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Accueil > Publications

Publications plate-forme I2BC

2017


  • L. Becker, S. Bellow, V. Carré, G. Latouche, A. Poutaraud, D. Merdinoglu, S. C. Brown, Z. G. Cerovic, et P. Chaimbault, « Correlative Analysis of Fluorescent Phytoalexins by Mass Spectrometry Imaging and Fluorescence Microscopy in Grapevine Leaves », Analytical Chemistry, 2017.
    Résumé : Plant response to their environment stresses is a complex mechanism involving secondary metabolites. Stilbene phytoalexins, namely resveratrol, pterostilbene, piceids and viniferins play a key role in grapevine (Vitis vinifera) leaf defense. Despite their well-established qualities, conventional analyses such as HPLC-DAD or LC-MS lose valuable information on metabolite localization during the extraction process. To overcome this issue, a correlative analysis combining mass spectroscopy imaging (MSI) and fluorescence imaging was developed to localize in situ stilbenes on the same stressed grapevine leaves. High-resolution images of the stilbene fluorescence provided by macroscopy were supplemented by specific distributions and structural information concerning resveratrol, pterostilbene, and piceids obtained by MSI. The two imaging techniques led to consistent and complementary data on the stilbene spatial distribution for the two stresses addressed: UV-C irradiation and infection by Plasmopara viticola. Results emphasize that grapevine leaves react differently depending on the stress. A rather uniform synthesis of stilbenes is induced after UV-C irradiation, whereas a more localized synthesis of stilbenes in stomata guard cells and cell walls is induced by P. viticola infection. Finally, this combined imaging approach could be extended to map phytoalexins of various plant tissues with resolution approaching the cellular level.
    Mots-clés : IMAGIF, PF, PHOT.

  • C. Bou-Nader, D. Cornu, V. Guerineau, T. Fogeron, M. Fontecave, et D. Hamdane, « Enzyme Activation with a Synthetic Catalytic Co-enzyme Intermediate: Nucleotide Methylation by Flavoenzymes », Angewandte Chemie (International Ed. in English), 2017.
    Résumé : To facilitate production of functional enzymes and to study their mechanisms, especially in the complex cases of coenzyme-dependent systems, activation of an inactive apoenzyme preparation with a catalytically competent coenzyme intermediate is an attractive strategy. This is illustrated with the simple chemical synthesis of a flavin-methylene iminium compound previously proposed as a key intermediate in the catalytic cycle of several important flavoenzymes involved in nucleic acid metabolism. Reconstitution of both flavin-dependent RNA methyltransferase and thymidylate synthase apoproteins with this synthetic compound led to active enzymes for the C5-uracil methylation within their respective transfer RNA and dUMP substrate. This strategy is expected to be of general application in enzymology.
    Mots-clés : artificial enzymes, flavoenzyme mechanism, Methylation, Nucleotides, PF, reaction intermediates, SICAPS.

  • S. C. Brown, M. Bourge, N. Maunoury, M. Wong, M. W. Bianchi, S. Lepers-Andrzejewski, P. Besse, S. Siljak-Yakovlev, M. Dron, et B. Satiat-Jeunemaître, « DNA remodelling by Strict Partial Endoreplication in orchids, an original process in the plant kingdom », Genome Biology and Evolution, 2017.
    Résumé : DNA remodelling during endoreplication appears to be a strong developmental characteristic in orchids. In this study, we analysed DNA content and nuclei in 41 species of orchids to further map the genome evolution in this plant family. We demonstrate that the DNA remodelling observed in 36 out of 41 orchids studied corresponds to strict partial endoreplication. Such process is developmentally regulated in each wild species studied. Cytometry data analyses allowed us to propose a model where nuclear states 2C, 4E, 8E, etc. form a series comprising a fixed proportion, the euploid genome 2C, plus 2 to 32 additional copies of a complementary part of the genome. The fixed proportion ranged from 89% of the genome in Vanilla mexicana down to 19% in V. pompona, the lowest value for all 148 orchids reported. Insterspecific hybridisation did not suppress this phenomenon. Interestingly, this process was not observed in mass-produced epiphytes. Nucleolar volumes grow with the number of endocopies present, coherent with high transcription activity in endoreplicated nuclei. Our analyses suggest species-specific chromatin rearrangement. Towards understanding endoreplication, V. planifolia constitutes a tractable system for isolating the genomic sequences that confer an advantage via endoreplication from those that apparently suffice at diploid level.
    Mots-clés : BIOCELL, CYTO, cytogenetics, cytometry, DYNBSJ, endoreplication, genome imbalance, Genome Size, IMAGIF, PF, PHOT, Vanilla.


  • E. Dambroise, M. Simion, T. Bourquard, S. Bouffard, B. Rizzi, Y. Jaszczyszyn, M. Bourge, P. Affaticati, A. Heuzé, J. Jouralet, J. Edouard, S. Brown, C. Thermes, A. Poupon, E. Reiter, F. Sohm, F. Bourrat, et J. - S. Joly, « Postembryonic Fish Brain Proliferation Zones Exhibit Neuroepithelial-Type Gene Expression Profile: Features of Neuroepithelial Cells in Fish », STEM CELLS, 2017.
    Mots-clés : BMgif, CYTO, IMAGIF, NGS, PF, PHOT.

  • T. Di Meo, W. Ghattas, C. Herrero, C. Velours, P. Minard, J. - P. Mahy, R. Ricoux, et A. Urvoas, « αRep A3: A versatile artificial scaffold for metalloenzyme design », Chemistry (Weinheim an Der Bergstrasse, Germany), 2017.
    Résumé : αRep is a new family of artificial proteins based on a thermostable alpha-helical repeated motif. One of its members, αRep A3, forms a stable homo-dimer with a wide cleft that is able to receive metal complexes and thus appears as suitable for generating new artificial biocatalysts. Based on the crystal structure of αRep A3, two positions (F119 and Y26) were chosen and changed independently into cysteine residues. A phenanthroline ligand was covalently attached to the unique cysteine of each protein variant and the corresponding biohybrids were purified and characterized. Once mutated and coupled to phenanthroline, the protein remained folded and dimeric. Copper(II) was bound specifically by the two biohybrids with two different binding modes and, in addition, the holo biohybrid A3F119NPH was found to be able to catalyze enantioselectively the Diels-Alder (D-A) cycloaddition with up to 62% ee. This study validates the choice of the αRep A3 dimer as a protein scaffold and provides a new promising route for the design and production of new enantioselective biohybrids based on entirely artificial proteins issued from a highly diverse library.
    Mots-clés : artificial repeat proteins, B3S, Diels-Alder reaction, Enantioselective Catalysis, MIP, PF, PIM.


