A5070984468- Photosynthetic Processes and Mechanisms
- Plant responses to elevated CO2
- Plant Water Relations and Carbon Dynamics
- Plant nutrient uptake and metabolism
- Isotope Analysis in Ecology
- Plant Stress Responses and Tolerance
- Sunflower and Safflower Cultivation
- Oil Palm Production and Sustainability
- Soil Carbon and Nitrogen Dynamics
- Crop Yield and Soil Fertility
- Metal-Catalyzed Oxygenation Mechanisms
- Glutathione Transferases and Polymorphisms
- Microstructure and Mechanical Properties of Steels
- ATP Synthase and ATPases Research
- African Botany and Ecology Studies
- Tree-ring climate responses
- Irrigation Practices and Water Management
- Geology and Paleoclimatology Research
- Corrosion Behavior and Inhibition
- Mitochondrial Function and Pathology
- Plant Physiology and Cultivation Studies
- Light effects on plants
- Atmospheric chemistry and aerosols
- Force Microscopy Techniques and Applications
- Conservation, Biodiversity, and Resource Management
Université Paris-Saclay
2015-2024
Institut de Biologie Intégrative de la Cellule
2024
Centre National de la Recherche Scientifique
2011-2024
CEA Paris-Saclay
2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2024
Institut des Sciences des Plantes de Paris Saclay
2010-2022
Université Paris-Sud
2011-2019
Sorbonne Paris Cité
2016
Université Paris Cité
2016
Centre Technique des Industries Mécaniques
1986
Although there is now a considerable literature on the inhibition of leaf respiration (CO(2) evolution) by light, little known about effect other environmental conditions day respiratory metabolism. In particular, CO(2) and O(2) mole fractions are assumed to cause changes in tricarboxylic acid pathway (TCAP) but amplitude even direction such still matter debate. Here, we took advantage isotopic techniques, new simple equations instant freeze sampling follow metabolism illuminated cocklebur...
Metabolic and physiological analyses of glutamate:glyoxylate aminotransferase 1 (GGT1) mutants were performed at the global leaf scale to elucidate mechanisms involved in their photorespiratory growth phenotype. Air-grown ggt1 showed retarded development, that was not observed high CO2 (3000 μL L(-1) ). When compared wild-type (WT) plants, air-grown plants exhibited glyoxylate accumulation, changes amino acid amounts including a decrease serine content, lower organic levels, modified ATP/ADP...
Abstract The photorespiratory cycle is a crucial pathway in photosynthetic organisms because it removes toxic 2‐phosphoglycolate made by the oxygenase activity of ribulose‐1,5‐bisphosphate carboxylase/oxygenase and retrieves its carbon as 3‐phosphoglycerate. Mitochondrial serine hydroxymethyltransferase 1 (SHMT1) an essential enzyme converting glycine to serine. SHMT1 regulation remains poorly understood although could involve phosphorylation 31. Here, we report complementation Arabidopsis...
Nitrogen isotope composition (δ(15) N) in plant organic matter is currently used as a natural tracer of nitrogen acquisition efficiency. However, the δ(15) N value whole leaf material does not properly reflect way which assimilated because fractionations along metabolic reactions may cause substantial differences among compounds. In other words, any change or allocation pattern undesirable variability N. Here, we investigated different fractions and individual metabolites from rapeseed...
ABSTRACT In leaves, although it is accepted that CO 2 evolved by dark respiration after illumination naturally 13 C‐enriched compared to organic matter or substrate sucrose, much uncertainty remains on whether day produces C‐depleted . Here, we applied equations described previously for mesocosm exchange investigate the carbon isotope composition of respired autotrophic and heterotrophic tissues Pelargonium × hortorum taking advantage leaf variegation. Day‐respired was slightly both under...
Leaf intrinsic water-use efficiency (WUE), the ratio of photosynthetic rate to stomatal conductance (A/g(s) ), is a key plant trait linking terrestrial carbon and water cycles. A rapid, integrative proxy for A/g(s) benefit crop breeding programmes aiming improve WUE, but also ecologists interested in carbon-water balance natural systems. We hypothesize that isotope composition leaf-respired CO(2) (δ(13) C(Rl) two hours after leaves are transferred dark, records discrimination so provides ....
Abstract Oil palm has now become one of the most important crops, oil representing nearly 25% global plant consumption. Many studies have thus addressed ecophysiology and photosynthesis‐based models carbon allocation been used. However, there is a lack experimental data on fixation redistribution within trees, C‐sinks not fully characterized yet. Here, we carried out extensive measurement natural 13 C‐abundance ( δ C) in tissues, including fruits at different maturation stages. We find...
