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Scooped by
Saclay Plant Sciences
November 27, 3:51 PM
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A review on molecular mechanisms of beneficial plant-microbe interactions IPS2 SPS In the frame of the COST Action “ROOT-BENEFIT” (CA22142) from the European Cooperation in Science and Technology, Florian Frugier from IPS2 coordinated the writing of a European collaborative review, published in Plant Communications, summarizing our current knowledge on the molecular mechanisms controlling different beneficial plant root-microbe interactions, namely arbuscular mycorrhiza, the rhizobium-legume symbiosis, ectomycorrhiza, as well as fungal and bacterial endophytic associations. The authors notably highlight what are the main shared mechanisms, as well as the knowledge gaps, with a special focus on the signaling pathways required for microbes to be recognized as beneficial, the metabolic pathways that provide nutritional benefits to the plant, and the regulatory pathways modulating the extent of the symbiosis establishment depending on soil nutrient availability and plant needs. By summarizing this knowledge, this review aims to promote the move from an intensive chemically-synthesized fertilizers- and pesticides-based agriculture towards the use of plant-microbe beneficial interactions in the frame of a more sustainable agriculture.
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Scooped by
Saclay Plant Sciences
November 26, 7:51 AM
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Transcriptome analysis is widely used in research projects. By providing a comprehensive view of an organism’s gene activity, transcriptomics enables the exploration and identification of mechanisms underlying the observed phenotypes. This approach can be applied to any sample (tissue or species); however, its use is often limited to relatively simple experimental designs. There are likely two reasons for this. First, the vast amount of data generated requires complex and expert analysis. Some believe that artificial intelligence and neural networks can overcome this barrier, but these approaches require a high number of measures to identify explanatory and predictive structures among the tens of thousands of transcripts analyzed in each sample. Second, agroecological challenges require field analyses under much more complex and heterogeneous conditions (multiple species, multiple factors) than those found in laboratory settings. This again necessitates the analysis of a very large number of samples. To bring the power and sensitivity of transcriptomics to these major challenges, it must be made widely accessible and its costs drastically reduced. The POPS transcriptomic platform offers a high-throughput plant transcriptome screening service (several hundred samples per project) at a very low cost, thanks to BRB-Seq technology ((Bulk RNA barcoding and sequencing) that allows the reduction of reaction volumes and the automation of all steps (RNA extraction, library preparation, quantification, and multiplexing). Contacts:
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Scooped by
Saclay Plant Sciences
November 24, 9:55 AM
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The HeatDDR Doctoral Network was officially launched on March 1, 2025, merging 17 European partners to train 9 PhD students in Plant Sciences. Funded by Horizon Europe through the Marie Skłodowska-Curie Actions (€2.2 million), this four-year project is coordinated by the Paris-Saclay University, with Dr. Cécile Raynaud (Research Director at the Institute of Plant Sciences Paris-Saclay, IPS2) as scientific coordinator. The initiative addresses one of the biggest challenges in modern agriculture: sustaining crop productivity and food security to face climate change. Northern Europe is expected to see longer, warmer, and more humid summers, while southern Europe faces increasing heat and drought stress. HeatDDR focuses on understanding how heat stress affects plant development, particularly through the DNA Damage Response (DDR), a mechanism that plays a dual role, contributing to thermotolerance while limiting plant growth. By studying DDR, the project aims to maintain crop yields without compromising stress resilience. The network provides an interdisciplinary training program, combining academic research together with practical training in both universities and industry. Each PhD student will benefit from supervision by multiple partners, advanced technical training, and the development of soft skills essential for a scientific career. The HeatDDR project kick-off meeting will take place on December 2–3, 2025, in Giessen, Germany, bringing together the newly recruited PhDs and other members of the consortium to officially launch the collaborative research and training initiatives. Over the next four years, the network will hold additional workshops and a final three-day symposium hosted by the Paris-Saclay University in 2029, where students will present their research alongside invited experts.