  • R. El Helou, G. Pinna, O. Cabaud, J. Wicinski, R. Bhajun, L. Guyon, C. Rioualen, P. Finetti, A. Gros, B. Mari, P. Barbry, F. Bertucci, G. Bidaut, A. Harel-Bellan, D. Birnbaum, E. Charafe-Jauffret, et C. Ginestier, « miR-600 Acts as a Bimodal Switch that Regulates Breast Cancer Stem Cell Fate through WNT Signaling », Cell Reports, vol. 18, nᵒ 9, p. 2256-2268, 2017.

  • C. Esnault, D. Leiber, C. Toffano-Nioche, Z. Tanfin, et M. - J. Virolle, « Another example of enzymatic promiscuity: the polyphosphate kinase of Streptomyces lividans is endowed with phospholipase D activity », Applied Microbiology and Biotechnology, vol. 101, nᵒ 1, p. 139-145, 2017.
    Résumé : Polyphosphate kinases (PPK) from different bacteria, including that of Streptomyces lividans, were shown to contain the typical HKD motif present in phospholipase D (PLD) and showed structural similarities to the latter. This observation prompted us to investigate the PLD activity of PPK of S. lividans, in vitro. The ability of PPK to catalyze the hydrolysis of phosphatidylcholine (PC), the PLD substrate, was assessed by the quantification of [(3)H]phosphatidic acid (PA) released from [(3)H]PC-labeled ELT3 cell membranes. Basal cell membrane PLD activity as well as GTPγS-activated PLD activity was higher in the presence than in absence of PPK. After abolition of the basal PLD activity of the membranes by heat or tryptic treatment, the addition of PPK to cell membranes was still accompanied by an increased production of PA demonstrating that PPK also bears a PLD activity. PLD activity of PPK was also assessed by the production of choline from hydrolysis of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) in the presence of the Amplex Red reagent and compared to two commercial PLD enzymes. These data demonstrated that PPK is endowed with a weak but clearly detectable PLD activity. The question of the biological signification, if any, of this enzymatic promiscuity is discussed.
    Mots-clés : Amino Acid Motifs, Cell Membrane, Choline, eBio, Hydrolysis, Lipid droplets, MESMIC, MICROBIO, PF, Phosphatidic Acids, Phosphatidylcholines, Phospholipase D, Phosphotransferases (Phosphate Group Acceptor), Polyphosphate kinase, Promiscuous enzyme, Protein Conformation, Streptomyces lividans.


  • J. Lang, A. Vigouroux, A. El Sahili, A. Kwasiborski, M. Aumont-Nicaise, Y. Dessaux, J. A. Shykoff, S. Moréra, et D. Faure, « Fitness costs restrict niche expansion by generalist niche-constructing pathogens », The ISME Journal, vol. 11, nᵒ 2, p. 374-385, 2017.
    Mots-clés : B3S, MESB3S, MICROBIO, PBI, PF, PIM.

  • L. Loiseau, C. Fyfe, L. Aussel, M. Hajj Chehade, S. B. Hernández, B. Faivre, D. Hamdane, C. Mellot-Draznieks, B. Rascalou, L. Pelosi, C. Velours, D. Cornu, M. Lombard, J. Casadesús, F. Pierrel, M. Fontecave, et F. Barras, « The UbiK protein is an accessory factor necessary for bacterial ubiquinone (UQ) biosynthesis and forms a complex with the UQ biogenesis factor UbiJ », The Journal of Biological Chemistry, 2017.
    Résumé : Ubiquinone (UQ), also referred to as coenzyme Q, is a widespread lipophilic molecule in both prokaryotes and eukaryotes in which it primarily acts as an electron carrier. Eleven proteins are known to participate in UQ biosynthesis in Escherichia coli, and we recently demonstrated that UQ biosynthesis requires additional, nonenzymatic factors, some of which are still unknown. Here, we report on the identification of a bacterial gene, yqiC, which is required for efficient UQ biosynthesis, and which we have renamed ubiK. Using several methods, we demonstrated that the UbiK protein forms a complex with the C-terminal part of UbiJ, another UQ biogenesis factor we previously identified. We found that both proteins are likely to contribute to global UQ biosynthesis rather than to a specific biosynthetic step, since both ubiK and ubiJ mutants accumulated octaprenylphenol, an early intermediate of the UQ biosynthetic pathway. Interestingly, we found that both proteins are dispensable for UQ biosynthesis under anaerobiosis, even though they were expressed in the absence of oxygen. We also provide evidence that the UbiK-UbiJ complex interacts with palmitoleic acid, a major lipid in E. coli. Last, in Salmonella enterica, ubiK was required for proliferation in macrophages and virulence in mice. We conclude that although the role of the UbiK-UbiJ complex remains unknown, our results support the hypothesis that UbiK is an accessory factor of Ubi enzymes and facilitates UQ biosynthesis by acting as an assembly factor, a targeting factor, or both.
    Mots-clés : bioenergetics, coenzyme Q10 (CoQ10), Electron transfer, Escherichia coli (E. coli), Microbiology, PF, PIM, SICAPS, Ubiquinone.

  • M. Ma, I. Li de La Sierra Gallay, N. Lazar, O. Pellegrini, J. Lepault, C. Condon, D. Durand, et H. van Tilbeurgh, « Trz1, the long form RNase Z from yeast, forms a stable heterohexamer with endonuclease Nuc1 and mutarotase », The Biochemical Journal, 2017.
    Résumé : Proteomic studies haves established that Trz1, Nuc1 and mutarotase form a complex in yeast. Trz1 is a b-lactamase type RNase composed of two b-lactamase type domains connected by a long linker that is responsible for the endonucleolytic cleavage at the 3'-end of tRNAs during the maturation process (RNase Z activity); Nuc1 is a dimeric mitochondrial nuclease involved in apoptosis, while mutarotase (encoded by YMR099C) catalyzes the conversion between the a- and b-configuration of glucose-6-phosphate. Using gel-filtration, SAXS and electron microscopy we demonstrated that Trz1, Nuc1 and mutarotase form a very stable heterohexamer, composed of two copies of each of the three subunits. A Nuc1 homodimer is at the centre of the complex, creating a two-fold symmetry and interacting with both Trz1 and mutarotase. Enzymatic characterization of the ternary complex revealed that the activities of Trz1 and mutarotase are not affected by complex formation, but that the Nuc1 activity is completely inhibited by mutarotase and partially by Trz1. This suggests that mutarotase and Trz1 might be regulators of the Nuc1 apoptotic nuclease activity.
    Mots-clés : B3S, complex, CRYOEM, endoglucanase, FAAM, mutarotase, PF, RNASeZ, structure.


  • J. Marion, R. Le Bars, B. Satiat-Jeunemaitre, et C. Boulogne, « Optimizing CLEM protocols for plants cells: GMA embedding and cryosections as alternatives for preservation of GFP fluorescence in Arabidopsis roots », Journal of Structural Biology, 2017.
    Mots-clés : Arabidopsis, BIOCELL, Correlative microscopy, DYNBSJ, GFP, GMA resin, IMAGIF, MET, PF, PHOT, Tokuyasu, Transmission electron microscopy.

