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Jost P, Klein F, Brand B, Wahl V, Wyatt A, Yildiz D, Boehm U, Niemeyer BA, Vaeth M, Alansary D. Acute Downregulation but Not Genetic Ablation of Murine MCU Impairs Suppressive Capacity of Regulatory CD4 T Cells. Int J Mol Sci 2023; 24:ijms24097772. [PMID: 37175478 PMCID: PMC10178810 DOI: 10.3390/ijms24097772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/17/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
By virtue of mitochondrial control of energy production, reactive oxygen species (ROS) generation, and maintenance of Ca2+ homeostasis, mitochondria play an essential role in modulating T cell function. The mitochondrial Ca2+ uniporter (MCU) is the pore-forming unit in the main protein complex mediating mitochondrial Ca2+ uptake. Recently, MCU has been shown to modulate Ca2+ signals at subcellular organellar interfaces, thus fine-tuning NFAT translocation and T cell activation. The mechanisms underlying this modulation and whether MCU has additional T cell subpopulation-specific effects remain elusive. However, mice with germline or tissue-specific ablation of Mcu did not show impaired T cell responses in vitro or in vivo, indicating that 'chronic' loss of MCU can be functionally compensated in lymphocytes. The current work aimed to specifically investigate whether and how MCU influences the suppressive potential of regulatory CD4 T cells (Treg). We show that, in contrast to genetic ablation, acute siRNA-mediated downregulation of Mcu in murine Tregs results in a significant reduction both in mitochondrial Ca2+ uptake and in the suppressive capacity of Tregs, while the ratios of Treg subpopulations and the expression of hallmark transcription factors were not affected. These findings suggest that permanent genetic inactivation of MCU may result in compensatory adaptive mechanisms, masking the effects on the suppressive capacity of Tregs.
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Affiliation(s)
- Priska Jost
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Franziska Klein
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Benjamin Brand
- Würzburg Institute of Systems Immunology, Max Planck Research Group at Julius-Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Vanessa Wahl
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Amanda Wyatt
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Daniela Yildiz
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Ulrich Boehm
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), School of Medicine, Saarland University, 66421 Homburg, Germany
| | | | - Martin Vaeth
- Würzburg Institute of Systems Immunology, Max Planck Research Group at Julius-Maximilians University of Würzburg, 97078 Würzburg, Germany
| | - Dalia Alansary
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
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2
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Rizo T, Gebhardt L, Riedlberger J, Eberhardt E, Fester L, Alansary D, Winkler J, Turan S, Arnold P, Niemeyer BA, Fischer MJM, Winner B. Store-operated calcium entry is reduced in spastin-linked hereditary spastic paraplegia. Brain 2022; 145:3131-3146. [PMID: 36103408 PMCID: PMC9473359 DOI: 10.1093/brain/awac122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/17/2022] [Accepted: 03/22/2022] [Indexed: 01/04/2023] Open
Abstract
Pathogenic variants in SPAST, the gene coding for spastin, are the single most common cause of hereditary spastic paraplegia, a progressive motor neuron disease. Spastin regulates key cellular functions, including microtubule-severing and endoplasmic reticulum-morphogenesis. However, it remains unclear how alterations in these cellular functions due to SPAST pathogenic variants result in motor neuron dysfunction. Since spastin influences both microtubule network and endoplasmic reticulum structure, we hypothesized that spastin is necessary for the regulation of Ca2+ homeostasis via store-operated calcium entry. Here, we show that the lack of spastin enlarges the endoplasmic reticulum and reduces store-operated calcium entry. In addition, elevated levels of different spastin variants induced clustering of STIM1 within the endoplasmic reticulum, altered the transport of STIM1 to the plasma membrane and reduced store-operated calcium entry, which could be rescued by exogenous expression of STIM1. Importantly, store-operated calcium entry was strongly reduced in induced pluripotent stem cell-derived neurons from hereditary spastic paraplegia patients with pathogenic variants in SPAST resulting in spastin haploinsufficiency. These neurons developed axonal swellings in response to lack of spastin. We were able to rescue both store-operated calcium entry and axonal swellings in SPAST patient neurons by restoring spastin levels, using CRISPR/Cas9 to correct the pathogenic variants in SPAST. These findings demonstrate that proper amounts of spastin are a key regulatory component for store-operated calcium entry mediated Ca2+ homeostasis and suggest store-operated calcium entry as a disease relevant mechanism of spastin-linked motor neuron disease.
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Affiliation(s)
- Tania Rizo
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Lisa Gebhardt
- Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Julia Riedlberger
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Esther Eberhardt
- Present address: Department of Anesthesiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Lars Fester
- Institute of Anatomy and Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Dalia Alansary
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Jürgen Winkler
- Department of Molecular Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany,Center of Rare Diseases Erlangen (ZSEER), Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Soeren Turan
- Institute of Biochemistry (Emil-Fischer-Center), Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Philipp Arnold
- Institute of Anatomy, Functional and Clinical Anatomy, Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | | | | | - Beate Winner
- Correspondence to: Beate Winner Department of Stem Cell Biology Friedrich-Alexander University Erlangen-Nürnberg Glückstraße 6 91054 Erlangen, Germany E-mail:
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3
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Hajdu P, Wulff H, Niemeyer BA, Szabó I. Editorial: Ion Channels and Transporters in Ca2+ -Dependent Functions of Lymphocytes. Front Physiol 2022; 13:962110. [PMID: 35874512 PMCID: PMC9301300 DOI: 10.3389/fphys.2022.962110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 06/15/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Peter Hajdu
- Department of Biophysics and Cell Biology, University of Debrecen, Debrecen, Hungary
- Department of Dental Biochemistry, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
- *Correspondence: Peter Hajdu,
| | - Heike Wulff
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, Davis, United States
| | - Barbara A. Niemeyer
- Department of Molecular Biophysics, Faculty of Medicine, Saarland University, Homburg, Germany
| | - Ildikó Szabó
- Department of Biology, Faculty of Sciences, University of Padua, Padua, Italy
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4
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Tandl D, Sponagel T, Alansary D, Fuck S, Smit T, Hehlgans S, Jakob B, Fournier C, Niemeyer BA, Rödel F, Roth B, Moroni A, Thiel G. X-ray irradiation triggers immune response in human T-lymphocytes via store-operated Ca2+ entry and NFAT activation. J Gen Physiol 2022; 154:213138. [PMID: 35416945 PMCID: PMC9011325 DOI: 10.1085/jgp.202112865] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 09/25/2021] [Accepted: 02/11/2022] [Indexed: 12/30/2022] Open
Abstract
Radiation therapy efficiently eliminates cancer cells and reduces tumor growth. To understand collateral agonistic and antagonistic effects of this treatment on the immune system, we examined the impact of x-ray irradiation on human T cells. We find that, in a major population of leukemic Jurkat T cells and peripheral blood mononuclear cells, clinically relevant radiation doses trigger delayed oscillations of the cytosolic Ca2+ concentration. They are generated by store-operated Ca2+ entry (SOCE) following x-ray–induced clustering of Orai1 and STIM1 and formation of a Ca2+ release–activated Ca2+ (CRAC) channel. A consequence of the x-ray–triggered Ca2+ signaling cascade is translocation of the transcription factor nuclear factor of activated T cells (NFAT) from the cytosol into the nucleus, where it elicits the expression of genes required for immune activation. The data imply activation of blood immune cells by ionizing irradiation, with consequences for toxicity and therapeutic effects of radiation therapy.
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Affiliation(s)
- Dominique Tandl
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Tim Sponagel
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Dalia Alansary
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, Homburg/Saar, Germany
| | - Sebastian Fuck
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Timo Smit
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Stephanie Hehlgans
- Department of Radiotherapy and Oncology, Goethe-University, Frankfurt am Main, Germany
| | - Burkhard Jakob
- Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Claudia Fournier
- Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, Homburg/Saar, Germany
| | - Franz Rödel
- Department of Radiotherapy and Oncology, Goethe-University, Frankfurt am Main, Germany
| | - Bastian Roth
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Anna Moroni
- Department of Biosciences and CNR IBF-Mi, Università degli Studi di Milano, Milano, Italy
| | - Gerhard Thiel
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
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5
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Souza Bomfim GH, Niemeyer BA, Lacruz RS, Lis A. On the Connections between TRPM Channels and SOCE. Cells 2022; 11:1190. [PMID: 35406753 PMCID: PMC8997886 DOI: 10.3390/cells11071190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/23/2022] [Accepted: 03/30/2022] [Indexed: 12/02/2022] Open
Abstract
Plasma membrane protein channels provide a passageway for ions to access the intracellular milieu. Rapid entry of calcium ions into cells is controlled mostly by ion channels, while Ca2+-ATPases and Ca2+ exchangers ensure that cytosolic Ca2+ levels ([Ca2+]cyt) are maintained at low (~100 nM) concentrations. Some channels, such as the Ca2+-release-activated Ca2+ (CRAC) channels and voltage-dependent Ca2+ channels (CACNAs), are highly Ca2+-selective, while others, including the Transient Receptor Potential Melastatin (TRPM) family, have broader selectivity and are mostly permeable to monovalent and divalent cations. Activation of CRAC channels involves the coupling between ORAI1-3 channels with the endoplasmic reticulum (ER) located Ca2+ store sensor, Stromal Interaction Molecules 1-2 (STIM1/2), a pathway also termed store-operated Ca2+ entry (SOCE). The TRPM family is formed by 8 members (TRPM1-8) permeable to Mg2+, Ca2+, Zn2+ and Na+ cations, and is activated by multiple stimuli. Recent studies indicated that SOCE and TRPM structure-function are interlinked in some instances, although the molecular details of this interaction are only emerging. Here we review the role of TRPM and SOCE in Ca2+ handling and highlight the available evidence for this interaction.
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Affiliation(s)
- Guilherme H. Souza Bomfim
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Barbara A. Niemeyer
- Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany;
| | - Rodrigo S. Lacruz
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Annette Lis
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany
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Knapp ML, Alansary D, Poth V, Förderer K, Sommer F, Zimmer D, Schwarz Y, Künzel N, Kless A, Machaca K, Helms V, Mühlhaus T, Schroda M, Lis A, Niemeyer BA. A longer isoform of Stim1 is a negative SOCE regulator but increases cAMP-modulated NFAT signaling. EMBO Rep 2021; 23:e53135. [PMID: 34942054 PMCID: PMC8892257 DOI: 10.15252/embr.202153135] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 11/23/2021] [Accepted: 12/07/2021] [Indexed: 11/23/2022] Open
Abstract
Alternative splicing is a potent modifier of protein function. Stromal interaction molecule 1 (Stim1) is the essential activator of store‐operated Ca2+ entry (SOCE) triggering activation of transcription factors. Here, we characterize Stim1A, a splice variant with an additional 31 amino acid domain inserted in frame within its cytosolic domain. Prominent expression of exon A is found in astrocytes, heart, kidney, and testes. Full‐length Stim1A functions as a dominant‐negative regulator of SOCE and ICRAC, facilitating sequence‐specific fast calcium‐dependent inactivation and destabilizing gating of Orai channels. Downregulation or absence of native Stim1A results in increased SOCE. Despite reducing SOCE, Stim1A leads to increased NFAT translocation. Differential proteomics revealed an interference of Stim1A with the cAMP‐SOCE crosstalk by altered modulation of phosphodiesterase 8 (PDE8), resulting in reduced cAMP degradation and increased PIP5K activity, facilitating NFAT activation. Our study uncovers a hitherto unknown mechanism regulating NFAT activation and indicates that cell‐type‐specific splicing of Stim1 is a potent means to regulate the NFAT signalosome and cAMP‐SOCE crosstalk.
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Affiliation(s)
- Mona L Knapp
- Molecular Biophysics, Saarland University, Homburg, Germany
| | - Dalia Alansary
- Molecular Biophysics, Saarland University, Homburg, Germany
| | - Vanessa Poth
- Molecular Biophysics, Saarland University, Homburg, Germany
| | | | - Frederik Sommer
- Molecular Biotechnology and Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - David Zimmer
- Computational Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - Yvonne Schwarz
- Molecular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Nicolas Künzel
- Center for Bioinformatics, Saarland University, Saarbruecken, Germany
| | - Achim Kless
- Grünenthal Innovation, Drug Discovery Technologies, Grünenthal GmbH, Aachen, Germany
| | | | - Volkhard Helms
- Center for Bioinformatics, Saarland University, Saarbruecken, Germany
| | - Timo Mühlhaus
- Computational Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - Michael Schroda
- Molecular Biotechnology and Systems Biology, TU Kaiserslautern, Kaiserslautern, Germany
| | - Annette Lis
- Biophysics, Saarland University, Homburg, Germany
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7
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Pick T, Beck A, Gamayun I, Schwarz Y, Schirra C, Jung M, Krause E, Niemeyer BA, Zimmermann R, Lang S, Anken EV, Cavalié A. Remodelling of Ca 2+ homeostasis is linked to enlarged endoplasmic reticulum in secretory cells. Cell Calcium 2021; 99:102473. [PMID: 34560367 DOI: 10.1016/j.ceca.2021.102473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 08/27/2021] [Accepted: 09/08/2021] [Indexed: 11/30/2022]
Abstract
The endoplasmic reticulum (ER) is extensively remodelled during the development of professional secretory cells to cope with high protein production. Since ER is the principal Ca2+ store in the cell, we characterised the Ca2+ homeostasis in NALM-6 and RPMI 8226 cells, which are commonly used as human pre-B and antibody secreting plasma cell models, respectively. Expression levels of Sec61 translocons and the corresponding Sec61-mediated Ca2+ leak from ER, Ca2+ storage capacity and store-operated Ca2+ entry were significantly enlarged in the secretory RPMI 8226 cell line. Using an immunoglobulin M heavy chain producing HeLa cell model, we found that the enlarged Ca2+ storage capacity and Ca2+ leak from ER are linked to ER expansion. Our data delineates a developmental remodelling of Ca2+ homeostasis in professional secretory cells in which a high Sec61-mediated Ca2+ leak and, thus, a high Ca2+ turnover in the ER is backed up by enhanced store-operated Ca2+ entry.
