A5040128199- Legume Nitrogen Fixing Symbiosis
- Plant nutrient uptake and metabolism
- Plant-Microbe Interactions and Immunity
- Plant Molecular Biology Research
- Plant Stress Responses and Tolerance
- Plant tissue culture and regeneration
- Metabolomics and Mass Spectrometry Studies
- Plant Reproductive Biology
- Agronomic Practices and Intercropping Systems
- Plant Micronutrient Interactions and Effects
- Soybean genetics and cultivation
- Advanced Proteomics Techniques and Applications
- Microbial Metabolic Engineering and Bioproduction
- Plant responses to water stress
- Nematode management and characterization studies
- Biochemical and Molecular Research
- Photosynthetic Processes and Mechanisms
- Neonatal Health and Biochemistry
- Amino Acid Enzymes and Metabolism
- Coastal wetland ecosystem dynamics
- ATP Synthase and ATPases Research
- Atmospheric and Environmental Gas Dynamics
- Polyamine Metabolism and Applications
- Lipid metabolism and biosynthesis
- Cassava research and cyanide
Université de Montpellier
2005-2022
Institut Agro Montpellier
2009-2022
Institut des Sciences des Plantes de Montpellier
2017-2022
Centre National de la Recherche Scientifique
2017-2022
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2022
Laboratoire des Symbioses Tropicales et Méditerranéennes
2004-2017
Institut de Recherche pour le Développement
2008-2017
Centre de Coopération Internationale en Recherche Agronomique pour le Développement
2008-2017
Institut National de la Recherche Agronomique
1998-2013
Max Planck Institute of Molecular Plant Physiology
2002-2006
Summary Research on legume nodule metabolism has contributed greatly to our knowledge of primary carbon and nitrogen in plants general, symbiotic fixation particular. However, most previous studies focused one or a few genes/enzymes involved selected metabolic pathways many different species. We utilized the tools transcriptomics metabolomics obtain an unprecedented overview differentiation that results from development model legume, Lotus japonicus . Using array more than 5000 cDNA clones,...
Symbiotic nitrogen fixation (SNF) by intracellular rhizobia within legume root nodules requires the exchange of nutrients between host plant cells and their resident bacteria. Little is known at molecular level about transporters that mediate such exchanges. Several mutants model Lotus japonicus have been identified develop with metabolic defects cannot fix efficiently exhibit retarded growth under symbiotic conditions. Map-based cloning defective genes in two mutants, sst1-1 sst1-2 (for...
Symbiotic nitrogen fixation (SNF) in legume root nodules requires differentiation and integration of both plant bacterial metabolism. Classical approaches biochemistry, molecular biology, genetics have revealed many aspects primary metabolism that underpin SNF. Functional genomics approaches, especially transcriptomics proteomics, are beginning to provide a more holistic picture the metabolic potential model legumes like Medicago truncatula Lotus japonicus. To extend these we established...
Summary Disruption of the TRH1 potassium transporter impairs root hair development in Arabidopsis , and also affects gravitropic behaviour. Rescue these morphological defects by exogenous auxin indicates a link between activity transport. In agreement with this hypothesis, rate translocation from shoots to roots efflux [ 3 H]IAA isolated segments were reduced trh1 mutant, but radiolabelled was accelerated yeast cells transformed gene. roots, Pro TRH 1 : GUS expression localized cap which are...
Summary The Phyllobacterium brassicacearum STM 196 strain stimulates Arabidopsis thaliana growth and antagonizes high nitrate inhibition of lateral root development. A previous study identified two 196‐responsive genes, NRT 2.5 2.6 (Mantelin et al ., 2006, Planta 223: 591–603). We investigated the role in plant response to using single double mutants. mutants were also crossed with an nrt2.1 mutant, lacking major transporter, distinguish effects from potential indirect pools. nrt2.5 nrt2.6...
Induced systemic resistance (ISR) is a process elicited by telluric microbes, referred to as plant growth-promoting rhizobacteria (PGPR), that protect the host against pathogen attacks. ISR has been defined from studies using Pseudomonas strains biocontrol agent. Here, we show for first time photosynthetic Bradyrhizobium sp. strain, ORS278, also exhibits ability promote in Arabidopsis thaliana, indicating effect may be widespread ability. To investigate molecular bases of this response,...
Zinc is an essential micronutrient for all living organisms and involved in a plethora of processes including growth development, immunity. However, it unknown if there common genetic molecular basis underlying multiple facets zinc function. Here we used natural variation Arabidopsis thaliana to study the role regulating growth. We identify allelic systemic immunity gene AZI1 as key determining root responses low conditions. further demonstrate that this important modulating primary length...
