Search

Your search keyword '"Grélard, Axelle"' showing total 231 results
Start Over Author "Grélard, Axelle"
231 results on '"Grélard, Axelle"'

6. Biophysical analysis of the plant-specific GIPC sphingolipids reveals multiple modes of membrane regulation

Author

Cassim, Adiilah Mamode, Navon, Yotam, Gao, Yu, Decossas, Marion, Fouillen, Laetitia, Grélard, Axelle, Nagano, Minoru, Lambert, Olivier, Bahammou, Delphine, Van Delft, Pierre, Maneta-Peyret, Lilly, Simon-Plas, Françoise, Heux, Laurent, Jean, Bruno, Fragneto, Giovanna, Mortimer, Jenny C, Deleu, Magali, Lins, Laurence, and Mongrand, Sébastien

Subjects
Biochemistry and Cell Biology, Chemical Sciences, Biological Sciences, Biophysics, Cell Membrane, Plants, Polysaccharides, Species Specificity, Sphingolipids, GIPC, Langmuir monolayer, cryo-EM, modeling, neutron reflectivity, phytosterol, plasma membrane, solid-state NMR, sphingolipids, ζ-potential, Medical and Health Sciences, Biochemistry & Molecular Biology, Biological sciences, Biomedical and clinical sciences, Chemical sciences
Abstract

The plant plasma membrane (PM) is an essential barrier between the cell and the external environment, controlling signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols, and phospholipids. The glycosyl inositol phosphoryl ceramides (GIPCs), representing up to 40% of total sphingolipids, are assumed to be almost exclusively in the outer leaflet of the PM. However, their biological role and properties are poorly defined. In this study, we investigated the role of GIPCs in membrane organization. Because GIPCs are not commercially available, we developed a protocol to extract and isolate GIPC-enriched fractions from eudicots (cauliflower and tobacco) and monocots (leek and rice). Lipidomic analysis confirmed the presence of trihydroxylated long chain bases and 2-hydroxylated very long-chain fatty acids up to 26 carbon atoms. The glycan head groups of the GIPCs from monocots and dicots were analyzed by gas chromatograph-mass spectrometry, revealing different sugar moieties. Multiple biophysics tools, namely Langmuir monolayer, ζ-Potential, light scattering, neutron reflectivity, solid state 2H-NMR, and molecular modeling, were used to investigate the physical properties of the GIPCs, as well as their interaction with free and conjugated phytosterols. We showed that GIPCs increase the thickness and electronegativity of model membranes, interact differentially with the different phytosterols species, and regulate the gel-to-fluid phase transition during temperature variations. These results unveil the multiple roles played by GIPCs in the plant PM.

Published
2021

7. Biophysical analysis of the plant-specific GIPC sphingolipids reveals multiple modes of membrane regulation.

Author

Mamode Cassim, Adiilah, Navon, Yotam, Gao, Yu, Decossas, Marion, Fouillen, Laetitia, Grélard, Axelle, Nagano, Minoru, Lambert, Olivier, Bahammou, Delphine, Van Delft, Pierre, Maneta-Peyret, Lilly, Simon-Plas, Françoise, Heux, Laurent, Jean, Bruno, Fragneto, Giovanna, Mortimer, Jenny C, Deleu, Magali, Lins, Laurence, and Mongrand, Sébastien

Subjects
Cell Membrane, Plants, Polysaccharides, Sphingolipids, Biophysics, Species Specificity, GIPC, Langmuir monolayer, cryo-EM, modeling, neutron reflectivity, phytosterol, plasma membrane, solid-state NMR, sphingolipids, ζ-potential, Biochemistry & Molecular Biology, Chemical Sciences, Biological Sciences, Medical and Health Sciences
Abstract

