myriam Bormans , Christine Edwards , Linda A. Lawton , Enora Briand , Claudia Wiegand

Publication : Toxicon

Date : 2021

Catégorie(s)

#CNRS #EcoGenO #Université de Rennes

Résumé

The inter- and seasonal patterns of water vapor and canopy carbon fluxes were compared for four forest ecosystems in two contrasting climatic zones in Europe. The eddy covariance and ancillary data were taken from the Carboeurope and FLUXNET databases and a linear modeling statistical analysis was made. The four sites were a high-density poplar (Populus spp.) short rotation coppice plantation (in Lochristi, Belgium) and a mature Scots pine (Pinus sylvestris) forest (in Brasschaat, Belgium) in the Temperate climate versus a fast-growing Eucalypt (Eucalyptus) plantation (in Espirra, Portugal) and a Holm oak (Quercus ilex) forest (in Puechabon, France) in the Mediterranean climate.

Auteurs, date et publication :

Auteurs Gabriel Pita

Publication : Agricultural and Forest Meteorology

Date : 2025

Pages : 14

Catégorie(s)

#CNRS #FORET Puechabon

Résumé

The increasing severity and frequency of natural disturbances requires a better understanding of their effects on all compartments of biodiversity. In Northern Fennoscandia, recent large-scale moth outbreaks have led to an abrupt change in plant communities from birch forests dominated by dwarf shrubs to grass-dominated systems. However, the indirect effects on the belowground compartment remained unclear. Here, we combined eDNA surveys of multiple trophic groups with network analyses to demonstrate that moth defoliation has far-reaching consequences on soil food webs. Following this disturbance, diversity and relative abundance of certain trophic groups declined (e.g., ectomycorrhizal fungi), while many others expanded (e.g., bacterivores and omnivores) making soil food webs more diverse and structurally different. Overall, the direct and indirect consequences of moth outbreaks increased belowground diversity at different trophic levels. Our results highlight that a holistic view of ecosystems improves our understanding of cascading effects of major disturbances on soil food webs.

Auteurs, date et publication :

Auteurs Irene Calderón-Sanou , Tamara Münkemüller , Lucie Zinger , Heidy Schimann , Nigel Gilles Yoccoz , Ludovic Gielly , Arnaud Foulquier , Mickael Hedde , Marc Ohlmann , Mélanie Roy , Sara Si-Moussi , Wilfried Thuiller

Publication : Scientific Reports

Date : 2025

Volume : 11

Issue : 1

Pages : 15054

Catégorie(s)

#CNRS #eDNA

Résumé

Key message  The development of a new, low-impact, canopy-access system is described from its original idea until the final realization after about 30 years.

Auteurs, date et publication :

Auteurs Gerhard Gottsberger

Publication : Trees

Date : 2025

Volume : 31

Issue : 3

Pages : 791-812

Catégorie(s)

#CNRS #FORET Nouragues

Auteurs, date et publication :

Auteurs Terry W Henkel , Andrew W Wilson , M Catherine Aime , Janina Dierks , Jessie K Uehling , Melanie Roy , Heidy Schimann , Felipe Wartchow , Gregory M Mueller

Publication : Mycologia

Date : 2025

Volume : 106

Issue : 2

Pages : 307-324

Catégorie(s)

#CNRS #FORET Nouragues

Auteurs, date et publication :

Auteurs Bart Buyck , Pierre-Arthur Moreau , Régis Courtecuisse , Alejandro Kong , Mélanie Roy , Valérie Hofstetter

Publication : Cryptogamie, Mycologie

Date : 2025

Volume : 37

Issue : 3

Pages : 391-404

Catégorie(s)

#CNRS #FORET Nouragues