1
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Tsvilovskyy V, Ottenheijm R, Kriebs U, Schütz A, Diakopoulos KN, Jha A, Bildl W, Wirth A, Böck J, Jaślan D, Ferro I, Taberner FJ, Kalinina O, Hildebrand S, Wissenbach U, Weissgerber P, Vogt D, Eberhagen C, Mannebach S, Berlin M, Kuryshev V, Schumacher D, Philippaert K, Camacho-Londoño JE, Mathar I, Dieterich C, Klugbauer N, Biel M, Wahl-Schott C, Lipp P, Flockerzi V, Zischka H, Algül H, Lechner SG, Lesina M, Grimm C, Fakler B, Schulte U, Muallem S, Freichel M. OCaR1 endows exocytic vesicles with autoregulatory competence by preventing uncontrolled Ca2+ release, exocytosis, and pancreatic tissue damage. J Clin Invest 2024; 134:e169428. [PMID: 38557489 PMCID: PMC10977991 DOI: 10.1172/jci169428] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 02/13/2024] [Indexed: 04/04/2024] Open
Abstract
Regulated exocytosis is initiated by increased Ca2+ concentrations in close spatial proximity to secretory granules, which is effectively prevented when the cell is at rest. Here we showed that exocytosis of zymogen granules in acinar cells was driven by Ca2+ directly released from acidic Ca2+ stores including secretory granules through NAADP-activated two-pore channels (TPCs). We identified OCaR1 (encoded by Tmem63a) as an organellar Ca2+ regulator protein integral to the membrane of secretory granules that controlled Ca2+ release via inhibition of TPC1 and TPC2 currents. Deletion of OCaR1 led to extensive Ca2+ release from NAADP-responsive granules under basal conditions as well as upon stimulation of GPCR receptors. Moreover, OCaR1 deletion exacerbated the disease phenotype in murine models of severe and chronic pancreatitis. Our findings showed OCaR1 as a gatekeeper of Ca2+ release that endows NAADP-sensitive secretory granules with an autoregulatory mechanism preventing uncontrolled exocytosis and pancreatic tissue damage.
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Affiliation(s)
- Volodymyr Tsvilovskyy
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | - Roger Ottenheijm
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | - Ulrich Kriebs
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Aline Schütz
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Kalliope Nina Diakopoulos
- Comprehensive Cancer Center München, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Archana Jha
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, USA
| | - Wolfgang Bildl
- Institute for Physiology, University of Freiburg, Freiburg, Germany
| | - Angela Wirth
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | - Julia Böck
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Dawid Jaślan
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Irene Ferro
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Francisco J. Taberner
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández–Consejo Superior de Investigaciones Científicas, Sant Joan d’Alacant, Spain
| | - Olga Kalinina
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Saarbrücken, Germany
| | - Staffan Hildebrand
- Institut für Pharmakologie und Toxikologie, Universität Bonn, Bonn, Germany
| | - Ulrich Wissenbach
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Homburg, Germany
| | - Petra Weissgerber
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Homburg, Germany
| | - Dominik Vogt
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Carola Eberhagen
- Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany
| | - Stefanie Mannebach
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Homburg, Germany
| | - Michael Berlin
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | - Vladimir Kuryshev
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Dagmar Schumacher
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Koenraad Philippaert
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Heidelberg, Germany
| | | | - Ilka Mathar
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Christoph Dieterich
- University Hospital Heidelberg, Department of Medicine III: Cardiology, Angiology and Pneumology, Heidelberg, Germany
| | - Norbert Klugbauer
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Fakultät für Medizin, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, and DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany
| | - Christian Wahl-Schott
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Medical Faculty, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Peter Lipp
- Institute for Molecular Cell Biology, Center for Molecular Signaling (PZMS), Universität des Saarlandes, Homburg, Germany
| | - Veit Flockerzi
- Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, Homburg, Germany
| | - Hans Zischka
- Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany
- Institute of Toxicology and Environmental Hygiene, Technical University Munich, School of Medicine, Munich, Germany
| | - Hana Algül