The plant plasma membrane (PM) is an essential barrier between the cell and the external environment, controlling signal perception and transmission. It consists of an asymmetrical lipid bilayer made up of three different lipid classes: sphingolipids, sterols, and phospholipids. The glycosyl inositol phosphoryl ceramides (GIPCs), representing up to 40% of total sphingolipids, are assumed to be almost exclusively in the outer leaflet of the PM. However, their biological role and properties are poorly defined. In this study, we investigated the role of GIPCs in membrane organization. Because GIPCs are not commercially available, we developed a protocol to extract and isolate GIPC-enriched fractions from eudicots (cauliflower and tobacco) and monocots (leek and rice). Lipidomic analysis confirmed the presence of trihydroxylated long chain bases and 2-hydroxylated very long-chain fatty acids up to 26 carbon atoms. The glycan head groups of the GIPCs from monocots and dicots were analyzed by gas chromatograph-mass spectrometry, revealing different sugar moieties. Multiple biophysics tools, namely Langmuir monolayer, ζ-Potential, light scattering, neutron reflectivity, solid state 2H-NMR, and molecular modeling, were used to investigate the physical properties of the GIPCs, as well as their interaction with free and conjugated phytosterols. We showed that GIPCs increase the thickness and electronegativity of model membranes, interact differentially with the different phytosterols species, and regulate the gel-to-fluid phase transition during temperature variations. These results unveil the multiple roles played by GIPCs in the plant PM.

Published
2021

10. Cell-free synthesis of amyloid fibrils with infectious properties and amenable to sub-milligram magic-angle spinning NMR analysis

Author

Lends, Alons, Daskalov, Asen, Maleckis, Ansis, Delamare, Aline, Berbon, Mélanie, Grélard, Axelle, Morvan, Estelle, Shenoy, Jayakrishna, Dutour, Antoine, Tolchard, James, Noubhani, Abdelmajid, Giraud, Marie-France, Sanchez, Corinne, Habenstein, Birgit, Guichard, Gilles, Compain, Guillaume, Jaudzems, Kristaps, Saupe, Sven J., and Loquet, Antoine

Published
2022
Full Text
View/download PDF

14. Structural polymorphism of the low-complexity C-terminal domain of TDP-43 amyloid aggregates revealed by solid-state NMR

Author

Shenoy, Jayakrishna, primary, Lends, Alons, additional, Berbon, Mélanie, additional, Bilal, Muhammed, additional, El Mammeri, Nadia, additional, Bertoni, Mathilde, additional, Saad, Ahmad, additional, Morvan, Estelle, additional, Grélard, Axelle, additional, Lecomte, Sophie, additional, Theillet, François-Xavier, additional, Buell, Alexander K., additional, Kauffmann, Brice, additional, Habenstein, Birgit, additional, and Loquet, Antoine, additional

Published
2023
Full Text
View/download PDF

15. Structural polymorphism of the low-complexity C-terminal domain of TDP-43 amyloid aggregates revealed by solid-state NMR

Author

Shenoy, Jayakrishna, Lends, Alons, Berbon, Mélanie, Bilal, Muhammed, El Mammeri, Nadia, Bertoni, Mathilde, Saad, Ahmad, Morvan, Estelle, Grélard, Axelle, Lecomte, Sophie, Theillet, François Xavier, Buell, Alexander K., Kauffmann, Brice, Habenstein, Birgit, Loquet, Antoine, Shenoy, Jayakrishna, Lends, Alons, Berbon, Mélanie, Bilal, Muhammed, El Mammeri, Nadia, Bertoni, Mathilde, Saad, Ahmad, Morvan, Estelle, Grélard, Axelle, Lecomte, Sophie, Theillet, François Xavier, Buell, Alexander K., Kauffmann, Brice, Habenstein, Birgit, and Loquet, Antoine

Abstract

Aberrant aggregation of the transactive response DNA-binding protein (TDP-43) is associated with several lethal neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal dementia. Cytoplasmic neuronal inclusions of TDP-43 are enriched in various fragments of the low-complexity C-terminal domain and are associated with different neurotoxicity. Here we dissect the structural basis of TDP-43 polymorphism using magic-angle spinning solid-state NMR spectroscopy in combination with electron microscopy and Fourier-transform infrared spectroscopy. We demonstrate that various low-complexity C-terminal fragments, namely TDP-13 (TDP-43300–414), TDP-11 (TDP-43300–399), and TDP-10 (TDP-43314–414), adopt distinct polymorphic structures in their amyloid fibrillar state. Our work demonstrates that the removal of less than 10% of the low-complexity sequence at N- and C-termini generates amyloid fibrils with comparable macroscopic features but different local structural arrangement. It highlights that the assembly mechanism of TDP-43, in addition to the aggregation of the hydrophobic region, is also driven by complex interactions involving low-complexity aggregation-prone segments that are a potential source of structural polymorphism.