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Scooped by
Saclay Plant Sciences
October 13, 9:30 AM
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COMMUNIQUE DE PRESSE - Sophie Nicklaus est officiellement nommée directrice scientifique Alimentation et Santé pour 4 ans, par Philippe Mauguin, président-directeur général d’INRAE, après consultation de son conseil d’administration ce 13 octobre. Désormais membre du collège de direction de l’institut, Sophie Nicklaus était depuis avril 2024 directrice scientifique adjointe Alimentation et Bioéconomie auprès de Monique Axelos qui fera valoir ses droits à la retraite à la fin de l’année. Face aux enjeux de sécurité et souveraineté alimentaire, de durabilité et de coût de l’alimentation et aux défis de santé publique et d’innovation, INRAE a choisi de cibler les missions de la nouvelle directrice scientifique sur les domaines de l’alimentation et de la santé, afin de contribuer à l’alimentation de demain, une alimentation saine, durable et accessible à tous. Une direction scientifique dédiée à la bioéconomie, préfigurée par Monique Axelos, sera mise en place à la fin de l’année.
"Flavonoid metabolites dye many plant organs such as flowers, fruits, seeds, leaves or tubers. Over the past 150 years, tracking flavonoid-related colour changes in plants has shaped the foundation of many modern biology questions. This includes ground-breaking discoveries such as Gregor Mendel’s law of inheritance (using white and purple pea flowers), Barbara McClintock’s identification of transposable elements (through her research on variably coloured maize kernels) or Carolyn Napoli’s description of co-suppression (based on her observations of altered and novel flower colouration in petunia). In recent decades, the intricate, diverse and finely tuned flavonoid pathway has been unravelled and the understanding of this pathway across various plant species owes much to the characterization of mutants disrupted in the biosynthesis, transport and storage of flavonoids that similarly displayed modified flower and seed pigmentation (Winkel-Shirley 2001; Koes et al. 2005; Lepiniec et al. 2006). The model plant A. thaliana provided a wealth of such mutants (transparent testa mutants, tt) exhibiting altered seedcoat colours (Fig. 1) (Koornneef 1990; Shirley et al. 1992; Lepiniec et al. 2006). Their characterization enabled researchers to associate genes or loci with flavonoid-related functions. However, although their visual and non-lethal phenotypes were easy to identify and offered insight into the disrupted gene functions, further investigation was required to confirm these functions. Beyond colour, to fully unravel this pathway, it has become essential to individually characterize the seed flavonoids, determine their spatial and temporal distribution, and their diversity. This laid the groundwork for validating locus functions, characterizing novel gene roles, and identifying as well as quantifying flavonoid accumulation in other plants".
Via Loïc Lepiniec
One of MASC’s major goals is to strengthen international cooperation. Through the combined efforts promoted by MASC, more progress in Arabidopsis research is achieved and redundancy is reduced. Since 1990, Arabidopsis researchers and representatives from community projects and resources regularly report their progress and reccommend future directions in Arabidopsis research. Since 2002 the annual Multinational Arabidopsis Steering Committee (MASC) report is compiled by MASC chairs and coordinator and published at the International Conference on Arabidopsis Research (ICAR).