  • S. Nagarajan, H. Belaid, C. Pochat-Bohatier, C. Teyssier, I. Iatsunskyi, E. Coy, S. Balme, D. Cornu, P. Miele, N. S. Kalkura, V. Cavailles, et M. Bechelany, « Design of Boron Nitride/Gelatin Electrospun Nanofibers for Bone Tissue Engineering », ACS applied materials & interfaces, 2017.
    Résumé : Gelatin is a biodegradable biopolymer obtained by collagen denaturation, which shows poor mechanical properties. Hence, improving its mechanical properties is very essential towards the fabrication of efficient nontoxic material for biomedical applications. For this aim, various methods are employed using external fillers such as ceramics or bioglass. In this report, we introduce boron nitride (BN) reinforced gelatin as a new class of two dimensional biocompatible nanomaterials. The effect of the nanofiller on the mechanical behavior is analyzed. BN is efficiently exfoliated using the biopolymer gelatin as shown through Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The exfoliated BN reinforces gelatin electrospun fibers, which results in an increase in the Young's modulus. The ESM are stable after the glutaraldehyde cross-linking and the fibrous morphology is preserved. The cross-linked gelatin/BN ESM is highly bioactive in forming bone like hydroxyapatite as shown by scanning electron microscopy. Due to their enhanced mineralization ability, the cross-linked ESM have been tested on human bone cells (HOS osteosarcoma cell line). The cell attachment, proliferation and biocompatibility results show that the ESM are nontoxic and biodegradable. The analysis of osteoblast gene expression and the measurement of alkaline phosphatase activity confirm that these materials are suitable for bone tissue engineering.
    Mots-clés : PF, SICAPS.

  • J. Nikolic, R. Le Bars, Z. Lama, N. Scrima, C. Lagaudrière-Gesbert, Y. Gaudin, et D. Blondel, « Negri bodies are viral factories with properties of liquid organelles », Nature Communications, vol. 8, nᵒ 1, p. 58, 2017.
    Résumé : Replication of Mononegavirales occurs in viral factories which form inclusions in the host-cell cytoplasm. For rabies virus, those inclusions are called Negri bodies (NBs). We report that NBs have characteristics similar to those of liquid organelles: they are spherical, they fuse to form larger structures, and they disappear upon hypotonic shock. Their liquid phase is confirmed by FRAP experiments. Live-cell imaging indicates that viral nucleocapsids are ejected from NBs and transported along microtubules to form either new virions or secondary viral factories. Coexpression of rabies virus N and P proteins results in cytoplasmic inclusions recapitulating NBs properties. This minimal system reveals that an intrinsically disordered domain and the dimerization domain of P are essential for Negri bodies-like structures formation. We suggest that formation of liquid viral factories by phase separation is common among Mononegavirales and allows specific recruitment and concentration of viral proteins but also the escape to cellular antiviral response.Negative strand RNA viruses, such as rabies virus, induce formation of cytoplasmic inclusions for genome replication. Here, Nikolic et al. show that these so-called Negri bodies (NBs) have characteristics of liquid organelles and they identify the minimal protein domains required for NB formation.
    Mots-clés : IMAGIF, PF, PHOT, RHABDO, VIRO.


  • J. - A. Pedroza-García, C. Mazubert, I. del Olmo, M. Bourge, S. Domenichini, R. Bounon, Z. Tariq, E. Delannoy, M. Piñeiro, J. A. Jarillo, C. Bergounioux, M. Benhamed, et C. Raynaud, « Function of the Plant DNA Polymerase Epsilon in Replicative Stress Sensing, a Genetic Analysis », Plant Physiology, vol. 173, nᵒ 3, p. 1735-1749, 2017.


  • P. Pétriacq, L. de Bont, L. Genestout, J. Hao, C. Laureau, I. Florez-Sarasa, T. Rzigui, G. Queval, F. Gilard, C. Mauve, F. Guérard, M. Lamothe-Sibold, J. Marion, C. Fresneau, S. Brown, A. Danon, A. Krieger-Liszkay, R. Berthomé, M. Ribas-Carbo, G. Tcherkez, G. Cornic, B. Pineau, B. Gakière, et R. De Paepe, « Photoperiod Affects the Phenotype of Mitochondrial Complex I Mutants », Plant Physiology, vol. 173, nᵒ 1, p. 434-455, 2017.
    Mots-clés : B3S, BIOCELL, DYNBSJ, IMAGIF, MROP, PF, PHOT.

  • S. Robinson, J. Nevalainen, G. Pinna, A. Campalans, J. P. Radicella, et L. Guyon, « Incorporating interaction networks into the determination of functionally related hit genes in genomic experiments with Markov random fields », Bioinformatics (Oxford, England), vol. 33, nᵒ 14, p. i170-i179, 2017.
    Résumé : Motivation: Incorporating gene interaction data into the identification of 'hit' genes in genomic experiments is a well-established approach leveraging the 'guilt by association' assumption to obtain a network based hit list of functionally related genes. We aim to develop a method to allow for multivariate gene scores and multiple hit labels in order to extend the analysis of genomic screening data within such an approach. Results: We propose a Markov random field-based method to achieve our aim and show that the particular advantages of our method compared with those currently used lead to new insights in previously analysed data as well as for our own motivating data. Our method additionally achieves the best performance in an independent simulation experiment. The real data applications we consider comprise of a survival analysis and differential expression experiment and a cell-based RNA interference functional screen. Availability and implementation: We provide all of the data and code related to the results in the paper. Contact: sean.j.robinson@utu.fi or laurent.guyon@cea.fr. Supplementary information: Supplementary data are available at Bioinformatics online.
    Mots-clés : PARI, PF.


  • C. Samson, F. Celli, K. Hendriks, M. Zinke, N. Essawy, I. Herrada, A. - A. Arteni, F. - X. Theillet, B. Alpha-Bazin, J. Armengaud, C. Coirault, A. Lange, et S. Zinn-Justin, « Emerin self-assembly mechanism: role of the LEM domain », The FEBS Journal, vol. 284, nᵒ 2, p. 338-352, 2017.
    Mots-clés : B3S, CRYOEM, INTGEN, PF.


  • P. V. Sauer, J. Timm, D. Liu, D. Sitbon, E. Boeri-Erba, C. Velours, N. Mücke, J. Langowski, F. Ochsenbein, G. Almouzni, et D. Panne, « Insights into the molecular architecture and histone H3-H4 deposition mechanism of yeast Chromatin assembly factor 1 », eLife, vol. 6, mars 2017.
    Mots-clés : AMIG, B3S, PF, PIM.


