DOCSLIB.ORG

Involvement of Ceramide in Hyperosmotic Shock- Induced Death of Erythrocytes

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Involvement of Ceramide in Hyperosmotic Shock- Induced Death of Erythrocytes Cell Death and Differentiation (2004) 11, 231–243 & 2004 Nature Publishing Group All rights reserved 1350-9047/04 $25.00 www.nature.com/cdd Involvement of ceramide in hyperosmotic shock- induced death of erythrocytes KS Lang1, S Myssina1, V Brand1, C Sandu1, PA Lang1, Introduction S Berchtold1, SM Huber1, F Lang*,1 and T Wieder1 Apoptosis is a physiological form of death in which cells turn 1 Department of Physiology, University of Tu¨bingen, Gmelinstr. 5, 72076 on a program eventually leading to self-destruction. It has Tu¨bingen, Germany been shown that the loss of cell volume is an early and * Corresponding author: F Lang, Physiologisches Institut der Universita¨t fundamental feature of this form of cell death (for reviews, see Tu¨bingen, Gmelinstr. 5, Tu¨bingen D-72076, Germany. Gomez-Angelats et al.1 and Gomez-Angelats and Cidlows- Tel: þ 49 7071 29 72194; Fax: þ 49 7071 29 5618; ki2). Among the well-known triggers of apoptotic cell death is E-mail: fl[email protected] osmotic shock, that is, exposure to hypertonic extracellular fluid.3–5 The cellular mechanisms invoked in the triggering of Received 20.11.02; revised 27.5.03; accepted 04.7.03; published online 14.11.03 apoptosis following osmotic shock have been intensively Edited by RA Kolesnick studied in nucleated cells. These mechanisms include ligand- independent clustering of multiple growth factor and cytokine Abstract receptors, such as tumor necrosis factor receptor, by physical stress,6 upregulation of tumor necrosis factor-alpha expres- Erythrocytes lack nuclei and mitochondria, the organelles sion3 and triggering of death receptor membrane trafficking.7 important for apoptosis of nucleated cells. However, following These plasma membrane-located signals are then trans- 2 þ increase of cytosolic Ca activity, erythrocytes undergo cell duced by a network of different pathways, for example, shrinkage, cell membrane blebbing and breakdown of activation of the phosphatidylinositol 3-kinase/Akt pathway,8 phosphatidylserine asymmetry, all features typical for induction of transcriptionally active p534 and activation of the apoptosis in nucleated cells. The same events are observed heat-shock transcription factor 1.9 Further studies pointed to a following osmotic shock, an effect mediated in part by significant role of mitochondria during osmotic stress, either 2 þ as a stress-sensing module10 or as part of the apoptotic activation of Ca -permeable cation channels. However, 11 erythrocyte death following osmotic shock is blunted but not pathway itself. This plasticity of effects involved in apoptotic pathways stimulated the search for less complex systems that prevented in the absence of extracellular Ca2 þ pointing to are able to operate in the absence of intracellular organelles or additional mechanisms. As shown in this study, osmotic gene transcription. shock (950 mOsm) triggers sphingomyelin breakdown and Erythrocytes are devoid of nuclei and mitochondria, formation of ceramide. The stimulation of annexin binding intracellular organelles involved in the induction of apoptosis following osmotic shock is mimicked by addition of ceramide of nucleated cells.12,13 Nevertheless, elevation of intracellular or purified sphingomyelinase and significantly blunted by Ca2 þ activity by treatment of erythrocytes with the Ca2 þ genetic (aSM-deficient mice) or pharmacologic (50 lM 3,4- ionophore ionomycin induces erythrocyte shrinkage, mem- dichloroisocoumarin) knockout of sphingomyelinase. The brane blebbing and breakdown of cell membrane phospha- 14–16 effect of ceramide is blunted but not abolished in the absence tidylserine asymmetry, all typical features of apoptosis in 2 þ nucleated cells. Thus, the postulate has been made that those of Ca . Conversely, osmotic shock-induced annexin bind- 14–16 ing is potentiated in the presence of sublethal concentrations events reflect erythrocyte apoptosis. The exposure of phosphatidylserine at the surface