Via Loïc Lepiniec
La flexibilité génétique du réseau NGAL/CUC/KLUH contribue à la pléiotropie des gènes au cours du développement végétal
Dans une étude publiée dans The Plant Journal, l’équipe « Facteurs de Transcription et Architecture » de l’Institut Jean-Pierre Bourgin - Sciences du Végétal - IJPB (INRAE/AgroParisTech/UPSaclay, Versailles) s’est intéressée aux réseaux génétiques contrôlant le développement des plantes et à leur reconfiguration. La manière dont ces réseaux peuvent être modulés entre différents organes au sein d’un même organisme, en particulier pour les gènes pléiotropes exerçant plusieurs fonctions, reste encore mal comprise. Pour explorer cette question, l’équipe a étudié, par des approches génétiques et d’analyse d’expression des gènes, les interactions entre les facteurs de transcriptions NGATHA-LIKE (NGAL), CUP-SHAPED COTYLEDON (CUC) et le cytochrome P450 KLUH dans différents organes de la plante modèle Arabidopsis thaliana. Ils montrent ainsi que le module de régulation NGAL/CUC/KLUH est remanié de manière organe-spécifique. Par exemple, la régulation de la croissance dans les pétales dépend majoritairement de l’action des NGAL sur KLUH, tandis que dans les feuilles caulinaires, les gènes CUC et KLUH fonctionnent parallèlement en aval des NGAL. De façon intéressante, ces différences de dialogue génétique s’expliquent en partie par les patrons d’expression spatiale distincts des gènes CUC, KLUH et NGAL dans chaque organe, reflétant des contraintes ou des dynamiques développementales spécifiques. Ce travail met ainsi en lumière une modulation et une reconfiguration des différents réseaux génétiques associés au module NGAL/CUC/KLUH. Cette flexibilité des réseaux de régulation facilite la pléiotropie génétique et contribue à l’innovation évolutive et à la robustesse développementale chez la plante. -> Contact : patrick.laufs@inrae.fr
Via Life Sciences UPSaclay
Seed development in Arabidopsis thaliana is largely controlled by a set of transcription factors (TFs) called LAFL, including LEAFY COTYLEDON 2 (LEC2). In this study, we investigated the structure/function relationships of the protein LEC2 outside the well-described B3 DNA-binding domain. The results presented here unveil the presence of transcription activation domains (ADs) within the unstructured ends of the protein that are conserved in eudicots. Expression in both yeast and moss protoplasts of deleted and mutated versions of LEC2 confirmed the transcriptional activity of these ADs. Surprisingly, the expression of LEC2 variants lacking their ADs restored a wild-type seed phenotype in lec2 mutant, showing that these ADs are not essential for LEC2 function in seed development. Moreover, ZmAFL2/ZmABI19, a maize B3 factor related to LEC2 but deprived of N-ter AD, can also complement lec2 seed phenotype and induce abnormal vegetative development when overexpressed in Arabidopsis, supporting this observation. This work suggests that LEC2 can act both as a classical transcriptional activator or without transactivation activity, probably through its interaction with the pioneer factor LEC1. Taken together, the results provide important insights into the function of the LAFL master regulators during seed development, from cell differentiation to storage accumulation in seed.
Via Loïc Lepiniec
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Scooped by
Saclay Plant Sciences
July 17, 4:17 AM
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Les plantes dans un environnement à fort CO2 : contraintes et opportunités Ce colloque vise à dresser un état des connaissances et des enjeux de l'influence exercée par l’élévation du CO2 atmosphérique sur le monde végétal. Inscriptions à venir ! Colloque académique destiné à un public scientifique ou non scientifique éclairé. Le dérèglement climatique engendré par l’élévation du CO2 atmosphérique et autres gaz à effet de serre aggrave les contraintes abiotiques exercées sur les plantes : sécheresse, chaleur, événements climatiques extrêmes, mettant en danger leur productivité et même leur survie. Par ailleurs, et de manière singulière par rapport aux autres organismes vivants, une concentration plus élevée de CO2 stimule la croissance de la plupart des végétaux, du fait d’une photosynthèse accrue. Cet effet positif, dénommé « fertilisation CO2 », a également un impact important sur le transfert de carbone dans les sols, les plantes contribuant ainsi à l’atténuation du changement climatique. Organisé conjointement par l'Académie des sciences et l'Académie d'agriculture de France, ce colloque abordera l’état des connaissances multidisciplinaires dans ces domaines et fera la synthèse des contraintes et opportunités que représente pour les plantes et les agroécosystèmes associés une élévation du CO2 atmosphérique. Organisateurs Christophe Maurel, membre de l'Académie des sciences, directeur de