  • Z. M. Song, L. Bouchab, E. Hudik, R. Le Bars, O. Nüsse, et S. Dupré-Crochet, « Phosphoinositol 3-phosphate acts as a timer for reactive oxygen species production in the phagosome », Journal of Leukocyte Biology, p. jlb.1A0716-305R, janv. 2017.


  • A. Talagas, L. Fontaine, L. Ledesma-García, J. Mignolet, I. Li de la Sierra-Gallay, N. Lazar, M. Aumont-Nicaise, M. J. Federle, G. Prehna, P. Hols, et S. Nessler, « Correction: Structural Insights into Streptococcal Competence Regulation by the Cell-to-Cell Communication System ComRS », PLOS Pathogens, vol. 13, nᵒ 2, p. e1006208, févr. 2017.
    Mots-clés : B3S, FAAM, PF, PIM.

2016



  • S. Ahmad, L. Pecqueur, B. Dreier, D. Hamdane, M. Aumont-Nicaise, A. Plückthun, M. Knossow, et B. Gigant, « Destabilizing an interacting motif strengthens the association of a designed ankyrin repeat protein with tubulin », Scientific Reports, vol. 6, p. 28922, juill. 2016.
    Mots-clés : B3S, MIKICA, PF, PIM.

  • C. Aillaud, C. Bosc, Y. Saoudi, E. Denarier, L. Peris, L. Sago, N. Taulet, A. Cieren, O. Tort, M. M. Magiera, C. Janke, V. Redeker, A. Andrieux, et M. - J. Moutin, « Evidence for new C-terminally truncated variants of α- and β-tubulins », Molecular Biology of the Cell, vol. 27, nᵒ 4, p. 640-653, 2016.
    Résumé : Cellular α-tubulin can bear various carboxy-terminal sequences: full-length tubulin arising from gene neosynthesis is tyrosinated, and two truncated variants, corresponding to detyrosinated and Δ2 α‑tubulin, result from the sequential cleavage of one or two C-terminal residues, respectively. Here, by using a novel antibody named 3EG that is highly specific to the -EEEG C-terminal sequence, we demonstrate the occurrence in neuronal tissues of a new αΔ3‑tubulin variant corresponding to α1A/B‑tubulin deleted of its last three residues (EEY). αΔ3‑tubulin has a specific distribution pattern: its quantity in the brain is similar to that of αΔ2-tubulin around birth but is much lower in adult tissue. This truncated α1A/B-tubulin variant can be generated from αΔ2-tubulin by the deglutamylases CCP1, CCP4, CCP5, and CCP6 but not by CCP2 and CCP3. Moreover, using 3EG antibody, we identify a C‑terminally truncated β-tubulin form with the same -EEEG C-terminal sequence. Using mass spectrometry, we demonstrate that β2A/B-tubulin is modified by truncation of the four C-terminal residues (EDEA). We show that this newly identified βΔ4-tubulin is ubiquitously present in cells and tissues and that its level is constant throughout the cell cycle. These new C-terminally truncated α- and β-tubulin variants, both ending with -EEEG sequence, are expected to regulate microtubule physiology. Of interest, the αΔ3-tubulin seems to be related to dynamic microtubules, resembling tyrosinated-tubulin rather than the other truncated variants, and may have critical function(s) in neuronal development.
    Mots-clés : Amino Acid Sequence, Animals, Brain, Carboxypeptidases, cell cycle, Gene Knockdown Techniques, HEK293 Cells, HeLa Cells, Humans, Mass Spectrometry, Mice, Microtubules, Molecular Sequence Data, Neurogenesis, Neurons, Peptide Synthases, PF, Protein Processing, Post-Translational, SICAPS, Tubulin, Tyrosine.


  • M. Benincasa, Q. Barrière, G. Runti, O. Pierre, M. Bourge, M. Scocchi, et P. Mergaert, « Single Cell Flow Cytometry Assay for Peptide Uptake by Bacteria », BIO-PROTOCOL, vol. 6, nᵒ 23, 2016.
    Mots-clés : CYTO, IMAGIF, MICROBIO, PBI, PF.

  • C. Chaintreuil, D. Gully, C. Hervouet, P. Tittabutr, H. Randriambanona, S. C. Brown, G. P. Lewis, M. Bourge, F. Cartieaux, M. Boursot, H. Ramanankierana, A. D'Hont, N. Teaumroong, E. Giraud, et J. - F. Arrighi, « The evolutionary dynamics of ancient and recent polyploidy in the African semiaquatic species of the legume genus Aeschynomene », The New Phytologist, vol. 211, nᵒ 3, p. 1077-1091, 2016.
    Résumé : The legume genus Aeschynomene is notable in the ability of certain semiaquatic species to develop nitrogen-fixing stem nodules. These species are distributed in two clades. In the first clade, all the species are characterized by the use of a unique Nod-independent symbiotic process. In the second clade, the species use a Nod-dependent symbiotic process and some of them display a profuse stem nodulation as exemplified in the African Aeschynomene afraspera. To facilitate the molecular analysis of the symbiotic characteristics of such legumes, we took an integrated molecular and cytogenetic approach to track occurrences of polyploidy events and to analyze their impact on the evolution of the African species of Aeschynomene. Our results revealed two rounds of polyploidy: a paleopolyploid event predating the African group and two neopolyploid speciations, along with significant chromosomal variations. Hence, we found that A. afraspera (8x) has inherited the contrasted genomic properties and the stem-nodulation habit of its parental lineages (4x). This study reveals a comprehensive picture of African Aeschynomene diversification. It notably evidences a history that is distinct from the diploid Nod-independent clade, providing clues for the identification of the specific determinants of the Nod-dependent and Nod-independent symbiotic processes, and for comparative analysis of stem nodulation.
    Mots-clés : Aeschynomene, CYTO, dysploidy, genome downsizing, IMAGIF, PF, PHOT, Polyploidy, stem nodulation, Symbiosis.

  • A. de Saint Germain, G. Clavé, M. - A. Badet-Denisot, J. - P. Pillot, D. Cornu, J. - P. Le Caer, M. Burger, F. Pelissier, P. Retailleau, C. Turnbull, S. Bonhomme, J. Chory, C. Rameau, et F. - D. Boyer, « An histidine covalent receptor and butenolide complex mediates strigolactone perception », Nature Chemical Biology, vol. 12, nᵒ 10, p. 787-794, 2016.
    Résumé : Strigolactone plant hormones control plant architecture and are key players in both symbiotic and parasitic interactions. They contain an ABC tricyclic lactone connected to a butenolide group, the D ring. The DWARF14 (D14) strigolactone receptor belongs to the superfamily of α/β-hydrolases, and is known to hydrolyze the bond between the ABC lactone and the D ring. Here we characterized the binding and catalytic functions of RAMOSUS3 (RMS3), the pea (Pisum sativum) ortholog of rice (Oryza sativa) D14 strigolactone receptor. Using new profluorescent probes with strigolactone-like bioactivity, we found that RMS3 acts as a single-turnover enzyme that explains its apparent low enzymatic rate. We demonstrated the formation of a covalent RMS3-D-ring complex, essential for bioactivity, in which the D ring was attached to histidine 247 of the catalytic triad. These results reveal an undescribed mechanism of plant hormone reception in which the receptor performs an irreversible enzymatic reaction to generate its own ligand.
    Mots-clés : PF, SICAPS.


