Résumé
Milk production is highly dependent on the optimal development of the mammary epithelium. It is therefore essential to better understand mammary epithelial cell growth and maintenance from the related epithelial lineage during the animal life. Here, we characterized the epithelial lineage at puberty, lactation and dry-off in bovine using the cell surface markers CD49f, CD24, and CD10. The pubertal period was characterized by a high proportion of CD49fpos cells corresponding to various epithelial subpopulations, notably the CD24pos subpopulations. The proportion of CD49fpos cells was weaker during lactation and dry-off, and CD24pos cells were relatively few. Of note, the (sub)population profile at dry-off appeared close to that during lactation. Using a targeted gene approach, we associated specific genes with epithelial subpopulations, their expression level varying, or not, according to physiological stages. Caseins were only expressed in the CD49fmedCD24neg subpopulation. Basal marker genes (keratin(KRT)5, KRT14 and αSMA) were found in the CD49fhighCD24neg subpopulations. Luminal gene markers (KRT7, KRT8 and KRT19, CDH1 and the PRLR) were expressed in the CD49flowCD24neg subpopulation. The CD49flowCD24pos subpopulation, only abundant at puberty, expressed luminal gene markers and KI67 at high level. In contrast to others, the CD49fhighCD24pos cells accounted for a small proportion of total cells, decreasing from puberty to dry-off. They were characterized by expression of luminal and basal gene markers and low KI67 level. Interestingly, this subpopulation showed a remarkable stability of gene expression profile throughout physiological stages and bear the hallmark of quiescence that designate them as the potential bovine mammary stem cells.
Auteurs, date et publication :
Auteurs Laurence Finot , Eric Chanat , Frederic Dessauge
Publication : Journal of Mammary Gland Biology and Neoplasia
Date : 2019
Volume : 24
Issue : 2
Pages : 185-197
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Matthew G Letts , Vıctor Rolo , Serge Rambal
Publication : Trees
Date : 2025
Volume : 26
Pages : 479-491
Catégorie(s)
#CNRS #FORET PuechabonRésumé
With climate change, an aggravation in summer drought is expected in the Mediterranean region. To assess the impact of such a future scenario, we compared the response of Quercus pubescens, a drought-resistant deciduous oak species, to long-term amplified drought (AD) (partial rain exclusion in natura for 10 years) and natural drought (ND). We studied leaf physiological and physico-chemical trait responses to ND and AD over the seasonal cycle, with a focus on chemical traits including major groups of central (photosynthetic pigments and plastoquinones) and specialized (tocochromanols, phenolic compounds, and cuticular waxes) metabolites. Seasonality was the main driver of all leaf traits, including cuticular triterpenoids, which were highly concentrated in summer, suggesting their importance to cope with drought and thermal stress periods. Under AD, trees not only reduced CO2 assimilation (−42%) in summer and leaf concentrations of some phenolic compounds and photosynthetic pigments (carotenoids from the xanthophyll cycle) but also enhanced the levels of other photosynthetic pigments (chlorophylls, lutein, and neoxanthin) and plastochromanol-8, an antioxidant located in chloroplasts. Overall, the metabolomic adjustments across seasons and drought conditions reinforce the idea that Q. pubescens is highly resistant to drought although significant losses of antioxidant defenses and photoprotection were identified under AD.
Auteurs, date et publication :
Auteurs Justine Laoué , Michel Havaux , Brigitte Ksas , Béatrice Tuccio , Caroline Lecareux , Catherine Fernandez , Elena Ormeño
Publication : The Plant Journal
Date : 2025
Volume : 116
Issue : 5
Pages : 1293-1308
Catégorie(s)
#CNRS #FORET O3HPRésumé
Locating food in heterogeneous environments is a core survival challenge. The distribution of resources shapes foraging strategies, imposing demands on perception, learning and memory, and associated brain structures. Indeed, selection for foraging efficiency is linked to brain expansion in diverse taxa, from primates1 to Hymenopterans2. Among butterflies, Heliconius have a unique dietary adaptation, actively collecting and feeding on pollen, providing a source of essential amino acids as adults, negating reproductive senescence and facilitating an extended longevity3. Several lines of evidence suggest that Heliconius learn the spatial location of pollen resources within an individual’s home range4, and spatial learning may be more pronounced at these large spatial scales. However, experimental evidence of spatial learning in Heliconius, or any other butterfly, is so far absent. We therefore tested the ability of Heliconius to learn the spatial location of food rewards at three ecologically-relevant spatial scales, representing multiple flowers on a single plant, multiple plants within a locality, and multiple localities. Heliconius were able to learn spatial information at all three scales, consistent with this ability being an important component of their natural foraging behaviour.