recherche au CNRS, directeur de l'Institut des sciences des plantes de Montpellier (IPSiM - CNRS/Inrae/Université de Montpellier) Alain Gojon, membre correspondant de l’Académie d’agriculture de France, directeur de recherche honoraire d’Inrae, ancien directeur (2012-2020) du laboratoire de Biochimie et physiologie moléculaire des plantes (B&PMP - CNRS/Inrae/Université de Montpellier/Institut Agro), devenu l’Institut des sciences des plantes de Montpellier (IPSiM). Philippe Gate, membre de l’Académie d’agriculture de France, ex-directeur scientifique d’Arvalis-Institut du végétal (2009-2021) Intervenants (programme détaillé à venir) Marie-Odile Bancal, maître de conférences à AgroParisTech, laboratoire Écologie fonctionnelle et écotoxicologie des agroécosystèmes (Ecosys – Université Paris-Saclay/Inrae/AgroParisTech) Claire Chenu, membre correspondant de l’Académie d’agriculture de France, membre de l’Académie des technologies, directrice de recherche à Inrae, professeure consultante à AgroParisTech, laboratoire Écologie fonctionnelle et écotoxicologie des agroécosystèmes (Ecosys – Université Paris-Saclay/Inrae/AgroParisTech) Philippe Ciais, membre de l’Académie des sciences, membre de l'Académie d'agriculture de France, directeur de recherche au CEA, Laboratoire des sciences du climat et de l’environnement (LSCE - CEA/CNRS/Université Versailles Saint-Quentin-en-Yvelines) de l’Institut Pierre-Simon Laplace. Pierre Crozet, maître de conférences à Sorbonne Université, laboratoire de Biologie computationnelle, quantitative et synthétique (CQSB – CNRS/Sorbonne Université) Meije Gawinowski, chargée de recherche à Inrae, laboratoire Écologie fonctionnelle et écotoxicologie des agroécosystèmes (Ecosys – Université Paris-Saclay/Inrae/AgroParisTech) Xenie Johnson, directrice de recherche au CEA, responsable adjointe de l’équipe Photosynthèse et Environnement Nathalie Leonhardt, directrice de recherche au CEA, responsable de l’équipe Plant Environmental Physiology and Stress Signaling (PEPSS), Institut Biosciences et Biotechnologies d'Aix - Marseille (BIAM – Aix-Marseille Université/CEA/CNRS) David Makowski, directeur de recherche, Inrae/AgroParisTech/Université Paris-Saclay, Département AgroEcosystem Antoine Martin, directeur de recherche au CNRS, responsable de l’équipe Signalisation nitrate et régulation par l’environnement (Sirene), Institut des sciences des plantes de Montpellier (IPSiM – CNRS/Inrae/Université de Montpellier)
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Scooped by
Saclay Plant Sciences
June 1, 1:26 PM
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Scooped by
Saclay Plant Sciences
May 21, 7:45 AM
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The composition of cellular proteomes rapidly adjusts in response to internal and external stimuli. Protein modifications add yet another layer of plasticity to this intricately balanced and dynamic system. In humans, N-terminal acetylation (NTA) is a pervasive and essential protein modification catalyzed by seven Nα-acetyltransferases (Nat) in a co-translational or post-translational manner. In this talk, I will summarize our efforts to characterize the plant Nat machinery and its relevance for coordinating growth and development upon diverse environmental challenges. Our findings uncovered that NTA is a phytohormone-controlled mechanism determining global proteome stability, which is particularly critical for the drought stress response of plants.
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Scooped by
Saclay Plant Sciences
November 26, 2:53 PM
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This Summer school is organized by the Saclay Plant Sciences (SPS) network, one of the largest European plant sciences communities. scRNAseq approaches have revolutionized the way biologists approach their research subjects, by making it possible to dissect molecular mechanisms at the single-cell level. But although technological developments have recently made these approaches more accessible, their expensive use still requires significant technical training, including the good conception of experimental designs, the preparation of samples as well as their bioinformatics analyses. In addition, different protocols and various bioinformatics and statistical analyzes are available, and it can be difficult to choose the most relevant ones for the biological question at hand. Over five days, the SPS Summer School 2026 will cover all the stages of a scRNAseq project in plants. Through a combination of lectures and practical work, the many specific features of plant models will be highlighted by experts from the Saclay Plant Sciences network (CNRS and INRAE), the ViB in Ghent and the Pasteur Institute. After this international school, participants will:
– Have an overview of the different scRNAseq technologies and understand their pros and cons.