Published
2023

21. Solid-state NMR molecular snapshots of Aspergillus fumigatus cell wall architecture during a conidial morphotype transition

Author

Lamon, Gaëlle, primary, Lends, Alons, additional, Valsecchi, Isabel, additional, Wong, Sarah Sze Wah, additional, Duprès, Vincent, additional, Lafont, Frank, additional, Tolchard, James, additional, Schmitt, Christine, additional, Mallet, Adeline, additional, Grélard, Axelle, additional, Morvan, Estelle, additional, Dufourc, Erick J., additional, Habenstein, Birgit, additional, Guijarro, J. Iñaki, additional, Aimanianda, Vishukumar, additional, and Loquet, Antoine, additional

Published
2023
Full Text
View/download PDF

22. Supramolecular organization and dynamics of mannosylated phosphatidylinositol lipids in the mycobacterial plasma membrane

Author

Brown, Chelsea M., primary, Corey, Robin A., additional, Grélard, Axelle, additional, Gao, Ya, additional, Choi, Yeol Kyo, additional, Luna, Emanuel, additional, Gilleron, Martine, additional, Destainville, Nicolas, additional, Nigou, Jérôme, additional, Loquet, Antoine, additional, Fullam, Elizabeth, additional, Im, Wonpil, additional, Stansfeld, Phillip J., additional, and Chavent, Matthieu, additional

Published
2023
Full Text
View/download PDF

25. Membrane plasticity induced by myo-inositol derived archaeal lipids: chemical synthesis and biophysical characterization.

Author

Ruiz, Johal, LoRicco, Josephine G., Soulεave;re, Laurent, Castell, Marta Salvador, Grélard, Axelle, Kauffmann, Brice, Dufourc, Erick J., Demé, Bruno, Popowycz, Florence, and Peters, Judith

Abstract

Archaeal membrane lipids have specific structures that allow Archaea to withstand extreme conditions of temperature and pressure. In order to understand the molecular parameters that govern such resistance, the synthesis of 1,2-di-O-phytanyl-sn-glycero-3-phosphoinositol (DoPhPI), an archaeal lipid derived from myo-inositol, is reported. Benzyl protected myo-inositol was first prepared and then transformed to phosphodiester derivatives using a phosphoramidite based-coupling reaction with archaeol. Aqueous dispersions of DoPhPI alone or mixed with DoPhPC can be extruded and form small unilamellar vesicles, as detected by DLS. Neutron, SAXS, and solid-state NMR demonstrated that the water dispersions could form a lamellar phase at room temperature that then evolves into cubic and hexagonal phases with increasing temperature. Phytanyl chains were also found to impart remarkable and nearly constant dynamics to the bilayer over wide temperature ranges. All these new properties of archaeal lipids are proposed as providers of plasticity and thus means for the archaeal membrane to resist extreme conditions. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

26. Unraveling Membrane Perturbations Caused by the Bacterial Riboregulator Hfq

Author

Turbant, Florian, primary, Waeytens, Jehan, additional, Campidelli, Camille, additional, Bombled, Marianne, additional, Martinez, Denis, additional, Grélard, Axelle, additional, Habenstein, Birgit, additional, Raussens, Vincent, additional, Velez, Marisela, additional, Wien, Frank, additional, and Arluison, Véronique, additional

Published
2022
Full Text
View/download PDF

27. Unraveling Membrane Perturbations Caused by the Bacterial Riboregulator Hfq

Author

Turbant, Florian, Waeytens, Jehan, Campidelli, Camille, Bombled, Marianne, Martinez, Denis, Grélard, Axelle, Habenstein, Birgit, Raussens, Vincent, Vélez, Marisela, Wien, Frank, Arluison, Véronique, Turbant, Florian, Waeytens, Jehan, Campidelli, Camille, Bombled, Marianne, Martinez, Denis, Grélard, Axelle, Habenstein, Birgit, Raussens, Vincent, Vélez, Marisela, Wien, Frank, and Arluison, Véronique

