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6. Cell- and Tissue-Containing Biosensors

Author

Martin-Yken, Hélène, Furger, Christophe, Toulouse Biotechnology Institute (TBI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Équipe Micro et nanosystèmes HyperFréquences Fluidiques (LAAS-MH2F), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Elsevier, Roger Narayan, Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDV.EE.SANT]Life Sciences [q-bio]/Ecology, environment/Health, Biosensors, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, [SDV]Life Sciences [q-bio], technology, industry, and agriculture, macromolecular substances, [SDV.TOX.TCA]Life Sciences [q-bio]/Toxicology/Toxicology and food chain, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Live cells and tissues
Abstract

International audience; Whole cell biosensors allow detection of modifications of a cell or a microorganism used as an integrated system. Cells and tissues from prokaryotic to higher eukaryotic origins are used as standard biosensors with two main outputs, fluorescence and bioluminescence. These living systems can be used as biosensors per se. Alternatively, their properties can be transposed by molecular engineering to any desired cell model with many applications and benefits especially in terms of access to sophisticated and accurate detection modes. Looking ahead, new developments mainly concern transposition of whole cell biosensors to the human body for monitoring and diagnosis purposes.

Published
2021

7. Ciguatera poisoning: an increasing burden for Pacific islands communities in light of climate change?

Author

Chinain, Mireille, Gatti, Clémence, Martin-Yken, Hélène, Roué, Mélanie, Darius, H, Toulouse Biotechnology Institute (TBI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut Louis Malardé [Papeete] (ILM), Institut de Recherche pour le Développement (IRD), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Pr Luis Botana, and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
Ciguatera Fish Poisoning, [SDE.MCG]Environmental Sciences/Global Changes, [SDE]Environmental Sciences, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, Climate Change Impacts, [SDV.BV.PEP]Life Sciences [q-bio]/Vegetal Biology/Phytopathology and phytopharmacy
Abstract

International audience

Published
2020

11. New biosensors to detect ciguatoxins and characterization of their binding on mammalian neuronal cell by single molecule force spectroscopy Supprimé: strategies in the detection

Author

Martin-Yken, Hélène, Chinain, M, Trévisiol, Emmanuelle, DAGUE, Etienne, Institut de Recherche pour le Développement (IRD [Polynésie]), Institut National de la Recherche Agronomique (INRA), Institut Louis Malardé [Papeete] (ILM), Institut de Recherche pour le Développement (IRD), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDE.ES]Environmental Sciences/Environmental and Society
Abstract

International audience; Ciguatera is a prominent cause of poisonings by seafood worldwide. It is caused by very potent neurotoxins, ciguatoxins (CTXs) which are lipid-soluble polyether compounds produced by dinoflagellates in the genera Gambierdiscus and Fukuyoa.. CTXs are mostly found in tropical and subtropical areas. However, both CTXs and Gambierdiscus spp. have recently been identified in European waters. CTXs bind to voltage gated sodium channels (VGSCs) at the surface of human sensory neurons where they remain, causing Ciguatera Poisoning. This severe disease is characterized by a variety of gastrointestinal, cardiovascular and neurological symptoms (paresthesia, ataxia, cold allodynia), including chronic neurological effects in some cases. Despite the wide range of tests presently available for CTXs detection, there is still no simple and rapid way of detecting these toxins in contaminated samples. In this prospect, we have engineered biosensors based on the yeast model Saccharomyces cerevisiae. This unicellular eukaryotic model is well-known and easy to genetically modify, grows fast and presents a very good conservation of signaling pathways with higher eukaryotes. Our approach relies on the detection of a transcriptional signaling activated in yeast cells by exposure to CTXs and their binding to an endogenous receptor homologous to mammalian VGSCs. New results, simplified protocol and attempts to lower down the limit of detection (LOD) will be presented. Moreover, in an attempt to use nanobiotechnology approaches, we are in parallel developing another strategy to characterize and study the binding of ciguatoxins on mammalian neuronal cells by single molecule force spectroscopy using atomic force microscopy. I will present this project and its potentialities in terms of molecular characterization of the binding between … and ex-vivo testing of inhibitor compounds. 1

Published
2019

12. Near Field infrared spectroscopy of Saccharomyces cerevisiae cell walls.Authors: Gorkem Bakir, Tanya Dahms, Hélène Martin-Yken, Hans A. Bechtel, Kathleen M. Gough

Author

Martin-Yken, Hélène, Bakir, Gorkem, Dahms, Tanya E S, Bechtel, Hans A., Gough, Kathleen, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

13. OcéaSafe : Développement de Bio-senseurs basés sur des cellules de levures

Author

Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut Louis Malardé [Papeete] (ILM), Institut de Recherche pour le Développement (IRD), Pr Nabila Gaertner-Mazouni, and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.EE]Life Sciences [q-bio]/Ecology, environment, Levures, [SDV]Life Sciences [q-bio], [SDV.TOX]Life Sciences [q-bio]/Toxicology, Ciguatera, Biosenseurs, Neurotoxines, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