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Affiliation(s)
- Tillman Pick
- Experimental and Clinical Pharmacology and Toxicology, Pre-clinical Center for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany.
| | - Andreas Beck
- Experimental and Clinical Pharmacology and Toxicology, Pre-clinical Center for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Igor Gamayun
- Experimental and Clinical Pharmacology and Toxicology, Pre-clinical Center for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Yvonne Schwarz
- Molecular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, 66421 Homburg, Germany
| | - Claudia Schirra
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, 66421 Homburg, Germany
| | - Martin Jung
- Medical Biochemistry and Molecular Biology, Pre-clinical Centre for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Elmar Krause
- Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, 66421 Homburg, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, 66421 Homburg, Germany
| | - Richard Zimmermann
- Medical Biochemistry and Molecular Biology, Pre-clinical Centre for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Sven Lang
- Medical Biochemistry and Molecular Biology, Pre-clinical Centre for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Eelco van Anken
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute and Università Vita-Salute San Raffaele, Milan, Italy
| | - Adolfo Cavalié
- Experimental and Clinical Pharmacology and Toxicology, Pre-clinical Center for Molecular Signalling (PZMS), Saarland University, 66421 Homburg, Germany.
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8
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Schunk SJ, Triem S, Schmit D, Zewinger S, Sarakpi T, Becker E, Hütter G, Wrublewsky S, Küting F, Hohl M, Alansary D, Prates Roma L, Lipp P, Möllmann J, Lehrke M, Laschke MW, Menger MD, Kramann R, Boor P, Jahnen-Dechent W, März W, Böhm M, Laufs U, Niemeyer BA, Fliser D, Ampofo E, Speer T. Interleukin-1α Is a Central Regulator of Leukocyte-Endothelial Adhesion in Myocardial Infarction and in Chronic Kidney Disease. Circulation 2021; 144:893-908. [PMID: 34192892 DOI: 10.1161/circulationaha.121.053547] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Cardiovascular diseases and chronic kidney disease (CKD) are highly prevalent, aggravate each other, and account for substantial mortality. Both conditions are characterized by activation of the innate immune system. The alarmin interleukin-1α (IL-1α) is expressed in a variety of cell types promoting (sterile) systemic inflammation. The aim of the present study was to examine the role of IL-1α in mediating inflammation in the setting of acute myocardial infarction (AMI) and CKD. METHODS We assessed the expression of IL-1α on the surface of monocytes from patients with AMI and patients with CKD and determined its association with atherosclerotic cardiovascular disease events during follow-up in an explorative clinical study. Furthermore, we assessed the inflammatory effects of IL-1α in several organ injury models in Il1a-/- and Il1b-/- mice and investigated the underlying mechanisms in vitro in monocytes and endothelial cells. RESULTS IL-1α is strongly expressed on the surface of monocytes from patients with AMI and CKD compared with healthy controls. Higher IL-1α surface expression on monocytes from patients with AMI and CKD was associated with a higher risk for atherosclerotic cardiovascular disease events, which underlines the clinical relevance of IL-1α. In mice, IL-1α, but not IL-1β, mediates leukocyte-endothelial adhesion as determined by intravital microscopy. IL-1α promotes accumulation of macrophages and neutrophils in inflamed tissue in vivo. Furthermore, IL-1α on monocytes stimulates their homing at sites of vascular injury. A variety of stimuli such as free fatty acids or oxalate crystals induce IL-1α surface expression and release by monocytes, which then mediates their adhesion to the endothelium via IL-1 receptor-1. IL-1α also promotes expression of the VCAM-1 (vascular cell adhesion molecule-1) on endothelial cells, thereby fostering the adhesion of circulating leukocytes. IL-1α induces inflammatory injury after experimental AMI, and abrogation of IL-1α prevents the development of CKD in oxalate or adenine-fed mice. CONCLUSIONS IL-1α represents a key mediator of leukocyte-endothelial adhesion and inflammation in AMI and CKD. Inhibition of IL-1α may serve as a novel anti-inflammatory treatment strategy.
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Affiliation(s)
- Stefan J Schunk
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Sarah Triem
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany.,Translational Cardiorenal Medicine (S.T., E.B., G.H., F.K., T. Speer), Saarland University, Homburg/Saar, Germany
| | - David Schmit
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Stephen Zewinger
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Tamim Sarakpi
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Ellen Becker
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany.,Translational Cardiorenal Medicine (S.T., E.B., G.H., F.K., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Gregor Hütter
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany.,Translational Cardiorenal Medicine (S.T., E.B., G.H., F.K., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Selina Wrublewsky
- Institute of Clinical and Experimental Surgery (S.W., M.W.L., M.D.M., E.A.), Saarland University, Homburg/Saar, Germany
| | - Fabienne Küting
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany.,Translational Cardiorenal Medicine (S.T., E.B., G.H., F.K., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Mathias Hohl
- Department of Internal Medicine III, Cardiology, Angiology, and Intensity Care Medicine (M.H., M.B.), Saarland University, Homburg/Saar, Germany
| | - Dalia Alansary
- Institute of Biophysics, Center of Integrative Physiology and Molecular Medicine (CIPMM) (D.A., L.P.R., B.A.N.), Saarland University, Homburg/Saar, Germany
| | - Leticia Prates Roma
- Institute of Biophysics, Center of Integrative Physiology and Molecular Medicine (CIPMM) (D.A., L.P.R., B.A.N.), Saarland University, Homburg/Saar, Germany
| | - Peter Lipp
- Institute of Cell Biology (P.L.), Saarland University, Homburg/Saar, Germany
| | - Julia Möllmann
- Department of Cardiology (J.M., M.L.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany
| | - Michael Lehrke
- Department of Cardiology (J.M., M.L.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany
| | - Matthias W Laschke
- Institute of Clinical and Experimental Surgery (S.W., M.W.L., M.D.M., E.A.), Saarland University, Homburg/Saar, Germany
| | - Michael D Menger
- Institute of Clinical and Experimental Surgery (S.W., M.W.L., M.D.M., E.A.), Saarland University, Homburg/Saar, Germany
| | - Rafael Kramann
- Department of Nephrology (R.K.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany.,Institute of Experimental Medicine and Systems Biology (R.K.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany
| | - Peter Boor
- Institute of Pathology (P.B.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany
| | - Willi Jahnen-Dechent
- Biointerface Laboratory (W.J.-D.), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University Hospital, Germany
| | - Winfried März
- Vth Department of Medicine, University Heidelberg, Mannheim Medical Faculty, Mannheim, Germany (W.M.).,Clinical Institute of Medical and Laboratory Diagnostics, Medical University Graz, Austria (W.M.).,Synlab Academy, Synlab Holding, Mannheim, Germany (W.M.)
| | - Michael Böhm
- Department of Internal Medicine III, Cardiology, Angiology, and Intensity Care Medicine (M.H., M.B.), Saarland University, Homburg/Saar, Germany
| | - Ulrich Laufs
- Department of Cardiology, University Hospital Leipzig, Germany (U.L.)
| | - Barbara A Niemeyer
- Institute of Biophysics, Center of Integrative Physiology and Molecular Medicine (CIPMM) (D.A., L.P.R., B.A.N.), Saarland University, Homburg/Saar, Germany
| | - Danilo Fliser
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany
| | - Emmanuel Ampofo
- Institute of Clinical and Experimental Surgery (S.W., M.W.L., M.D.M., E.A.), Saarland University, Homburg/Saar, Germany
| | - Thimoteus Speer
- Department of Internal Medicine IV, Nephrology and Hypertension (S.J.S., S.T., D.S., S.Z., T. Sarakpi, E.B., G.H., F.K., D.F., T. Speer), Saarland University, Homburg/Saar, Germany.,Translational Cardiorenal Medicine (S.T., E.B., G.H., F.K., T. Speer), Saarland University, Homburg/Saar, Germany
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9
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Merino-Wong M, Niemeyer BA, Alansary D. Plasma Membrane Calcium ATPase Regulates Stoichiometry of CD4 + T-Cell Compartments. Front Immunol 2021; 12:687242. [PMID: 34093590 PMCID: PMC8175910 DOI: 10.3389/fimmu.2021.687242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
Immune responses involve mobilization of T cells within naïve and memory compartments. Tightly regulated Ca2+ levels are essential for balanced immune outcomes. How Ca2+ contributes to regulating compartment stoichiometry is unknown. Here, we show that plasma membrane Ca2+ ATPase 4 (PMCA4) is differentially expressed in human CD4+ T compartments yielding distinct store operated Ca2+ entry (SOCE) profiles. Modulation of PMCA4 yielded a more prominent increase of SOCE in memory than in naïve CD4+ T cell. Interestingly, downregulation of PMCA4 reduced the effector compartment fraction and led to accumulation of cells in the naïve compartment. In silico analysis and chromatin immunoprecipitation point towards Ying Yang 1 (YY1) as a transcription factor regulating PMCA4 expression. Analyses of PMCA and YY1 expression patterns following activation and of PMCA promoter activity following downregulation of YY1 highlight repressive role of YY1 on PMCA expression. Our findings show that PMCA4 adapts Ca2+ levels to cellular requirements during effector and quiescent phases and thereby represent a potential target to intervene with the outcome of the immune response.
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Affiliation(s)
| | | | - Dalia Alansary
- Molecular Biophysics, Saarland University, Homburg, Germany
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10
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Schunk SJ, Kleber ME, März W, Pang S, Zewinger S, Triem S, Ege P, Reichert MC, Krawczyk M, Weber SN, Jaumann I, Schmit D, Sarakpi T, Wagenpfeil S, Kramann R, Boerwinkle E, Ballantyne CM, Grove ML, Tragante V, Pilbrow AP, Richards AM, Cameron VA, Doughty RN, Dubé MP, Tardif JC, Feroz-Zada Y, Sun M, Liu C, Ko YA, Quyyumi AA, Hartiala JA, Tang WHW, Hazen SL, Allayee H, McDonough CW, Gong Y, Cooper-DeHoff RM, Johnson JA, Scholz M, Teren A, Burkhardt R, Martinsson A, Smith JG, Wallentin L, James SK, Eriksson N, White H, Held C, Waterworth D, Trompet S, Jukema JW, Ford I, Stott DJ, Sattar N, Cresci S, Spertus JA, Campbell H, Tierling S, Walter J, Ampofo E, Niemeyer BA, Lipp P, Schunkert H, Böhm M, Koenig W, Fliser D, Laufs U, Speer T. Genetically determined NLRP3 inflammasome activation associates with systemic inflammation and cardiovascular mortality. Eur Heart J 2021; 42:1742-1756. [PMID: 33748830 PMCID: PMC8244638 DOI: 10.1093/eurheartj/ehab107] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/19/2020] [Accepted: 02/09/2021] [Indexed: 12/12/2022] Open
Abstract
AIMS Inflammation plays an important role in cardiovascular disease (CVD) development. The NOD-like receptor protein-3 (NLRP3) inflammasome contributes to the development of atherosclerosis in animal models. Components of the NLRP3 inflammasome pathway such as interleukin-1β can therapeutically be targeted. Associations of genetically determined inflammasome-mediated systemic inflammation with CVD and mortality in humans are unknown. METHODS AND RESULTS We explored the association of genetic NLRP3 variants with prevalent CVD and cardiovascular mortality in 538 167 subjects on the individual participant level in an explorative gene-centric approach without performing multiple testing. Functional relevance of single-nucleotide polymorphisms on NLRP3 inflammasome activation has been evaluated in monocyte-enriched peripheral blood mononuclear cells (PBMCs). Genetic analyses identified the highly prevalent (minor allele frequency 39.9%) intronic NLRP3 variant rs10754555 to affect NLRP3 gene expression. rs10754555 carriers showed significantly higher C-reactive protein and serum amyloid A plasma levels. Carriers of the G allele showed higher NLRP3 inflammasome activation in isolated human PBMCs. In carriers of the rs10754555 variant, the prevalence of coronary artery disease was significantly higher as compared to non-carriers with a significant interaction between rs10754555 and age. Importantly, rs10754555 carriers had significantly higher risk for cardiovascular mortality during follow-up. Inflammasome inducers (e.g. urate, triglycerides, apolipoprotein C3) modulated the association between rs10754555 and mortality. CONCLUSION The NLRP3 intronic variant rs10754555 is associated with increased systemic inflammation, inflammasome activation, prevalent coronary artery disease, and mortality. This study provides evidence for a substantial role of genetically driven systemic inflammation in CVD and highlights the NLRP3 inflammasome as a therapeutic target.