- Comprehensive Cancer Center München, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Stefan G. Lechner
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
| | - Marina Lesina
- Comprehensive Cancer Center München, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Christian Grimm
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, Munich, Germany
- Immunology, Infection and Pandemic Research (IIP), Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Munich, Germany
| | - Bernd Fakler
- Institute for Physiology, University of Freiburg, Freiburg, Germany
| | - Uwe Schulte
- Institute for Physiology, University of Freiburg, Freiburg, Germany
| | - Shmuel Muallem
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, USA
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany
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2
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Pruenster M, Immler R, Roth J, Kuchler T, Bromberger T, Napoli M, Nussbaumer K, Rohwedder I, Wackerbarth LM, Piantoni C, Hennis K, Fink D, Kallabis S, Schroll T, Masgrau-Alsina S, Budke A, Liu W, Vestweber D, Wahl-Schott C, Roth J, Meissner F, Moser M, Vogl T, Hornung V, Broz P, Sperandio M. E-selectin-mediated rapid NLRP3 inflammasome activation regulates S100A8/S100A9 release from neutrophils via transient gasdermin D pore formation. Nat Immunol 2023; 24:2021-2031. [PMID: 37903858 PMCID: PMC10681899 DOI: 10.1038/s41590-023-01656-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 09/18/2023] [Indexed: 11/01/2023]
Abstract
S100A8/S100A9 is a proinflammatory mediator released by myeloid cells during many acute and chronic inflammatory disorders. However, the precise mechanism of its release from the cytosolic compartment of neutrophils is unclear. Here, we show that E-selectin-induced rapid S100A8/S100A9 release during inflammation occurs in an NLRP3 inflammasome-dependent fashion. Mechanistically, E-selectin engagement triggers Bruton's tyrosine kinase-dependent tyrosine phosphorylation of NLRP3. Concomitant potassium efflux via the voltage-gated potassium channel KV1.3 mediates ASC oligomerization. This is followed by caspase 1 cleavage and downstream activation of pore-forming gasdermin D, enabling cytosolic release of S100A8/S100A9. Strikingly, E-selectin-mediated gasdermin D pore formation does not result in cell death but is a transient process involving activation of the ESCRT III membrane repair machinery. These data clarify molecular mechanisms of controlled S100A8/S100A9 release from neutrophils and identify the NLRP3/gasdermin D axis as a rapid and reversible activation system in neutrophils during inflammation.
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Affiliation(s)
- Monika Pruenster
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Roland Immler
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Jonas Roth
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Tim Kuchler
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Thomas Bromberger
- Institute of Experimental Hematology, School of Medicine, Technical University Munich, Munich, Germany
| | - Matteo Napoli
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Katrin Nussbaumer
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Ina Rohwedder
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Lou Martha Wackerbarth
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Chiara Piantoni
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Konstantin Hennis
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Diana Fink
- Department of Systems Immunology and Proteomics, Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Sebastian Kallabis
- Department of Systems Immunology and Proteomics, Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Tobias Schroll
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Sergi Masgrau-Alsina
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Agnes Budke
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Wang Liu
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Dietmar Vestweber
- Max Planck Institute for Molecular Biomedicine, Münster, Münster, Germany
| | - Christian Wahl-Schott
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Johannes Roth
- Institute of Immunology, University of Münster, Münster, Germany
| | - Felix Meissner
- Department of Systems Immunology and Proteomics, Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Markus Moser
- Institute of Experimental Hematology, School of Medicine, Technical University Munich, Munich, Germany
| | - Thomas Vogl
- Institute of Immunology, University of Münster, Münster, Germany
| | - Veit Hornung
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Petr Broz
- Department of Immunobiology, University of Lausanne, Epalinges, Switzerland
| | - Markus Sperandio
- Walter Brendel Centre of Experimental Medicine, Biomedical Center, Institute of Cardiovascular Physiology and Pathophysiology, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany.