14. New strategies in the fight against Ciguatera

Author

Martin-Yken, Hélène, Gironde, Camille, Darius, Hélène Taiana, Furger, Christophe, Chinain, Mireille, DAGUE, Etienne, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, [SDV]Life Sciences [q-bio], [SDE.MCG]Environmental Sciences/Global Changes, [SDE]Environmental Sciences, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; Ciguatera is the major cause of food poisonings by seafood worldwide, with an estimated 50 000 to 500 000 victims per year. It is caused by very potent neurotoxins, Ciguatoxins which are lipid-soluble polyether compounds produced by dinoflagellates from the genus Gambierdiscus spp.. Ciguatoxins are mostly found in tropical and subtropical zones, including notably the Caribbean’s, French Polynesia, New Caledonia, Indian Ocean and Southern Asia. Within the last decade, they have been also identified in fishes caught in European waters (ex.: in Madeira and Canary Islands), while Gambierdiscus spp. have also been found both in the NE Atlantic Ocean and in the Mediterranean Sea. Ciguatoxins bind to Voltage Gated Sodium Channels at the surface of human sensory neurons where they remain, causing Ciguatera Fish Poisoning or CFP. This severe disease is characterized by with a variety of gastrointestinal, cardiovascular and neurological symptoms (paresthesia, ataxia, cold allodynia), including persistent neurological effects. Despite the importance and prevalence of CFP, there is so far no simple and quick way of detecting these toxins in contaminated samples. Currently, only heavy and expensive laboratory methods are available to detect them: LC-MS/MS, receptor-binding assays by competition with radiolabeled compounds, and neuroblastoma cell-based assays performed on mammalian neurons. We have started to engineer biosensors based on the detection of a transcriptional signal in the yeast model Saccharomyces cerevisiae. This unicellular eukaryotic model is well-known and easy to genetically modify, grows fast and presents a very good conservation of signaling pathways with higher eukaryotes. Moreover, in an attempt to use developing Nanobiotechnology approaches, we will present our current strategy to study and characterize the binding of Ciguatoxins on mammalian neuronal cells by Single Molecule Force Spectroscopy using AFM.

Published
2018

15. Deconstructing and reconstructing the yeast cell wall: A top-down, bottom-up approach

Author

Dahms, Tanya E S, Körning, André, Ndlovu, Esther, Martin-Yken, Hélène, DAGUE, Etienne, UNIVERSITY OF REGINA CAN, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Synthesis, [SPI]Engineering Sciences [physics], Lysis, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Yeasts, [SDV]Life Sciences [q-bio], [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Cell wal, Atomic Force Microscopy
Abstract

International audience; Models of the Saccharomyces cerevisiae cell wall include a complex interplay of polysaccharides and proteins, with -1,3- and --1,6- glucans representing major components in terms of dry mass. The cell wall network is decorated with proteins bound to the glucans through different types of molecular interactions, including modified GPI-anchors. Chitin is another key component, which appears at the inner surface and is concentrated in bud scars, while the outer surface is coated with mannoproteins. There is a great body of evidence supporting such models; however, the precise contribution of each molecular component to the overall cell wall viscoelasticity and integrity is still an area of active investigation. The aim of this work was to examine the structural and physical properties of the S. cerevisiae cell wall during its enzymatic degradation and subsequent regeneration, using atomic force microscopy (AFM) quantitative (QI™) and high-speed (HS) imaging. We studied a wild-type strain and two well characterized cell wall mutants of S. cerevisiae, kre6, deleted in a gene required for -1,6-glucan synthesis and knr4, deprived of a cell wall signaling protein notably involved in the transcriptional control of chitin synthase genes. Clear differences between the mutant and wild type cell walls were already distinguishable by phase contrast microscopy. Spheroplasts of each strain were prepared using zymolyase and lyticase, but imaging of the perfectly round spheroplasts proved challenging, even when housed in the wells of plasma-treated PDMS stamps coated with Cell Tak. Here we present HS- and QI-AFM imaging of S. cerevisiae exposed to lyticase, showing changes to cell wall structure and physical properties in real time.References1-F. M. Klis, A. Boorsma, P. W. J. DeGroot, Journ. Yeast 23, 185 (2006).2-B. P. Reference, Rev. Name 76, 7648 (2005).Corresponding author email: tanya.dahms@uregina.ca

Published
2018

17. The Dark Side of the Wall: Atomic Force Microscopy Revelations on Drug Resistance and Adhesion

Author

Martin-Yken, Hélène, Schiavone, M, Dague, E, Formosa-Dague, Cécile, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Pr, Mritxell Riquelme, Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, GeneralLiterature_INTRODUCTORYANDSURVEY, [SDV]Life Sciences [q-bio], Drug Resistance, Biotechnologies, architecture moléculaire, InformationSystems_MODELSANDPRINCIPLES, ComputingMilieux_COMPUTERSANDEDUCATION, antifungal agent, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, Atomic Foirce Microscopy, Génie des procédés, ComputingMilieux_MISCELLANEOUS, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, réaction au stress, Human fungal pathogens, Yeast, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Process Engineering, élasticité, Adhesion, cell wall, antifongique, elasticity, candida albicans, ComputingMethodologies_GENERAL, paroi cellulaire
Abstract