is evidenced from binding of of ceramide. In conclusion, ceramide and Ca2 þ entry through annexin.14,15 Most recently, erythrocytes have similarly been cation channels concert to trigger erythrocyte death during shown to bind annexin following osmotic shock,17 which osmotic shock. activates a Ca2 þ -permeable cation channel, thus leading to Cell Death and Differentiation (2004) 11, 231–243. doi:10.1038/ increase of cytosolic Ca2 þ activity.17 Intracellular Ca2 þ then sj.cdd.4401311 activates a scramblase that translocates phosphatidylserine Published online 14 November 2003 to the outer leaflet of the cell membrane.18,19 However, erythrocyte annexin binding following osmotic shock is only Keywords: cell volume; osmotic cell shrinkage; annexin; sphin- partially inhibited in the nominal absence of Ca2 þ or in the 17 gomyelinase; calcium presence of a cation channel inhibitor. Thus, osmotic shock is likely to trigger additional mechanisms eventually leading to breakdown of phosphatidylserine asymmetry. The present Abbreviations: C6-ceramide, D-erythro-N-hexanoylsphingo- sine; DMSO, dimethyl sulfoxide; EGTA, ethylene glycol-bis (b- study aimed to disclose those additional mechanisms. As aminoethyl ether)-N,N,N0N0-tetraacetic acid; FCS, fetal calf activation of acidic sphingomyelinase (aSMase) with subse- serum; FITC, fluorescein isothiocyanate; HEPES, N-2-hydro- quent formation of ceramide participates in the signaling of 20,21 xyethylpiperazine-N-2-ethanesulfonic acid; PBS, phosphate-buf- CD95-induced apoptosis of nucleated cells and as CD95 7 fered saline; SM, sphingomyelin; SMase, sphingomyelinase has also been implicated in the osmotic stress response, we specifically explored the influence of ceramide on erythrocyte apoptosis. Ceramide triggering erythrocyte apoptosis KS Lang et al 232 Results treated with 950 mOsm in the presence of Ca2 þ and 33.876.1% (n¼4) for cells treated with 950 mOsm in the 2 þ Ca ionophore ionomycin and hyperosmolarity absence of Ca2 þ (Figure 3b). As illustrated in Figure 3b, the trigger erythrocyte annexin binding annexin binding triggered by osmotic shock in the presence of Treatment of erythrocytes with the Ca2 þ ionophore ionomycin (1 mM) increases, within 1 h, the percentage of annexin binding cells from 1.470.4 to 73.477.7% (n¼4). Thus, increase of intracellular calcium leads to breakdown of phosphatidylserine asymmetry. As illustrated in Figure 1a, annexin binding of erythrocytes is further increased following an 8-h exposure to hypertonic extracellular fluid (600 and 950 mOsm). In the following experiments, we routinely used 950 mOsm to induce annexin binding. In contrast to Jurkat T- cells, phosphatidylserine exposure in erythrocytes is not caspase-dependent. The pan-caspase inhibitor zVAD-fmk reduces annexin binding after osmotic shock in Jurkat cells (Figure 1c) but not in erythrocytes (Figure 1b). Furthermore, although erythrocytes contain significant amounts of procas- pase-3, limited proteolysis of the enzyme to the active p17 subunit of caspase-3 did not occur after osmotic shock (Figure 2b, c). Again, Jurkat T-cells served as a positive control and these cells clearly displayed osmotic shock-induced formation of the active p17 subunit (Figure 2a). The morphology of erythrocytes exposed to osmotic shock is shown in Figure 3a. The cells are shrunken, annexin-positive and show invagina- tions of the plasma membrane. If erythrocyte membrane integrity is disrupted, then annexin could bind to phosphatidylserine facing the cytosol. Disruption of the erythrocyte cell membrane should lead to release of cellular proteins including hemoglobin. To test for this possibility, we determined hemoglobin release. An 8-h exposure to 950 mOsm led to the release of hemoglobin from only 3.870.6% (n¼4) of the erythrocytes. Thus, the erythro- cyte cell membrane is not disrupted and annexin would not have access to the intracellular leaflet of the cell membrane. This was further confirmed in erythrocytes infected with Plasmodium falciparum and counterstained with propidium iodide: after an 8-h treatment with 950 mOsm 78.272.3% (n¼3) of the infected cells were annexin-positive and 