A5002388673- Plant nutrient uptake and metabolism
- Legume Nitrogen Fixing Symbiosis
- Diatoms and Algae Research
- Protist diversity and phylogeny
- Marine and coastal ecosystems
- Algal biology and biofuel production
- Plant Molecular Biology Research
- Microbial Community Ecology and Physiology
- Photosynthetic Processes and Mechanisms
- Genomics and Phylogenetic Studies
- Nematode management and characterization studies
- Plant Stress Responses and Tolerance
- Agronomic Practices and Intercropping Systems
- Advanced biosensing and bioanalysis techniques
- Polymer-Based Agricultural Enhancements
- Wastewater Treatment and Nitrogen Removal
- Light effects on plants
- Soybean genetics and cultivation
- Microbial Metabolic Engineering and Bioproduction
- Potato Plant Research
- Gold and Silver Nanoparticles Synthesis and Applications
- Cholinesterase and Neurodegenerative Diseases
- Photoreceptor and optogenetics research
- Electrochemical sensors and biosensors
- Plant tissue culture and regeneration
Institute of Biosciences and Bioresources
2015-2024
National Research Council
2018-2023
Stazione Zoologica Anton Dohrn
2009-2023
Centre National de la Recherche Scientifique
2009-2016
Laboratoire de Biologie Computationnelle et Quantitative
2016
Sorbonne Université
2010-2014
Université Paris Cité
2014
Institute of Genetics and Biophysics
2004-2012
University of Konstanz
2012
LIttoral ENvironnement et Sociétés
2012
Diatoms are a major but poorly understood phytoplankton group. The recent completion of two whole genome sequences has revealed that they contain unique combinations genes, likely recruited during their history as secondary endosymbionts, well by horizontal gene transfer from bacteria. A limitation for the study diatom biology and function is lack tools to generate targeted knockout or knockdown mutants. In this work, we have assessed possibility triggering silencing in Phaeodactylum...
Diatoms are prominent phytoplanktonic organisms that contribute around 40% of carbon assimilation in the oceans. They grow and perform optimally variable environments, being able to cope with unpredictable changes amount quality light. The molecular mechanisms regulating diatom light responses are, however, still obscure. Using knockdown Phaeodactylum tricornutum transgenic lines, we reveal key function a member light-harvesting complex stress-related (LHCSR) protein family, denoted LHCX1,...
Abstract In diatoms, the process of energy-dependent chlorophyll fluorescence quenching (qE) has an important role in photoprotection. Three components are essential for qE: (1) light-dependent generation a transthylakoidal proton gradient; (2) deepoxidation xanthophyll diadinoxanthin (Dd) into diatoxanthin (Dt); and (3) specific nucleus-encoded antenna proteins, called Light Harvesting Complex Protein X (LHCX). We used model diatom Phaeodactylum tricornutum to investigate concerted light...
Diatoms are phytoplanktonic organisms that grow successfully in the ocean where light conditions highly variable. Studies of molecular mechanisms acclimation marine diatom Phaeodactylum tricornutum show carotenoid de-epoxidation enzymes and LHCX1, a member light-harvesting protein family, both contribute to dissipate excess energy through non-photochemical quenching (NPQ). In this study, we investigate role other members LHCX family stress responses. Our analysis available genomic data shows...
Diatoms contain a highly flexible capacity to dissipate excessively absorbed light by nonphotochemical fluorescence quenching (NPQ) based on the light-induced conversion of diadinoxanthin (Dd) into diatoxanthin (Dt) and presence Lhcx proteins. Their NPQ fine regulation molecular level upon shift dynamic conditions is unknown. We investigated Dd + Dt amount, gene protein synthesis in diatom Phaeodactylum tricornutum after change from continuous low 3 d sine (SL) or fluctuating (FL)...
Abstract Diatoms are prominent and highly diverse microalgae in aquatic environments. Compared with other diatom species, Phaeodactylum tricornutum is an “atypical diatom” displaying three different morphotypes lacking the usual silica shell. Despite being of limited ecological relevance, its ease growth laboratory well‐known physiology, alongside steady increase genome‐enabled information coupled effective tools for manipulating gene expression, have meant it has gained increased...
Abstract Plants respond to changes of nutrient availability in the soil by modulating their root system developmental plan. This response is mediated systemic nutritional status and/or local perception specific signals. The effect nitrate on Arabidopsis (Arabidopsis thaliana) development represents a paradigm these responses, and transporters are involved both control. Ammonium (NH4 +) an important nitrogen (N) source for plants, although toxicity symptoms often associated with high NH4 +...
In this work, we propose the use of complex, bioderived nanostructures as efficient surface-enhanced Raman scattering (SERS) substrates for chemical analysis cellular membranes. These structures were directly obtained from a suitable gold metalization Pseudonitzchia multistriata diatom silica shell (the so called frustule), whose grating-like geometry provides large light coupling with external radiation, whereas its extruded, subwavelength lateral edge an excellent interaction cells without...