Abstract

Hfq is a pleiotropic regulator that mediates several aspects of bacterial RNA metabolism. The protein notably regulates translation efficiency and RNA decay in Gram-negative bacteria, usually via its interaction with small regulatory RNAs. Previously, we showed that the Hfq C-terminal region forms an amyloid-like structure and that these fibrils interact with membranes. The immediate consequence of this interaction is a disruption of the membrane, but the effect on Hfq structure was unknown. To investigate details of the mechanism of interaction, the present work uses different in vitro biophysical approaches. We show that the Hfq C-terminal region influences membrane integrity and, conversely, that the membrane specifically affects the amyloid assembly. The reported effect of this bacterial master regulator on membrane integrity is discussed in light of the possible consequence on small regulatory RNA-based regulation., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2022

29. Quantitative T1D assessment in lipid membranes: Jeener-Broekaert NMR vs. ihMT MRI

Author

Hertanu, A., Soustelle, Lucas, de Rochefort, Ludovic, Grélard, Axelle, Dufourc, Erick J., Alsop, David, Duhamel, Guillaume, Girard, Olivier M., de Rochefort, Ludovic, Centre de résonance magnétique biologique et médicale (CRMBM), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Centre d'Exploration Métabolique par Résonance Magnétique [Hôpital de la Timone - APHM] (CEMEREM), Hôpital de la Timone [CHU - APHM] (TIMONE)-Centre de résonance magnétique biologique et médicale (CRMBM), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Division of MR Research, Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States

Subjects
[PHYS]Physics [physics], [SDV] Life Sciences [q-bio], [SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], [SDV]Life Sciences [q-bio], [PHYS] Physics [physics]
Abstract

International audience; The dipolar order relaxation time (T1D) is a probe of membrane dynamics and microstructure and could serve to further understand the relationship between the myelin membrane integrity and its biological function. In this work, the ability of quantitative inhomogeneous Magnetization Transfer (qihMT) to estimate the several T1D components of a synthetic lipid membrane system, a surrogate for the myelin membrane, was evaluated by comparison with the gold standard method for T1D quantification, the NMR Jeener-Broekaert (JB) sequence.

Published
2022

31. Mechanism of Trypanosoma brucei gambiense resistance to human serum

Author

Uzureau, Pierrick, Uzureau, Sophie, Lecordier, Laurence, Fontaine, Frédéric, Tebabi, Patricia, Homblé, Fabrice, Grélard, Axelle, Zhendre, Vanessa, Nolan, Derek P., Lins, Laurence, Crowet, Jean-Marc, Pays, Annette, Felu, Cécile, Poelvoorde, Philippe, Vanhollebeke, Benoit, Moestrup, Soren K., Lyngsø, Jeppe, Pedersen, Jan Skov, Mottram, Jeremy C., Dufourc, Erick J., Pérez-Morga, David, and Pays, Etienne

Published
2013
Full Text
View/download PDF

33. Bacteria associated with wood tissues of Esca‐diseased grapevines: functional diversity and synergy with Fomitiporia mediterranea to degrade wood components

Author

Haidar, Rana, primary, Yacoub, Amira, additional, Vallance, Jessica, additional, Compant, Stéphane, additional, Antonielli, Livio, additional, Saad, Ahmad, additional, Habenstein, Birgit, additional, Kauffmann, Brice, additional, Grélard, Axelle, additional, Loquet, Antoine, additional, Attard, Eléonore, additional, Guyoneaud, Rémy, additional, and Rey, Patrice, additional

Published
2021
Full Text
View/download PDF

35. Structures of Pathological and Functional Amyloids and Prions, a Solid-State NMR Perspective

Author

Daskalov, Asen, primary, El Mammeri, Nadia, additional, Lends, Alons, additional, Shenoy, Jayakrishna, additional, Lamon, Gaelle, additional, Fichou, Yann, additional, Saad, Ahmad, additional, Martinez, Denis, additional, Morvan, Estelle, additional, Berbon, Melanie, additional, Grélard, Axelle, additional, Kauffmann, Brice, additional, Ferber, Mathias, additional, Bardiaux, Benjamin, additional, Habenstein, Birgit, additional, Saupe, Sven J., additional, and Loquet, Antoine, additional