82.277.3% (n¼3) were propidium iodide-negative. We then investigated the Ca2 þ dependence of erythrocyte death. In the nominal absence of extracellular Ca2 þ annexin binding following osmotic shock has been significantly decreased but not abolished. The respective values were 3.170.4% (n¼4) for controls, 58.574.0% (n¼4) for cells Figure 1 Hyperosmotic shock induces caspase-independent annexin binding of erythrocytes. (a) Annexin binding of erythrocytes at different osmolarities after 8 h of incubation. Arithmetic means7S.E.M. (n¼3) of annexin-positive cells are given in % of the total population. (b) Annexin binding of erythrocytes after 8 h of incubation with 950 mOsm in the absence or presence of 25 or 50 mM zVAD-fmk. Control refers to erythrocytes exposed to an isotonic buffer solution (300 mOsm) for 8 h. Arithmetic means7S.E.M. (n¼3) of annexin-positive cells are given in % of the total population. (c) Annexin binding of Jurkat T-cells after 8 h of incubation with 950 mOsm in the absence or presence of 25 or 50 mM zVAD-fmk. Control refers to Jurkat T-cells exposed to isotonic medium (300 mOsm) for 8 h. Arithmetic means7S.E.M. (n¼3) of annexin-positive/propidium iodide-negative cells are given in % of the total population. ***Significantly different from cells treated with 950 mOsm in the absence of zVAD-fmk (Po0.01) Cell Death and Differentiation Ceramide triggering erythrocyte apoptosis KS Lang et al 233 Figure 2 Hyperosmotic shock does not induce caspase-3 activation in erythrocytes. (a) Jurkat T-cells were treated either with isotonic medium (300 mOsm) or with medium adjusted to 700 mOsm. Then, 25 mg of cellular extract was loaded per lane and activation of caspase-3 was analyzed by Western blot as described in Materials and Methods. (b) Erythrocytes were treated either with isotonic medium (300 mOsm) or with medium adjusted to 700 or 950 mOsm. Then, 300 mg of cellular extract was loaded per lane and activation of caspase-3 was analyzed by Western blot. (c) Erythrocytes were treated either with isotonic medium (300 mOsm) or with medium adjusted to 700 or 950 mOsm.
Load more

Recommended publications
  • Multifaceted Chaudhry.Pdf
    Neuropharmacology 161 (2019) 107789 Contents lists available at ScienceDirect Neuropharmacology journal homepage: www.elsevier.com/locate/neuropharm Invited review Multifaceted regulation of the system A transporter Slc38a2 suggests T nanoscale regulation of amino acid metabolism and cellular signaling ∗ Robin Johansen Menchinia, , Farrukh Abbas Chaudhrya,b a Department of Molecular Medicine, University of Oslo, Oslo, Norway b Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway HIGHLIGHTS • Slc38a2 represents the classically described system A transport activity. • Slc38a2 accumulates small, neutral amino acids directly or indirectly by energizing ASCT1/2 and LAT1/2 transporters. • Slc38a2 is extensively regulated by cell stress, nutritional and hormonal signaling, and acts as an amino acid sensor upstream of mTOR. • Slc38a2 contributes to the pathology in a number of diseases such as cancer, epilepsy and diabetes mellitus. ARTICLE INFO ABSTRACT Keywords: Amino acids are essential for cellular protein synthesis, growth, metabolism, signaling and in stress responses. Slc38a1 Cell plasma membranes harbor specialized transporters accumulating amino acids to support a variety of cellular Slc38a2 biochemical pathways. Several transporters for neutral amino acids have been characterized. However, Slc38a2 SNAT2 (also known as SA1, SAT2, ATA2, SNAT2) representing the classical transport system A activity stands in a Glutamine unique position: Being a secondarily active transporter energized by the electrochemical gradient of Na+, it Osmoregulation creates steep concentration gradients for amino acids such as glutamine: this may subsequently drive the ac- Adaptive regulation cumulation of additional neutral amino acids through exchange via transport systems ASC and L. Slc38a2 is ubiquitously expressed, yet in a cell-specific manner. In this review, we show that Slc38a2 is regulated atthe transcriptional and translational levels as well as by ions and proteins through direct interactions.