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Affiliation(s)
- Stefan J Schunk
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Marcus E Kleber
- Vth Department of Medicine, University Heidelberg, Mannheim Medical Faculty, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
- SYNLAB MVZ Humangenetik Mannheim, Harrlachweg 1, 68163 Mannheim, Germany
| | - Winfried März
- Vth Department of Medicine, University Heidelberg, Mannheim Medical Faculty, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
- Clinical Institute of Medical and Laboratory Diagnostics, Medical University Graz, Auenbruggerpl. 2, 8036 Graz, Austria
- Synlab Academy, Synlab Holding GmbH, Harrlachweg 1, 68163 Mannheim, Germany
| | - Shichao Pang
- Kardiologie, Deutsches Herzzentrum München, Technische Universität München, Lazarettstraße 36, 80636 Munich, Germany
| | - Stephen Zewinger
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Sarah Triem
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Philipp Ege
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Matthias C Reichert
- Department of Medicine II, Saarland University Medical Center, Kirrberger Straße, 66424 Homburg, Germany
| | - Marcin Krawczyk
- Department of Medicine II, Saarland University Medical Center, Kirrberger Straße, 66424 Homburg, Germany
- Laboratory of Metabolic Liver Diseases, Centre for Preclinical Research, Department of General, Transplant and Liver Surgery, Medical University of Warsaw, ul. Banacha 1B, CePT, 02-097 Warsaw, Poland
| | - Susanne N Weber
- Department of Medicine II, Saarland University Medical Center, Kirrberger Straße, 66424 Homburg, Germany
| | - Isabella Jaumann
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - David Schmit
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Tamim Sarakpi
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Stefan Wagenpfeil
- Institute of Medical Biometry, Epidemiology & Medical Informatics, Saarland University Campus Homburg/Saar, Kirrberger Straße, 66424 Homburg/Saar, Germany
| | - Rafael Kramann
- Division of Nephrology and Clinical Immunology, RWTH Aachen University, Pauwelsstrasse 30 52074 Aachen, Germany
- Institute of Experimental Medicine and Systems Biology, RWTH, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Eric Boerwinkle
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, 1200 Pressler Street, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, BCM226, Houston, TX 77030, USA
| | - Christie M Ballantyne
- Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
- Center of Cardiovascular Disease Prevention, Methodist DeBakey Heart and Vascular Center, 6565 Fannin St, Houston, TX 77030, USA
| | - Megan L Grove
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, 1200 Pressler Street, Houston, TX 77030, USA
| | - Vinicius Tragante
- Department of Cardiology, Heart and Lungs Division, UMC Utrecht, Heidelberglaan 100 3584 CX Utrecht, Netherlands
| | - Anna P Pilbrow
- The Christchurch Heart Institute, University of Otago Christchurch, 2 Riccarton Avenue, Christchurch Central City, Christchurch 8011, New Zealand
| | - A Mark Richards
- The Christchurch Heart Institute, University of Otago Christchurch, 2 Riccarton Avenue, Christchurch Central City, Christchurch 8011, New Zealand
| | - Vicky A Cameron
- The Christchurch Heart Institute, University of Otago Christchurch, 2 Riccarton Avenue, Christchurch Central City, Christchurch 8011, New Zealand
| | - Robert N Doughty
- Heart Health Research Group, University of Auckland, Level 2 / 22-30 Park Ave, Grafton, Auckland, New Zealand
| | - Marie-Pierre Dubé
- Montreal Heart Institute, 5000 Rue Bélanger, Montreal QC H1T 1C8, Canada
- Faculty of Medicine, Université der Montréal, Pavillon Roger-Gaudry, 2900 Edouard Montpetit Blvd, Montreal, Quebec H3T 1J4, Canada
| | - Jean-Claude Tardif
- Montreal Heart Institute, 5000 Rue Bélanger, Montreal QC H1T 1C8, Canada
- Faculty of Medicine, Université der Montréal, Pavillon Roger-Gaudry, 2900 Edouard Montpetit Blvd, Montreal, Quebec H3T 1J4, Canada
| | | | - Maxine Sun
- Faculty of Medicine, Université der Montréal, Pavillon Roger-Gaudry, 2900 Edouard Montpetit Blvd, Montreal, Quebec H3T 1J4, Canada
| | - Chang Liu
- Emory Clinical Cardiovascular Research Institute, Division of Cardiology, Emory University School of Medicine, 1462 Clifton Road NE, Atlanta, GA 30322, USA
| | - Yi-An Ko
- Department of Biostatistics and Bioinformatics, Rollins School of Public Healthy, Emory University, 1518 Clifton Road NE, Atlanta, GA 30322, USA
| | - Arshed A Quyyumi
- Emory Clinical Cardiovascular Research Institute, Division of Cardiology, Emory University School of Medicine, 1462 Clifton Road NE, Atlanta, GA 30322, USA
| | - Jaana A Hartiala
- Department of Preventive Medicine, University of Southern California, Keck School of Medicine, 2001 N. Soto St. Los Angeles, CA 90033, USA
| | - W H Wilson Tang
- Department of Cardiovascular Medicine, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195, USA
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Ave, NB 21, Cleveland, OH 44195, USA
| | - Stanley L Hazen
- Department of Cardiovascular Medicine, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195, USA
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Ave, NB 21, Cleveland, OH 44195, USA
| | - Hooman Allayee
- Department of Preventive Medicine, University of Southern California, Keck School of Medicine, 2001 N. Soto St. Los Angeles, CA 90033, USA
| | - Caitrin W McDonough
- Department of Pharmacotherapy and Translational Research, University of Florida, College of Pharmacy, 1225 Center Drive, HPNP Building, Gainesville, FL 32610-0486, USA
| | - Yan Gong
- Department of Pharmacotherapy and Translational Research, University of Florida, College of Pharmacy, 1225 Center Drive, HPNP Building, Gainesville, FL 32610-0486, USA
| | - Rhonda M Cooper-DeHoff
- Department of Pharmacotherapy and Translational Research, University of Florida, College of Pharmacy, 1225 Center Drive, HPNP Building, Gainesville, FL 32610-0486, USA
- Division of Cardiovascular Medicine, Department of Medicine, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA
| | - Julie A Johnson
- Department of Pharmacotherapy and Translational Research, University of Florida, College of Pharmacy, 1225 Center Drive, HPNP Building, Gainesville, FL 32610-0486, USA
- Division of Cardiovascular Medicine, Department of Medicine, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA
| | - Markus Scholz
- Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
- LIFE Research Center for Civilization Diseases, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Andrej Teren
- LIFE Research Center for Civilization Diseases, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
- Heart Center Leipzig, Strümpellstraße 39, 04289 Leipzig, Germany
| | - Ralph Burkhardt
- LIFE Research Center for Civilization Diseases, University of Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg,Germany
| | - Andreas Martinsson
- Department of Cardiology, Sahlgrenska University Hospital, Blå stråket 5, 413 45 Göteborg, Sweden
| | - J Gustav Smith
- Department of Cardiology, Clinical Sciences, Lund University and Skane University Hospital, BMC F12, 221 84 Lund, Sweden
| | - Lars Wallentin
- Department of Medical Sciences, Cardiology, Uppsala University, Akademiska sjukhuset Entrance 40, 751 85 Uppsala, Sweden
- Uppsala Clinical Research Center, Uppsala University, Dag Hammarskjölds Väg 38, 751 85 Uppsala, Sweden
| | - Stefan K James
- Department of Medical Sciences, Cardiology, Uppsala University, Akademiska sjukhuset Entrance 40, 751 85 Uppsala, Sweden
- Uppsala Clinical Research Center, Uppsala University, Dag Hammarskjölds Väg 38, 751 85 Uppsala, Sweden
| | - Niclas Eriksson
- Department of Medical Sciences, Cardiology, Uppsala University, Akademiska sjukhuset Entrance 40, 751 85 Uppsala, Sweden
- Uppsala Clinical Research Center, Uppsala University, Dag Hammarskjölds Väg 38, 751 85 Uppsala, Sweden
| | - Harvey White
- Green Lane Cardiovascular Service, Auckland City Hospital, 2 Park Road, Grafton, Auckland 1023, New Zealand
| | - Claes Held
- Department of Medical Sciences, Cardiology, Uppsala University, Akademiska sjukhuset Entrance 40, 751 85 Uppsala, Sweden
- Uppsala Clinical Research Center, Uppsala University, Dag Hammarskjölds Väg 38, 751 85 Uppsala, Sweden
| | - Dawn Waterworth
- Genetics, GlaxoSmithKline, 709 Swedeland Rd, King of Prussia, PA 19406, USA
| | - Stella Trompet
- Department of Internal Medicine, Section of Gerontology and Geriatrics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - J Wouter Jukema
- Department of Cardiology, Leiden University Medical Cernter, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
- Netherlands Heart Institute, Moreelsepark 1, 3511 EP Utrecht, The Netherlands
| | - Ian Ford
- Robertson Centre for Biostatistics, University of Glasgow, Boyd Orr Building University Avenue, Glasgow G12 8QQ, UK
| | - David J Stott
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Naveed Sattar
- BHF Glasgow Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA UK
| | - Sharon Cresci
- Washington University School of Medicine, 2300 I St NW, Washington, DC 20052, USA
- Department of Medicine & Genetics, Campus Box 8232, 4515 McKinley Ave., St. Louis, MO 63110, USA
| | - John A Spertus
- Saint Luke's Mid America Heart Institute and University of Missouri-Kansas City, 4401 Wornall Rd, Kansas City, MO 64111, USA
| | - Hannah Campbell
- Washington University School of Medicine, 2300 I St NW, Washington, DC 20052, USA
- Department of Medicine & Genetics, Campus Box 8232, 4515 McKinley Ave., St. Louis, MO 63110, USA
| | - Sascha Tierling
- Faculty of Natural Sciences and Technology, Department of Genetics/Epigenetics, Saarland University, Postfach 151150, 66041 Saarbrücken, Germany
| | - Jörn Walter
- Faculty of Natural Sciences and Technology, Department of Genetics/Epigenetics, Saarland University, Postfach 151150, 66041 Saarbrücken, Germany
| | - Emmanuel Ampofo
- Institute of Clinical & Experimental Surgery, Saarland University, Kirrberger Straße, 66424 Homburg/Saar, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, CIPMM, Saarland University, Kirrberger Straße, 66424 Homburg/Saar, Germany
| | - Peter Lipp
- Center for Molecular Signaling (PZMS), Institute for Molecular Cell Biology, Research Center for Molecular Imaging and Screening, Medical Faculty, Saarland University, Kirrberger Straße, 66424 Homburg, Germany
| | - Heribert Schunkert
- Kardiologie, Deutsches Herzzentrum München, Technische Universität München, Lazarettstraße 36, 80636 Munich, Germany
- Partner Site Munich Heart Alliance, German Centre of Cardiovascular Research (DZHK), Ismaninger Straße 22, 81675 Munich, Germany
| | - Michael Böhm
- Department of Internal Medicine III, Cardiology, Angiology, and Intensive Care Medicine, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Wolfgang Koenig
- Kardiologie, Deutsches Herzzentrum München, Technische Universität München, Lazarettstraße 36, 80636 Munich, Germany
- Partner Site Munich Heart Alliance, German Centre of Cardiovascular Research (DZHK), Ismaninger Straße 22, 81675 Munich, Germany
- Institute of Epidemiology and Medical Biometry, University of Ulm, Helmholtzstr. 22, 89081 Ulm, Germany
| | - Danilo Fliser
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
| | - Ulrich Laufs
- Department of Cardiology, University Medical Center Leipzig, Liebigstraße 20, Leipzig, Germany
| | - Thimoteus Speer
- Department of Internal Medicine IV, Nephrology and Hypertension, Saarland University Hospital, Kirrberger Strasse, Building 41, 66424 Homburg/Saar, Germany
- Translational Cardio-Renal Medicine, Saarland University, Kirrberger Straße, 66424 Homburg/Saar, Germany
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11
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Ramesh G, Jarzembowski L, Schwarz Y, Poth V, Konrad M, Knapp ML, Schwär G, Lauer AA, Grimm MOW, Alansary D, Bruns D, Niemeyer BA. A short isoform of STIM1 confers frequency-dependent synaptic enhancement. Cell Rep 2021; 34:108844. [PMID: 33730587 DOI: 10.1016/j.celrep.2021.108844] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 12/16/2020] [Accepted: 02/17/2021] [Indexed: 12/25/2022] Open
Abstract
Store-operated Ca2+-entry (SOCE) regulates basal and receptor-triggered Ca2+ signaling with STIM proteins sensing the endoplasmic reticulum (ER) Ca2+ content and triggering Ca2+ entry by gating Orai channels. Although crucial for immune cells, STIM1's role in neuronal Ca2+ homeostasis is controversial. Here, we characterize a splice variant, STIM1B, which shows exclusive neuronal expression and protein content surpassing conventional STIM1 in cerebellum and of significant abundance in other brain regions. STIM1B expression results in a truncated protein with slower kinetics of ER-plasma membrane (PM) cluster formation and ICRAC, as well as reduced inactivation. In primary wild-type neurons, STIM1B is targeted by its spliced-in domain B to presynaptic sites where it converts classic synaptic depression into Ca2+- and Orai-dependent short-term synaptic enhancement (STE) at high-frequency stimulation (HFS). In conjunction with altered STIM1 splicing in human Alzheimer disease, our findings highlight STIM1 splicing as an important regulator of neuronal calcium homeostasis and of synaptic plasticity.