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3
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Feldmann C, Schänzler M, Ben-Johny M, Wahl-Schott C. Protocol for deriving proximity, affinity, and stoichiometry of protein interactions using image-based quantitative two-hybrid FRET. STAR Protoc 2023; 4:102459. [PMID: 37516972 PMCID: PMC10400964 DOI: 10.1016/j.xpro.2023.102459] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/26/2023] [Accepted: 06/22/2023] [Indexed: 08/01/2023] Open
Abstract
Two-hybrid Förster resonance energy transfer (FRET) provides proximity, affinity, and stoichiometry information in binding interactions. We present an image-based approach that surpasses traditional two-hybrid FRET assays in precision and robustness. We outline instrument setup and image acquisition and further describe steps for image preprocessing and two-hybrid FRET analysis using provided software to simplify the workflow. This protocol is compatible with confocal microscopes for high-precision and imaging plate readers for high-throughput applications. A plasmid-based reference system supports fast establishment of the protocol. For complete details on the use and execution of this protocol, please refer to Rivas et al.1.
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Affiliation(s)
- Colin Feldmann
- Institute of Cardiovascular Physiology and Pathophysiology, Faculty of Medicine, Biomedical Center, LMU-Munich, 82152 Planegg-Martinsried, Germany; Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Michael Schänzler
- Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany
| | - Manu Ben-Johny
- Department of Physiology and Cellular Biophysics, Columbia University, Medical Center, New York 10032, NY, USA
| | - Christian Wahl-Schott
- Institute of Cardiovascular Physiology and Pathophysiology, Faculty of Medicine, Biomedical Center, LMU-Munich, 82152 Planegg-Martinsried, Germany; Institute of Neurophysiology, Medizinische Hochschule Hannover, 30625 Hannover, Germany.
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4
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Wahl-Schott C, Freichel M, Hennis K, Philippaert K, Ottenheijm R, Tsvilovskyy V, Varbanov H. Characterization of Endo-Lysosomal Cation Channels Using Calcium Imaging. Handb Exp Pharmacol 2023; 278:277-304. [PMID: 36894791 DOI: 10.1007/164_2023_637] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Endo-lysosomes are membrane-bound acidic organelles that are involved in endocytosis, recycling, and degradation of extracellular and intracellular material. The membranes of endo-lysosomes express several Ca2+-permeable cation ion channels, including two-pore channels (TPC1-3) and transient receptor potential mucolipin channels (TRPML1-3). In this chapter, we will describe four different state-of-the-art Ca2+ imaging approaches, which are well-suited to investigate the function of endo-lysosomal cation channels. These techniques include (1) global cytosolic Ca2+ measurements, (2) peri-endo-lysosomal Ca2+ imaging using genetically encoded Ca2+ sensors that are directed to the cytosolic endo-lysosomal membrane surface, (3) Ca2+ imaging of endo-lysosomal cation channels, which are engineered in order to redirect them to the plasma membrane in combination with approaches 1 and 2, and (4) Ca2+ imaging by directing Ca2+ indicators to the endo-lysosomal lumen. Moreover, we will review useful small molecules, which can be used as valuable tools for endo-lysosomal Ca2+ imaging. Rather than providing complete protocols, we will discuss specific methodological issues related to endo-lysosomal Ca2+ imaging.
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Affiliation(s)
- Christian Wahl-Schott
- Institut für Kardiovaskuläre Physiologie und Pathophysiologie, Lehrstuhl für Vegetative Physiologie, Biomedizinisches Zentrum, Ludwig-Maximilians-Universität München, München, Germany.
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany. .,DZHK (German Centre for Cardiovascular Research), Heidelberg/Mannheim, Germany.