Published
2021
Full Text
View/download PDF

36. MRI assessment of multiple dipolar relaxation time ( T 1 D ) components in biological tissues interpreted with a generalized inhomogeneous magnetization transfer (ihMT) model

Author

Carvalho, Victor N.D., Hertanu, Andreea, Grélard, Axelle, Mchinda, Samira, Soustelle, Lucas, Loquet, Antoine, Dufourc, Erick J., Varma, Gopal, Alsop, David C., Thureau, Pierre, Girard, Olivier M., Duhamel, Guillaume, Centre de résonance magnétique biologique et médicale (CRMBM), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Beth Israel Deaconess - Harvard Medical School, ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011), ANR-17-CE18-0030,verISMO,IRM du transfert d'aimantation inhomogène : vers un nouveau biomarqueur in vivo spécifique et sensible de la myéline(2017), European Project: 713750,H2020,H2020-MSCA-COFUND-2015,DOC2AMU(2016), Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)

Subjects
T 1D, MRI contrast, Myelin, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Jeener-Broekaert, Dipolar relaxation time, Inhomogeneous magnetization transfer, Myelin Imaging, ihMT
Abstract

International audience; T 1D , the relaxation time of dipolar order, is sensitive to slow motional processes. Thus T 1D is a probe for membrane dynamics and organization that could be used to characterize myelin, the lipid-rich membrane of axonal fibers. A mono-component T 1D model associated with a modified ihMT sequence was previously proposed for in vivo evaluation of T 1D with MRI. However, experiments have suggested that myelinated tissues exhibit multiple T 1D components probably due to a heterogeneous molecular mobility. A bi-component T 1D model is proposed and implemented. ihMT images of ex-vivo, fixed rat spinal cord were acquired with multiple frequency alternation rate. Fits to data yielded two T 1D s of about 500 µs and 10 ms. The proposed model seems to further explore the complexity of myelin organization compared to the previously reported mono-component T 1D model.

Published
2020

37. Novel self-replicating α-synuclein polymorphs that escape ThT monitoring can spontaneously emerge and acutely spread in neurons

Author

De Giorgi, Francesca, Laferrière, Florent, Zinghirino, Federica, Faggiani, Emilie, Lends, Alons, Bertoni, Mathilde, Yu, Xuan, Grélard, Axelle, Morvan, Estelle, Habenstein, Birgit, Dutheil, Nathalie, Doudnikoff, Evelyne, Daniel, Jonathan, Claverol, Stéphane, Qin, Chuan, Loquet, Antoine, Bezard, Erwan, Ichas, François, Institut des Maladies Neurodégénératives [Bordeaux] (IMN), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de neurosciences expérimentales et cliniques (LNEC), Université de Poitiers-Institut National de la Santé et de la Recherche Médicale (INSERM), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Institut Européen de Chimie et Biologie (IECB), Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre Génomique Fonctionnelle Bordeaux [Bordeaux] (CGFB), Institut Polytechnique de Bordeaux-Université de Bordeaux Ségalen [Bordeaux 2], Université de Bordeaux (UB), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Laferriere, Florent

Subjects
Neurons, Amyloid, MESH: Multiple System Atrophy, Synucleinopathies, animal diseases, [SDV]Life Sciences [q-bio], [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, [SDV.NEU.NB] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology, SciAdv r-articles, Diseases and Disorders, macromolecular substances, nervous system diseases, Mice, nervous system, Cellular Neuroscience, mental disorders, MESH: alpha-Synuclein, alpha-Synuclein, Animals, Benzothiazoles, Research Articles, MESH: Parkinson Disease, Research Article
Abstract