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Affiliation(s)
- Girish Ramesh
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | | | - Yvonne Schwarz
- Molecular Neurophysiology, Saarland University, 66421 Homburg, Germany
| | - Vanessa Poth
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Maik Konrad
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Mona L Knapp
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Gertrud Schwär
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), Bld. 48, Saarland University, 66421 Homburg, Germany
| | - Anna A Lauer
- Experimental Neurology, Saarland University, 66421 Homburg, Germany
| | - Marcus O W Grimm
- Experimental Neurology, Saarland University, 66421 Homburg, Germany
| | - Dalia Alansary
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Dieter Bruns
- Molecular Neurophysiology, Saarland University, 66421 Homburg, Germany
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12
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13
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Zou H, Yang W, Schwär G, Zhao R, Alansary D, Yin D, Schwarz EC, Niemeyer BA, Qu B. High glucose distinctively regulates Ca 2+ influx in cytotoxic T lymphocytes upon target recognition and thapsigargin stimulation. Eur J Immunol 2020; 50:2095-2098. [PMID: 32697355 DOI: 10.1002/eji.202048577] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 06/11/2020] [Accepted: 07/21/2020] [Indexed: 11/08/2022]
Abstract
In CTLs: High glucose-culture enhances thapsigargin-induced SOCE but decreases target recognition-induced Ca2+ influx. High glucose-culture regulates expression of ORAIs and STIMs without affecting glucose uptake. More high glucose-cultured CTLs are prone to necrosis after execution of killing.
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Affiliation(s)
- Huajiao Zou
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China.,Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Wenjuan Yang
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Gertrud Schwär
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Renping Zhao
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Dalia Alansary
- Molecular Biophysics, CIPMM, School of Medicine, Saarland University, Homburg, Germany
| | - Deling Yin
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China.,Department of Internal Medicine, College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - Eva C Schwarz
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, CIPMM, School of Medicine, Saarland University, Homburg, Germany
| | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg, Germany.,INM-Leibniz Institute for New Materials, Saarbrücken, Germany
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14
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Alansary D, Peckys DB, Niemeyer BA, de Jonge N. Detecting single ORAI1 proteins within the plasma membrane reveals higher-order channel complexes. J Cell Sci 2020; 133:jcs.240358. [PMID: 31822631 DOI: 10.1242/jcs.240358] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/02/2019] [Indexed: 12/22/2022] Open
Abstract
ORAI1 proteins form highly selective Ca2+ channels in the plasma membrane. Crystallographic data point towards a hexameric stoichiometry of ORAI1 channels, whereas optical methods postulated ORAI1 channels to reside as dimers at rest, and other data suggests that they have a tetrameric configuration. Here, liquid-phase scanning transmission electron microscopy (STEM) and quantum dot (QD) labeling was utilized to study the conformation of ORAI1 proteins at rest. To address the question of whether ORAI1 was present as a dimer, experiments were designed using single ORAI1 monomers and covalently linked ORAI1 dimers with either one or two label-binding positions. The microscopic data was statistically analyzed via the pair correlation function. Label pairs were found in all cases, even for concatenated dimers with one label-binding position, which is only possible if a significant fraction of ORAI1 was assembled in larger order oligomers than dimers, binding at least two QDs. This interpretation of the data was consistent with Blue Native PAGE analysis showing that ORAI1 is mainly present as a complex of an apparent molecular mass larger than that calculated for a dimer.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Diana B Peckys
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, University of Saarland, Center for Integrative Physiology and Molecular Medicine, 66421 Homburg/Saar, Germany
| | - Niels de Jonge
- INM - Leibniz Institute for New Materials, 66123 Saarbrücken, Germany .,Department of Physics, University of Saarland, 66123 Saarbrücken, Germany
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15
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Zhang X, Gibhardt CS, Will T, Stanisz H, Körbel C, Mitkovski M, Stejerean I, Cappello S, Pacheu‐Grau D, Dudek J, Tahbaz N, Mina L, Simmen T, Laschke MW, Menger MD, Schön MP, Helms V, Niemeyer BA, Rehling P, Vultur A, Bogeski I. Redox signals at the ER-mitochondria interface control melanoma progression. EMBO J 2019; 38:e100871. [PMID: 31304984 PMCID: PMC6669928 DOI: 10.15252/embj.2018100871] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 05/21/2019] [Accepted: 05/23/2019] [Indexed: 12/20/2022] Open
Abstract
Reactive oxygen species (ROS) are emerging as important regulators of cancer growth and metastatic spread. However, how cells integrate redox signals to affect cancer progression is not fully understood. Mitochondria are cellular redox hubs, which are highly regulated by interactions with neighboring organelles. Here, we investigated how ROS at the endoplasmic reticulum (ER)-mitochondria interface are generated and translated to affect melanoma outcome. We show that TMX1 and TMX3 oxidoreductases, which promote ER-mitochondria communication, are upregulated in melanoma cells and patient samples. TMX knockdown altered mitochondrial organization, enhanced bioenergetics, and elevated mitochondrial- and NOX4-derived ROS. The TMX-knockdown-induced oxidative stress suppressed melanoma proliferation, migration, and xenograft tumor growth by inhibiting NFAT1. Furthermore, we identified NFAT1-positive and NFAT1-negative melanoma subgroups, wherein NFAT1 expression correlates with melanoma stage and metastatic potential. Integrative bioinformatics revealed that genes coding for mitochondrial- and redox-related proteins are under NFAT1 control and indicated that TMX1, TMX3, and NFAT1 are associated with poor disease outcome. Our study unravels a novel redox-controlled ER-mitochondria-NFAT1 signaling loop that regulates melanoma pathobiology and provides biomarkers indicative of aggressive disease.
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Affiliation(s)
- Xin Zhang
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
- BiophysicsCIPMMSaarland UniversityHomburgGermany
| | - Christine S Gibhardt
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Thorsten Will
- Center for BioinformaticsSaarland UniversitySaarbrückenGermany
| | - Hedwig Stanisz
- Department of Dermatology, Venereology and AllergologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Christina Körbel
- Institute for Clinical and Experimental SurgerySaarland UniversityHomburgGermany
| | - Miso Mitkovski
- Light Microscopy FacilityMax Planck Institute for Experimental MedicineGöttingenGermany
| | - Ioana Stejerean
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Sabrina Cappello
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - David Pacheu‐Grau
- Department of Cellular BiochemistryUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Jan Dudek
- Department of Cellular BiochemistryUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Nasser Tahbaz
- Department of Cell BiologyUniversity of AlbertaEdmontonABCanada
| | - Lucas Mina
- Department of Cell BiologyUniversity of AlbertaEdmontonABCanada
| | - Thomas Simmen
- Department of Cell BiologyUniversity of AlbertaEdmontonABCanada
| | - Matthias W Laschke
- Institute for Clinical and Experimental SurgerySaarland UniversityHomburgGermany
| | - Michael D Menger
- Institute for Clinical and Experimental SurgerySaarland UniversityHomburgGermany
| | - Michael P Schön
- Department of Dermatology, Venereology and AllergologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Volkhard Helms
- Center for BioinformaticsSaarland UniversitySaarbrückenGermany
| | | | - Peter Rehling
- Department of Cellular BiochemistryUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
- Max Planck Institute for Biophysical ChemistryGöttingenGermany
| | - Adina Vultur
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
| | - Ivan Bogeski
- Molecular PhysiologyInstitute of Cardiovascular PhysiologyUniversity Medical CenterGeorg‐August‐UniversityGöttingenGermany
- BiophysicsCIPMMSaarland UniversityHomburgGermany
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16
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Lang I, Jung M, Niemeyer BA, Ruth P, Engel J. Expression of the LRRC52 γ subunit (γ2) may provide Ca 2+-independent activation of BK currents in mouse inner hair cells. FASEB J 2019; 33:11721-11734. [PMID: 31348683 DOI: 10.1096/fj.201900701rr] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Mammalian inner hair cells (IHCs) transduce sound into depolarization and transmitter release. Big conductance and voltage- and Ca2+-activated K+ (BK) channels are responsible for fast membrane repolarization and small time constants of mature IHCs. For unknown reasons, they activate at around -75 mV with a voltage of half-maximum activation (Vhalf) of -50 mV although being largely insensitive to Ca2+ influx. Ca2+-independent activation of BK channels was observed by others in heterologous expression systems if γ subunits leucine-rich repeat-containing protein (LRRC)26 (γ1) and LRRC52 (γ2) were coexpressed with the pore-forming BKα subunit, which shifted Vhalf by -140 and -100 mV, respectively. Using nested PCR, we consistently detected transcripts for LRRC52 but not for LRRC26 in IHCs of 3-wk-old mice. Confocal immunohistochemistry showed synchronous up-regulation of LRRC52 protein with BKα at the onset of hearing. Colocalization of LRRC52 protein and BKα at the IHC neck within ≤40 nm was specified using an in situ proximity ligation assay. Mice deficient for the voltage-gated Cav1.3 Ca2+ channel encoded by Cacna1d do not express BKα protein. LRRC52 protein was neither expressed in IHCs of BKα nor in IHCs of Cav1.3 knockout mice. Together, LRRC52 is a γ2 subunit of BK channel complexes and is a strong candidate for causing the Ca2+-independent activation of BK currents at negative membrane potentials in mouse IHCs.-Lang, I., Jung, M., Niemeyer, B. A., Ruth, P., Engel, J. Expression of the LRRC52 γ subunit (γ2) may provide Ca2+-independent activation of BK currents in mouse inner hair cells.
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Affiliation(s)
- Isabelle Lang
- Hearing Research, Department of Biophysics and Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Martin Jung
- Department of Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Department of Biophysics and Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Peter Ruth
- Institute of Pharmacy, Department of Pharmacology, Toxicology and Clinical Pharmacy, University of Tübingen, Tübingen, Germany
| | - Jutta Engel
- Hearing Research, Department of Biophysics and Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
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17
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Alansary D, Niemeyer BA. Stepping out of the shadow: STIM2 promotes IL-3-induced cytokine release. Sci Signal 2019; 12:12/576/eaax0210. [PMID: 30967511 DOI: 10.1126/scisignal.aax0210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Basophils are a small population of innate immune cells, but their release of the cytokine interleukin-4 (IL-4) is important for mounting an efficient immune response against distinct parasites. Yoshikawa et al (in the 9 April 2019 issue) showed that whereas STIM1 is essential for IL-4 release after stimulation of FcεRI, STIM2 mediates a delayed IL-3/IL-33-induced IL-4 release independent of STIM1.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany.
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18
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Schmidt B, Alansary D, Bogeski I, Niemeyer BA, Rieger H. Reaction-diffusion model for STIM-ORAI interaction: The role of ROS and mutations. J Theor Biol 2019; 470:64-75. [PMID: 30853394 DOI: 10.1016/j.jtbi.2019.02.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 02/13/2019] [Accepted: 02/18/2019] [Indexed: 11/30/2022]
Abstract
Release of Ca2+ from endoplasmatic retriculum (ER) Ca2+ stores causes stromal interaction molecules (STIM) in the ER membrane and ORAI proteins in the plasma membrane (PM) to interact and form the Ca2+ release activated Ca2+ (CRAC) channels, which represent a major Ca2+ entry route in non-excitable cells and thus control various cell functions. It is experimentally possible to mutate ORAI1 proteins and therefore modify, especially block, the Ca2+ influx into the cell. On the basis of the model of Hoover and Lewis (2011), we formulate a reaction-diffusion model to quantify the STIM1-ORAI1 interaction during CRAC channel formation and analyze different ORAI1 channel stoichiometries and different ratios of STIM1 and ORAI1 in comparison with experimental data. We incorporate the inhibition of ORAI1 channels by ROS into our model and calculate its contribution to the CRAC channel amplitude. We observe a large decrease of the CRAC channel amplitude evoked by mutations of ORAI1 proteins.
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Affiliation(s)
- Barbara Schmidt
- Center for Biophysics & Department of Theoretical Physics, Saarland University, Saarbrücken 66041, Germany; Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany; Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany.
| | - Dalia Alansary
- Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany.
| | - Ivan Bogeski
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany; Molecular Physiology, Institute of Cardiovascular Physiology, University Medical Center Georg-August-University, Göttingen 37073, Germany.
| | - Barbara A Niemeyer
- Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg 66421, Germany.
| | - Heiko Rieger
- Center for Biophysics & Department of Theoretical Physics, Saarland University, Saarbrücken 66041, Germany.
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19
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Diener C, Hart M, Alansary D, Poth V, Walch-Rückheim B, Menegatti J, Grässer F, Fehlmann T, Rheinheimer S, Niemeyer BA, Lenhof HP, Keller A, Meese E. Modulation of intracellular calcium signaling by microRNA-34a-5p. Cell Death Dis 2018; 9:1008. [PMID: 30262862 PMCID: PMC6160487 DOI: 10.1038/s41419-018-1050-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 09/10/2018] [Accepted: 09/10/2018] [Indexed: 12/21/2022]
Abstract
Adjusting intracellular calcium signaling is an important feature in the regulation of immune cell function and survival. Here we show that miR-34a-5p, a small non-coding RNA that is deregulated in many common diseases, is a regulator of store-operated Ca2+ entry (SOCE) and calcineurin signaling. Upon miR-34a-5p overexpression, we observed both a decreased depletion of ER calcium content and a decreased Ca2+ influx through Ca2+ release-activated Ca2+ channels. Based on an in silico target prediction we identified multiple miR-34a-5p target genes within both pathways that are implicated in the balance between T-cell activation and apoptosis including ITPR2, CAMLG, STIM1, ORAI3, RCAN1, PPP3R1, and NFATC4. Functional analysis revealed a decrease in Ca2+ activated calcineurin pathway activity measured by a reduced IL-2 secretion due to miR-34a-5p overexpression. Impacting SOCE and/or downstream calcineurin/NFAT signaling by miR-34a-5p offers a possible future approach to manipulate immune cells for clinical interventions.