  • E. Deforzh, T. Vargas, J. Kropp, M. Vandamme, G. Pinna, et A. Polesskaya, « IMP-3 protects the mRNAs of cyclins D1 and D3 from GW182/AGO2-dependent translational repression », International Journal of Oncology, oct. 2016.
    Mots-clés : DBG, PARI, PF, RPTEG.

  • T. Eychenne, E. Novikova, M. - B. Barrault, O. Alibert, C. Boschiero, N. Peixeiro, D. Cornu, V. Redeker, L. Kuras, P. Nicolas, M. Werner, et J. Soutourina, « Functional interplay between Mediator and TFIIB in preinitiation complex assembly in relation to promoter architecture », Genes & Development, vol. 30, nᵒ 18, p. 2119-2132, 2016.
    Résumé : Mediator is a large coregulator complex conserved from yeast to humans and involved in many human diseases, including cancers. Together with general transcription factors, it stimulates preinitiation complex (PIC) formation and activates RNA polymerase II (Pol II) transcription. In this study, we analyzed how Mediator acts in PIC assembly using in vivo, in vitro, and in silico approaches. We revealed an essential function of the Mediator middle module exerted through its Med10 subunit, implicating a key interaction between Mediator and TFIIB. We showed that this Mediator-TFIIB link has a global role on PIC assembly genome-wide. Moreover, the amplitude of Mediator's effect on PIC formation is gene-dependent and is related to the promoter architecture in terms of TATA elements, nucleosome occupancy, and dynamics. This study thus provides mechanistic insights into the coordinated function of Mediator and TFIIB in PIC assembly in different chromatin contexts.
    Mots-clés : DBG, GTR, Mediator, PEPS, PF, preinitiation complex, promoter architecture, RNA polymerase II transcription, Saccharomyces cerevisiae, SICAPS, TFIIB.


  • E. Galli, M. Poidevin, R. Le Bars, J. - M. Desfontaines, L. Muresan, E. Paly, Y. Yamaichi, et F. - X. Barre, « Cell division licensing in the multi-chromosomal Vibrio cholerae bacterium », Nature Microbiology, vol. 1, nᵒ 9, p. 16094, juin 2016.
    Mots-clés : DBG, EMC2, EQYY, IMAGIF, PF, PHOT.

  • J. Hai, N. Serradji, L. Mouton, V. Redeker, D. Cornu, J. - M. El Hage Chahine, P. Verbeke, et M. Hémadi, « Targeted Delivery of Amoxicillin to C. trachomatis by the Transferrin Iron Acquisition Pathway », PloS One, vol. 11, nᵒ 2, p. e0150031, 2016.
    Résumé : Weak intracellular penetration of antibiotics makes some infections difficult to treat. The Trojan horse strategy for targeted drug delivery is among the interesting routes being explored to overcome this therapeutic difficulty. Chlamydia trachomatis, as an obligate intracellular human pathogen, is responsible for both trachoma and sexually transmitted diseases. Chlamydia develops in a vacuole and is therefore protected by four membranes (plasma membrane, bacterial inclusion membrane, and bacterial membranes). In this work, the iron-transport protein, human serum-transferrin, was used as a Trojan horse for antibiotic delivery into the bacterial vacuole. Amoxicillin was grafted onto transferrin. The transferrin-amoxicillin construct was characterized by mass spectrometry and absorption spectroscopy. Its affinity for transferrin receptor 1, determined by fluorescence emission titration [KaffTf-amox = (1.3 ± 1.0) x 108], is very close to that of transferrin [4.3 x 108]. Transmission electron and confocal microscopies showed a co-localization of transferrin with the bacteria in the vacuole and were also used to evaluate the antibiotic capability of the construct. It is significantly more effective than amoxicillin alone. These promising results demonstrate targeted delivery of amoxicillin to suppress Chlamydia and are of interest for Chlamydiaceae and maybe other intracellular bacteria therapies.
    Mots-clés : Amoxicillin, Anti-Bacterial Agents, Chlamydia Infections, Chlamydia trachomatis, Drug Delivery Systems, Humans, Iron, PF, SICAPS, Trachoma, Transferrin, Vacuoles.

  • D. Hamdane, C. Velours, D. Cornu, M. Nicaise, M. Lombard, et M. Fontecave, « A chemical chaperone induces inhomogeneous conformational changes in flexible proteins », Physical chemistry chemical physics: PCCP, vol. 18, nᵒ 30, p. 20410-20421, 2016.
    Résumé : Organic osmolytes also known as chemical chaperones are major cellular compounds that favor, by an unclear mechanism, protein's compaction and stabilization of the native state. Here, we have examined the chaperone effect of the naturally occurring trimethylamine N-oxide (TMAO) osmolyte on a loosely packed protein (LPP), known to be a highly flexible form, using an apoprotein mutant of the flavin-dependent RNA methyltransferase as a model. Thermal and chemical denaturation experiments showed that TMAO stabilizes the structural integrity of the apoprotein dramatically. The denaturation reaction is irreversible indicating that the stability of the apoprotein is under kinetic control. This result implies that the stabilization is due to a TMAO-induced reconfiguration of the flexible LPP state, which leads to conformational limitations of the apoprotein likely driven by favorable entropic contribution. Evidence for the conformational perturbation of the apoprotein had been obtained through several biophysical approaches notably analytical ultracentrifugation, circular dichroism, fluorescence spectroscopy, labelling experiments and proteolysis coupled to mass spectrometry. Unexpectedly, TMAO promotes an overall elongation or asymmetrical changes of the hydrodynamic shape of the apoprotein without alteration of the secondary structure. The modulation of the hydrodynamic properties of the protein is associated with diverse inhomogenous conformational changes: loss of the solvent accessible cavities resulting in a dried protein matrix; some side-chain residues initially buried become solvent exposed while some others become hidden. Consequently, the TMAO-induced protein state exhibits impaired capability in the flavin binding process. Our study suggests that the nature of protein conformational changes induced by the chemical chaperones may be specific to protein packing and plasticity. This could be an efficient mechanism by which the cell controls and finely tunes the conformation of the marginally stable LPPs to avoid their inappropriate protein/protein interactions and aggregation.
    Mots-clés : PF, PIM, SICAPS.