    [Show full text]
  • The Externally Derived Portion of the Hyperosmotic Shock-Activated Cytosolic Calcium Pulse Mediates Adaptation to Ionic Stress in Suspension-Cultured Tobacco Cells
    ARTICLE IN PRESS Journal of Plant Physiology 164 (2007) 815—823 www.elsevier.de/jplph The externally derived portion of the hyperosmotic shock-activated cytosolic calcium pulse mediates adaptation to ionic stress in suspension-cultured tobacco cells Stephen G. Cessnaa,Ã, Tracie K. Matsumotob, Gregory N. Lamba, Shawn J. Ricea,1, Wendy Wenger Hochstedlera,2 aDepartments of Biology and Chemistry, Eastern Mennonite University, 1200 Park Road, Harrisonburg, VA 22802, USA bUSDA-ARS-PWA-PBARC, Tropical Plant Genetic Resource Management Unit, Hilo, HI, USA Received 9 October 2006; received in revised form 16 November 2006; accepted 27 November 2006 KEYWORDS Summary Aequorin; The influx of Ca2+ into the cytosol has long been suggested to serve as a signaling Calcium; intermediate in the acquisition of tolerance to hyperosmotic and/or salinity stresses. Inositol-1,4,5-tris- Here we use aequorin-transformed suspension-cultured tobacco cells to directly phosphate; assess the role of cytosolic calcium (Ca2+ ) signaling in salinity tolerance acquisition. Salinity; cyt Aequorin luminescence recordings and 45Ca influx measurements using inhibitors of Signal transduction Ca2+ influx (Gd3+ and the Ca2+-selective chelator EGTA), and modulators of organellar Ca2+ release (phospholipase C inhibitors U73122 or neomycin) demonstrate that hyperosmolarity, whether imposed by NaCl or by a non-ionic molecule sorbitol, 2+ 2+ induces a rapid (returning to baseline levels of Ca within 10 min) and complex Cacyt pulse in tobacco cells, deriving both from Gd3+-sensitive externally derived Ca2+ influx and from U73122- and neomycin-sensitive Ca2+ release from an organelle. To determine whether each of the two components of this brief Ca2+ signal regulate adaptation to hyperosmotic shock, the Ca2+ pulse was modified by the addition of Gd3+, U73122, neomycin, or excess Ca2+, and then cells were treated with salt or sorbitol.
    [Show full text]
  • Intracellular Potassium Depletion Enhances Apoptosis Induced by Staurosporine in Cultured Trigeminal Satellite Glial Cells
    SOMATOSENSORY & MOTOR RESEARCH https://doi.org/10.1080/08990220.2021.1941843 ARTICLE Intracellular potassium depletion enhances apoptosis induced by staurosporine in cultured trigeminal satellite glial cells Hedie A. Bustamantea, Marion F. Ehrichb and Bradley G. Kleinb aFaculty of Veterinary Sciences, Veterinary Clinical Sciences Institute, Universidad Austral de Chile, Valdivia, Chile; bDepartment of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA ABSTRACT ARTICLE HISTORY Purpose: Satellite glial cells (SGC) surrounding neurons in sensory ganglia can buffer extracellular Received 4 June 2021 potassium, regulating the excitability of injured neurons and possibly influencing a shift from acute to Accepted 8 June 2021 neuropathic pain. SGC apoptosis may be a key component in this process. This work evaluated induc- KEYWORDS tion or enhancement of apoptosis in cultured trigeminal SGC following changes in intracellular potas- Satellite glial cells; sium [K]ic. apoptosis; staurosporine; Materials and methods: We developed SGC primary cultures from rat trigeminal ganglia (TG). Purity neuropathic pain of our cultures was confirmed using immunofluorescence and western blot analysis for the presence of the specific marker of SGC, glutamine synthetase (GS). SGC [K]ic was depleted using hypo-osmotic shock and 4 mM bumetanide plus 10 mM ouabain. [K]ic was measured using the Kþ fluorescent indica- tor potassium benzofuran isophthalate (PBFI-AM). Results: SGC tested positive for GS and hypo-osmotic shock induced a significant decrease in [K]ic at every evaluated time. Cells were then incubated for 5 h with either 2 mM staurosporine (STS) or 20 ng/ ml of TNF-a and evaluated for early apoptosis and late apoptosis/necrosis by flow cytometry using annexin V and propidium iodide.