Stealth α-synuclein amyloids proliferate in preparations of preformed fibrils and form aggressive self-replicating strains., The conformational strain diversity characterizing α-synuclein (α-syn) amyloid fibrils is thought to determine the different clinical presentations of neurodegenerative diseases underpinned by a synucleinopathy. Experimentally, various α-syn fibril polymorphs have been obtained from distinct fibrillization conditions by altering the medium constituents and were selected by amyloid monitoring using the probe thioflavin T (ThT). We report that, concurrent with classical ThT-positive products, fibrillization in saline also gives rise to polymorphs invisible to ThT (τ−). The generation of τ− fibril polymorphs is stochastic and can skew the apparent fibrillization kinetics revealed by ThT. Their emergence has thus been ignored so far or mistaken for fibrillization inhibitions/failures. They present a yet undescribed atomic organization and show an exacerbated propensity toward self-replication in cortical neurons, and in living mice, their injection into the substantia nigra pars compacta triggers a synucleinopathy that spreads toward the dorsal striatum, the nucleus accumbens, and the insular cortex.

Published
2020

38. Tandem NMR and Mass Spectrometry Analysis of Human Nuclear Membrane Lipids

Author

Eusko Jaurlaritza, Ministerio de Economía y Competitividad (España), Institut Européen de Chimie et Biologie (France), Centre National de la Recherche Scientifique (France), Institut National de la Santé et de la Recherche Médicale (France), Schmitter, Jean-Marie [0000-0001-7176-7813], Loquet, Antoine [0000-0003-4735-1169], Larijani, Banafshé [0000-0003-4735-1169], Dazzoni, Régine, Buré, Corinne, Morvan, Estelle, Grélard, Axelle, Gounou, Céline, Schmitter, Jean-Marie, Loquet, Antoine, Larijani, Banafshé, Dufourc, Erick J., Eusko Jaurlaritza, Ministerio de Economía y Competitividad (España), Institut Européen de Chimie et Biologie (France), Centre National de la Recherche Scientifique (France), Institut National de la Santé et de la Recherche Médicale (France), Schmitter, Jean-Marie [0000-0001-7176-7813], Loquet, Antoine [0000-0003-4735-1169], Larijani, Banafshé [0000-0003-4735-1169], Dazzoni, Régine, Buré, Corinne, Morvan, Estelle, Grélard, Axelle, Gounou, Céline, Schmitter, Jean-Marie, Loquet, Antoine, Larijani, Banafshé, and Dufourc, Erick J.

Abstract

The human nuclear membrane is composed of a double bilayer, the inner membrane being linked to the protein lamina network and the outer nuclear membrane continuous with the endoplasmic reticulum. Nuclear membranes can form large invaginations inside the nucleus; their specific roles still remain unknown. Although much of the protein identification has been determined, their lipid composition remains largely undetermined. In order to understand the mechanical and dynamic properties of nuclear membranes we investigated their lipid composition by two quantitative methods, namely, 31P and 1H multidimensional NMR and mass spectrometry, using internal standards. We also developed a nondetergent nuclei extraction protocol allowing to produce milligram quantities of nuclear membrane lipids. We found that the nuclear membrane lipid extract is composed of a complex mixture of phospholipids with different phosphatidylcholine species present in large amounts. Negatively charged lipids, with elevated amounts of phosphatidylinositol (PI), were also present. Mass spectrometry confirmed the phospholipid composition and provided further information on acyl-chain length and unsaturation. Lipid chain lengths ranged between 30 and 38 carbon atoms (two chains summed up) with a high proportion of 34 carbon atom length for most species. PI lipids have high amounts of chain lengths with 36-38 carbons. Independent of the chain length unsaturations were highly elevated with one to two double bonds per lipid species.

Published
2020

39. The unprecedented membrane deformation of the human nuclear envelope, in a magnetic field, indicates formation of nuclear membrane invaginations

Author

Université de Bordeaux, Universidad del País Vasco, Fundación Biofísica Bizkaia, Eusko Jaurlaritza, Ministerio de Economía y Competitividad (España), Centre National de la Recherche Scientifique (France), Dazzoni, Régine, Grélard, Axelle, Morvan, Estelle, Bouter, Anthony, Applebee, Christopher J., Loquet, Antoine, Larijani, Banafshé, Dufourc, Erick J., Université de Bordeaux, Universidad del País Vasco, Fundación Biofísica Bizkaia, Eusko Jaurlaritza, Ministerio de Economía y Competitividad (España), Centre National de la Recherche Scientifique (France), Dazzoni, Régine, Grélard, Axelle, Morvan, Estelle, Bouter, Anthony, Applebee, Christopher J., Loquet, Antoine, Larijani, Banafshé, and Dufourc, Erick J.