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Affiliation(s)
- Caroline Diener
- Institute of Human Genetics, Saarland University, 66421, Homburg, Germany.
| | - Martin Hart
- Institute of Human Genetics, Saarland University, 66421, Homburg, Germany
| | - Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421, Homburg, Germany
| | - Vanessa Poth
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421, Homburg, Germany
| | - Barbara Walch-Rückheim
- Institute of Virology and Center of Human and Molecular Biology, Saarland University, 66421, Homburg, Germany
| | - Jennifer Menegatti
- Institute of Virology and Center of Human and Molecular Biology, Medical School, Saarland University, 66421, Homburg, Germany
| | - Friedrich Grässer
- Institute of Virology and Center of Human and Molecular Biology, Medical School, Saarland University, 66421, Homburg, Germany
| | - Tobias Fehlmann
- Chair for Clinical Bioinformatics, Saarland University, 66123, Saarbrücken, Germany
| | | | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421, Homburg, Germany
| | - Hans-Peter Lenhof
- Center for Bioinformatics, Saarland Informatics Campus, Saarland University, 66123, Saarbrücken, Germany
| | - Andreas Keller
- Chair for Clinical Bioinformatics, Saarland University, 66123, Saarbrücken, Germany
| | - Eckart Meese
- Institute of Human Genetics, Saarland University, 66421, Homburg, Germany
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20
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Bunse L, Pusch S, Bunse T, Sahm F, Sanghvi K, Friedrich M, Alansary D, Sonner JK, Green E, Deumelandt K, Kilian M, Neftel C, Uhlig S, Kessler T, von Landenberg A, Berghoff AS, Marsh K, Steadman M, Zhu D, Nicolay B, Wiestler B, Breckwoldt MO, Al-Ali R, Karcher-Bausch S, Bozza M, Oezen I, Kramer M, Meyer J, Habel A, Eisel J, Poschet G, Weller M, Preusser M, Nadji-Ohl M, Thon N, Burger MC, Harter PN, Ratliff M, Harbottle R, Benner A, Schrimpf D, Okun J, Herold-Mende C, Turcan S, Kaulfuss S, Hess-Stumpp H, Bieback K, Cahill DP, Plate KH, Hänggi D, Dorsch M, Suvà ML, Niemeyer BA, von Deimling A, Wick W, Platten M. Suppression of antitumor T cell immunity by the oncometabolite (R)-2-hydroxyglutarate. Nat Med 2018; 24:1192-1203. [PMID: 29988124 DOI: 10.1038/s41591-018-0095-6] [Citation(s) in RCA: 314] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 03/27/2018] [Indexed: 12/22/2022]
Abstract
The oncometabolite (R)-2-hydroxyglutarate (R-2-HG) produced by isocitrate dehydrogenase (IDH) mutations promotes gliomagenesis via DNA and histone methylation. Here, we identify an additional activity of R-2-HG: tumor cell-derived R-2-HG is taken up by T cells where it induces a perturbation of nuclear factor of activated T cells transcriptional activity and polyamine biosynthesis, resulting in suppression of T cell activity. IDH1-mutant gliomas display reduced T cell abundance and altered calcium signaling. Antitumor immunity to experimental syngeneic IDH1-mutant tumors induced by IDH1-specific vaccine or checkpoint inhibition is improved by inhibition of the neomorphic enzymatic function of mutant IDH1. These data attribute a novel, non-tumor cell-autonomous role to an oncometabolite in shaping the tumor immune microenvironment.
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Affiliation(s)
- Lukas Bunse
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Neurology, Heidelberg University Medical Center, Heidelberg, Germany
- National Center for Tumor Diseases Heidelberg, DKTK, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Stefan Pusch
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Theresa Bunse
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- National Center for Tumor Diseases Heidelberg, DKTK, Heidelberg, Germany
- Department of Neurology, University Hospital and Medical Faculty Mannheim, Mannheim, Germany
| | - Felix Sahm
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Khwab Sanghvi
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Mirco Friedrich
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, Germany
| | - Jana K Sonner
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Edward Green
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Katrin Deumelandt
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Michael Kilian
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Cyril Neftel
- Broad Institute of Harvard and MIT and Department of Pathology and Center for Cancer Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Stefanie Uhlig
- FlowCore Mannheim and Institute of Transfusion Medicine and Immunology, Mannheim, Germany
| | - Tobias Kessler
- Department of Neurology, Heidelberg University Medical Center, Heidelberg, Germany
- National Center for Tumor Diseases Heidelberg, DKTK, Heidelberg, Germany
- DKTK CCU Neurooncology, DKFZ, Heidelberg, Germany
| | - Anna von Landenberg
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Anna S Berghoff
- DKTK CCU Neurooncology, DKFZ, Heidelberg, Germany
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
- CNS Tumors Unit, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
| | - Kelly Marsh
- Agios Pharmaceuticals, Inc., Cambridge, MA, USA
| | | | - Dongwei Zhu
- Agios Pharmaceuticals, Inc., Cambridge, MA, USA
| | | | - Benedikt Wiestler
- Department of Diagnostic and Interventional Neuroradiology, Neuro-Kopf-Zentrum, Klinikum rechts der Isar, Technical University Munich, Munich, Germany
| | - Michael O Breckwoldt
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Neuroradiology, Heidelberg University Medical Center, Heidelberg, Germany
| | - Ruslan Al-Ali
- Max Eder Junior Group on Low Grade Gliomas, Heidelberg University Medical Center, Heidelberg, Germany
| | - Simone Karcher-Bausch
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Iris Oezen
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Magdalena Kramer
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jochen Meyer
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Antje Habel
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Jessica Eisel
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Gernot Poschet
- Center for Organismal Studies, University Heidelberg, Heidelberg, Germany
| | - Michael Weller
- Department of Neurology, University Hospital and University of Zurich, Zurich, Switzerland
| | - Matthias Preusser
- CNS Tumors Unit, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria
- Department for Medicine I, Clinical Division of Oncology, Medical University of Vienna, Vienna, Austria
| | - Minou Nadji-Ohl
- Department of Neurosurgery, Stuttgart Clinics, Stuttgart, Germany
| | - Niklas Thon
- Department of Neurosurgery, Klinikum Grosshadern, Ludwig-Maximilians-University, Munich, Germany
| | - Michael C Burger
- Dr. Senckenberg Institute of Neurooncology, Goethe University Hospital, Frankfurt, Germany
- DKTK Partner Site Frankfurt/Mainz, Frankfurt, Germany
| | - Patrick N Harter
- DKTK Partner Site Frankfurt/Mainz, Frankfurt, Germany
- Institute of Neurology (Edinger Institute), University Hospital and Medical Faculty, Goethe University, Frankfurt, Germany
| | - Miriam Ratliff
- DKTK CCU Neurooncology, DKFZ, Heidelberg, Germany
- Neurosurgery Clinic, University Hospital Mannheim, Mannheim, Germany
| | | | - Axel Benner
- Division of Biostatistics, DKFZ, Heidelberg, Germany
| | - Daniel Schrimpf
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
- DKTK CCU Neuropathology, DKFZ, Heidelberg, Germany
| | - Jürgen Okun
- Metabolic Center Heidelberg, University Children's Hospital, Heidelberg, Germany
| | - Christel Herold-Mende
- Division of Experimental Neurosurgery, Department of Neurosurgery, Heidelberg University Medical Center, Heidelberg, Germany
| | - Sevin Turcan
- Max Eder Junior Group on Low Grade Gliomas, Heidelberg University Medical Center, Heidelberg, Germany
| | - Stefan Kaulfuss
- Research and Development, Pharmaceuticals, Bayer AG, Berlin, Germany
| | | | - Karen Bieback
- FlowCore Mannheim and Institute of Transfusion Medicine and Immunology, Mannheim, Germany
| | - Daniel P Cahill
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Karl H Plate
- DKTK Partner Site Frankfurt/Mainz, Frankfurt, Germany
- Institute of Neurology (Edinger Institute), University Hospital and Medical Faculty, Goethe University, Frankfurt, Germany
| | - Daniel Hänggi
- Neurosurgery Clinic, University Hospital Mannheim, Mannheim, Germany
| | | | - Mario L Suvà
- Broad Institute of Harvard and MIT and Department of Pathology and Center for Cancer Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, Germany
| | - Andreas von Deimling
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
- Department of Neuropathology, Heidelberg University Medical Center, Heidelberg, Germany
| | - Wolfgang Wick
- Department of Neurology, Heidelberg University Medical Center, Heidelberg, Germany
- National Center for Tumor Diseases Heidelberg, DKTK, Heidelberg, Germany
- DKTK CCU Neurooncology, DKFZ, Heidelberg, Germany
| | - Michael Platten
- German Cancer Consortium (DKTK) Clinical Cooperation Unit (CCU) Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
- Department of Neurology, Heidelberg University Medical Center, Heidelberg, Germany.
- National Center for Tumor Diseases Heidelberg, DKTK, Heidelberg, Germany.
- Department of Neurology, University Hospital and Medical Faculty Mannheim, Mannheim, Germany.
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21
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Zhou X, Friedmann KS, Lyrmann H, Zhou Y, Schoppmeyer R, Knörck A, Mang S, Hoxha C, Angenendt A, Backes CS, Mangerich C, Zhao R, Cappello S, Schwär G, Hässig C, Neef M, Bufe B, Zufall F, Kruse K, Niemeyer BA, Lis A, Qu B, Kummerow C, Schwarz EC, Hoth M. A calcium optimum for cytotoxic T lymphocyte and natural killer cell cytotoxicity. J Physiol 2018; 596:2681-2698. [PMID: 29368348 DOI: 10.1113/jp274964] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/04/2018] [Indexed: 12/13/2022] Open
Abstract
KEY POINTS Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells are required to eliminate cancer cells. We analysed the Ca2+ dependence of CTL and NK cell cytotoxicity and found that in particular CTLs have a very low optimum of [Ca2+ ]i (between 122 and 334 nm) and [Ca2+ ]o (between 23 and 625 μm) for efficient cancer cell elimination, well below blood plasma Ca2+ levels. As predicted from these results, partial down-regulation of the Ca2+ channel Orai1 in CTLs paradoxically increases perforin-dependent cancer cell killing. Lytic granule release at the immune synapse between CTLs and cancer cells has a Ca2+ optimum compatible with this low Ca2+ optimum for efficient cancer cell killing, whereas the Ca2+ optimum for CTL migration is slightly higher and proliferation increases monotonously with increasing [Ca2+ ]o . We propose that a partial inhibition of Ca2+ signals by specific Orai1 blockers at submaximal concentrations could contribute to tumour elimination. ABSTRACT Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells are required to protect the human body against cancer. Ca2+ is a key metabolic factor for lymphocyte function and cancer homeostasis. We analysed the Ca2+ dependence of CTL and NK cell cytotoxicity against cancer cells and found that CTLs have a bell-shaped Ca2+ dependence with an optimum for cancer cell elimination at rather low [Ca2+ ]o (23-625 μm) and [Ca2+ ]i (122-334 nm). This finding predicts that a partial inhibition of Orai1 should increase (rather than decrease) cytotoxicity of CTLs at [Ca2+ ]o higher than 625 μm. We tested this hypothesis in CTLs and indeed found that partial down-regulation of Orai1 by siRNA increases the efficiency of cancer cell killing. We found two mechanisms that may account for the Ca2+ optimum of cancer cell killing: (1) migration velocity and persistence have a moderate optimum between 500 and 1000 μm [Ca2+ ]o in CTLs, and (2) lytic granule release at the immune synapse between CTLs and cancer cells is increased at 146 μm compared to 3 or 800 μm, compatible with the Ca2+ optimum for cancer cell killing. It has been demonstrated in many cancer cell types that Orai1-dependent Ca2+ signals enhance proliferation. We propose that a decrease of [Ca2+ ]o or partial inhibition of Orai1 activity by selective blockers in the tumour microenvironment could efficiently reduce cancer growth by simultaneously increasing CTL and NK cell cytotoxicity and decreasing cancer cell proliferation.