| | - Konstantin Hennis
- Institut für Kardiovaskuläre Physiologie und Pathophysiologie, Lehrstuhl für Vegetative Physiologie, Biomedizinisches Zentrum, Ludwig-Maximilians-Universität München, München, Germany
| | - Koenraad Philippaert
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Heidelberg/Mannheim, Germany
| | - Roger Ottenheijm
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Heidelberg/Mannheim, Germany
| | - Volodymyr Tsvilovskyy
- Institute of Pharmacology, Heidelberg University, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Heidelberg/Mannheim, Germany
| | - Hristo Varbanov
- Institut für Neurophysiologie, Medizinische Hochschule Hannover(MHH), Hannover, Germany
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5
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Berlin M, Londoño JEC, Ottenheijm R, Kraft A, Bacmeister L, Tsvilovskyy V, Meyer S, Hennis K, Gerndt S, Offen K, Leuschner F, Bracher F, Fenske S, Biel M, Hansen A, Grimm C, Wahl-Schott C, Freichel M. An endo-lysosomal Ca2+ store in cardiomyocytes controlled by OCaR proteins determines fatal tachyarrhythmias. J Mol Cell Cardiol 2022. [DOI: 10.1016/j.yjmcc.2022.08.058] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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6
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Scotto Rosato A, Krogsaeter EK, Jaślan D, Abrahamian C, Montefusco S, Soldati C, Spix B, Pizzo MT, Grieco G, Böck J, Wyatt A, Wünkhaus D, Passon M, Stieglitz M, Keller M, Hermey G, Markmann S, Gruber-Schoffnegger D, Cotman S, Johannes L, Crusius D, Boehm U, Wahl-Schott C, Biel M, Bracher F, De Leonibus E, Polishchuk E, Medina DL, Paquet D, Grimm C. TPC2 rescues lysosomal storage in mucolipidosis type IV, Niemann-Pick type C1, and Batten disease. EMBO Mol Med 2022; 14:e15377. [PMID: 35929194 PMCID: PMC9449600 DOI: 10.15252/emmm.202115377] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [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: 11/03/2021] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 01/05/2023] Open
Abstract
Lysosomes are cell organelles that degrade macromolecules to recycle their components. If lysosomal degradative function is impaired, e.g., due to mutations in lysosomal enzymes or membrane proteins, lysosomal storage diseases (LSDs) can develop. LSDs manifest often with neurodegenerative symptoms, typically starting in early childhood, and going along with a strongly reduced life expectancy and quality of life. We show here that small molecule activation of the Ca2+‐permeable endolysosomal two‐pore channel 2 (TPC2) results in an amelioration of cellular phenotypes associated with LSDs such as cholesterol or lipofuscin accumulation, or the formation of abnormal vacuoles seen by electron microscopy. Rescue effects by TPC2 activation, which promotes lysosomal exocytosis and autophagy, were assessed in mucolipidosis type IV (MLIV), Niemann–Pick type C1, and Batten disease patient fibroblasts, and in neurons derived from newly generated isogenic human iPSC models for MLIV and Batten disease. For in vivo proof of concept, we tested TPC2 activation in the MLIV mouse model. In sum, our data suggest that TPC2 is a promising target for the treatment of different types of LSDs, both in vitro and in‐vivo.
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Affiliation(s)
- Anna Scotto Rosato
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Einar K Krogsaeter
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Dawid Jaślan
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Carla Abrahamian
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | | | - Chiara Soldati
- Telethon Institute of Genetics and Medicine, Naples, Italy
| | - Barbara Spix
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | | | | | - Julia Böck
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Amanda Wyatt
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | | | - Marcel Passon
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Marc Stieglitz
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Marco Keller
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Guido Hermey
- Center for Molecular Neurobiology Hamburg (ZMNH), Institute of Molecular and Cellular Cognition, UKE, Hamburg, Germany
| | | | | | - Susan Cotman
- Department of Neurology, Center for Genomic Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ludger Johannes
- Cellular and Chemical Biology Department, Institut Curie, U1143 INSERM, UMR3666 CNRS, PSL Research University, Paris, France
| | - Dennis Crusius
- Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Hospital, Munich, Germany
| | - Ulrich Boehm
- Experimental Pharmacology, Center for Molecular Signaling (PZMS), Saarland University School of Medicine, Homburg, Germany
| | | | - Martin Biel
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Franz Bracher
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Elvira De Leonibus
- Telethon Institute of Genetics and Medicine, Naples, Italy.,Institute of Biochemistry and Cell Biology (IBBC), CNR, Rome, Italy
| | | | - Diego L Medina