    [Show full text]
  • Osmoadaptation Mechanisms of Cyanobacteria and Archaea from the Stromatolites of Hamelin Pool, Western Australia
    Osmoadaptation mechanisms of cyanobacteria and archaea from the stromatolites of Hamelin Pool, Western Australia Falicia Qi Yun Goh B. Sc (Hons.) UNSW A Dissertation Submitted in Fulfilment of the Requirements for the degree of Doctor of Philosophy School of Biotechnology and Biomolecular Sciences The University of New South Wales Sydney, Australia 2007 Osmoadaptation mechanisms of cyanobacteria and archaea from the stromatolites of Hamelin Pool, Western Australia Falicia Qi Yun Goh B. Sc (Hons.) (UNSW) A Dissertation Submitted in Partial Fulfilment of the Requirements for the degree of Doctor of Philosophy School of Biotechnology and Biomolecular Sciences The University of New South Wales Sydney, Australia Supervisors Prof. Brett A. Neilan Dr. Brendan P. Burns School of Biotechnology and Biomolecular Sciences The University of New South Wales Sydney, Australia Certificate of originality Abstract The stromatolites of Shark Bay Western Australia, located in a hypersaline environment, is an ideal biological system for studying survival strategies of cyanobacteria and halophilic archaea to high salt and their metabolic cooperation with other bacteria. To-date, little is known of the mechanisms by which these stromatolite microorganisms adapt to hypersalinity. To understand the formation of these sedimentary structures, detailed analysis of the microbial communities and their physiology for adaptation in this environment are crucial. In this study, microbial communities were investigated using culturing and molecular methods. Phylogenetic analysis of the 16S rRNA gene was carried out to investigate the diversity of microorganisms present. Unique phylotypes from the bacteria, cyanobacteria and archaea clone libraries were identified. Representative cyanobacteria isolates and Halococcus hamelinensis, a halophilic archaea isolated from in this study, were the focus for identifying osmoadaptation mechanisms.
    [Show full text]
  • The Mechanosensitive Ion Channel MSL10 Potentiates Responses to Cell Swelling in 2 Arabidopsis Seedlings 3 4 5 6 AUTHORS/AFFILIATIONS 7 Debarati Basu and Elizabeth S
    bioRxiv preprint doi: https://doi.org/10.1101/2020.04.02.021683; this version posted April 3, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 TITLE: The Mechanosensitive Ion Channel MSL10 Potentiates Responses to Cell Swelling in 2 Arabidopsis Seedlings 3 4 5 6 AUTHORS/AFFILIATIONS 7 Debarati Basu and Elizabeth S. Haswell* 8 NSF Center for Engineering Mechanobiology, Dept. of Biology, Washington University in St. 9 Louis, St. Louis MO 63130 10 11 *corresponding author 12 13 CONTACT INFORMATION 14 [email protected] +1 314 935-9223 15 16 17 Key words: Programmed cell death, cell swelling, hypo-osmotic, mechanosensitive, reactive 18 oxygen species 1 bioRxiv preprint doi: https://doi.org/10.1101/2020.04.02.021683; this version posted April 3, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 19 SUMMARY 20 The ability to respond to unanticipated increases in volume is a fundamental property of cells, 21 essential for cellular integrity in the face of osmotic challenges. Plants must manage cell swelling 22 during flooding, rehydration, and pathogenesis–but little is known about the mechanisms by which 23 this occurs. It has been proposed that plant cells could sense and respond to cell swelling through 24 the action of mechanosensitive ion channels. Here we develop and characterize a new assay to 25 study the effects of cell swelling on Arabidopsis thaliana seedlings and to test the contributions of 26 the mechanosensitive ion channel MscS-Like10 (MSL10).