Abstract

Human nuclear membrane (hNM) invaginations are thought to be crucial in fusion, fission and remodeling of cells and present in many human diseases. There is however little knowledge, if any, about their lipid composition and dynamics. We therefore isolated nuclear envelope lipids from human kidney cells, analyzed their composition and determined the membrane dynamics after resuspension in buffer. The hNM lipid extract was composed of a complex mixture of phospholipids, with high amounts of phosphatidylcholines, phosphatidylinositols (PI) and cholesterol. hNM dynamics was determined by solid-state NMR and revealed that the lamellar gel-to-fluid phase transition occurs below 0 °C, reflecting the presence of elevated amounts of unsaturated fatty acid chains. Fluidity was higher than the plasma membrane, illustrating the dual action of Cholesterol (ordering) and PI lipids (disordering). The most striking result was the large magnetic field-induced membrane deformation allowing to determine the membrane bending elasticity, a property related to hydrodynamics of cells and organelles. Human Nuclear Lipid Membranes were at least two orders of magnitude more elastic than the classical plasma membrane suggesting a physical explanation for the formation of nuclear membrane invaginations.

Published
2020

40. Biophysical analysis of the plant-specific GIPC sphingolipids reveals multiple modes of membrane regulation

Author

Mamode Cassim, Adiilah, primary, Navon, Yotam, additional, Gao, Yu, additional, Decossas, Marion, additional, Fouillen, Laetitia, additional, Grélard, Axelle, additional, Nagano, Minoru, additional, Lambert, Olivier, additional, Bahammou, Delphine, additional, Van Delft, Pierre, additional, Maneta-Peyret, Lilly, additional, Simon-Plas, Françoise, additional, Heux, Laurent, additional, Jean, Bruno, additional, Fragneto, Giovanna, additional, Mortimer, Jenny C., additional, Deleu, Magali, additional, Lins, Laurence, additional, and Mongrand, Sébastien, additional

Published
2021
Full Text
View/download PDF

43. Purification, characterization and influence on membrane properties of the plant-specific sphingolipids GIPC

Author

Cassim, Adiilah Mamode, primary, Navon, Yotam, additional, Gao, Yu, additional, Decossas, Marion, additional, Fouillen, Laetitia, additional, Grélard, Axelle, additional, Nagano, Minoru, additional, Lambert, Olivier, additional, Bahammou, Delphine, additional, Van Delft, Pierre, additional, Maneta-Peyret, Lilly, additional, Simon-Plas, Françoise, additional, Heux, Laurent, additional, Fragneto, Giovanna, additional, Mortimer, Jenny C., additional, Deleu, Magali, additional, Lins, Laurence, additional, and Mongrand, Sébastien, additional

Published
2020
Full Text
View/download PDF

46. Emergence of stealth polymorphs that escape α-synuclein amyloid monitoring, take over and acutely spread in neurons

Author

De Giorgi, Francesca, primary, Laferrière, Florent, additional, Zinghirino, Federica, additional, Faggiani, Emilie, additional, Lends, Alons, additional, Bertoni, Mathilde, additional, Yu, Xuan, additional, Grélard, Axelle, additional, Morvan, Estelle, additional, Habenstein, Birgit, additional, Dutheil, Nathalie, additional, Doudnikoff, Evelyne, additional, Daniel, Jonathan, additional, Claverol, Stéphane, additional, Qin, Chuan, additional, Loquet, Antoine, additional, Bezard, Erwan, additional, and Ichas, François, additional

Published
2020
Full Text
View/download PDF

47. MRI assessment of multiple dipolar relaxation time (T1D) components in biological tissues interpreted with a generalized inhomogeneous magnetization transfer (ihMT) model

Author

Carvalho, Victor N.D., primary, Hertanu, Andreea, additional, Grélard, Axelle, additional, Mchinda, Samira, additional, Soustelle, Lucas, additional, Loquet, Antoine, additional, Dufourc, Erick J., additional, Varma, Gopal, additional, Alsop, David C., additional, Thureau, Pierre, additional, Girard, Olivier M., additional, and Duhamel, Guillaume, additional