- Telethon Institute of Genetics and Medicine, Naples, Italy.,Medical Genetics Unit, Department of Medical and Translational Science, Federico II University, Naples, Italy
| | - Dominik Paquet
- Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Hospital, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Christian Grimm
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität, Munich, Germany
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7
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Hennis K, Rötzer RD, Rilling J, Wu Y, Thalhammer SB, Biel M, Wahl-Schott C, Fenske S. In vivo and ex vivo electrophysiological study of the mouse heart to characterize the cardiac conduction system, including atrial and ventricular vulnerability. Nat Protoc 2022; 17:1189-1222. [PMID: 35314849 DOI: 10.1038/s41596-021-00678-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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: 09/27/2021] [Accepted: 12/09/2021] [Indexed: 01/05/2023]
Abstract
The mouse is a common and cost-effective animal model for basic research, and the number of genetically engineered mouse models with cardiac phenotype is increasing. In vivo electrophysiological study in mice is similar to that performed in humans. It is indispensable for acquiring intracardiac electrocardiogram recordings and determining baseline cardiac cycle intervals. Furthermore, the use of programmed electrical stimulation enables determination of parameters such as sinoatrial conduction time, sinus node recovery time, atrioventricular-nodal conduction properties, Wenckebach periodicity, refractory periods and arrhythmia vulnerability. This protocol describes specific procedures for determining these parameters that were adapted from analogous human protocols for use in mice. We include details of ex vivo electrophysiological study, which provides detailed insights into intrinsic cardiac electrophysiology without external influences from humoral and neural factors. In addition, we describe a heart preparation with intact innervation by the vagus nerve that can be used as an ex vivo model for vagal control of the cardiac conduction system. Data acquisition for in vivo and ex vivo electrophysiological study takes ~1 h per mouse, depending on the number of stimulation protocols applied during the procedure. The technique yields highly reliable results and can be used for phenotyping of cardiac disease models, elucidating disease mechanisms and confirming functional improvements in gene therapy approaches as well as for drug and toxicity testing.
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Affiliation(s)
- Konstantin Hennis
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - René D Rötzer
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Julia Rilling
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Yakun Wu
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stefan B Thalhammer
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
| | - Martin Biel
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany
| | | | - Stefanie Fenske
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany.
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, Germany.
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8
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Spix B, Butz ES, Chen CC, Rosato AS, Tang R, Jeridi A, Kudrina V, Plesch E, Wartenberg P, Arlt E, Briukhovetska D, Ansari M, Günsel GG, Conlon TM, Wyatt A, Wetzel S, Teupser D, Holdt LM, Ectors F, Boekhoff I, Boehm U, García-Añoveros J, Saftig P, Giera M, Kobold S, Schiller HB, Zierler S, Gudermann T, Wahl-Schott C, Bracher F, Yildirim AÖ, Biel M, Grimm C. Lung emphysema and impaired macrophage elastase clearance in mucolipin 3 deficient mice. Nat Commun 2022; 13:318. [PMID: 35031603 PMCID: PMC8760276 DOI: 10.1038/s41467-021-27860-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [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: 03/17/2021] [Accepted: 12/16/2021] [Indexed: 02/06/2023] Open
Abstract
Lung emphysema and chronic bronchitis are the two most common causes of chronic obstructive pulmonary disease. Excess macrophage elastase MMP-12, which is predominantly secreted from alveolar macrophages, is known to mediate the development of lung injury and emphysema. Here, we discovered the endolysosomal cation channel mucolipin 3 (TRPML3) as a regulator of MMP-12 reuptake from broncho-alveolar fluid, driving in two independently generated Trpml3-/- mouse models enlarged lung injury, which is further exacerbated after elastase or tobacco smoke treatment. Mechanistically, using a Trpml3IRES-Cre/eR26-τGFP reporter mouse model, transcriptomics, and endolysosomal patch-clamp experiments, we show that in the lung TRPML3 is almost exclusively expressed in alveolar macrophages, where its loss leads to defects in early endosomal trafficking and endocytosis of MMP-12. Our findings suggest that TRPML3 represents a key regulator of MMP-12 clearance by alveolar macrophages and may serve as therapeutic target for emphysema and chronic obstructive pulmonary disease.