  • T. N. Le Lam, C. Morvan, W. Liu, C. Bohn, Y. Jaszczyszyn, et P. Bouloc, « Finding sRNA-associated phenotypes by competition assays: An example with Staphylococcus aureus », Methods, 2016.
    Mots-clés : DBG, NGS, PF, SRRB.


  • P. Maisonnasse, E. Bouguyon, G. Piton, A. Ezquerra, C. Urien, C. Deloizy, M. Bourge, J. - J. Leplat, G. Simon, C. Chevalier, S. Vincent-Naulleau, E. Crisci, M. Montoya, I. Schwartz-Cornil, et N. Bertho, « The respiratory DC/macrophage network at steady-state and upon influenza infection in the swine biomedical model », Mucosal Immunology, vol. 9, nᵒ 4, p. 835-849, 2016.

  • L. Marty, A. Vigouroux, M. Aumont-Nicaise, Y. Dessaux, D. Faure, et S. Moréra, « Structural Basis for High Specificity of Amadori Compound and Mannopine Opine Binding in Bacterial Pathogens », The Journal of Biological Chemistry, vol. 291, nᵒ 43, p. 22638-22649, 2016.
    Résumé : Agrobacterium tumefaciens pathogens genetically modify their host plants to drive the synthesis of opines in plant tumors. Opines are either sugar phosphodiesters or the products of condensed amino acids with ketoacids or sugars. They are Agrobacterium nutrients and imported into the bacterial cell via periplasmic-binding proteins (PBPs) and ABC-transporters. Mannopine, an opine from the mannityl-opine family, is synthesized from an intermediate named deoxy-fructosyl-glutamine (DFG), which is also an opine and abundant Amadori compound (a name used for any derivative of aminodeoxysugars) present in decaying plant materials. The PBP MotA is responsible for mannopine import in mannopine-assimilating agrobacteria. In the nopaline-opine type agrobacteria strain, SocA protein was proposed as a putative mannopine binding PBP, and AttC protein was annotated as a mannopine binding-like PBP. Structural data on mannityl-opine-PBP complexes is currently lacking. By combining affinity data with analysis of seven x-ray structures at high resolution, we investigated the molecular basis of MotA, SocA, and AttC interactions with mannopine and its DFG precursor. Our work demonstrates that AttC is not a mannopine-binding protein and reveals a specific binding pocket for DFG in SocA with an affinity in nanomolar range. Hence, mannopine would not be imported into nopaline-type agrobacteria strains. In contrast, MotA binds both mannopine and DFG. We thus defined one mannopine and two DFG binding signatures. Unlike mannopine-PBPs, selective DFG-PBPs are present in a wide diversity of bacteria, including Actinobacteria, α-,β-, and γ-proteobacteria, revealing a common role of this Amadori compound in pathogenic, symbiotic, and opportunistic bacteria.
    Mots-clés : ABC transporter, B3S, Crystal Structure, DFG, host-pathogen interaction, isothermal titration calorimetry (ITC), mannopine, MESB3S, opine, periplasmic binding protein, PF, PIM, plant pathogen, x-ray crystallography.


  • J. A. Pedroza-Garcia, S. Domenichini, C. Mazubert, M. Bourge, C. White, E. Hudik, R. Bounon, Z. Tariq, E. Delannoy, I. del Olmo, M. Piñeiro, J. A. Jarillo, C. Bergounioux, M. Benhamed, et C. Raynaud, « Role of the Polymerase ϵ sub-unit DPB2 in DNA replication, cell cycle regulation and DNA damage response in Arabidopsis », Nucleic Acids Research, p. gkw449, mai 2016.


  • N. Petryk, M. Kahli, Y. d'Aubenton-Carafa, Y. Jaszczyszyn, Y. Shen, M. Silvain, C. Thermes, C. - L. Chen, et O. Hyrien, « Replication landscape of the human genome », Nature Communications, vol. 7, p. 10208, janv. 2016.

  • A. Polesskaya, G. Pinna, Y. Sassi, M. Vandamme, A. Bigot, V. Mouly, N. Morozova, A. Harel-Bellan, et C. Degerny, « Post-transcriptional modulation of interleukin 8 by CNOT6L regulates skeletal muscle differentiation », Biochimica Et Biophysica Acta (BBA) -Molecular Cell Research, vol. 1863, nᵒ 2, p. 263-270, 2016.
    Résumé : CNOT6L is a deadenylase subunit belonging to the CCR4-NOT complex, a major deadenylase complex in eukaryotes involved at multiple levels in regulation of gene expression. While CNOT6L is expressed in skeletal muscle cells, its specific functions in this tissue are still largely unknown. Our previous work highlighted the functional of CNOT6L in skeletal muscle cell differentiation. To further explore how CNOT6L regulates myogenesis, we used here gene expression analysis to identify CNOT6L mRNA targets in human myoblasts. Among these novel targets, IL-8 (interleukin 8) mRNA was the most upregulated in CNOT6L knock-down (KD) cells. Biochemical approaches and poly (A) tail length assays showed that IL-8 mRNA is a direct target of CNOT6L, and further investigations by loss- and gain-of-function assays pointed out that IL-8 is an important effector of myogenesis. Therefore, we have characterized CNOT6L-IL-8 as a new signaling axis that regulates myogenesis.
    Mots-clés : Adult, Animals, Blotting, Western, Cell Differentiation, Cell Line, Cells, Cultured, CNOT6L, DBG, Differentiation, Gene Expression Profiling, Humans, IL-8, Interleukin-8, Microscopy, Fluorescence, Muscle Development, Muscle Fibers, Skeletal, Muscle, Skeletal, Myoblasts, Myogenesis, Oligonucleotide Array Sequence Analysis, PARI, PF, Post-transcriptional regulation, Reverse Transcriptase Polymerase Chain Reaction, Ribonucleases, RNA Interference, RNA, Messenger, RPTEG, Signal Transduction, Transcription, Genetic.