Abstract Ammonium is a primary source of nitrogen for plants. In legume plants ammonium can also be obtained by symbiotic fixation, and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\mathrm{NH}_{4}^{{+}}\) \end{document} regulator early late interaction steps. transporters are likely to play important roles in the control nodule formation as well assimilation. Two new genes,...
The development of nitrogen-fixing nodules in legumes is induced by perception lipochitin-oligosaccharide signals secreted a bacterial symbiont. Nitrogen (N) starvation prerequisite for the formation, development, and function root nodules, high levels combined N form nitrate or ammonium can completely abolish nodule formation. We distinguished between inhibitory effects identifying when where these sources interfere with Nod-factor-induced pathway. Furthermore, we present small-scale...
N-fixing nodules are new organs formed on legume roots as a result of the beneficial interaction with soil bacteria, rhizobia. The nodule functioning is still poorly characterized step symbiotic interaction, only few genes induced in have been functionally characterized. We present here characterization member Lotus japonicus nitrate transporter1/peptide transporter family, LjNPF8.6. phenotypic carried out independent L. LORE1 insertion lines indicates positive role LjNPF8.6 functioning,...
Summary Atmospheric nitrogen (N 2) ‐fixing nodules are formed on the roots of legume plants as result symbiotic interaction with rhizobia. Nodule functioning requires high amounts carbon and energy, therefore legumes have developed finely tuned mechanisms to cope changing external environmental conditions, including nutrient availability flooding. The investigation role nitrate regulator N 2 fixation has been limited inhibitory effects exerted by concentrations nodule formation, development...
Marine diatoms constitute a major component of eukaryotic phytoplankton and stand at the crossroads several evolutionary lineages. These microalgae possess peculiar genomic features novel combinations genes acquired from bacterial, animal plant ancestors. Furthermore, they display both DNA methylation gene silencing activities. Yet, biogenesis regulatory function small RNAs (sRNAs) remain ill defined in diatoms. Here we report first comprehensive characterization sRNA landscape its...
Dormancy is widespread in both multicellular and unicellular organisms. Among diatoms, microalgae at the base of all aquatic food webs, several species produce dormant cells (spores or resting cells) that can withstand long periods adverse environmental conditions.We present first gene expression study during process spore formation induced by nitrogen depletion marine planktonic diatom Chaetoceros socialis. In this condition, genes related to photosynthesis nitrate assimilation, including...
Diatoms (Bacillariophyta), one of the most abundant and diverse groups marine phytoplankton, respond rapidly to supply new nutrients, often out-competing other phytoplankton. Herein, we integrated analyses evolution, distribution, expression modulation two gene families involved in diatom nitrogen uptake (DiAMT1 DiNRT2), order infer main drivers divergence a key functional trait Our results suggest that major steps evolution reflected events triggering radiation diversification. Their is...
Diatom frustules represent one of the most complex examples micro- and nano-structured materials found in nature, being result a biomineralization process refined through tens milions years evolution. They are constituted by an intricate, ordered porous silica matrix which recently several applications optoelectronics, sensing, solar light harvesting, filtering, drug delivery, to name few. The possibility modify composition structure can further broaden range potential applications, adding...
• In leguminous plants, symbiotic nitrogen (N) fixation performances and N environmental conditions are linked because nodule initiation, development functioning greatly influenced by the amount of available sources. We demonstrate here that supply also controls, beforehand, competence plants to perform nodulation program. Lotus japonicus preincubated for 10 d in high-N conditions, then transferred low before Mesorhizobium loti inoculation, had reduced nodulation. This phenotype was...
Plant ammonium transporters of the AMT1 family are involved in N-uptake from soil and transport, recycling within plant. Although genes known to be expressed nitrogen-fixing nodules legumes, their precise roles this specialized organ remain unknown. We have taken a reverse-genetic approach decipher physiological role LjAMT1;1 Lotus japonicus nodules. is normally both infected zone vascular tissue Inhibition gene expression, using an antisense construct driven by leghemoglobin promoter...
Plant evolved a complex profile of responses to cope with changes nutrient availability in the soil. These are based on stringent control expression and/or activity proteins involved nutrients transport and assimilation. Furthermore, sensing signaling system for scanning concentration substrates rooted area transmitting this information plant machinery controlling root development can be extremely useful an efficient response. Ammonium represents plants either preferential nitrogen source or...
Carbonic anhydrases (CAs) are ubiquitous metalloenzymes, which started to be investigated in detail pathogenic, as well non-pathogenic species since their pivotal role is accelerate the physiological CO2 hydration/dehydration reaction significantly. Here, we propose marine unicellular diatom Phaeodactylum tricornutum a model organism for testing membrane penetrability of CA inhibitors (CAIs). Seven belonging sulphonamide type and possessing diverse scaffold have been explored vitro...