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Affiliation(s)
- Barbara Spix
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Elisabeth S Butz
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
- Institute for Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
- Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Anna Scotto Rosato
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Rachel Tang
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Aicha Jeridi
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Veronika Kudrina
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Eva Plesch
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Philipp Wartenberg
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Daria Briukhovetska
- Division of Clinical Pharmacology, Department of Medicine IV, University Hospital Munich, Munich, Germany
| | - Meshal Ansari
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Gizem Günes Günsel
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Thomas M Conlon
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Amanda Wyatt
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Sandra Wetzel
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Daniel Teupser
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Lesca M Holdt
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Fabien Ectors
- FARAH Mammalian Transgenics Platform, Liège University, Liège, Belgium
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Ulrich Boehm
- Saarland University, Center for Molecular Signaling (PZMS), Experimental Pharmacology, Homburg, Germany
| | - Jaime García-Añoveros
- Departments of Anesthesiology, Physiology and Neurology, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Paul Saftig
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Martin Giera
- Center for Proteomics and Metabolomics, Leiden University Medical Center, 2333ZA, Leiden, The Netherlands
| | - Sebastian Kobold
- Division of Clinical Pharmacology, Department of Medicine IV, University Hospital Munich, Munich, Germany
- German Center for Translational Cancer Research (DKTK), partner site Munich, Munich, Germany
| | - Herbert B Schiller
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
- Institute of Pharmacology, Johannes-Keppler-University, Linz, Australia
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany
- German Center of Lung Research (DZL), Munich, Germany
| | | | - Franz Bracher
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany
| | - Ali Önder Yildirim
- Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL), Munich, Germany.
| | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-University, Munich, Germany.
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany.
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9
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Li Y, Schön C, Chen CC, Yang Z, Liegl R, Murenu E, Schworm B, Klugbauer N, Grimm C, Wahl-Schott C, Michalakis S, Biel M. TPC2 promotes choroidal angiogenesis and inflammation in a mouse model of neovascular age-related macular degeneration. Life Sci Alliance 2021; 4:4/8/e202101047. [PMID: 34183443 PMCID: PMC8321671 DOI: 10.26508/lsa.202101047] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 12/23/2022] Open
Abstract
This study identifies the endolysosomal two-pore channel TPC2 as a potential novel drug target for age-related macular degeneration (AMD). Inhibition of TPC2 reduces two key clinical hallmarks of the AMD, retinal inflammation and formation of leaky choroi. Age-related macular degeneration (AMD) is the most common cause of blindness among the elderly and can be classified either as dry or as neovascular (or wet). Neovascular AMD is characterized by a strong immune response and the inadequate release of cytokines triggering angiogenesis and induction of photoreceptor death. The pathomechanisms of AMD are only partly understood. Here, we identify the endolysosomal two-pore cation channel TPC2 as a key factor of neovascularization and immune activation in the laser-induced choroidal neovascularization (CNV) mouse model of AMD. Block of TPC2 reduced retinal VEGFA and IL-1β levels and diminished neovascularization and immune activation. Mechanistically, TPC2 mediates cationic currents in endolysosomal organelles of immune cells and lack of TPC2 leads to reduced IL-1β levels in areas of choroidal neovascularization due to endolysosomal trapping. Taken together, our study identifies TPC2 as a promising novel therapeutic target for the treatment of AMD.