  • A. Rémion, F. Khoder-Agha, D. Cornu, M. Argentini, V. Redeker, et M. Mirande, « Identification of protein interfaces within the multi-aminoacyl-tRNA synthetase complex: the case of lysyl-tRNA synthetase and the scaffold protein p38 », FEBS open bio, vol. 6, nᵒ 7, p. 696-706, 2016.
    Résumé : Human cytoplasmic lysyl-tRNA synthetase (LysRS) is associated within a multi-aminoacyl-tRNA synthetase complex (MSC). Within this complex, the p38 component is the scaffold protein that binds the catalytic domain of LysRS via its N-terminal region. In addition to its translational function when associated to the MSC, LysRS is also recruited in nontranslational roles after dissociation from the MSC. The balance between its MSC-associated and MSC-dissociated states is essential to regulate the functions of LysRS in cellular homeostasis. With the aim of understanding the rules that govern association of LysRS in the MSC, we analyzed the protein interfaces between LysRS and the full-length version of p38, the scaffold protein of the MSC. In a previous study, the cocrystal structure of LysRS with a N-terminal peptide of p38 was reported [Ofir-Birin Y et al. (2013) Mol Cell 49, 30-42]. In order to identify amino acid residues involved in interaction of the two proteins, the non-natural, photo-cross-linkable amino acid p-benzoyl-l-phenylalanine (Bpa) was incorporated at 27 discrete positions within the catalytic domain of LysRS. Among the 27 distinct LysRS mutants, only those with Bpa inserted in place of Lys356 or His364 were cross-linked with p38. Using mass spectrometry, we unambiguously identified the protein interface of the cross-linked complex and showed that Lys356 and His364 of LysRS interact with the peptide from Pro8 to Arg26 in native p38, in agreement with the published cocrystal structure. This interface, which in LysRS is located on the opposite side of the dimer to the site of interaction with its tRNA substrate, defines the core region of the MSC. The residues identified herein in human LysRS are not conserved in yeast LysRS, an enzyme that does not associate within the MSC, and contrast with the residues proposed to be essential for LysRS:p38 association in the earlier work.
    Mots-clés : cross‐link, DBG, lysyl‐tRNA synthetase, MARS, multisynthetase complex, p38, PF, protein:protein interaction, SICAPS.


  • A. Talagas, L. Fontaine, L. Ledesma-Garca, J. Mignolet, I. Li de la Sierra-Gallay, N. Lazar, M. Aumont-Nicaise, M. J. Federle, G. Prehna, P. Hols, et S. Nessler, « Structural Insights into Streptococcal Competence Regulation by the Cell-to-Cell Communication System ComRS », PLOS Pathogens, vol. 12, nᵒ 12, p. e1005980, déc. 2016.
    Mots-clés : B3S, FAAM, PF, PIM.


  • V. D. T. Tran, O. Souiai, N. Romero-Barrios, M. Crespi, et D. Gautheret, « Detection of generic differential RNA processing events from RNA-seq data », RNA Biology, vol. 13, nᵒ 1, p. 59-67, janv. 2016.
    Mots-clés : DBG, eBio, PF, SSFA.


  • M. Wery, M. Descrimes, N. Vogt, A. - S. Dallongeville, D. Gautheret, et A. Morillon, « Nonsense-Mediated Decay Restricts LncRNA Levels in Yeast Unless Blocked by Double-Stranded RNA Structure », Molecular Cell, vol. 61, nᵒ 3, p. 379-392, 2016.
    Mots-clés : DBG, eBio, PF, SSFA.

  • Z. Yi, M. Manil-Ségalen, L. Sago, A. Glatigny, V. Redeker, R. Legouis, et M. - H. Mucchielli-Giorgi, « SAFER, an Analysis Method of Quantitative Proteomic Data, Reveals New Interactors of the C. elegans Autophagic Protein LGG-1 », Journal of Proteome Research, vol. 15, nᵒ 5, p. 1515-1523, 2016.
    Résumé : Affinity purifications followed by mass spectrometric analysis are used to identify protein-protein interactions. Because quantitative proteomic data are noisy, it is necessary to develop statistical methods to eliminate false-positives and identify true partners. We present here a novel approach for filtering false interactors, named "SAFER" for mass Spectrometry data Analysis by Filtering of Experimental Replicates, which is based on the reproducibility of the replicates and the fold-change of the protein intensities between bait and control. To identify regulators or targets of autophagy, we characterized the interactors of LGG1, a ubiquitin-like protein involved in autophagosome formation in C. elegans. LGG-1 partners were purified by affinity, analyzed by nanoLC-MS/MS mass spectrometry, and quantified by a label-free proteomic approach based on the mass spectrometric signal intensity of peptide precursor ions. Because the selection of confident interactions depends on the method used for statistical analysis, we compared SAFER with several statistical tests and different scoring algorithms on this set of data. We show that SAFER recovers high-confidence interactors that have been ignored by the other methods and identified new candidates involved in the autophagy process. We further validated our method on a public data set and conclude that SAFER notably improves the identification of protein interactors.
    Mots-clés : atg-8/LC3, Autophagy, BIM, BIOCELL, C. elegans, DBG, label free mass spectrometry, OTOFAG, PF, proteomics, SICAPS, statistical methodology.

2015



  • A. - A. Arteni, M. Fradot, D. Galzerano, M. M. Mendes-Pinto, J. - A. Sahel, S. Picaud, B. Robert, et A. A. Pascal, « Structure and Conformation of the Carotenoids in Human Retinal Macular Pigment », PLOS ONE, vol. 10, nᵒ 8, p. e0135779, août 2015.
    Mots-clés : B3S, Humans, LBMS, Lutein, Macular Pigment, Molecular Conformation, PF, Retinal Pigments, SE, Spectrum Analysis, Raman, Zeaxanthins.

  • M. Bensussan, V. Lefebvre, A. Ducamp, J. Trouverie, E. Gineau, M. - N. Fortabat, A. Guillebaux, A. Baldy, D. Naquin, S. Herbette, C. Lapierre, G. Mouille, C. Horlow, et M. Durand-Tardif, « Suppression of Dwarf and irregular xylem Phenotypes Generates Low-Acetylated Biomass Lines in Arabidopsis », Plant Physiology, vol. 168, nᵒ 2, p. 452-463, 2015.
    Résumé : eskimo1-5 (esk1-5) is a dwarf Arabidopsis (Arabidopsis thaliana) mutant that has a constitutive drought syndrome and collapsed xylem vessels, along with low acetylation levels in xylan and mannan. ESK1 has xylan O-acetyltransferase activity in vitro. We used a suppressor strategy on esk1-5 to screen for variants with wild-type growth and low acetylation levels, a favorable combination for ethanol production. We found a recessive mutation in the KAKTUS (KAK) gene that suppressed dwarfism and the collapsed xylem character, the cause of decreased hydraulic conductivity in the esk1-5 mutant. Backcrosses between esk1-5 and two independent knockout kak mutants confirmed suppression of the esk1-5 effect. kak single mutants showed larger stem diameters than the wild type. The KAK promoter fused with a reporter gene showed activity in the vascular cambium, phloem, and primary xylem in the stem and hypocotyl. However, suppression of the collapsed xylem phenotype in esk1 kak double mutants was not associated with the recovery of cell wall O-acetylation or any major cell wall modifications. Therefore, our results indicate that, in addition to its described activity as a repressor of endoreduplication, KAK may play a role in vascular development. Furthermore, orthologous esk1 kak double mutants may hold promise for ethanol production in crop plants.
    Mots-clés : Acetylation, Arabidopsis, Arabidopsis Proteins, Biomass, Cell Wall, Cellulose, Ethyl Methanesulfonate, Glucuronidase, Molecular Sequence Data, Mutation, NGS, PF, Phenotype, Phloem, Plant Vascular Bundle, Suppression, Genetic, Water, Xylem.