    [Show full text]
  • Quantitative Coupling of Cell Volume and Membrane Tension During Osmotic Shocks
    bioRxiv preprint doi: https://doi.org/10.1101/2021.01.22.427801; this version posted January 25, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Quantitative coupling of cell volume and membrane tension during osmotic shocks Chloe´ Roffay1, Guillaume Molinard1, Kyoohyun Kim2, Victoria Barbarassa1, Marta Urbanska2, Vincent Mercier1, Jose´ Garc´ıa-Calvo3, Stefan Matile3,4, Jochen Guck2, Martin Lenz5, and Aurelien´ Roux1,3,* 1Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland 2Max Planck Institute for the Science of Light & Max-Planck-Zentrum fur¨ Physik und Medizin, Staudtstraße 2, DE-91058 Erlangen, Germany 3School of Chemistry and Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland 4National Centre of Competence in Research (NCCR) Chemical Biology, University of Geneva, CH-1211 Geneva, Switzerland 5Universite´ Paris-Saclay, CNRS, LPTMS, 91405, Orsay, France; PMMH, CNRS, ESPCI Paris, PSL University, Sorbonne Universite,´ Universite´ de Paris, F-75005, Paris, France *correspondence to : [email protected] ABSTRACT During osmotic changes of their environment, cells actively regulate their volume and plasma membrane tension that can passively change through osmosis. How tension and volume are coupled during osmotic adaptation remains unknown, as a quantitative characterization is lacking. Here, we performed dynamic membrane tension and cell volume measurements during osmotic shocks. During the first few seconds following the shock, cell volume varied to equilibrate osmotic pressures inside and outside the cell, and membrane tension dynamically followed these changes. A theoretical model based on the passive, reversible unfolding of the membrane as it detaches from the actin cortex during volume increase, quantitatively describes our data.
    [Show full text]
  • Signal Transduction Pathways Regulated by Arsenate and Arsenite
    Oncogene (1999) 18, 7794 ± 7802 ã 1999 Stockton Press All rights reserved 0950 ± 9232/99 $15.00 http://www.stockton-press.co.uk/onc Signal transduction pathways regulated by arsenate and arsenite Amy C Porter1, Gary R Fanger2,3 and Richard R Vaillancourt*,1 1Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, Arizona, AZ 85721-0207, USA; 2Program in Molecular Signal Transduction, Division of Basic Sciences, National Jewish Medical and Research Center, Denver, Colorado, CO 80206, USA Arsenate and arsenite activate c-Jun N-terminal kinase c-Jun, which forms a heterodimer with c-Fos to form (JNK), however, the mechanism by which this occurs is the AP-1 transacting factor. Activation of JNK is not known. By expressing inhibitory mutant small GTP- commonly associated with inhibition of cell growth binding proteins, p21-activated kinase (PAK) and and/or apoptosis (Kyriakis and Avruch, 1996). mitogen-activated protein kinase/extracellular signal- However, under certain circumstances, sustained JNK regulated kinase kinase kinases (MEKKs), we have activation, as opposed to transient activation, is identi®ed speci®c proteins that are involved in arsenate- required for an apoptotic response (Guo et al., 1998). and arsenite-mediated activation of JNK. We observe a Toxic doses of inorganic arsenicals, such as arsenite distinct dierence between arsenate and arsenite signal- and arsenate, produce pleiotrophic eects. Using ing, which demonstrates that arsenate and arsenite are cultured macrophages as an in vitro system to study capable of activating unique proteins. Both arsenate and arsenic toxicity, it was observed that 80% of the dead arsenite activation of JNK requires Rac and Rho.