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Affiliation(s)
- Xiao Zhou
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Kim S Friedmann
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Hélène Lyrmann
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Yan Zhou
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Rouven Schoppmeyer
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Arne Knörck
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Sebastian Mang
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Cora Hoxha
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Adrian Angenendt
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Christian S Backes
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Carmen Mangerich
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Renping Zhao
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Sabrina Cappello
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany.,Cardiovascular Physiology, University Medical Center, University of Göttingen, Göttingen, 37073, Germany
| | - Gertrud Schwär
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Carmen Hässig
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Marc Neef
- Department of Theoretical Physics, Saarland University, Saarbrücken, 66041, Germany
| | - Bernd Bufe
- Physiology, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Frank Zufall
- Physiology, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Karsten Kruse
- Department of Theoretical Physics, Saarland University, Saarbrücken, 66041, Germany.,Department of Biochemistry and Theoretical Physics, University of Geneva, Geneva, 1211, Switzerland
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Annette Lis
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Carsten Kummerow
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Eva C Schwarz
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
| | - Markus Hoth
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg, 66421, Germany
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22
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Bost A, Shaib AH, Schwarz Y, Niemeyer BA, Becherer U. Large dense-core vesicle exocytosis from mouse dorsal root ganglion neurons is regulated by neuropeptide Y. Neuroscience 2017; 346:1-13. [PMID: 28089870 DOI: 10.1016/j.neuroscience.2017.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 12/12/2022]
Abstract
Peptidergic dorsal root ganglion (DRG) neurons transmit sensory and nociceptive information from the periphery to the central nervous system. Their synaptic activity is profoundly affected by neuromodulatory peptides stored and released from large dense-core vesicles (LDCVs). However, the mechanism of peptide secretion from DRG neurons is poorly understood. Using total internal reflection fluorescence microscopy (TIRFM), we visualized individual LDCVs loaded with fluorescent neuropeptide Y (NPY) and analyzed their stimulation-dependent release. We tested several protocols and found an overall low stimulation-secretion coupling that increased after raising intracellular Ca2+ concentration by applying a weak pre-stimulus. Interestingly, the stimulation protocol also influenced the mechanism of LDCV fusion. Depolarization of DRG neurons with a solution containing 60mM KCl triggered full fusion, kiss-and-run, and kiss-and-stay exocytosis with equal frequency. In contrast, field electrode stimulation primarily induced full fusion exocytosis. Finally, our results indicate that NPY can promote LDCV secretion. These results shed new light on the mechanism of NPY action during modulation of DRG neuron activity, an important pathway in the treatment of chronic pain.
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Affiliation(s)
- Anneka Bost
- Institute of Physiology, CIPMM, Saarland University, 66421 Homburg/Saar, Germany
| | - Ali H Shaib
- Institute of Physiology, CIPMM, Saarland University, 66421 Homburg/Saar, Germany
| | - Yvonne Schwarz
- Institute of Physiology, CIPMM, Saarland University, 66421 Homburg/Saar, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, CIPMM, Saarland University, 66421 Homburg/Saar, Germany
| | - Ute Becherer
- Institute of Physiology, CIPMM, Saarland University, 66421 Homburg/Saar, Germany.
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23
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Abstract
Cysteines are among the least abundant amino acids found in proteins. Due to their unique nucleophilic thiol group, they are able to undergo a broad range of chemical modifications besides their known role in disulfide formation, such as S-sulfenylation (-SOH), S-sulfinylation (-SO(2)H), S-sufonylation (-SO(3)H), S-glutathionylation (-SSG), and S-sulfhydration (-SSH), among others. These posttranslational modifications can be irreversible and act as transitional modifiers or as reversible on-off switches for the function of proteins. Disturbances of the redox homeostasis, for example, in situations of increased oxidative stress, can contribute to a range of diseases. Because Ca2+ signaling mediated by store-operated calcium entry (SOCE) is involved in a plethora of cellular responses, the cross-talk between reactive oxygen species (ROS) and Ca2+ is critical for homeostatic control. Identification of calcium regulatory protein targets of thiol redox modifications is needed to understand their role in biology and disease.
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Affiliation(s)
- Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany.
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24
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Alansary D, Schmidt B, Dörr K, Bogeski I, Rieger H, Kless A, Niemeyer BA. Thiol dependent intramolecular locking of Orai1 channels. Sci Rep 2016; 6:33347. [PMID: 27624281 PMCID: PMC5022029 DOI: 10.1038/srep33347] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/25/2016] [Indexed: 12/11/2022] Open
Abstract
Store-operated Ca2+ entry mediated by STIM1-gated Orai1 channels is essential to activate immune cells and its inhibition or gain-of-function can lead to immune dysfunction and other pathologies. Reactive oxygen species interacting with cysteine residues can alter protein function. Pretreatment of the Ca2+ selective Orai1 with the oxidant H2O2 reduces ICRAC with C195, distant to the pore, being its major redox sensor. However, the mechanism of inhibition remained elusive. Here we combine experimental and theoretical approaches and show that oxidation of Orai1 leads to reduced subunit interaction, slows diffusion and that either oxidized C195 or its oxidomimetic mutation C195D located at the exit of transmembrane helix 3 virtually eliminates channel activation by intramolecular interaction with S239 of transmembrane helix 4, thereby locking the channel in a closed conformation. Our results demonstrate a novel mechanistic model for ROS-mediated inhibition of Orai1 and identify a candidate residue for pharmaceutical intervention.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Barbara Schmidt
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany.,Department of Biophysics, Saarland University, 66421 Homburg, Germany.,Department of Theoretical Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Kathrin Dörr
- Molecular Biophysics, Saarland University, 66421 Homburg, Germany
| | - Ivan Bogeski
- Department of Biophysics, Saarland University, 66421 Homburg, Germany
| | - Heiko Rieger
- Department of Theoretical Physics, Saarland University, 66041 Saarbrücken, Germany
| | - Achim Kless
- Gruenenthal Innovation, Drug Discovery Technologies, Gruenenthal GmbH, 52078 Aachen, Germany
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25
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Peckys DB, Alansary D, Niemeyer BA, de Jonge N. Visualizing Quantum Dot Labeled ORAI1 Proteins in Intact Cells Via Correlative Light and Electron Microscopy. Microsc Microanal 2016; 22:902-912. [PMID: 27515473 DOI: 10.1017/s1431927616011491] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
ORAI1 proteins are ion channel subunits and the essential pore-forming units of the calcium release-activated calcium channel complex essential for T-cell activation and many other cellular processes. In this study, we used environmental scanning electron microscopy (ESEM) with scanning transmission electron microscopy (STEM) detection to image plasma membrane expressed ORAI1 proteins in whole Jurkat T cells in the liquid state. Utilizing a stably transfected Jurkat T cell clone expressing human ORAI1 with an extracellular human influenza hemagglutinin (HA) tag we investigated if liquid-phase STEM can be applied to detect recombinant surface expressed protein. Streptavidin coated quantum dots were coupled in a one-to-one stoichiometry to ORAI1 proteins detected by biotinylated anti-HA fragmented antibody fragments. High-resolution electron microscopic images revealed the individual label locations from which protein pair distances were determined. These data were analyzed using the pair correlation function and, in addition, an analysis of cluster size and frequency was performed. ORAI1 was found to be present in hexamers in a small fraction only, and ORAI1 resided mostly in monomers and dimers.
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Affiliation(s)
- Diana B Peckys
- 1Department of Molecular Biophysics,Saarland University,CIPMM,66421 Homburg,Germany
| | - Dalia Alansary
- 1Department of Molecular Biophysics,Saarland University,CIPMM,66421 Homburg,Germany
| | - Barbara A Niemeyer
- 1Department of Molecular Biophysics,Saarland University,CIPMM,66421 Homburg,Germany
| | - Niels de Jonge
- 2INM - Leibniz Institute for New Materials,66123 Saarbrücken,Germany
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26
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Dörr K, Kilch T, Kappel S, Alansary D, Schwär G, Niemeyer BA, Peinelt C. Cell type-specific glycosylation of Orai1 modulates store-operated Ca2+ entry. Sci Signal 2016; 9:ra25. [PMID: 26956484 DOI: 10.1126/scisignal.aaa9913] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
N-glycosylation of cell surface proteins affects protein function, stability, and interaction with other proteins. Orai channels, which mediate store-operated Ca(2+) entry (SOCE), are composed of N-glycosylated subunits. Upon activation by Ca(2+) sensor proteins (stromal interaction molecules STIM1 or STIM2) in the endoplasmic reticulum, Orai Ca(2+) channels in the plasma membrane mediate Ca(2+) influx. Lectins are carbohydrate-binding proteins, and Siglecs are a family of sialic acid-binding lectins with immunoglobulin-like repeats. Using Western blot analysis and lectin-binding assays from various primary human cells and cancer cell lines, we found that glycosylation of Orai1 is cell type-specific. Ca(2+) imaging experiments and patch-clamp experiments revealed that mutation of the only glycosylation site of Orai1 (Orai1N223A) enhanced SOCE in Jurkat T cells. Knockdown of the sialyltransferase ST6GAL1 reduced α-2,6-linked sialic acids in the glycan structure of Orai1 and was associated with increased Ca(2+) entry in Jurkat T cells. In human mast cells, inhibition of sialyl sulfation altered the N-glycan of Orai1 (and other proteins) and increased SOCE. These data suggest that cell type-specific glycosylation influences the interaction of Orai1 with specific lectins, such as Siglecs, which then attenuates SOCE. In summary, the glycosylation state of Orai1 influences SOCE-mediated Ca(2+) signaling and, thus, may contribute to pathophysiological Ca(2+) signaling observed in immune disease and cancer.
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Affiliation(s)
- Kathrin Dörr
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Tatiana Kilch
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Sven Kappel
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany
| | - Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Gertrud Schwär
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Christine Peinelt
- Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, Homburg 66421, Germany. Center of Human and Molecular Biology, Saarland University, Homburg 66421, Germany.
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27
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Saul S, Gibhardt CS, Schmidt B, Lis A, Pasieka B, Conrad D, Jung P, Gaupp R, Wonnenberg B, Diler E, Stanisz H, Vogt T, Schwarz EC, Bischoff M, Herrmann M, Tschernig T, Kappl R, Rieger H, Niemeyer BA, Bogeski I. A calcium-redox feedback loop controls human monocyte immune responses: The role of ORAI Ca2+ channels. Sci Signal 2016; 9:ra26. [PMID: 26956485 DOI: 10.1126/scisignal.aaf1639] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In phagocytes, pathogen recognition is followed by Ca(2+) mobilization and NADPH oxidase 2 (NOX2)-mediated "oxidative burst," which involves the rapid production of large amounts of reactive oxygen species (ROS). We showed that ORAI Ca(2+) channels control store-operated Ca(2+) entry, ROS production, and bacterial killing in primary human monocytes. ROS inactivate ORAI channels that lack an ORAI3 subunit. Staphylococcal infection of mice reduced the expression of the gene encoding the redox-sensitive Orai1 and increased the expression of the gene encoding the redox-insensitive Orai3 in the lungs or in bronchoalveolar lavages. A similar switch from ORAI1 to ORAI3 occurred in primary human monocytes exposed to bacterial peptides in culture. These alterations in ORAI1 and ORAI3 abundance shifted the channel assembly toward a more redox-insensitive configuration. Accordingly, silencing ORAI3 increased the redox sensitivity of the channel and enhanced oxidation-induced inhibition of NOX2. We generated a mathematical model that predicted additional features of the Ca(2+)-redox interplay. Our results identified the ORAI-NOX2 feedback loop as a determinant of monocyte immune responses.
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Affiliation(s)
- Stephanie Saul
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Christine S Gibhardt
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Barbara Schmidt
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany. Department of Theoretical Physics, Saarland University, Saarbrücken 66123, Germany. Molecular Biophysics, CIPMM, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Annette Lis
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Bastian Pasieka
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - David Conrad
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Philipp Jung
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg 66421, Germany
| | - Rosmarie Gaupp
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg 66421, Germany
| | - Bodo Wonnenberg
- Department of Anatomy, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Ebru Diler
- Department of Anatomy, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Hedwig Stanisz
- Department of Dermatology, Venereology and Allergology, University Hospital of Saarland, Homburg 66421, Germany
| | - Thomas Vogt
- Department of Dermatology, Venereology and Allergology, University Hospital of Saarland, Homburg 66421, Germany
| | - Eva C Schwarz
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Markus Bischoff
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg 66421, Germany
| | - Mathias Herrmann
- Institute of Medical Microbiology and Hygiene, Saarland University, Homburg 66421, Germany
| | - Thomas Tschernig
- Department of Anatomy, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Reinhard Kappl
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Heiko Rieger
- Department of Theoretical Physics, Saarland University, Saarbrücken 66123, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, CIPMM, School of Medicine, Saarland University, Homburg 66421, Germany
| | - Ivan Bogeski
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPPM), School of Medicine, Saarland University, Homburg 66421, Germany.
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28
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Abstract
A wide variety of cellular function depends on the dynamics of intracellular Ca(2+) signals. Especially for relatively slow and lasting processes such as gene expression, cell proliferation, and often migration, cells rely on the store-operated Ca(2+) entry (SOCE) pathway, which is particularly prominent in immune cells. SOCE is initiated by the sensor proteins (STIM1, STIM2) located within the endoplasmic reticulum (ER) registering the Ca(2+) concentration within the ER, and upon its depletion, cluster and trap Orai (Orai1-3) proteins located in the plasma membrane (PM) into ER-PM junctions. These regions become sites of highly selective Ca(2+) entry predominantly through Orai1-assembled channels, which, among other effector functions, is necessary for triggering NFAT translocation into the nucleus. What is less clear is how the spatial and temporal spread of intracellular Ca(2+) is shaped and regulated by differential expression of the individual SOCE genes and their splice variants, their heteromeric combinations and pre- and posttranslational modifications. This review focuses on principle mechanisms regulating expression, splicing, and targeting of Ca(2+) release-activated Ca(2+) (CRAC) channels.