  • C. Bourbousse, I. Mestiri, G. Zabulon, M. Bourge, F. Formiggini, M. A. Koini, S. C. Brown, P. Fransz, C. Bowler, et F. Barneche, « Light signaling controls nuclear architecture reorganization during seedling establishment », Proceedings of the National Academy of Sciences, vol. 112, nᵒ 21, p. E2836-E2844, mai 2015.
    Mots-clés : CYTO, IMAGIF, PF, PHOT.


  • M. Bourge, C. Fort, M. - N. Soler, B. Satiat-Jeunemaître, et S. C. Brown, « A pulse-chase strategy combining click-EdU and photoconvertible fluorescent reporter: tracking Golgi protein dynamics during the cell cycle », New Phytologist, vol. 205, nᵒ 2, p. 938-950, 2015.
    Mots-clés : 5-ethynyl-2′-deoxyuridine (EdU), Arabidopsis, cell cycle, Cell Proliferation, Click Chemistry, Copper, CYTO, Deoxyuridine, Fluorescence, Fluorescent Dyes, fluorescent proteins, G1 subcompartments, Golgi Apparatus, Golgi synthesis, Green Fluorescent Proteins, IMAGIF, Kaede pulse-chase, Luminescent Proteins, Molecular Imaging, PF, PHOT, Plant Proteins, Plants, Genetically Modified, Protoplasts, Tobacco, tobacco (Nicotiana tabacum) BY2 cells.


  • A. Chevrel, A. Urvoas, I. L. de la Sierra-Gallay, M. Aumont-Nicaise, S. Moutel, M. Desmadril, F. Perez, A. Gautreau, H. van Tilbeurgh, P. Minard, et M. Valerio-Lepiniec, « Specific GFP-binding artificial proteins ( Rep): a new tool for in vitro to live cell applications », Bioscience Reports, vol. 35, nᵒ 4, p. e00223-e00223, août 2015.
    Mots-clés : B3S, FAAM, MIP, PF, PIM.

  • M. Descrimes, Y. Ben Zouari, M. Wery, R. Legendre, D. Gautheret, et A. Morillon, « VING: a software for visualization of deep sequencing signals », BMC research notes, vol. 8, p. 419, 2015.
    Résumé : BACKGROUND: Next generation sequencing (NGS) data treatment often requires mapping sequenced reads onto a reference genome for further analysis. Mapped data are commonly visualized using genome browsers. However, such software are not suited for a publication-ready and versatile representation of NGS data coverage, especially when multiple experiments are simultaneously treated. RESULTS: We developed 'VING', a stand-alone R script that takes as input NGS mapping files and genome annotations to produce accurate snapshots of the NGS coverage signal for any specified genomic region. VING offers multiple viewing options, including strand-specific views and a special heatmap mode for representing multiple experiments in a single figure. CONCLUSIONS: VING produces high-quality figures for NGS data representation in a genome region of interest. It is available at http://vm-gb.curie.fr/ving/. We also developed a Galaxy wrapper, available in the Galaxy tool shed with installation and usage instructions.
    Mots-clés : Computational Biology, eBio, Genome, Genomics, High-Throughput Nucleotide Sequencing, Internet, PF, Reproducibility of Results, Sequence Analysis, DNA, Software.


  • A. El Sahili, A. Kwasiborski, N. Mothe, C. Velours, P. Legrand, S. Moréra, et D. Faure, « Natural Guided Genome Engineering Reveals Transcriptional Regulators Controlling Quorum-Sensing Signal Degradation », PLOS ONE, vol. 10, nᵒ 11, p. e0141718, nov. 2015.
    Mots-clés : 4-Butyrolactone, Amino Acid Sequence, Amino Acid Substitution, B3S, Bacterial Proteins, Carboxylic Ester Hydrolases, Circular Dichroism, Crystallography, X-Ray, Directed Molecular Evolution, Gene Expression Regulation, Bacterial, Homoserine, Lactones, MESB3S, MICROBIO, Molecular Sequence Data, Mutation, Mutation, Missense, PBI, PF, PIM, Point Mutation, Polymorphism, Single Nucleotide, Protein Conformation, Protein Folding, Quorum Sensing, Rhodococcus, Transcription Factors, Transcription, Genetic.

  • F. Eyboulet, S. Wydau-Dematteis, T. Eychenne, O. Alibert, H. Neil, C. Boschiero, M. - C. Nevers, H. Volland, D. Cornu, V. Redeker, M. Werner, et J. Soutourina, « Mediator independently orchestrates multiple steps of preinitiation complex assembly in vivo », Nucleic Acids Research, vol. 43, nᵒ 19, p. 9214-9231, 2015.
    Résumé : Mediator is a large multiprotein complex conserved in all eukaryotes, which has a crucial coregulator function in transcription by RNA polymerase II (Pol II). However, the molecular mechanisms of its action in vivo remain to be understood. Med17 is an essential and central component of the Mediator head module. In this work, we utilised our large collection of conditional temperature-sensitive med17 mutants to investigate Mediator's role in coordinating preinitiation complex (PIC) formation in vivo at the genome level after a transfer to a non-permissive temperature for 45 minutes. The effect of a yeast mutation proposed to be equivalent to the human Med17-L371P responsible for infantile cerebral atrophy was also analyzed. The ChIP-seq results demonstrate that med17 mutations differentially affected the global presence of several PIC components including Mediator, TBP, TFIIH modules and Pol II. Our data show that Mediator stabilizes TFIIK kinase and TFIIH core modules independently, suggesting that the recruitment or the stability of TFIIH modules is regulated independently on yeast genome. We demonstrate that Mediator selectively contributes to TBP recruitment or stabilization to chromatin. This study provides an extensive genome-wide view of Mediator's role in PIC formation, suggesting that Mediator coordinates multiple steps of a PIC assembly pathway.
    Mots-clés : Chromatin, DBG, Galactokinase, Gene Expression Regulation, Fungal, Genome, Fungal, GTR, Mediator Complex, Mutation, PF, RNA Polymerase II, RNA, Messenger, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, SICAPS, TATA-Box Binding Protein, Transcription Factor TFIIH, Transcription Initiation, Genetic.


  • A. Gall, A. A. Pascal, et B. Robert, « Vibrational techniques applied to photosynthesis: Resonance Raman and fluorescence line-narrowing », Biochimica et Biophysica Acta (BBA) - Bioenergetics, vol. 1847, nᵒ 1, p. 12-18, 2015.
    Mots-clés : B3S, carotenoid, Carotenoids, Chlorophyll, LBMS, Light-harvesting, PF, photosynthesis, Pigments, Biological, Reaction center, Spectrometry, Fluorescence, Spectrum Analysis, Raman, SV, Vibration.

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