Plant mutants for genes encoding subunits of mitochondrial complex I (CI; NADH:ubiquinone oxidoreductase), the first enzyme respiratory chain, display various phenotypes depending on growth conditions. Here, we examined impact photoperiod, a major environmental factor controlling plant development, two Arabidopsis (Arabidopsis thaliana) CI mutants: new insertion mutant interrupted in both ndufs8.1 and ndufs8.2 NDUFS8 subunit previously characterized ndufs4 mutant. In long day (LD) condition,...
Many horticultural and natural plant species have variegated leaves, that is, patchy leaves with green non-green or white areas. Specific studies on the metabolism of are scarce although (non-green) areas been assumed to play role a 'nitrogen store', there is no specific showing analysis nitrogenous metabolites dynamics nitrogen assimilation. Here, we examined Pelargonium×hortorum. We show larger N:C ratio, more amino acids, clear accumulation arginine. Metabolomic analyses revealed...
Variegation (patchy surface area with different colours) is a common trait of plant leaves. In green-white variegated leaves, two tissues contrasted primary carbon metabolisms (autotrophic in green and heterotrophic white tissues) are juxtaposed. It generally believed that variegation detrimental to growth due the lower photosynthetic area. However, occurrence leaf nature raises question possible advantage under certain circumstances. Here, we examined metabolism Pelargonium × hortorum...
Carbon isotope composition in respired CO2 and organic matter of individual organs were measured on peanut seedlings during early ontogeny order to compare fractionation heterotrophic growth transition autotrophy a species with lipid seed reserves earlier results obtained beans. Despite high content seeds (48 %) compared bean (1.5 %), the leaf- root-respired as well its changes similar already published data seedlings: leaf-respired became 13C-enriched reaching −21.5 ‰, while 13C-depleted...
Abstract The natural 13 C abundance (δ C) in plant leaves has been used for decades with great success agronomy to monitor water‐use efficiency and select modern cultivars adapted dry conditions. However, wheat, it is also important find genotypes high carbon allocation spikes grains, thus a harvest index (HI) and/or low losses via respiration. Finding isotope‐based markers of partitioning grains would be extremely useful since isotope analyses are inexpensive can performed routinely at...
The issues of whether, where, and to what extent carbon isotopic fractionations occur during respiration affect interpretations plant functions that are important many disciplines across the natural sciences. Studies fractionation dark in C3 plants have repeatedly shown respired CO2 be 13C enriched relative its bulk leaf sources depleted root sources. Furthermore, two studies showed become progressively ontogeny legumes. As such data on C4 scarce contradictory, we investigated apparent...
Many plant species or cultivars form variegated leaves in which blades are made of green and white sectors. On the one hand, there is little photosynthetic CO2 assimilation tissue simply because lack functional chloroplasts thus, leaf heterotrophic fed by photosynthates exported tissue. other it has been previously shown that enriched nitrogenous compounds such as amino acids polyamines, can, turn, be remobilised upon nitrogen deficiency. However, origin organic tissue, including possible...
Abstract Despite the high economic value of safflower ( Carthamus tinctorius ), potential several wild related species as genetic resources is still poorly studied, in particular with regards to drought tolerance, a priority improvement. This situation partially explained by numerous and discussed uncertainties phylogenetic relationships within complex. In this study, we focused on two rare Algerian species, strictus chouletteanus . We aimed at: (i) clarifying their taxonomic status,...
The goals of the present study were to obtain a first estimate intraspecific variability carbon isotope discrimination (Δ) in safflower, thistle-like herbaceous plant, and determine statistical relationship between Δ grain yield as well its components collection 45 accessions different origins. Grain aboveground biomass, harvest index, average weight, (measured on bulk leaf organic matter) investigated experimental field conditions. A large was noted for all traits but principal component...
Glutathione S-transferases (GSTs) are evolutionarily conserved enzymes crucial for cell detoxication. They viewed as having evolved in cyanobacteria, the ancient photosynthetic prokaryotes that colonize our planet and play a role its biosphere. Xi-class GSTs, characterized by their specific glutathionyl–hydroquinone reductase activity, have been observed prokaryotes, fungi plants, but not yet studied cyanobacteria. In this study, we analyzed presumptive GST, designated Slr0605, of...
The natural 13C abundance (δ13C) in plant leaves has been used for decades with great success agronomy to monitor water use efficiency and select modern cultivars adapted dry conditions. However, wheat, breeding also implies looking genotypes high carbon allocation spikes grains, thus a harvest index and/or low losses via respiration. Finding isotope-based markers of optimal partitioning grains would be extremely useful since isotope analyses are inexpensive can performed routinely at...
The purpose of this study was to determine what extent root characteristics, other than the taproot length, contribute high grain yield and/or water use efficiency (WUE) in safflower. A greenhouse trial conducted using four safflower accessions (USDA6, USDA23, USDA29 and VARTOUG) with contrasting WUE. randomised complete block design chosen, which included a typical (control) drought stress (withholding watering at pre-flowering stage) treatments. carbon isotope composition (δ13C) as an...