Published
2020
Full Text
View/download PDF

48. Structural dissection of amyloid aggregates of TDP‐43 and its C‐terminal fragments TDP‐35 and TDP‐16

Author

Shenoy, Jayakrishna, primary, El Mammeri, Nadia, additional, Dutour, Antoine, additional, Berbon, Mélanie, additional, Saad, Ahmad, additional, Lends, Alons, additional, Morvan, Estelle, additional, Grélard, Axelle, additional, Lecomte, Sophie, additional, Kauffmann, Brice, additional, Theillet, François‐Xavier, additional, Habenstein, Birgit, additional, and Loquet, Antoine, additional

Published
2019
Full Text
View/download PDF

49. itms

Author

Jobin, Marie-Lise, Vamparys, Lydie, Deniau, Romain, Grélard, Axelle, Mackereth, Cameron, Fuchs, Patrick, Alves, Isabel, Chimie et Biologie des Membranes et des Nanoobjets (CBMN), École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Institut Jacques Monod (IJM (UMR_7592)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Acides Nucléiques : Régulations Naturelle et Artificielle (ARNA), Université de Bordeaux (UB)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Bioinformatique génomique et moléculaire ((U 726)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Diderot - Paris 7 (UPD7), Université Sciences et Technologies - Bordeaux 1-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Centre National de la Recherche Scientifique (CNRS), Régulations Naturelles et Artificielles (ARNA), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Bordeaux Ségalen [Bordeaux 2], Laboratoire des biomolécules (LBM UMR 7203), Institut National de la Santé et de la Recherche Médicale (INSERM)-Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), and Alves, Isabel

Subjects
[CHIM.MATE] Chemical Sciences/Material chemistry, peptide–lipid interaction, [SDV.BBM.BP] Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, [CHIM.MATE]Chemical Sciences/Material chemistry, molecular dynamics, NMR, [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, lcsh:Chemistry, lipid model systems, lcsh:Biology (General), lcsh:QD1-999, peptide-lipid interaction, membrane biophysics, lcsh:QH301-705.5, cell-penetrating peptide
Abstract

International audience; Cell-penetrating peptides (CPPs) are short peptides that can translocate and transport cargoes into the intracellular milieu by crossing biological membranes. The mode of interaction and internalization of cell-penetrating peptides has long been controversial. While their interaction with anionic membranes is quite well understood, the insertion and behavior of CPPs in zwitterionic membranes, a major lipid component of eukaryotic cell membranes, is poorly studied. Herein, we investigated the membrane insertion of RW16 into zwitterionic membranes, a versatile CPP that also presents antibacterial and antitumor activities. Using complementary approaches, including NMR spectroscopy, fluorescence spectroscopy, circular dichroism, and molecular dynamic simulations, we determined the high-resolution structure of RW16 and measured its membrane insertion and orientation properties into zwitterionic membranes. Altogether, these results contribute to explaining the versatile properties of this peptide toward zwitterionic lipids.

Published
2019

50. Multicomponent dipolar relaxation time (T1D) assessment in myelin using inhmogeneous magnetization transfer (ihMT) MRI

Author

Carvalho, Victor, Girard, Olivier M., Hertanu, Andreea, Soustelle, Lucas, Grélard, Axelle, Loquet, Antoine, Dufourc, Erick J., Varma, Gopal, Alsop, David C., Thureau, Pierre, Duhamel, Guillaume, Centre de résonance magnétique biologique et médicale (CRMBM), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Chimie et Biologie des Membranes et des Nanoobjets (CBMN), Université de Bordeaux (UB)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Beth Israel Deaconess - Harvard Medical School, Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Duhamel, Guillaume, Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB)-Institut de Chimie du CNRS (INC)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.IB.IMA] Life Sciences [q-bio]/Bioengineering/Imaging, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, [INFO.INFO-IM] Computer Science [cs]/Medical Imaging, [INFO.INFO-IM]Computer Science [cs]/Medical Imaging, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

Catalog

Books, media, physical & digital resources
See catalog results