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Affiliation(s)
- Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, Saarland University, Homburg, Germany
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29
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Miederer AM, Alansary D, Schwär G, Lee PH, Jung M, Helms V, Niemeyer BA. A STIM2 splice variant negatively regulates store-operated calcium entry. Nat Commun 2015; 6:6899. [PMID: 25896806 PMCID: PMC4411291 DOI: 10.1038/ncomms7899] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 03/11/2015] [Indexed: 02/01/2023] Open
Abstract
Cellular homeostasis relies upon precise regulation of Ca2+ concentration. Stromal interaction molecule (STIM) proteins regulate store-operated calcium entry (SOCE) by sensing Ca2+ concentration in the ER and forming oligomers to trigger Ca2+ entry through plasma membrane-localized Orai1 channels. Here we characterize a STIM2 splice variant, STIM2.1, which retains an additional exon within the region encoding the channel-activating domain. Expression of STIM2.1 is ubiquitous but its abundance relative to the more common STIM2.2 variant is dependent upon cell type and highest in naive T cells. STIM2.1 knockdown increases SOCE in naive CD4+ T cells, whereas knockdown of STIM2.2 decreases SOCE. Conversely, overexpression of STIM2.1, but not STIM2.2, decreases SOCE, indicating its inhibitory role. STIM2.1 interaction with Orai1 is impaired and prevents Orai1 activation, but STIM2.1 shows increased affinity towards calmodulin. Our results imply STIM2.1 as an additional player tuning Orai1 activation in vivo. STIM proteins sense calcium depletion in the endoplasmic reticulum and in response activate calcium influx through Orai1 channels located at the plasma membrane. Here, Miederer et al. identify a novel splice variant of STIM2 that fails to interact with and activate Orai1 and may act to fine-tune cellular calcium homeostasis by negatively regulating calcium influx.
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Affiliation(s)
- Anna-Maria Miederer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Building 48, Homburg 66421, Germany
| | - Dalia Alansary
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Building 48, Homburg 66421, Germany
| | - Gertrud Schwär
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Building 48, Homburg 66421, Germany.,Department of Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Homburg 66421, Germany
| | - Po-Hsien Lee
- Center for Bioinformatics, Saarland University, Campus E2 1, R. 315, PO Box 151150, Saarbrücken 66041, Germany
| | - Martin Jung
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Building 44, Homburg 66421, Germany
| | - Volkhard Helms
- Center for Bioinformatics, Saarland University, Campus E2 1, R. 315, PO Box 151150, Saarbrücken 66041, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, Building 48, Homburg 66421, Germany
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30
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Alansary D, Bogeski I, Niemeyer BA. Facilitation of Orai3 targeting and store-operated function by Orai1. Biochim Biophys Acta 2015; 1853:1541-50. [PMID: 25791427 DOI: 10.1016/j.bbamcr.2015.03.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 03/04/2015] [Accepted: 03/10/2015] [Indexed: 11/27/2022]
Abstract
Orai1 subunits interacting with STIM1 molecules comprise the major components responsible for calcium release-activated calcium (CRAC) channels. The homologs Orai2 and Orai3 yield smaller store-operated currents when overexpressed and are mostly unable to substitute Orai1. Orai3 subunits are also essential components of store independent channel complexes and also tune inhibition of ICRAC by reactive oxygen species. Here we use patch-clamp, microscopy, Ca(2+)-imaging and biochemical experiments to investigate the interdependence of Orai2, Orai3 and Orai1. We demonstrate that store-operation and localization of Orai3 but not of Orai2 to STIM1 clusters in HEK cells or to the immunological synapse in T cells is facilitated by Orai1 while Orai3's store-independent activity remains unaffected. On the other hand, one Orai3 subunit confers redox-resistance to heteromeric channels. The inefficient store operation of Orai3 is partly due to the lack of three critical C-terminal residues, the insertion of which improves interaction with STIM1 and abrogates Orai3's dependence on Orai1. Our results suggest that Orai3 down-tunes efficient STIM1 gating when in a heteromeric complex with Orai1.
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Affiliation(s)
- Dalia Alansary
- Molecular Biophysics, School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Ivan Bogeski
- Biophysics, Center for Integrated Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Barbara A Niemeyer
- Molecular Biophysics, School of Medicine, Saarland University, 66421 Homburg, Germany.
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31
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Miederer AM, Alansary D, Schwaer G, Jung M, Niemeyer BA. A Novel STIM2 Splice Variant Functions as a Break for STIM Mediated Activation of Orai Calcium Channels. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.3099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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32
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Niemeyer BA. Tuning the Taps: STIM1 and STIM2 Regulatory Mechanisms. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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33
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Abstract
Reactive oxygen species and reactive nitrogen species (ROS/RNS) are often by-products of biochemical reactions, but are increasingly recognized as important second messengers involved in regulation of distinct cellular functions. Mild and reversible oxidation of certain amino acids within protein polypeptide chains is known to precisely control the function of transcription factors, protein kinases and phosphatases, receptors, pumps, ion channels, and so on. Conversely, under pathological conditions, high amounts of oxidants irreversibly oxidize DNA, lipids, and proteins and have deleterious effects on cells, ultimately causing cell death. ROS/RNS can thus be involved in the initiation and progression of many pathological conditions. Within this Forum, seven reviews and one original article summarize the current knowledge regarding redox regulation of various ion channels and ion conducting receptors. These include the recently identified mitochondrial Ca2+ uniporter and Orai Ca2+ channels, as well as selected members of the families of transient receptor potential, voltage-gated Ca2+, P2X, voltage-gated K+, and IP3R/RyR channels. In summary, all authors agree on the functional importance of redox-ion channel interplay. However, it is also clear that this is an emerging field of research where much has to be learned about intra- and extracellular sources, concentrations, and types of oxidants. Given their often short-lived nature and effective cellular buffering systems, the development of tools to measure local ROS production in living cells as well as detailed proteomic approaches to pinpoint protein targets and redox modifications are of importance.
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Affiliation(s)
- Ivan Bogeski
- Department of Biophysics, University of Saarland , Homburg, Germany
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Stanisz H, Saul S, Müller CSL, Kappl R, Niemeyer BA, Vogt T, Hoth M, Roesch A, Bogeski I. Inverse regulation of melanoma growth and migration by Orai1/STIM2-dependent calcium entry. Pigment Cell Melanoma Res 2014; 27:442-53. [PMID: 24472175 DOI: 10.1111/pcmr.12222] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 01/24/2014] [Indexed: 12/29/2022]
Abstract
Spontaneous melanoma phenotype switching is controlled by unknown environmental factors and may determine melanoma outcome and responsiveness to anticancer therapy. We show that Orai1 and STIM2 are highly expressed and control store-operated Ca(2+) entry in human melanoma. Lower extracellular Ca(2+) or silencing of Orai1/STIM2 caused a decrease in intracellular Ca(2+) , which correlated with enhanced proliferation and increased expression of microphthalmia-associated transcription factor, a marker for proliferative melanoma phenotype. In contrast, the invasive and migratory potential of melanoma cells was reduced upon silencing of Orai1 and/or STIM2. Accordingly, markers for a non-proliferative, tumor-maintaining phenotype such as JARID1B and Brn2 decreased. Immunohistochemical staining of primary melanomas and lymph node metastases revealed a heterogeneous distribution of Orai1 and STIM2 with elevated expression in the invasive rim of the tumor. In summary, our results support a dynamic model in which Orai1 and STIM2 inversely control melanoma growth and invasion. Pharmacological tuning of Orai1 and particularly STIM2 might thus prevent metastatic spread and render melanomas more susceptible to conventional therapy.
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Affiliation(s)
- Hedwig Stanisz
- Department of Dermatology, Venereology and Allergology, University Hospital of the Saarland, Homburg, Germany
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35
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Abstract
Plasma-membrane-localized Orai1 ion channel subunits interacting with ER-localized STIM1 molecules comprise the major subunit composition responsible for calcium release-activated calcium channels. STIM1 "translates" the Ca(2+) store content into Orai1 activity, making it a store-operated channel. Surprisingly, in addition to being the physical activator, STIM1 also modulates Orai1 properties, including its inactivation and permeation (see Chapter 1). STIM1 is thus more than a pure Orai1 activator. Within the past 7 years following the discovery of STIM and Orai proteins, the molecular mechanisms of STIM1/Orai1 activity and their functional importance have been studied in great detail. Much less is currently known about the other isoforms STIM2, Orai2, and Orai3. In this chapter, we summarize the current knowledge about STIM2, Orai2, and Orai3 properties and function. Are these homologues mainly modulators of predominantly STIM1/Orai1-mediated complexes or do store-dependent or -independent functions such as regulation of basal Ca(2+) concentration and activation of Orai3-containing complexes by arachidonic acid or by estrogen receptors point toward their "true" physiological function? Is Orai2 the Orai1 of neurons? A major focus of the review is on the functional relevance of STIM2, Orai2, and Orai3, some of which still remains speculative.
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Affiliation(s)
- Markus Hoth
- Department of Biophysics, Saarland University, Homburg, Germany
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36
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Alansary D, Bogeski I, Niemeyer BA. Orai3 Dominantly Modulates Redox Sensitivity and Requires Orai1 to Localize to Microdomains of Store-Operated Activation. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.1830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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37
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Kilch T, Alansary D, Peglow M, Dörr K, Rychkov G, Rieger H, Peinelt C, Niemeyer BA. Mutations of the Ca2+-sensing stromal interaction molecule STIM1 regulate Ca2+ influx by altered oligomerization of STIM1 and by destabilization of the Ca2+ channel Orai1. J Biol Chem 2012; 288:1653-64. [PMID: 23212906 DOI: 10.1074/jbc.m112.417246] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A drop of endoplasmic reticulum Ca(2+) concentration triggers its Ca(2+) ssensor protein stromal interaction molecule 1 (STIM1) to oligomerize and accumulate within endoplasmic reticulum-plasma membrane junctions where it activates Orai1 channels, providing store-operated Ca(2+) entry. To elucidate the functional significance of N-glycosylation sites of STIM1, we created different mutations of asparagine-131 and asparagine-171. STIM1 NN/DQ resulted in a strong gain of function. Patch clamp, Total Internal Reflection Fluorescent (TIRF) microscopy, and fluorescence recovery after photobleaching (FRAP) analyses revealed that expression of STIM1 DQ mutants increases the number of active Orai1 channels and the rate of STIM1 translocation to endoplasmic reticulum-plasma membrane junctions with a decrease in current latency. Surprisingly, co-expression of STIM1 DQ decreased Orai1 protein, altering the STIM1:Orai1 stoichiometry. We describe a novel mathematical tool to delineate the effects of altered STIM1 or Orai1 diffusion parameters from stoichiometrical changes. The mutant uncovers a novel mechanism whereby "superactive" STIM1 DQ leads to altered oligomerization rate constants and to degradation of Orai1 with a change in stoichiometry of activator (STIM1) to effector (Orai1) ratio leading to altered Ca(2+) homeostasis.
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Affiliation(s)
- Tatiana Kilch
- Department of Biophysics, Saarland University, D-66421 Homburg, Germany
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38
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Carreras-Sureda A, Cantero-Recasens G, Rubio-Moscardo F, Kiefer K, Peinelt C, Niemeyer BA, Valverde MA, Vicente R. ORMDL3 modulates store-operated calcium entry and lymphocyte activation. Hum Mol Genet 2012; 22:519-30. [PMID: 23100328 DOI: 10.1093/hmg/dds450] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
T lymphocytes rely on a Ca(2+) signal known as store-operated calcium entry (SOCE) for their activation. This Ca(2+) signal is generated by activation of a T-cell receptor, depletion of endoplasmic reticulum (ER) Ca(2+) stores and activation of Ca(2+) release-activated Ca(2+) currents (I(CRAC)). Here, we report that the ER protein orosomucoid like 3 (ORMDL3), the product of the ORMDL3 gene associated with several autoimmune and/or inflammatory diseases, negatively modulates I(CRAC), SOCE, nuclear factor of activated T cells nuclear translocation and interleukin-2 production. ORMDL3 inhibits the Ca(2+) influx mechanism at the outer mitochondrial membrane, resulting in a Ca(2+)-dependent inhibition of I(CRAC) and reduced SOCE. The effect of ORMDL3 could be mimicked by interventions that decreased mitochondrial Ca(2+) influx and reverted by buffering of cytosolic Ca(2+) or activation of mitochondrial Ca(2+) influx. In conclusion, ORMDL3 modifies key steps in the process of T-lymphocyte activation, providing a functional link between the genetic associations of the ORMDL3 gene with autoimmune and/or inflammatory diseases.
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Affiliation(s)
- Amado Carreras-Sureda
- Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Barcelona 08003, Spain
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Mishina NM, Bogeski I, Bolotin DA, Hoth M, Niemeyer BA, Schultz C, Zagaynova EV, Lukyanov S, Belousov VV. Can we see PIP(3) and hydrogen peroxide with a single probe? Antioxid Redox Signal 2012; 17:505-12. [PMID: 22369174 DOI: 10.1089/ars.2012.4574] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A genetically encoded sensor for parallel measurements of phosphatidylinositol 3-kinase activity and hydrogen peroxide (H(2)O(2)) levels (termed PIP-SHOW) was developed. Upon elevation of local phosphatidylinositol 3,4,5-trisphosphate (PIP(3)) concentration, the sensor translocates from the cytosol to the plasma membrane, while a ratiometric excitation change rapidly and simultaneously reports changes in the concentration of H(2)O(2). The dynamics of PIP(3) and H(2)O(2) generation were monitored in platelet-derived growth factor-stimulated fibroblasts and in T-lymphocytes after formation of an immunological synapse. We suggest that PIP-SHOW can serve as a prototype for many fluorescent sensors with combined readouts.