– Be able to design experiments depending on the biological question.
– Be trained on sample preparation techniques for single cell and single nuclei
– Understand the different steps of bioinformatics and statistical analysis
– Have a better biological interpretation of results
– Have facilitated exchanges with technology platforms, bioinformaticians, and biostatisticians in order to successfully complete their scRNAseq project The summer school will bring together outstanding and enthusiastic young scientists (PhD students and post-docs) from all over the world in order to exchange knowledge and ideas. It is limited to a small group of participants (20 maximum) to privilege informal interactions and scientific discussions Application deadline: March 12, 2026 (midnight)
Answers will be sent mid-April at the latest.
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Scooped by
Saclay Plant Sciences
November 24, 10:02 AM
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Bruno Guillotin has joined the IPS2 unit (Institute of Plant Sciences Paris-Saclay) as a CNRS Research Scientist. He was recruited in February 2025. After studying Plant Biology and Physiology, he completed his PhD between 2013 and 2016 at the Plant Science Research Laboratory (LRSV – Toulouse) under the supervision of Guillaume Bécard and Jean-Philippe Combier. His doctoral work focused on the autoregulation of arbuscular mycorrhizal symbiosis in Medicago truncatula. Following his PhD, he turned his attention to the study of root development in various plant species as a postdoctoral researcher in Kenneth Birnbaum’s group at New York University. There, supported by a Human Frontiers Long-Term Fellowship, he developed numerous protocols for single-cell transcriptomics (single-cell RNA-seq), which he implemented to study gene evolution across agronomically relevant species (maize, sorghum, millet), as well as to investigate cell regeneration in the roots of Arabidopsis thaliana. In 2025, he was appointed as a CNRS Research Scientist and was also awarded the CNRS–INSERM ATIP-Avenir grant. At IPS2, Bruno Guillotin’s research focuses on understanding how plant cells communicate through plasmodesmata, aiming to identify which proteins and peptides move from one cell to another and contribute to organ morphogenesis in plants. His work combines single-cell RNA-seq, proteomics, genomics, and bioinformatics approaches.
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Scooped by
Saclay Plant Sciences
November 14, 7:20 AM
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Surprisingly, differences in phenotypes and gene expression are observed between genetically identical individuals grown in the same environment. While we now have a good knowledge of the source and consequences of transcriptional differences observed between cells, in particular for unicellular organisms, it is still very scarce when it comes to variability between multicellular organisms. Using plants as a model we analysed the establishment, maintenance and consequences of inter-individual transcriptional variability. We showed, for a gene of interest, that differences in expression between plants are established in young seedlings and maintained over several days. Our results also indicate that these differences in expression can explain phenotypic variability between plants such as for the root growth. Finally, using a genome-wide approach, we found a co-expression in seedlings for our gene of interest, involved in nitrate nutrition, and genes involved in photosynthesis. All in all, our study suggests that a global coordination of the genes involved in the carbon/nitrate balance in plants is established in young seedlings, with differences between plants, and then maintained over time.
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Scooped by
Saclay Plant Sciences
October 9, 2:28 AM
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International Master in Plant Sciences track of the Biology AgroSciences master degree https://www.master-sciences-du-vegetal.fr/eng We are delighted to share that the International Master in Plant Sciences track of the Biology AgroSciences Master degree will soon be launching (September 2026). Fully taught in English (First and second year) and embedded in the Saclay Plant Sciences Excellence Network, this program will train a new generation of talented students to tackle the most pressing challenges in plant research — from climate resilience to sustainable agriculture.
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Scooped by
Saclay Plant Sciences
September 30, 4:37 AM
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Chemical interactions between plants and their environment: from the molecule to the field
23-25 September 2026 - IJPB, INRAE Ile-de-France - Versailles-Saclay
The IJPB is organising the 3rd edition of its international symposium. Following the editions in 2018 and 2024, this event will take place in Versailles from 23 to 25 September 2026. Save the date!