    [Show full text]
  • Institutional Repository - Research Portal Dépôt Institutionnel - Portail De La Recherche
    Institutional Repository - Research Portal Dépôt Institutionnel - Portail de la Recherche University of Namurresearchportal.unamur.be RESEARCH OUTPUTS / RÉSULTATS DE RECHERCHE The osmotic demyelination syndrome GILLOTEAUX, Jacques; Bouchat, Joanna; Brion, Jean Pierre; Nicaise, Charles Published in: Ultrastructural Pathology Author(s) - Auteur(s) : Publication date: 2020 Document Version PublicationPeer reviewed date version - Date de publication : Link to publication Citation for pulished version (HARVARD): GILLOTEAUX, J, Bouchat, J, Brion, JP & Nicaise, C 2020, 'The osmotic demyelination syndrome: the resilience Permanentof thalamic link neurons - Permalien is verified with: transmission electron microscopy', Ultrastructural Pathology. Rights / License - Licence de droit d’auteur : General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately
    [Show full text]
  • Proteins in the Periplasmic Space and Outer Membrane Vesicles of Rhizobium Etli CE3 Grown in Minimal Medium Are Largely Distinct
    bioRxiv preprint doi: https://doi.org/10.1101/305797; this version posted April 21, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 2 Proteins in the periplasmic space and outer membrane vesicles of Rhizobium etli CE3 3 grown in minimal medium are largely distinct and change with growth phase 4 5 Hermenegildo Taboada1,&, Niurka Meneses1,2,3,&, Michael F. Dunn1&, Carmen Vargas- 6 Lagunas1, Natasha Buchs2, Jaime A. Castro-Mondragon4, Manfred Heller2 and Sergio 7 Encarnación1*. 8 9 &These authors contributed equally to this work. 10 11 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, 12 Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, 13 México. 14 2Mass Spectrometry and Proteomics Laboratory, Department of Clinical Research, 15 University of Bern, 3010 Bern, Switzerland. 16 3Faculty of Science, Department of Chemistry and Biochemistry, University of Bern, 17 3010 Bern, Switzerland. 18 4Aix Marseille University, INSERM, TAGC, Theory and Approaches of Genomic Complexity, 19 UMR_S 1090, Marseille, France. 20 21 22 Corresponding author: [email protected], +52 (777) 3291899 23 24 KEY WORDS 25 Protein secretion, outer membrane vesicles, periplasm, exoproteome, Rhizobium-legume 26 interactions 27 28 1 bioRxiv preprint doi: https://doi.org/10.1101/305797; this version posted April 21, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
    [Show full text]
  • Responses of Microorganisms to Osmotic Stress
    MI73CH15_Bremer ARjats.cls August 5, 2019 14:49 Annual Review of Microbiology Responses of Microorganisms to Osmotic Stress Erhard Bremer1 and Reinhard Krämer2 1Laboratory for Microbiology, Department of Biology; and Center for Synthetic Microbiology, Philipps-Universität Marburg, 35043 Marburg, Germany; email: [email protected] 2Institute of Biochemistry, University of Cologne, 50674 Cologne, Germany; email: [email protected] Annu. Rev. Microbiol. 2019. 73:313–34 Keywords First published as a Review in Advance on osmoregulation, osmosensing, osmoprotectants, transporters and channels, June 10, 2019 c-di-AMP, biofilms The Annual Review of Microbiology is online at micro.annualreviews.org Abstract https://doi.org/10.1146/annurev-micro-020518- The cytoplasm of bacterial cells is a highly crowded cellular compartment 115504 that possesses considerable osmotic potential. As a result, and owing to the Annu. Rev. Microbiol. 2019.73:313-334. Downloaded from www.annualreviews.org Copyright © 2019 by Annual Reviews. semipermeable nature of the cytoplasmic membrane and the semielastic Access provided by WIB6100 - University of Marburg on 09/10/19. For personal use only. All rights reserved properties of the cell wall, osmotically driven water influx will generate tur- gor, a hydrostatic pressure considered critical for growth and viability. Both increases and decreases in the external osmolarity inevitably trigger water fluxes across the cytoplasmic membrane, thus impinging on the degreeof cellular hydration, molecular crowding, magnitude of turgor, and cellular integrity. Here, we assess mechanisms that permit the perception of osmotic stress by bacterial cells and provide an overview of the systems that allow them to genetically and physiologically cope with this ubiquitous environ- mental cue.