International audience; The cell wall of yeast and fungi plays a crucial role in the way these cells sense, respond and adapt to environmental perturbations. Using recent Atomic Force Microscopy technological developments, the biophysical consequences of different stresses on the major human fungal pathogen, Candida albicans, were imaged and measured. Morphological changes were characterized at the nanoscale, including surface roughness, elasticity and adhesive properties. Exposure to the antifungal Caspofungin was shown to cause a deep cell wall remodeling with major modifications of chitin and beta-glucan content. Remarkably, a low dose of Caspofungin (i.e., 0.5 × MIC) provoked a strong expression of adhesive proteins on the cell surface of C. albicans, a side effect highly relevant considering its wide spread medical use. Moreover, Single Molecule Force Spectroscopy (SMFS) experiments by AFM allowed us to visualize the organization of these adhesins, to map them on the cell surface and to quantify the adhesion forces, including on cells undergoing mophogenetic differentiation. Combined with molecular biology tools, this approach enabled us to unravel the particular contribution of previously uncharacterized proteins (PGA22 and PGA59) to C. albicans adhesion mechanism. In addition, functionalizing the AFM tip with antibodies allows following the appearance of specific proteins, while precisely mapping them at the cell surface and even measuring the time scale of their progression through the cell wall. The example of Hwp1 appearance on geminating hyphal tubes will be illustrated.

Published
2017

18. Development of new biosensors to detect Ciguatoxins

Author

Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Romolo Araoz, Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, [SDE.MCG]Environmental Sciences/Global Changes, [SDV]Life Sciences [q-bio], [SDV.TOX]Life Sciences [q-bio]/Toxicology, [SDE]Environmental Sciences, [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2017

21. Knr4: a disordered hub protein at the heart of fungal cell wall signalling

Author

Martin-Yken, Hélène, François, Jean marie, Zerbib, Didier, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Saccharomyces cerevisiae Proteins, Transcription, Genetic, Protein Conformation, [SDV]Life Sciences [q-bio], Cell Cycle Checkpoints, Saccharomyces cerevisiae, Cell Wall, Humans, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Phosphorylation, Protein Processing, Post-Translational, ComputingMilieux_MISCELLANEOUS, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, Signal Transduction, Transcription Factors
Abstract

Présenté au: Fungal Cell Wall Meeting ; Paris (France) - (2015-10-01); International audience; The most highly connected proteins in protein-protein interactions networks are called hubs; they generally connect signalling pathways. In Saccharomyces cerevisiae, Knr4 constitutes a connecting node between the two main signal transmission pathways involved in cell wall maintenance upon stress: the cell wall integrity and the calcium-calcineurin pathway. Knr4 is required to enable the cells to resist many cell wall-affecting stresses, and KNR4 gene deletion is synthetic lethal with the simultaneous deletion of numerous other genes involved in morphogenesis and cell wall biogenesis. Knr4 has been shown to engage in multiple physical interactions, an ability conferred by the intrinsic structural adaptability of major disordered regions present in the N-terminal and C-terminal parts of the protein. Taking all together, Knr4 is an intrinsically disordered hub protein. Available data from other fungi indicate the conservation of Knr4 homologs cellular function and localization at sites of polarized growth among fungal species, including pathogenic species. Because of their particular role in morphogenesis control and of their fungal specificity, these proteins could constitute interesting new pharmaceutical drug targets for antifungal combination therapy.

Published
2016

22. Stress, Drug Resistance, Adhesion: the dark side of the wall

Author

Martin-Yken, Hélène, Formosa-Dague, C, Schiavone, M, François, Jean marie, DAGUE, Etienne, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV]Life Sciences [q-bio], [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, ComputingMilieux_MISCELLANEOUS, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience

Published
2016

23. Stress, Drug resistance and Adhesion: a closer look at the dark side of the wall

Author

Martin-Yken, Hélène, Formosa, Cécile, Schiavone, Marion, François, Jean marie, DAGUE, Etienne, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV]Life Sciences [q-bio], [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; Stress conditions and antifungal drugs induce significant changes in the cell wall composition of yeasts and fungi. They cause modifications of the cell wall molecular architecture, including nature, repartition and attachment of cell wall proteins to the cell surface. Atomic Force Microscopy (AFM) is a powerful tool for studying the morphology, nanomechanical and adhesive properties of live microorganisms under physiological conditions. We imaged and measured the biophysical consequences of various stresses on both S. cerevisiae and C. albicans cell morphology at the nanoscale, focusing on changes in cell surface aspect and characteristics: roughness, elasticity, and adhesive properties. AFM allowed us to unravel the morphologic effect on yeast cells of Heat Shock, Osmotic Shock, exposure to toxins and drugs. Moreover, using Single Molecule Force Spectroscopy (SMFS) we can now explore the organization of adhesins, map them on the cell surface and quantify their adhesion forces. Altogether, our studies establish the great interest of AFM to explore molecular mechanisms occurring on the cell surface of live fungal cells.