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Affiliation(s)
- Natalie M Mishina
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia
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40
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Abstract
Store-operated Ca(2+) entry (SOCE) is a widespread mechanism in cells to raise cytosolic Ca(2+) and to refill Ca(2+) stores. T cells critically rely on SOCE mediated by stromal interaction molecules (STIM) and Orai molecules for their activation and regulation of gene transcription; cells such as muscle cells, neurons or melanocytes probably utilize SOCE for the transmission of inducible receptor-mediated function as well as for generalized Ca(2+) homeostasis mechanisms. Exposure to environmental or cell-intrinisic reactive oxygen species (ROS) can affect several components involved in Ca(2+) homeostasis and thus alter multiple pathways. While all cells have a capacity to produce intracellular ROS, exposure of immune and skin cells to extracellular oxidative stress is particularly high during inflammation and/or with UV exposure. This review briefly summarizes cell-intrinsic sources of ROS and focuses on current findings and controversies regarding the regulation of STIM and Orai by oxidative modifications. We also introduce melanocytes as a new model system to study the function of STIM and Orai isoforms under physiological conditions that include exposure to UV light as an activating stimulus.
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Affiliation(s)
- Ivan Bogeski
- Department of Biophysics, Saarland University, 66421 Homburg, Germany
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41
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Stanisz H, Stark A, Kilch T, Schwarz EC, Müller CSL, Peinelt C, Hoth M, Niemeyer BA, Vogt T, Bogeski I. ORAI1 Ca(2+) channels control endothelin-1-induced mitogenesis and melanogenesis in primary human melanocytes. J Invest Dermatol 2012; 132:1443-51. [PMID: 22318387 DOI: 10.1038/jid.2011.478] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
UV radiation of the skin triggers keratinocytes to secrete endothelin-1 (ET-1) that binds to endothelin receptors on neighboring melanocytes. Melanocytes respond with a prolonged increase in intracellular Ca(2+) concentration ([Ca(2+)](i)), which is necessary for proliferation and melanogenesis. A major fraction of the Ca(2+) signal is caused by entry through Ca(2+)-permeable channels of unknown identity in the plasma membrane. ORAI Ca(2+) channels are molecular determinants of Ca(2+) release-activated Ca(2+) (CRAC) channels and are expressed in many tissues. Here, we show that ORAI1-3 and their activating partners stromal interaction molecules 1 and 2 (STIM1 and STIM2) are expressed in human melanocytes. Although ORAI1 is the predominant ORAI isoform, STIM2 mRNA expression exceeds STIM1. Inhibition of ORAI1 by 2-aminoethoxydiphenyl borate (2-APB) or downregulation of ORAI1 by small interfering RNA (siRNA) reduced Ca(2+) entry and CRAC current amplitudes in activated melanocytes. In addition, suppression of ORAI1 caused reduction in the ET-1-induced cellular viability, melanin synthesis, and tyrosinase activity. Our results imply a role for ORAI1 channels in skin pigmentation and their potential involvement in UV-induced stress responses of the human skin.
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Affiliation(s)
- Hedwig Stanisz
- Department of Dermatology, Venerology and Allergology, University Hospital of the Saarland, Homburg, Germany.
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42
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Bogeski I, Al-Ansary D, Qu B, Niemeyer BA, Hoth M, Peinelt C. Pharmacology of ORAI channels as a tool to understand their physiological functions. Expert Rev Clin Pharmacol 2012; 3:291-303. [PMID: 22111611 DOI: 10.1586/ecp.10.23] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Store-operated Ca(2+) entry is a major Ca(2+) entry mechanism that is present in most cell types. In immune cells, store-operated Ca(2+) entry is almost exclusively mediated by Ca(2+) release-activated Ca(2+) (CRAC) channels. Ca(2+) entry through these channels and the corresponding cytosolic Ca(2+) signals are required for many immune cell functions, including all aspects of T-cell activation. ORAI proteins are the molecular correlates for the CRAC channels. The three human members, ORAI1, ORAI2 and ORAI3, are activated through the stromal interaction molecules (STIM)1 and 2 following depletion of endoplasmic reticulum Ca(2+) stores. Different combinations of STIM and ORAI can form different CRAC channels with distinct biophysical properties. In this article, we review and discuss mechanistic and functional implications of two important CRAC/ORAI inhibitors, 2-APB and BTP2, and the antibiotic G418 that has also been reported to interfere with ORAI channel function. The use of pharmacological tools should help to assign distinct physiological and pathophysiological functions to different STIM-ORAI protein complexes.
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Affiliation(s)
- Ivan Bogeski
- Department of Biophysics, Saarland University, Homburg, Germany
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43
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Kilch T, Al-Ansary D, Rychkov G, Peinelt C, Niemeyer BA. STIM1 Mutants Modify CRAC by Altering Orai1 Protein Concentration. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.3700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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44
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Bogeski I, Kappl R, Kummerow C, Gulaboski R, Hoth M, Niemeyer BA. Redox regulation of calcium ion channels: Chemical and physiological aspects. Cell Calcium 2011; 50:407-23. [DOI: 10.1016/j.ceca.2011.07.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 07/26/2011] [Indexed: 02/07/2023]
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45
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Bogeski I, Kummerow C, Al-Ansary D, Schwarz EC, Koehler R, Kozai D, Takahashi N, Peinelt C, Griesemer D, Bozem M, Mori Y, Hoth M, Niemeyer BA. Differential redox regulation of ORAI ion channels: a mechanism to tune cellular calcium signaling. Sci Signal 2010; 3:ra24. [PMID: 20354224 DOI: 10.1126/scisignal.2000672] [Citation(s) in RCA: 192] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Reactive oxygen species (ROS) are involved in many physiological and pathophysiological cellular processes. We used lymphocytes, which are exposed to highly oxidizing environments during inflammation, to study the influence of ROS on cellular function. Calcium ion (Ca(2+)) influx through Ca(2+) release-activated Ca(2+) (CRAC) channels composed of proteins of the ORAI family is essential for the activation, proliferation, and differentiation of T lymphocytes, but whether and how ROS affect ORAI channel function have been unclear. Here, we combined Ca(2+) imaging, patch-clamp recordings, and measurements of cell proliferation and cytokine secretion to determine the effects of hydrogen peroxide (H(2)O(2)) on ORAI channel activity and human T helper lymphocyte (T(H) cell) function. ORAI1, but not ORAI3, channels were inhibited by oxidation by H(2)O(2). The differential redox sensitivity of ORAI1 and ORAI3 channels depended mainly on an extracellularly located reactive cysteine, which is absent in ORAI3. T(H) cells became progressively less redox-sensitive after differentiation into effector cells, a shift that would allow them to proliferate, differentiate, and secrete cytokines in oxidizing environments. The decreased redox sensitivity of effector T(H) cells correlated with increased expression of Orai3 and increased abundance of several cytosolic antioxidants. Knockdown of ORAI3 with small-interfering RNA rendered effector T(H) cells more redox-sensitive. The differential expression of Orai isoforms between naïve and effector T(H) cells may tune cellular responses under oxidative stress.
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Affiliation(s)
- Ivan Bogeski
- Department of Biophysics, Saarland University, 66421 Homburg, Germany.
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46
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Al-Ansary D, Bogeski I, Disteldorf BMJ, Becherer U, Niemeyer BA. ATP modulates Ca2+ uptake by TRPV6 and is counteracted by isoform-specific phosphorylation. FASEB J 2009; 24:425-35. [PMID: 19805577 DOI: 10.1096/fj.09-141481] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ca(2+) homeostasis requires balanced uptake and extrusion, and dysregulation leads to disease. TRPV6 channels are homeostasis regulators, are upregulated in certain cancers, and show an unusual allele-specific evolution in humans. To understand how Ca(2+) uptake can be adapted to changes in metabolic status, we investigate regulation of Ca(2+)-influx by ATP and phosphorylation. We show that ATP binds to TRPV6, reduces whole-cell current increments, and prevents channel rundown with an EC(50) of 380 microM. By using both biochemical binding studies and patch-clamp analyses of wild-type and mutant channels, we have mapped one relevant site for regulation by ATP to residues within the ankyrin repeat domain (ARD) and identify an additional C-terminal binding region. Stimulation of PKC largely prevented the effects of ATP. This regulation requires PKC(betaII) and defined phosphorylation sites within the ARD and the C-terminus. Both regulatory sites act synergistically to constitute a novel mechanism by which ATP stabilizes channel activity and acts as a metabolic switch for Ca(2+) influx. Decreases in ATP concentration or activation of PKC(betaII) disable regulation of the channels by ATP, rendering them more susceptible to inactivation and rundown and preventing Ca(2+) overload.
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Affiliation(s)
- Dalia Al-Ansary
- Department of Pharmacology and Toxicology, University of Saarland, 66421 Homburg, Germany
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47
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Al-Ansary D, Becherer U, Flockerzi V, Niemeyer BA. PKCßII-Specific Phosphorylation Counteracts Regulation Of Trpv6 By ATP And Points Towards A Functional Difference Between Its Polymorphic Alleles. Biophys J 2009. [DOI: 10.1016/j.bpj.2008.12.2921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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48
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Abstract
The ion channel TRPV6 is likely to function as an epithelial calcium channel in organs with high calcium transport requirements such as the intestine, kidney, and placenta. Transcriptional regulation of TRPV6 messenger RNA (mRNA) is controlled by 1,25-dihydroxyvitamin D, which is the active hormonal form of vitamin D3, and by additional calcium-dependent and vitamin D3-independent mechanisms. Under physiological conditions, the conductance of the channel itself is highly calcium-selective and underlies complex inactivation mechanisms triggered by intracellular calcium and magnesium ions. There is growing evidence that transcriptional regulation of TRPV6 in certain tissues undergoing malignant transformation, such as prostate cancer, is linked to cancer progression.
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Affiliation(s)
- U Wissenbach
- Experimentelle und Klinische Pharmakologie und Toxikologie, Medizinische Fakultät, Universität des Saarlandes, 66421 Homburg, Germany.
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49
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Abstract
TRPM (transient receptor potential melastatin-like) channels are distinct from many other members of the transient receptor potential family in regard to their overall size (>1000 amino acids), the lack of N-terminal ankyrin-like repeats, and hydrophobicity predictions that may allow for more than six transmembrane regions. Common to each TRPM member is a prominent C-terminal coiled coil region. Here we have shown that TRPM8 channels assemble as multimers using the putative coiled coil region within the intracellular C terminus and that this assembly can be disturbed by a single point mutation within the coiled coil region. This mutant neither gives rise to functional channels nor do its subunits interact or form protein complexes that correspond to a multimer. However, they are still transported to the plasma membrane. Furthermore, wild-type currents can be suppressed by expressing the membrane-attached C-terminal region of TRPM8. To separate assembly from trafficking, we investigated the maturation of TRPM8 protein by identifying and mutating the relevant N-linked glycosylation site and showing that glycosylation is neither essential for multimerization nor for transport to the plasma membrane per se but appears to facilitate efficient multimerization and transport.
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Affiliation(s)
- Isabell Erler
- Department of Pharmacology and Toxicology, University of Saarland, Medical Campus, 66421 Homburg, Germany
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50
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Schwarz EC, Wissenbach U, Niemeyer BA, Strauss B, Philipp SE, Flockerzi V, Hoth M. TRPV6 potentiates calcium-dependent cell proliferation. Cell Calcium 2005; 39:163-73. [PMID: 16356545 DOI: 10.1016/j.ceca.2005.10.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 10/13/2005] [Accepted: 10/17/2005] [Indexed: 12/20/2022]
Abstract
The Ca(2+) homeostasis within cells controls a diversity of cellular processes including gene transcription, proliferation and apoptosis. Perturbance of Ca(2+) signaling may induce deregulation of cell proliferation and suppression of cell death providing the basis for cancer development. In human prostate cancer, a correlation between the mRNA expression of the Ca(2+) channel TRPV6 and the staging of the cancer has been described. We have analyzed the influence of TRPV6 on cell proliferation within HEK-293 cells. We show that TRPV6 increases cell proliferation of HEK-293 cells in a Ca(2+) dependent manner. The increased proliferation correlates with slightly increased intracellular Ca(2+) levels without interfering with the intrinsic Ca(2+) dependence of HEK-293 cell proliferation. Low doses of econazole inhibit both, TRPV6 dependent Ca(2+) signals and cell proliferation while BTP2, a potent inhibitor of Ca(2+) signals and cell proliferation in T-cells, neither influences TRPV6 dependent Ca(2+) signals nor cell proliferation of HEK-293 cells. Our data demonstrate that TRPV6 increases the rate of Ca(2+) dependent cell proliferation which is a prerequisite for its potential role in tumor progression.
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Affiliation(s)
- Eva C Schwarz
- Department of Physiology, University of the Saarland, Homburg, Germany.
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