Auteurs, date et publication :
Auteurs Priscila A. Moura , Fletcher J. Young , Monica Monllor , Marcio Z. Cardoso , Stephen H. Montgomery
Publication : Current Biology
Date : 2023
Volume : 33
Issue : 15
Pages : R797-R798
Catégorie(s)
#CNRS #Metatron terrestreAuteurs, date et publication :
Auteurs Roel JW Brienen , Oliver L Phillips , Ted R Feldpausch , Emanuel Gloor , Tim R Baker , Jon Lloyd , Gabriela Lopez-Gonzalez , Abel Monteagudo-Mendoza , Yadvinder Malhi , Simon L Lewis
Publication : Nature
Date : 2025
Volume : 519
Issue : 7543
Pages : 344
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs Cécile Richard-Hansen , Nicolas Surugue , Kamran Khazraie , Maïlys Le Noc , Pierre Grenand
Publication : Mammalia
Date : 2025
Volume : 78
Issue : 3
Pages : 291-301
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Many animals exhibit complex navigation over different scales and environments. Navigation studies in amphibians have largely focused on species with life histories that require accurate spatial movements, such as territorial poison frogs and migratory pond-breeding amphibians that show fidelity to mating sites. However, other amphibian species have remained relatively understudied, leaving open the possibility that well-developed navigational abilities are widespread. Here, we measured short-term space use in non-territorial, non-migratory cane toads (Rhinella marina) in their native range in French Guiana. After establishing site fidelity, we tested their ability to return home following translocations of 500 and 1000 m. Toads were able to travel in straight trajectories back to home areas, suggesting navigational abilities similar to those observed in amphibians with more complex spatial behavior. These observations break with the current paradigm of amphibian navigation and suggest that navigational abilities may be widely shared among amphibians.
Auteurs, date et publication :
Auteurs Daniel A. Shaykevich , Andrius Pašukonis , Lauren A. O'Connell
Publication : Journal of Experimental Biology
Date : 2022
Volume : 225
Issue : 2
Pages : jeb243048
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Abstract. Evolution of organic carbon content in soils has the potential to be a major driver of atmospheric greenhouse gas concentrations over the next century. Understanding soil carbon dynamics is a challenge due to a wide range of residence time of soil organic matter and limited constraints on the mechanisms influencing its persistence. In particular, large uncertainties exist on the persistence of pyrogenic organic carbon in soils. In order to characterise organic matter with varying degrees of persistence and distinguish pyrogenic organic carbon, we combined Rock-Eval analysis, a thermo-chemical method, with the benzene polycarboxylic acid molecular marker method and Raman spectroscopy, to characterise samples from long-term bare fallow experiments, progressively depleted in the most labile organic carbon over time. Considering the heterogeneity of soil samples, size fractions have been separated to distinguish pools of organic carbon with distinct properties. We observe that organic carbon dynamics is dependent on granulometry. A pool of organic carbon with intermediate residence time, from years to a few decades, representing ca 65 % of the bulk soil organic carbon stock, is mainly associated to fine fractions ( 20 µm) are rich in centennially-persistent organic carbon, representing ca 20 % of the initial organic carbon stock, due to the chemical recalcitrance of organic matter in these fractions, dominated by pyrogenic organic carbon. A second pool of persistent organic carbon, representing ca 15 % of the initial organic carbon stock, is associated with the clay fraction, indicating mechanisms of protection occurring at the submicron scale (
Auteurs, date et publication :
Auteurs Mathieu Chassé , Suzanne Luftalla , Lauric Cécillon , François Baudin , Samuel Abiven , Claire Chenu , Pierre Barré
Date : 2020
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Shengli Tao , Jean-Pierre Wigneron , Jerome Chave , Zhiyao Tang , Zhiheng Wang , Jiangling Zhu , Qinghua Guo , Yi Y. Liu , Philippe Ciais
Publication : NATURE CLIMATE CHANGE
Date : 2023
Volume : 13
Issue : 12
Pages : 1317+
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
Warmer climates accelerate the pace of life of lizards and this demographic change leads to a strong decrease in population growth rate that may ultimately result in population extinctions.
Auteurs, date et publication :
Auteurs Elvire Bestion , Aimeric Teyssier , Murielle Richard , Jean Clobert , Julien Cote
Publication : PLoS Biology
Date : 2015
Volume : 13
Issue : 10
Pages : e1002281