Published
2015

24. A Structural Approach to Discover an Achilles'heel of fungi : the case of Knr4/Smi1

Author

Martin-Yken, Hélène, Zerbib, Didier, Julien, Sylviane, Mourey, Lionel, Maveyraud, Laurent, François, Jean marie, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de pharmacologie et de biologie structurale (IPBS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), JP Latgé, Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

25. Drug resistance and adhesion: a closer look at the dark side of the wall

Author

Martin-Yken, Hélène, Formosa, Cécile, Dague, Etienne, François, J.M., Schiavone, Marion, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Équipe NanoBioSystèmes (LAAS-NBS), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Université Catholique de Louvain = Catholic University of Louvain (UCL), Fondazione Edmund Mach. San Michele All'adige, ITA., Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J), Université Catholique de Louvain (UCL), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, health care facilities, manpower, and services, [SDV]Life Sciences [q-bio], education, ComputingMilieux_MISCELLANEOUS, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology, health care economics and organizations
Abstract

International audience; absent

Published
2015

26. Approaching the 3D structure of a fungal conserved hub protein

Author

Martin-Yken, Hélène, Julien, Sylviane, Mourey, Lionel, François, Jean-Marie, Maveyraud, Laurent, Zerbib, D., Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Fondazione Edmund Mach. ITA., Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], [SDV.IDA]Life Sciences [q-bio]/Food engineering, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

27. Drug resistance and adhesion: a closer look into the dark side of the wall

Author

Martin-Yken, Hélène, Formosa, Cécile, Schiavone, Marion, François, Jean Marie, Dague, Etienne, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Équipe Ingénierie pour les sciences du vivant (LAAS-ELIA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), and Université de Toulouse (UT)

Subjects
Cell wall, Yeasts, [SDV]Life Sciences [q-bio], Candida albicans, Drug Resistance, Adhesion, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience; Drug resistance and adhesion:a closer look into the dark side of the wall.Hélène Martin-Yken, Cécile Formosa, Marion Schiavone, François Jean-Marie and Etienne Dague. Stress conditions and presence of drugs or antifungal compounds induce significant changes in yeast and fungi cell wall composition. The molecular architecture of the cell wall is also modified in these conditions, particularly the nature, repartition and attachment of cell wall proteins to the cell surface. Atomic Force Microscopy (AFM) is a powerful tool for studying the morphology, nanomechanical and adhesive properties of live microorganisms under physiological conditions. We took advantage of the most recent AFM technological developments to image and measure the biophysical consequences of these various stresses on C. albicans cell morphology at the nanoscale, focusing on changes in cell surface aspect and characteristics: roughness, elasticity, and adhesive properties. We notably explored the effects of the antifungal drug caspofungin used in human health1. Our investigation revealed a deep cell wall remodeling induced by this drug, evidenced by a dramatic increase in chitin and decrease in beta-glucan content. Remarkably, a low dose of caspofungin (i.e., 0.5 × MIC) also leads to a characteristic expression of adhesins on C. albicans cell surface. Moreover, in order to get a better understanding of C. albicans adhesion mechanisms, we performed Single Molecule Force Spectroscopy (SMFS) experiments to visualize the organization of adhesins and quantify the adhesion forces. We were able to map the adhesins at the cell surface and to distinguish between hydrophobic and specific affinity interactions2. Combined with molecular biology tools, this approach also enabled us to further unravel the particular contribution of previously uncharacterized proteins (PGA22 and PGA59) to C. albicans adhesion mechanism3. In the future we will focus on new approaches using Single Cell Force Spectroscopy with AFM and Optical Tweezers as well as Sheer-Stress Flow Chamber to study adhesion from the molecule scale to the population scale. 1. Formosa C. et al., 2013. Nanoscale effects of caspofungin against two yeast species; Saccharomyces cerevisiae and Candida albicans, Antimicrobial Agents and Chemotherapy, 57. 3498-3506.2. Formosa C. et al., Multiparametric Imaging of Adhesive Nanodomains at the Surface of Candida Albicans by Atomic Force Microscopy. Nanomedicine NBM, 11, 57-65.3. Cabral V. et al., Targeted changes of the cell wall proteome influence Candida albicans ability to form single- and multi-strain biofilms. PloS Pathogens.

Published
2015

28. Mapping HA-tagged protein at the surface of living cells by atomic force microscopy

Author

Formosa-Dague, Cécile, Lachaize, V., Galés, C, Rols, M P, Martin-Yken, Hélène, François, Jean-Marie, Duval, R E, DAGUE, Etienne, Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Structure et Réactivité des Systèmes Moléculaires Complexes (SRSMC), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut des Technologies Avancées en sciences du Vivant (ITAV), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut des Maladies Métaboliques et Cardiovasculaires (I2MC), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut de pharmacologie et de biologie structurale (IPBS), Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), ABC Platform, ANR young scientist program (AFMYST) ANR-11-JSV5-001-01 SD 30024331, FRM ING20140129094, 'Direction Generale de l'Armement', Toulouse University - Region Midi-Pyrenees, Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Saccharomyces cerevisiae Proteins, CHO Cells, Saccharomyces cerevisiae, yeast, Microscopy, Atomic Force, Cell Line, Fungal Proteins, GPCR, Cricetulus, [SDV.SP.MED]Life Sciences [q-bio]/Pharmaceutical sciences/Medication, Cell Wall, Influenza, Human, Protein Interaction Mapping, Animals, Humans, Membrane Glycoproteins, Cell Membrane, Atomic Force Microscopy, Receptors, Adrenergic, cell surface, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Hemagglutinins, single-molecule recognition, molecular recognition, AFM, Peptides
Abstract