The IJPB Symposium 2026 is dedicated to "Chemical interactions between plants and their environment: from the molecule to the field", a booming research field in which IJPB develops integrative approaches bridging plant metabolism and its effect on biotic/abiotic interactions and vice versa.
The symposium will comprise an opening lecture and four thematic sessions, each involving an international and an IJPB keynote speaker, as well as presentations from participants selected from submitted abstracts. The themes of each session are as follows:
1 - Identification/analysis of chemical signals involved in plant response to their environment
2 - Molecular and cellular mechanisms of chemical responses to biotic and abiotic stress: Perception and transduction of chemical signals
3 - Integration of chemical interactions in ecological communities and agroecosystems
4 - Agroecological innovations derived from the study of how plants interact with their environment
This exciting meeting aims to foster collaborations and facilitate knowledge exchange among participants by bringing together renowned specialists in the field and a high level of interdisciplinary.
The symposium will also feature a workshop on plant specialized metabolite analysis, conducted in collaboration with the Chemistry/Metabolism platform PO-Chem, and a tour of the Plant Facilities PO-Plants and the Phenoscope PO-Pheno, all three of which are part of the Plant Observatory (PO) of the IJPB.
Ahead of the symposium, the ENVIE Network will hold its 5th plenary edition in Versailles from 21 to 23 September 2026, organised as part of a MULTISTRESS satellite workshop.
We look forward to meeting you in Versailles! Further information will be available by November 2025.
In connection with the research developed at the Institute Jean-Pierre Bourgin for Plant Sciences.
Dans une étude publiée dans Journal of Experimental Botany, des chercheurs de l’Institut Jean-Pierre Bourgin - Sciences du Végétal - IJPB (INRAE/AgroParisTech/UPSaclay, Versailles), de l’Institute for Agriculture and Forestry Systems in the Mediterranean (Catania, Italie) et des Royal Botanic Gardens - Kew, (Ardingly, Angleterre) ont étudié la biosynthèse de l’huile dans la graine de Cakile maritima, une espèce halophyte sauvage de la famille des Brassicacées. En analysant indépendamment les deux tissus zygotiques de la graine, l'embryon et l'albumen, il a été démontré que l'embryon est le principal site d'accumulation de l’huile. Il est à noter que la composition en acides gras de l’huile diffère considérablement entre les tissus zygotiques. La moitié des acides gras de l'albumen sont des monoinsaturés de type oméga-7, qui sont largement absents de l'embryon. En revanche, l'embryon présente une induction plus forte des voies de biosynthèse des acides gras de type oméga-9 et polyinsaturés, ce qui reflète une régulation spécifique des gènes du métabolisme des acides gras dans chaque tissu. En outre, les graines collectées dans différentes niches écologiques le long d'un gradient latitudinal révèlent que la température environnementale affecte la composition en acides gras de l’huile, en particulier la proportion d'acides gras polyinsaturés dans l'embryon. Ces résultats soulignent la diversité métabolique et le potentiel d'adaptation de C. maritima, dont la teneur en huile élevée des graines, associée à la capacité de la plante à prospérer dans des environnements salins avec un minimum d'apports, sont autant de caractéristiques particulièrement intéressantes dans une optique de diversification des cultures oléagineuses. -> Contact : sebastien.baud@inrae.fr
Via Life Sciences UPSaclay
Dans une étude parue dans mSystems, des scientifiques de l’Institut Jean-Pierre Bourgin - Sciences du Végétal - IJPB (INRAE/AgroParisTech/UPSaclay, Versailles) ont étudié un monde encore méconnu : la « spermosphère ». Cette interface entre la graine en germination et l’environnement comporte une large diversité chimique et microbienne, directement façonnée par les molécules issues des métabolismes central et spécialisé que la graine libère dès l’imbibition. En travaillant sur un panel de diversité génétique du haricot commun (Phaseolus vulgaris L.), les chercheurs ont analysé à la fois les métabolites libérés par les graines et les communautés de micro-organismes de la spermosphère. Ils ont découvert des métabolites exsudés par la graine, dont des acides aminés et dipeptides, des flavonoïdes et des terpènes, chacun pouvant influencer les micro-organismes qui s’installent autour de la graine. Ainsi, ils ont pu caractériser des dizaines de