Using their 1 amino cyclopropane-1-carboxylic acid (ACC) deaminase activity, many rhizobacteria can divert ACC from the ethylene biosynthesis pathway in plant roots. To investigate role of this microbial activity responses to growth-promoting (PGPR), we analyzed effects acdS knock-out and wild-type PGPR strains on two phenotypic inoculation –root hair elongation root system architecture– Arabidopsis thaliana. Our work shows that rhizobacterial AcdS has a negative effect elongation, as...
Establishment of symbiotic nitrogen-fixation in legumes is regulated by the plant hormone ethylene, but it has remained unclear whether and how its biosynthesis pathway. We established a sensitive ethylene detection system for Lotus japonicus found that production increased as early 6 hours after inoculation with Mesorhizobium loti. This response was dependent on Nod factor compatible rhizobia. Analyses nodulation mutants showed perception required emission, while downstream transcription...
TRH1 is a member of the AtKT/AtKUP/AtHAK family potassium carriers that required for root hair elongation and AKT1 an inward rectifying channel expressed in epidermis, endodermis cortex Arabidopsis thaliana. Plants homozygous trh1-1 mutation form short hairs. The Trh1(-) phenotype cannot be suppressed by growing plants presence high external KCl concentration. This indicates absolute requirement tip growth. akt1-1 develop longer hairs than wild type when grown 0 mM potassium, but shorter...
Fluorescent proteins (FPs) have given access to a large choice of live imaging techniques and has thereby profoundly modified our view plant cells. Together with technological improvement imaging, they opened the possibility monitor physico-chemical changes within For this purpose, new generation fluorescent been engineered. instance, pHluorin, point mutated version GFP, allows get local pH estimates. In paper, we will describe how genetically encoded sensors can be used measure in...
Fluorescent pseudomonads are playing key roles in plant-bacteria symbiotic interactions due to the multiple plant-beneficial functions (PBFs) they harboring. The relative contributions of PBFs plant-stimulatory effects well-known plant growth-promoting rhizobacteria Pseudomonas kilonensis F113 (formerly P. fluorescens F113) were investigated using a genetic approach. To this end, several deletion mutants constructed, simple ΔphlD (impaired biosynthesis 2,4-diacetylphloroglucinol [DAPG]),...
An antimonide distributed feedback quantum wells diode laser operating at 3.32 μm near room temperature in the continuous wave regime has been used to perform ethylene detection based on quartz enhanced photoacoustic spectroscopy. absorption line centered 3007.52 cm−1 was investigated and a normalized noise equivalent coefficient (1σ) of 3.09 10−7 W Hz−1/2 obtained. The linearity stability have evaluated. Biological samples’ respiration measured validate feasibility setup an agronomic...
Numerous reports have shown that various rhizobia can interact with non-host plant species, improving mineral nutrition and promoting growth. To further investigate the effects of such interactions on root development functions, we inoculated Arabidopsis thaliana model nitrogen fixing rhizobacterium Mesorhizobium loti (strain MAFF303099). In vitro, show colonization by M. remains epiphytic cells preferentially grow at sites where primary secondary roots intersect. Besides resulting in an...
The KUP family of potassium transporters in plants is large but poorly characterized. We isolated and characterized the first transporter from a legume, LjKUP Lotus japonicus. Although expressed throughout plants, transcript levels were highest nodules. Induction expression occurred late during nodule development, at time rapid organ expansion. A high level was maintained mature, full-sized However, induction independent symbiotic nitrogen fixation (SNF), ineffective nodules resulting...
Putrescine and other polyamines are produced by two alternative pathways in plants. One pathway starts with the enzyme arginine decarboxylase (ADC; EC 4.1.1.19), ornithine (ODC; 4.1.1.17). Metabolite profiling of nitrogen-fixing Lotus japonicus nodules, using gas chromatography coupled to mass spectrometry, revealed a two- sixfold increase putrescine levels mature nodules compared organs. Genes involved polyamine biosynthesis L. were identified isolating cDNA clones encoding ADC (LjADC1) ODC...
Phyllobacterium brassicacearum STM196, a plant growth-promoting rhizobacterium isolated from roots of oilseed rape, stimulates Arabidopsis growth. We have previously shown that the NRT2.5 and NRT2.6 genes are required for this growth promotion response. Since these members NRT2 family nitrate transporters, nitrogen assimilatory pathway could be involved in by STM196. address hypothesis using two reductase mutants, G5 deleted major gene NIA2 G'4-3 altered both NIA1 genes. Both mutants had...