Single-molecule force spectroscopy using atomic force microscopy (AFM) is more and more used to detect and map receptors, enzymes, adhesins, or any other molecules at the surface of living cells. To be specific, this technique requires antibodies or ligands covalently attached to the AFM tip that can specifically interact with the protein of interest. Unfortunately, specific antibodies are usually lacking (low affinity and specificity) or are expensive to produce (monoclonal antibodies). An alternative strategy is to tag the protein of interest with a peptide that can be recognized with high specificity and affinity with commercially available antibodies. In this context, we chose to work with the human influenza hemagglutinin (HA) tag (YPYDVPDYA) and labeled two proteins: covalently linked cell wall protein 12 (Ccw12) involved in cell wall remodeling in the yeast Saccharomyces cerevisiae and the β2-adrenergic receptor (β2-AR), a G protein-coupled receptor (GPCR) in higher eukaryotes. We first described the interaction between HA antibodies, immobilized on AFM tips, and HA epitopes, immobilized on epoxy glass slides. Using our system, we then investigated the distribution of Ccw12 proteins over the cell surface of the yeast S. cerevisiae. We were able to find the tagged protein on the surface of mating yeasts, at the tip of the mating projections. Finally, we could unfold multimers of β2-AR from the membrane of living transfected chinese hamster ovary cells. This result is in agreement with GPCR oligomerization in living cell membranes and opens the door to the study of the influence of GPCR ligands on the oligomerization process.

Published
2014

29. Knr4/Smi1 Family: Conserved Fungal Chaperones of Puzzling Origin

Author

Martin-Yken, Hélène, Richard, Mathias, François, Jean, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), INRA Centre de Versailles-Grignon, and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV]Life Sciences [q-bio], [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology
Abstract

International audience; We report here on the functional conservation of a family of fungal proteins, essentially involved in morphogenesis, cell wall synthesis and transcriptional control. The S. cerevisiae representant of this family, ScKrn4/Smi1has been the most studied and is a partially disordered protein. A strinking characteristic of this protein is the vey high number of genetic and physical partners identified so far (233, www.yeastgenome.org). Homologs of KNR4/SMI1 from various yeast species functionally complement phenotypes of the Saccharomyces cerevisiae knr4 null mutant, notably the genes from Candida albicans and Ashbya gossypii (also known as Eremothecium gossypii). The human pathogen C. albicans possesses 2 orthologs to ScKNR4/SMI1: SMI1 and SMI1B. Separate deletions of the two coding genes have been conducted and show different phenotypes (see below). The products of other homolog genes from more distant fungal species may not complement ScKnr4 function, but still display strikingly similar roles related to cell wall synthesis and cellular localization during growth (ex: Neurospora crassa GS1). CONCLUSION : Our results indicate that members of the KNR4/SMI1 gene family code for a group of chaperones, unique in the fungal kingdom, whose particular structural characteristics provide the ability to interact with several partners and to ensure a specific and conserved role in cellular morphogenesis and transcriptional control of cell wall synthesis genes. The cellular localization of these proteins during polarised growth is also characteristic and seems remarkably conserved among fungi. According to a recent structure similarity study, this gene family could originate from bacteria, and may have reached the eukaryote kingdom through viruses (Zhang, et al. Nucleic Acids Research, 4532-52 2011). ScKnr4/Smi1: an Intrinsically Unfolded Protein : PEST sequences, Interactions inhibition (most of the protein biological function) Essential when PKC1 pathway is disrupted, for interaction with calcineurin and calcineurin activity N-term: poorly structured Structured and globular C-term: unstructured 1 80 505 340 Ca Smi1 and Smi1B : Confocal fluorescence microscopy of GS-1-GFP, scale bar 5 μm. Neurospora crassa GS-1 : GS-1 gene, the Neurospora crassa homolog of ScKNR4/SMI1, was identified by complementation of a cell wall deficent mutant. GS-1 is required for the synthesis of b-1,3-glucan. (GS for Glucan Synthase, Enderlin and Selitrennikoff, PNAS USA 91, 9500-4, 1994). GS-1 protein localizes at the tip of N. crassa growing hyphae, as a sphere around the « Spitzenkörper » , a strucure essential for hyphae growth which acts as a vesicle supply center. (Verdin et al., Mol Microbiol 74, 1044-53, 2009). Even though the localization of N. crassa GS-1 and S. cerevisiae Knr4/Smi1 appears very similar, the two proteins may not be fonctionnally identical. Indeed, only the central domain (between aa 79 to 342 of ScKnr4), seems really well conserved between the two proteins, especially residues 219 to 303 which reach 57% identity. The N-and C-terminal domains, responsible for the interaction with proteic partners in ScKnr4, are more divergent. The mutant smi1-/-shows a clear hypersensitivity to CFW or SDS treatment, whereas smi1B-/-is unaffected by SDS and only slightly affected by CFW. In addition, C. albicans SMI1 gene, whose expression is induced in hyphal cells, is required for biofilm b-1,3-glucan matrix production and development of the associated drug resistance phenotype (ex: to flukonazole; Nett, et al., Curr. Opin. Microbiol. 9, 340-345, 2011).