    [Show full text]
  • Genome Analysis of a Halophilic Bacterium Halomonas Malpeensis YU‑PRIM‑29T Reveals Its Exopolysaccharide and Pigment Producing Capabilities Athmika1,2, Sudeep D
    www.nature.com/scientificreports OPEN Genome analysis of a halophilic bacterium Halomonas malpeensis YU‑PRIM‑29T reveals its exopolysaccharide and pigment producing capabilities Athmika1,2, Sudeep D. Ghate1,2, A. B. Arun1, Sneha S. Rao1, S. T. Arun Kumar1, Mrudula Kinarulla Kandiyil1, Kanekar Saptami1 & P. D. Rekha1* Halomonas malpeensis strain YU‑PRIM‑29T is a yellow pigmented, exopolysaccharide (EPS) producing halophilic bacterium isolated from the coastal region. To understand the biosynthesis pathways involved in the EPS and pigment production, whole genome analysis was performed. The complete genome sequencing and the de novo assembly were carried out using Illumina sequencing and SPAdes genome assembler (ver 3.11.1) respectively followed by detailed genome annotation. The genome consists of 3,607,821 bp distributed in 18 contigs with 3337 protein coding genes and 53% of the annotated CDS are having putative functions. Gene annotation disclosed the presence of genes involved in ABC transporter‑dependent pathway of EPS biosynthesis. As the ABC transporter‑ dependent pathway is also implicated in the capsular polysaccharide (CPS) biosynthesis, we employed extraction protocols for both EPS (from the culture supernatants) and CPS (from the cells) and found that the secreted polysaccharide i.e., EPS was predominant. The EPS showed good emulsifying activities against the petroleum hydrocarbons and its production was dependent on the carbon source supplied. The genome analysis also revealed genes involved in industrially important metabolites such as zeaxanthin pigment, ectoine and polyhydroxyalkanoate (PHA) biosynthesis. To confrm the genome data, we extracted these metabolites from the cultures and successfully identifed them. The pigment extracted from the cells showed the distinct UV–Vis spectra having characteristic absorption peak of zeaxanthin (λmax 448 nm) with potent antioxidant activities.
    [Show full text]
  • Severe Osmotic Compression Triggers a Slowdown of Intracellular Signaling, Which Can Be Explained by Molecular Crowding
    Severe osmotic compression triggers a slowdown of intracellular signaling, which can be explained by molecular crowding Agnès Miermonta, François Waharteb, Shiqiong Huc, Megan Nicole McCleand, Samuel Bottania, Sébastien Léone, and Pascal Hersena,c,1 aLaboratoire Matière et Systèmes Complexes, Unité Mixte de Recherche (UMR) 7057, Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot, 75013 Paris, France; bBioImaging Cell and Tissue Core Facility (PICT-IBiSA), UMR 144, CNRS, Institut Curie, 75005 Paris, France; cMechanobiology Institute, National University of Singapore, Singapore 117411; dLewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544; and eInstitut Jacques Monod, CNRS, Université Paris Diderot, 75013 Paris, France Edited by David A. Weitz, Harvard University, Cambridge, MA, and approved February 15, 2013 (received for review September 4, 2012) Regulation of the cellular volume is fundamental for cell survival successive phosphorylation of the HOG mitogen-activated protein and function. Deviations from equilibrium trigger dedicated signaling kinases (MAPKs), culminating in dual phosphorylation of the and transcriptional responses that mediate water homeostasis and Hog1p kinase (4) and leading to the Nmd5p-dependent nuclear volume recovery. Cells are densely packed with proteins, and import of Hog1p, which accumulates in the nucleus (Fig. 1A)and molecular crowding may play an important role in cellular processes. orchestrates a large transcriptional response. Indeed, increasing molecular crowding has been shown to modify One of the main physiological changes that occurs immediately the kinetics of biochemical reactions in vitro; however, the effects of after hyperosmotic stress is an increase in the intracellular protein molecular crowding in living cells are mostly unexplored. Here, we concentrations and the total protein density, thus leading to mo- report that, in yeast, a sudden reduction in cellular volume, induced by lecular crowding.
    [Show full text]