Hydrogen/deuterium exchange coupled to mass spectrometry in structural proteomics

Ce travail de thèse porte sur développement de méthodes en spectrométrie de masse structurale pour l’analyse de protéines recombinantes et de leurs complexes associés. L’objectif central s’est porté sur des développements méthodologiques en échange hydrogène/deutérium couplé à la spectrométrie de masse (HDX-MS). Les techniques biophysiques de caractérisation structurale à haute résolution comme la cristallographie ou la RMN se heurtent régulièrement à des problèmes de productions de cristaux, de taille de complexes analysables ou encore de quantité de matériel nécessaire importante. Le développement de méthodes spécifiques HDX-MS a permis de réaliser une caractérisation structurale de systèmes protéiques variés, et réfractaires aux approches haute résolution. La combinaison de cette approche à différents outils de MS structurale est aussi illustrée, et montre tout son intérêt pour l’obtention d’informations à résolution augmentée.This thesis work focuses on development of structural mass spectrometry methods for the analysis of recombinant proteins and their associated complex. The central objective has focused on the development of hydrogen/deuterium exchange coupled to mass spectrometry approaches (HDX-MS). The high resolution biophysical techniques for structural characterization such as crystallography or NMR regularly face problems of crystal productions, size analyzable complex or quantity of material required. The development of specific HDX-MS methods allowed the characterization of various, and refractory protein systems to high resolution approaches. The combination of this approach with complementary structural MS tools is also illustrated, and shows its interest to obtain increased resolution information

Apports de l'échange hydrogène/deutérium couplé à la spectrométrie de masse en protéomique structurale pour la caractérisation de complexes multi-protéiques.

This thesis work focuses on development of structural mass spectrometry methods for the analysis of recombinant proteins and their associated complex. The central objective has focused on the development of hydrogen/deuterium exchange coupled to mass spectrometry approaches (HDX-MS). The high resolution biophysical techniques for structural characterization such as crystallography or NMR regularly face problems of crystal productions, size analyzable complex or quantity of material required. The development of specific HDX-MS methods allowed the characterization of various, and refractory protein systems to high resolution approaches. The combination of this approach with complementary structural MS tools is also illustrated, and shows its interest to obtain increased resolution information.Ce travail de thèse porte sur développement de méthodes en spectrométrie de masse structurale pour l’analyse de protéines recombinantes et de leurs complexes associés. L’objectif central s’est porté sur des développements méthodologiques en échange hydrogène/deutérium couplé à la spectrométrie de masse (HDX-MS). Les techniques biophysiques de caractérisation structurale à haute résolution comme la cristallographie ou la RMN se heurtent régulièrement à des problèmes de productions de cristaux, de taille de complexes analysables ou encore de quantité de matériel nécessaire importante. Le développement de méthodes spécifiques HDX-MS a permis de réaliser une caractérisation structurale de systèmes protéiques variés, et réfractaires aux approches haute résolution. La combinaison de cette approche à différents outils de MS structurale est aussi illustrée, et montre tout son intérêt pour l’obtention d’informations à résolution augmentée

Hydrogen/deuterium exchange coupled to mass spectrometry in structural proteomics

Ce travail de thèse porte sur développement de méthodes en spectrométrie de masse structurale pour l’analyse de protéines recombinantes et de leurs complexes associés. L’objectif central s’est porté sur des développements méthodologiques en échange hydrogène/deutérium couplé à la spectrométrie de masse (HDX-MS). Les techniques biophysiques de caractérisation structurale à haute résolution comme la cristallographie ou la RMN se heurtent régulièrement à des problèmes de productions de cristaux, de taille de complexes analysables ou encore de quantité de matériel nécessaire importante. Le développement de méthodes spécifiques HDX-MS a permis de réaliser une caractérisation structurale de systèmes protéiques variés, et réfractaires aux approches haute résolution. La combinaison de cette approche à différents outils de MS structurale est aussi illustrée, et montre tout son intérêt pour l’obtention d’informations à résolution augmentée.This thesis work focuses on development of structural mass spectrometry methods for the analysis of recombinant proteins and their associated complex. The central objective has focused on the development of hydrogen/deuterium exchange coupled to mass spectrometry approaches (HDX-MS). The high resolution biophysical techniques for structural characterization such as crystallography or NMR regularly face problems of crystal productions, size analyzable complex or quantity of material required. The development of specific HDX-MS methods allowed the characterization of various, and refractory protein systems to high resolution approaches. The combination of this approach with complementary structural MS tools is also illustrated, and shows its interest to obtain increased resolution information

On the origins and domestication of the olive: a review and perspectives (vol 121, pg 385, 2018)

Erratum sur la notice: https://prodinra.inra.fr/record/428665International audienc

Calcul du champ électromagnétique dans un système de cavités couplées

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Synaptic functions of type-1 cannabinoid receptors in inhibitory circuits of the anterior piriform cortex