Published
2012

30. Stochastic gene expression, phenotypic variability and adaptation of budding yeast to environmental stresses

Author

Martin-Yken, Hélène, Vuillemin, Marlène, Bigey, Frédéric, Dequin, Sylvie, Francois, J.M., Capp, Jean-Pascal, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Sciences Pour l'Oenologie (SPO), Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 1 (UM1)-Institut National de la Recherche Agronomique (INRA)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Yeasts, [SDV]Life Sciences [q-bio], Gene expression, Varibility, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011

31. Morphogenetic control of cell wall synthesis in budding yeast

Author

Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut National Polytechnique (Toulouse), Frans Klis, and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, cell wall synthesis, evolution, morphogenesis, stress response, yeast
Abstract

Morphogenesis in eukaryotes is a complex phenomenon that requires the perfect coordination of a number of different regulation and signal transduction pathways. In fungi, the cell wall determines viability, cell shape and even the function of different specialized cell types, such as mating projections, pseudohyphae and meiotic spores. I will present results obtained by investigating the cellular response to cell wall related stress in the budding yeast Saccharomyces cerevisiae, at the levels of signalling pathways, transcriptional program, biochemical composition, biophysics and morphology of the cell wall. The two major pathways that control cell wall synthesis and maintain its integrity in response to stress are the cell wall integrity (CWI) and the Calcineurin pathway. Both of these pathways also affect cell cycle regulation at different points of the yeast cell cycle. I will describe the role of a specific S. cerevisiae protein Knr4/Smi1, which takes part in both of these pathways and possibly coordinates them. This protein affects cell wall synthesis and cell cycle progression through gene regulation. It localizes at sites of polarized growth, and belongs to the family of intrinsically disordered proteins which are able to interact with multiple partners. The gene coding for this protein is conserved among fungi, as well as the protein function.

Published
2011

32. Stress pariétal et Morphogenèse chez la levure Saccharomyces cerevisiae

Author

Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2010

35. Functional dissection of an intrinsically disordered protein: Understanding the roles of different domains of Knr4 protein in protein–protein interactions

Author

Timmers Dagkessamanskaya, Adilya, Durand, Fabien, Uversky, Vladimir N., Binda, Matteo, Lopez, Frédéric, El Azzouzi, Karim, François, Jean marie, Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées, Institute for Biological Instrumentation, Russian Academy of Sciences [Moscow] (RAS), Indiana University System, Universite de Fribourg, Hôpital de Rangueil, CHU Toulouse [Toulouse], French Ministry of Research ACI-BCMS 2004-2005, National Institute of Health R01 LM007688-01A1 R01 GM071714-01A2, National Science Foundation EF 0849803, Russian Academy of Sciences, IUPUI Signature Centers Initiative, Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Université de Fribourg = University of Fribourg (UNIFR), and Centre Hospitalier Universitaire de Toulouse (CHU Toulouse)

Subjects
disordered protein regions, Saccharomyces cerevisiae Proteins, [SDV]Life Sciences [q-bio], Two-Hybrid System Techniques, [SDV.IDA]Life Sciences [q-bio]/Food engineering, protein-protein interactions, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, two-hybrid system, Surface Plasmon Resonance, intrinsically unstructured (disordered), proteins, Article, Protein Binding
Abstract

International audience; Knr4, recently characterized as an intrinsically disordered Saccharomyces cerevisiae protein, participates in cell wall formation and cell cycle regulation. It is constituted of a functional central globular core flanked by a poorly structured N-terminal and large natively unfolded C-terminal domains. Up to now, about 30 different proteins have been reported to physically interact with Knr4. Here, we used an in vivo two-hybrid system approach and an in vitro surface plasmon resonance (BIAcore) technique to compare the interaction level of different Knr4 deletion variants with given protein partners. We demonstrate the indispensability of the N-terminal domain of Knr4 for the interactions. On the other hand, presence of the unstructured C-terminal domain has a negative effect on the interaction strength. In protein interactions networks, the most highly connected proteins or "hubs" are significantly enriched in unstructured regions, and among them the transient hub proteins contain the largest and most highly flexible regions. The results presented here of our analysis of Knr4 protein suggest that these large disordered regions are not always involved in promoting the protein-protein interactions of hub proteins, but in some cases, might rather inhibit them. We propose that this type of regions could prevent unspecific protein interactions, or ensure the correct timing of occurrence of transient interactions, which may be of crucial importance for different signaling and regulation processes.