familles de bactéries et de champignons. Comme une véritable architecte, la graine crée donc son propre environnement, en fonction de son identité génétique et de son environnement de production. Ces échanges métaboliques entre la graine en germination et sa cohorte microbienne sont essentiels car ils contribuent à la santé et à la qualité physiologique de la future plante. Cette découverte change notre regard. Les résultats révèlent que la graine ne subit pas passivement son environnement, mais contribue activement à façonner la communauté microbienne qui l’entoure. Ces travaux ouvrent la voie à de nouvelles stratégies de sélection variétale et au développement de traitements bio-inspirés pour améliorer la vigueur des semences. Ils participent également à l’émergence de pratiques agricoles plus durables, en misant sur la compréhension fine des alliances invisibles entre graines, molécules et microbes. -> Contact : massimiliano.corso@inrae.fr / loic.rajjou@agroparistech.fr / chandrodhay.saccaram@inrae.fr
Via Life Sciences UPSaclay
La reproduction sexuée est une source majeure de diversité génétique, au cours de laquelle les chromosomes homologues (parentaux) sont alternativement associés (fécondation), puis séparés (méiose). Pour que la séparation des chromosomes en méiose soit équilibrée, les chromosomes doivent se reconnaître et s’associer en paires (bivalents). Toute perturbation de cette association peut provoquer des problèmes de stérilité ou des anomalies chromosomiques majeures. La formation des bivalents s’accompagne d’une dynamique chromosomique caractéristique, impliquant leur ancrage à l’enveloppe nucléaire et des mouvements intenses au sein du nucléoplasme. Dans une étude publiée dans Nature Plants, des scientifiques de l’Institut Jean-Pierre Bourgin - Sciences du Végétal - IJPB (INRAE/AgroParisTech/UPSaclay, Versailles) ont identifié chez Arabidopsis thaliana, le complexe protéique transmembranaire qui permet cet accrochage des chromosomes à l’enveloppe nucléaire. Ce complexe est composé de plusieurs protéines de l’enveloppe nucléaire (protéines à domaines SUN constitutives et une protéine à domaine KASH spécifique de la méiose) ainsi que d’une kinésine méiotique, susceptible d’établir un lien avec les microtubules. L’absence de chacune de ces protéines aboutit à des défauts d’attachement des chromosomes à l’enveloppe nucléaire, à une absence complète de mouvement des chromosomes, à des défauts de formation des bivalents et à une stérilité marquée des plantes. Ces défauts ont été associés à des altérations profondes de la recombinaison méiotique, caractérisées par une distribution anormale des événements de recombinaison au sein du génome. Ces résultats représentent les premières données sur le mécanisme gouvernant la dynamique des chromosomes pendant la prophase méiotique des plantes. Ils ouvrent la voie à de nouvelles investigations qui devront élucider les régulations moléculaires précises de ce processus et déterminer dans quelle mesure ces mécanismes sont conservés entre espèces. Légende Figure : Attachement défectueux des télomères dans les mutants du complexe LINC méiotique. Les télomères sont représentés par des sphères roses (lorsqu’ils sont localisés à l’enveloppe nucléaire) ou bleues (lorsqu’ils se trouvent dans le nucléoplasme). Panneau du haut : méiocytes d’A. thaliana avec immunolocalisation des axes chromosomiques (en vert et violet). Panneau central : télomères. Panneau du bas : télomères, enveloppe nucléaire (grande sphère transparente) et nucléole (petite sphère). -> Contact : mathilde.grelon@inrae.fr
Via Life Sciences UPSaclay
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Scooped by
Saclay Plant Sciences
August 20, 5:09 AM
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Legume plants form specific organs on their root system, the nitrogen-fixing nodules, thanks to a symbiotic interaction with soil bacteria collectively named rhizobia. Rhizobia however do not only induce the formation of these nodule organs, but also modulate root system architecture. In a new study published in Current Biology by the F. Frugier SILEG team, we identified in the Medicago truncatula model legume a previously unnoticed increase of the root stele diameter occurring upon rhizobium inoculation. This symbiotic root response, similarly observed in another crop legume, pea, occurs rapidly and locally after rhizobium inoculation, leading to an increased number of vascular cells. Interestingly, this root stele diameter symbiotic response requires Tracheary Element Differentiation Inhibitory Factor (TDIF) signaling