In the olfactory system, the endocannabinoid system (ECS) regulates sensory perception and memory. A major structure involved in these processes is the anterior piriform cortex (aPC), but the impact of ECS signaling in aPC circuitry is still scantly characterized. Using ex vivo patch clamp experiments in mice and neuroanatomical approaches, we show that the two major forms of ECS-dependent synaptic plasticity, namely depolarization-dependent suppression of inhibition (DSI) and long-term depression of inhibitory transmission (iLTD) are present in the aPC. Interestingly, iLTD expression depends on layer localization of the inhibitory neurons associated with the expression of the neuropeptide cholecystokinin. Conversely, the decrease of inhibitory transmission induced by exogenous cannabinoid agonists or DSI do not seem to be impacted by these factors. Altogether, these results indicate that CB1 receptors exert an anatomically specific and differential control of inhibitory plasticity in the aPC, likely involved in spatiotemporal regulation of olfactory processes

Primary domestication and early uses of the emblematic olive tree: palaeobotanical, historical and molecular evidence from the Middle East

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699International audienceOur knowledge of the origins of olive tree domestication in the Middle East and on the processes governing its extension and persistence in different vegetation types from prehistory through antiquity to modern times derives from diverse sources, spanning the biological sciences to the humanities. Nonetheless, it lacks a robust overview that may lead to floating interpretations. This is especially true in the Middle East, considered as the cradle of agriculture, and where the evolutionary history of this emblematic tree is intertwined with that of civilizations. Olive fruit, oil and wood have been, since Prehistoric times, characteristic products of the lands bordering the Mediterranean Sea. In the domestic economy of these countries, the olive tree gradually became a traditional tree crop since the first oil extraction, through the emergence of regional commerce that accompanied the rise and fall of early Near-Middle Eastern urbanism, until the development of modern trade, with an oil production estimated at circa 3000000 tons per year. The rising importance of the olive tree in human life has turned the tree into an endless source of fascination in the Aegean and Eastern Mediterranean, a symbol and a sacred tree, widely cited in the Bibles, the Koran, and in ancient literature. Here we argue that advances in radiocarbon chronology, palaeobotany, genetics, and archaeology-history have profoundly refined the history of olive trees in the Middle East. This review shows that the heartland of primary olive domestication must be enlarged to the Levant and not only focus on the Jordan Valley. The domestication of the olive tree is a long and ongoing process, linked to the early production of oil and the development of the olive trade. We also suggest that the olive tree became a particular icon, a sacred tree, during the Biblical period in the Levant

A Multifunctional Hybrid Graphene and Microfluidic Platform to Interface Topological Neuron Networks

Abstract The nervous system is as complex as difficult to probe. Innovative tools reducing the network complexity and being able to interrogate neurons are crucial to better understand its function and organization. In this study, solution‐gated graphene field effect transistors (GFETs) are combined with multi‐compartment microfluidic platform for multimodal and long‐lasting recording of neuron electrical activity. The fluidic microchannels, somatic and synaptic chambers enable to define the neuron network topology, while the graphene devices provide localized, highly sensitive, and optically transparent sensing sites. Immunofluorescence staining assesses for the healthy state and outgrowth of neurons within the microfluidic circuit, while calcium imaging demonstrates the maturation and spontaneous activity of the designed network. The efficient cell‐sensor alignment obtained by the microfluidic circuit enables to reach the highest reported signal‐to‐noise ratio for single‐units detection with GFETs, revealing additional information that can remain hidden from recordings when using conventional microelectrode arrays. Thus, the combination of graphene sensors and microfluidic circuits leverages the advantages of two state‐of‐the‐art technologies for highly efficient sensing of model neural networks. Being fully transparent and therefore compatible with optogenetic tools and high‐resolution microscopy, this novel platform can provide a versatile lab‐on‐chip for diagnosis and treatment of tomorrow

Structural Analysis Of Protein Complex Involving Box C/D Snornp AssemblyFactor BCD1P And Histone Chaperone RTT106

International audienc

Maximal Fat Oxidation During Exercise Is Already Impaired in Pre-pubescent Children With Type 1 Diabetes Mellitus

International audienceObjective: We evaluated substrate utilization during submaximal exercise, together with glycemic responses and hormonal counter-regulation to exercise, in children with type 1 diabetes mellitus (T1DM). Methods: Twelve pre-pubescent children with T1DM and 12 healthy children were matched by sex and age. Participants completed a submaximal incremental exercise test to determine their fat and carbohydrate oxidation rates by indirect calorimetry. Levels of glycemia, glucagon, cortisol, growth hormone, noradrenaline, adrenaline, and insulin were monitored until 120 min post-exercise. Results: Absolute peak oxygen uptake (VO 2 peak) was significantly lower in the children with T1DM than in the healthy controls (1131.4 ± 102.5 vs. 1383.0 ± 316.6 ml.min −1 , p = 0.03). Overall carbohydrate and lipid oxidation rates were the same in the two groups, but for exercise intensities, higher than 50% of VO 2 peak, fat oxidation rate was significantly lower in the children with T1DM. The absolute maximal lipid oxidation rate was significantly lower in the T1DM children (158.1 ± 31.6 vs. 205.4 ± 42.1 mg.min −1 , p = 0.005), and they reached a significantly lower exercise power than the healthy controls (26.4 ± 1.2 vs. 35.4 ± 3.3 W, p = 0.03). Blood glucose responses to exercise were negatively correlated with pre-exercise blood glucose concentrations ( r = −0.67; p = 0.03). Conclusion: Metabolic and hormonal responses during sub-maximal exercise are impaired in young children with T1DM