Published
2010

37. A disordered protein domain involved in morphogenesis and cell cycle progression

Author

Martin-Yken, Hélène, Dagkessamanskaia, Adilia, El Azzouzi, Karim, François, Jean marie, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2010

38. Targeted Changes of the Cell Wall Proteome Influence Candida albicans Ability to Form Single- and Multi-strain Biofilms

Author

Cabral, Vitor, primary, Znaidi, Sadri, additional, Walker, Louise A., additional, Martin-Yken, Hélène, additional, Dague, Etienne, additional, Legrand, Mélanie, additional, Lee, Keunsook, additional, Chauvel, Murielle, additional, Firon, Arnaud, additional, Rossignol, Tristan, additional, Richard, Mathias L., additional, Munro, Carol A., additional, Bachellier-Bassi, Sophie, additional, and d'Enfert, Christophe, additional

Published
2014
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39. Analyse structure-fonction de Knr4/Smi1, un nouveau membre de la famille des protéines intrinsèquement déstructurées, indispensable en l'absence de la voie PKC1/Slt2 chez Saccharomyces cerevisiae

Author

Martin-Yken, Hélène, Durand, Fabien, Timmers Dagkessamanskaya, Adilya, François, Jean marie, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2008

40. The interactome of Knr4/Smi1, a protein involved in coordinating cell wall assembly with cellular growth in yeast

Author

Martin-Yken, Hélène, Dagkessamanskaia, Adilia, Basmaji, Fadi, François, Jean marie, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Pr JP Latgé, and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2006

44. Cell Wall Stress Response and Cell Integrity Control in Saccharomyces cerevisiae

Author

Martin-Yken, Hélène, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Pr Neil Gow, and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2003

45. The yeast Saccharomyces cerevisiae cell wall: Molecular architecture, regulatory pathways and remodelling mechanisms in response to environmental conditions, and biotechnological values

Author

Martin-Yken, Hélène, Lagorce, Arnaud, François, Jean, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, [SDV]Life Sciences [q-bio], [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, [SDV.MP.MYC]Life Sciences [q-bio]/Microbiology and Parasitology/Mycology
Abstract

International audience

Published
2003

46. Involvement of GFA1, which encodes glutamine-fructose-6-phosphate amidotransferase, in the activation of the chitin synthesis pathway in response to cell-wall defects in Saccharomyces cerevisiae

Author

Lagorce, Arnaud, LE BERRE, Véronique, Aguilar-Uscanga, Blanca, Martin-Yken, Hélène, Dagkessamanskaia, Adilia, François, Jean, Institut de génétique et microbiologie [Orsay] (IGM), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Plateforme Biopuces, Génopôle Toulouse Midi-Pyrénées, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Toulouse Biotechnology Institute (TBI), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut des Technologies Avancées en sciences du Vivant (ITAV), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Unité mixte de recherche biotechnologies bioprocédés, ITAV, and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing), Transcriptional Activation, [SDV]Life Sciences [q-bio], Genes, Fungal, Molecular Sequence Data, metabolic control, Saccharomyces cerevisiae, GENETIQUE, GFA1, chitin, Gene Expression Regulation, Enzymologic, Phenotype, Carbohydrate Sequence, Gene Expression Regulation, Fungal, ENZYMZ, [SDV.BBM.GTP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Genomics [q-bio.GN], [SDV.IDA]Life Sciences [q-bio]/Food engineering, cell wall, [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, CONTROLE
Abstract

62 ref.; International audience; Cell-wall damage caused by mutations of cell-wall-related genes triggers a compensatory mechanism which eventually results in hyperaccumulation of chitin reaching 20% of the cell-wall dry mass. We show that activation of chitin synthesis is accompanied by a rise, from 1.3-fold to 3.5-fold according to the gene mutation, in the expression of most of the genes encoding enzymes of the chitin metabolic pathways. Evidence that GFA1. which encodes glutamine-fructose-6-Phosphate amidotransferase (Gfa1p), the first committed enzyme of this pathway, plays a major role in this process was as follows. Activation of chitin synthesis in the cell-wall mutants correlated with activation of GFA1 and with a proportional increase in Gfa1p activity. Overexpression of GFA1 caused an approximately threefold increase in chitin in the transformed cells, whereas chitin content was barely affected by the joint overexpression of CHS3 and CHS7. Introduction of a gfa1-97 allele mutation in the cell-wall-defective gas1-delta mutant or cultivation of this mutant in a hyperosmotic medium resulted in reduction in chitin synthesis that was proportional to the decrease in Gfa1p activity. Finally, the stimulation of chitin production was also accompanied by an increase in pools of fructose 6-Phosphate, a substrate of Gfa1p. In quantitative terms, we estimated the flux-coefficient control of Gfa1p to be in the range of 0.90, and found that regulation of the chitin metabolic pathway was mainly hierarchical, i.e. dominated by regulation of the amount of newly synthesized GFA1 protein. In the search for the mechanism by which GFA1 is activated in response to cell-wall perturbations, we could only show that neither MCM1 nor RLM1. which encode two transcriptional factors of the MADS box family that are required for expression of cell-cycle and cell-wall-related genes, was involved in this process.