peptides, and notably the MtCLE37 TDIF-encoding gene which expression is increased during nodulation, thus being referred to as symbiotic nodulation TDIF (sTDIF). Indeed, a cle37/stdif mutant is not responsive to rhizobium regarding its root stele diameter increase, and has a reduced nodule number. Combined transcriptomic and metabolomic analyses revealed that stdif has a defective primary metabolism, notably affecting carbohydrate/sugar accumulation in both roots and nodules. Remarkably, a sucrose or a malate exogenous treatment is able to rescue the rhizobium-induced stele diameter symbiotic response in stdif. This metabolic deregulation is thus instrumental in explaining the altered symbiotic response of the mutant. Overall, this study highlights a novel function of TDIF signaling peptides in legumes plants, which beyond regulating stele development, also modulate the root primary metabolism adaptations required for symbiotic nodule development. Contact: florian.frugier@cnrs.fr
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Rescooped by
Saclay Plant Sciences
from Plant Sciences
June 15, 4:09 AM
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This Summer School is organized by the Saclay Plant Sciences (SPS) network, one of the largest European plant sciences communities, and will be hosted by the cytology and imaging platform of the Institut Jean Pierre Bourgin - Plant Sciences in Versailles. Microscopy is a fundamental tool for understanding the functioning of plants at the cellular to molecular scale. Recent technological advances (super-resolution, fluorescence lifetime imaging, biosensors...) now make it possible to address new scientific questions. This Summer School will provide theoretical and practical insights into these aspects for 20 outstanding and enthusiastic PhD students or young postdoctoral researchers divided in small groups. Participants will have the opportunity to discuss the advantages and disadvantages of different modalities, sample preparation, image acquisition, and data processing throughout the week. The Summer School will include:
> A set of theoretical lectures (~9 hours) on the major issues in advanced imaging. The lectures will be given by experts in the field, who will be available for discussions during the Summer School, giving the participants an insight into the latest research findings and identifying key open questions in the field.
> A set of practical sessions (~24 hours + Restitution) to tackle real-life approaches on plant samples and compare different modalities of conventional confocal microscopy, super-resolution and fluorescence lifetime analysis. All Summer School participants will have access to all practical sessions, in groups of 3 or 4, with one (or more) expert per system. Given the advanced technologies covered, the Summer School is aimed at PhD students or young post-docs who already have practical experience in confocal microscopy. At the end of the Summer School, the experiences of all participants will be confronted in a general discussion, to expose the differences and possible advantages of the imaging technologies approached.
> Participant flash-talks and poster session (5 hours)
> Social activities This intensive and varied one-week program will allow many opportunities to discuss with speakers and fellow participants. Deadline for application: March 4, 2025 (midnight)
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Scooped by
Saclay Plant Sciences
June 1, 1:39 PM
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"Adzuki is a central legume in East Asian culinary culture, yet its domestication origin remains debated. Using ~700 accessions across Asia, we show that the initial domestication happened three to five thousand years ago in central Japan during the Jomon period, followed by a range expansion into China and secondary hybridization with Chinese wild populations. We mapped, validated, and dated key genes associated with seed coat color evolution (VaPAP1 for loss of mottled black and VaANR1 for gain of red colors). The frequency increases of variants affecting key domestication syndrome substantially predated the wild-cultigen divergence. Together, our results resolve the conflict between genetic and archaeological evidence about adzuki origins and reconstruct the evolutionary trajectory of archaeobotanically unobservable traits, consistent with a role of early weak selection during domestication"
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Scooped by
Saclay Plant Sciences
May 31, 12:34 PM
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