Published
2002

47. Saccharomyces cerevisiae YCRO17c/CWH43 encodes a putative sensor/transporter protein upstream of the BCK2 branch of the PKC1-dependent cell wall integrity pathway

Author

Martin-Yken, Hélène, Dagkessamanskaia, Adilia, De Groot, Piet, Ram, Arthur, Klis, Frans, François, Jean, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Biocentrum Amsterdam Swammerdam Institute for Life Sciences, University of Amsterdam [Amsterdam] (UvA), Unité mixte de recherche biotechnologies bioprocédés, Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Biocentrum Amsterdam, Swammerdam Institute for Life Sciences, Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), University of Amsterdam, and Molecular Microbial Physiology (SILS, FNWI)

Subjects
Saccharomyces cerevisiae Proteins, [SDV]Life Sciences [q-bio], Green Fluorescent Proteins, Molecular Sequence Data, Saccharomyces cerevisiae, Fungal Proteins, Cell Wall, Amino Acid Sequence, cell integrity, Cloning, Molecular, Protein Kinase C, Sequence Homology, Amino Acid, PKC1, Genetic Complementation Test, Intracellular Signaling Peptides and Proteins, Epistasis, Genetic, calcofluor white hypersensitivity, Phosphoproteins, Luminescent Proteins, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Phenotype, MAP kinase, cell cycle, Sequence Alignment, Cell Division, Gene Deletion
Abstract

International audience; The Saccharomyces cerevisiae cwh43-2 mutant, originally isolated for its Calcofluor white hypersensitivity, displays several cell wall defects similar to mutants in the PKC1-MPK1 pathway, including a growth defect and increased release of b-1,6-glucan and b-glucosylated proteins into the growth medium at increased temperatures. The cloning of CWH43 showed that it corresponds to YCR017c and encodes a protein with 14-16 transmembrane segments containing several putative phosphorylation and glycosylation sites. The N-terminal part of the amino acid sequence of Cwh43p shows 40% similarity with the mammalian FRAG1, a membrane protein that activates the fibroblast growth factor receptor of rat osteosarcoma (FGFR2-ROS) and with protein sequences of four uncharacterized ORFs from Caenorhabditis elegans and one from Drosophila melanoga-ster. The C-terminus of Cwh43p shows low similarities with a xylose permease of Bacillus megaterium and with putative sugar transporter from D. melanogaster, and has 52% similarity with a protein sequence from a Schizosaccharomyces pombe cDNA. A Cwh43-GFP fusion protein suggested a plasma membrane localization, although localization to the internal structure of the cells could not be excluded, and it concentrates to the bud tip of small budded cells and to the neck of dividing cells. Deletion of CWH43 resulted in cell wall defects less pronounced than those of the cwh43-2 mutant. This allele-specific phenotype appears to be due to a G-R substitution at position 57 in a highly conserved region of the protein. Genetic analysis places CWH43 upstream of the BCK2 branch of the PKC1 signalling pathway, since cwh43 mutations were synthetic lethal with pkc1 deletion, whereas the cwh43 defects could be rescued by overexpression of BCK2 and not by high-copy-number expression of genes encoding downstream proteins of the PKC1 pathway. However, unlike BCK2, whose disruption in a cln3 mutant resulted in growth arrest in G 1 , no growth defect was observed in a double cwh43 cln3 mutants. Taken together, it is proposed that CWH43 encodes a protein with putative sensor and transporter domains acting in parallel to the main PKC1-dependent cell wall integrity pathway, and that this gene has evolved into two distinct genes in higher eukaryotes.

Published
2001

48. 10th Francophone Yeast Meeting ‘Levures, Modèles & Outils’

Author

Martin-Yken, Hélène, primary, Ribaud, Virginie, additional, Poli, Jérôme, additional, Hoareau-Aveilla, Coralie, additional, Spichal, Maya, additional, Beaufort, Sandra, additional, Tilloy, Valentin, additional, Delerue, Thomas, additional, Capp, Jean-Pascal, additional, and Parrou, Jean-Luc, additional

Published
2012
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50. Crystallographic studies of the structured core domain of Knr4 from Saccharomyces cerevisiae.

Author

Julien, Sylviane, Tondl, Patrick, Durand, Fabien, Dagkessamanskaia, Adilia, van Tilbeurgh, Herman, François, Jean Marie, Mourey, Lionel, Zerbib, Didier, Martin-Yken, Hélène, and Maveyraud, Laurent

Subjects
SACCHAROMYCES cerevisiae, PROTEINS, ESCHERICHIA coli, SELENIUM, ELECTRON density
Abstract

The potentially structured core domain of the intrinsically disordered protein Knr4 from Saccharomyces cerevisiae, comprising residues 80-340, was expressed in Escherichia coli and crystallized using the hanging-drop vapour-diffusion method. Selenomethionine-containing (SeMet) protein was also purified and crystallized. Crystals of both proteins belonged to space group P6522, with unit-cell parameters a = b = 112.44, c = 265.21 Å for the native protein and a = b = 112.49, c = 262.21 Å for the SeMet protein, and diffracted to 3.50 and 3.60 Å resolution, respectively. There are two molecules in the asymmetric unit related by a twofold axis. The anomalous signal of selenium was recorded and yielded an electron-density map of sufficient quality to allow the identification of secondary-structure elements. [ABSTRACT FROM AUTHOR]

Published
2015
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