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Affiliation(s)
- Yanfen Li
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Christian Schön
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany.,Department of Clinical Laboratory Sciences and Medical Biotechnology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Zhuo Yang
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Raffael Liegl
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Elisa Murenu
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
| | - Benedikt Schworm
- Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Norbert Klugbauer
- Institute for Experimental and Clinical Pharmacology and Toxicology, Medical Faculty, Albert-Ludwigs-University, Freiburg, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, München, Germany
| | | | - Stylianos Michalakis
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany .,Department of Ophthalmology, University Hospital, LMU Munich, München, Germany
| | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-Universität München, München, Germany
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10
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Hennis K, Rötzer RD, Piantoni C, Biel M, Wahl-Schott C, Fenske S. Speeding Up the Heart? Traditional and New Perspectives on HCN4 Function. Front Physiol 2021; 12:669029. [PMID: 34122140 PMCID: PMC8191466 DOI: 10.3389/fphys.2021.669029] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [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: 02/17/2021] [Accepted: 04/19/2021] [Indexed: 01/20/2023] Open
Abstract
The sinoatrial node (SAN) is the primary pacemaker of the heart and is responsible for generating the intrinsic heartbeat. Within the SAN, spontaneously active pacemaker cells initiate the electrical activity that causes the contraction of all cardiomyocytes. The firing rate of pacemaker cells depends on the slow diastolic depolarization (SDD) and determines the intrinsic heart rate (HR). To adapt cardiac output to varying physical demands, HR is regulated by the autonomic nervous system (ANS). The sympathetic and parasympathetic branches of the ANS innervate the SAN and regulate the firing rate of pacemaker cells by accelerating or decelerating SDD-a process well-known as the chronotropic effect. Although this process is of fundamental physiological relevance, it is still incompletely understood how it is mediated at the subcellular level. Over the past 20 years, most of the work to resolve the underlying cellular mechanisms has made use of genetically engineered mouse models. In this review, we focus on the findings from these mouse studies regarding the cellular mechanisms involved in the generation and regulation of the heartbeat, with particular focus on the highly debated role of the hyperpolarization-activated cyclic nucleotide-gated cation channel HCN4 in mediating the chronotropic effect. By focusing on experimental data obtained in mice and humans, but not in other species, we outline how findings obtained in mice relate to human physiology and pathophysiology and provide specific information on how dysfunction or loss of HCN4 channels leads to human SAN disease.
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Affiliation(s)
- Konstantin Hennis
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - René D. Rötzer
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Chiara Piantoni
- Institute for Neurophysiology, Hannover Medical School, Hanover, Germany
| | - Martin Biel
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Christian Wahl-Schott
- Institute for Neurophysiology, Hannover Medical School, Hanover, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Stefanie Fenske
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
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11
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Hennis K, Biel M, Wahl-Schott C, Fenske S. Beyond pacemaking: HCN channels in sinoatrial node function. Prog Biophys Mol Biol 2021; 166:51-60. [PMID: 33753086 DOI: 10.1016/j.pbiomolbio.2021.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/04/2021] [Accepted: 03/16/2021] [Indexed: 01/16/2023]
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are key proteins involved in the initiation and regulation of the heartbeat. Pacemaker cells within the sinoatrial node generate the electrical impulse that underlies the contraction of all atrial and ventricular cardiomyocytes. To generate a stable heart rhythm, it is necessary that the spontaneous activity of pacemaker cells is synchronized. Entrainment processes in the sinoatrial node create synchrony and also mediate heart rate regulation. In the past years it has become clear that the role of HCN channels goes beyond just pacemaking and that the channels play pivotal roles in these entrainment processes that coordinate and balance sinoatrial node network activity. Here, we review the role of HCN channels in the central pacemaker process and highlight new aspects of the contribution of HCN channels to stabilizing the electrical activity of the sinoatrial node network, especially during heart rate regulation by the autonomic nervous system.
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Affiliation(s)
- Konstantin Hennis
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany
| | - Martin Biel
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany
| | - Christian Wahl-Schott
- Hannover Medical School, Institute for Neurophysiology, 30625, Hannover, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany.
| | - Stefanie Fenske
- Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377, Munich, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, 80802, Munich, Germany.
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12
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Rötzer RD, Brox VF, Hennis K, Thalhammer SB, Biel M, Wahl-Schott C, Fenske S. Implantation of Combined Telemetric ECG and Blood Pressure Transmitters to Determine Spontaneous Baroreflex Sensitivity in Conscious Mice. J Vis Exp 2021. [PMID: 33645573 DOI: 10.3791/62101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 10/31/2022] Open
Abstract
Blood pressure (BP) and heart rate (HR) are both controlled by the autonomic nervous system (ANS) and are closely intertwined due to reflex mechanisms. The baroreflex is a key homeostatic mechanism to counteract acute, short-term changes in arterial BP and to maintain BP in a relatively narrow physiological range. BP is sensed by baroreceptors located in the aortic arch and carotid sinus. When BP changes, signals are transmitted to the central nervous system and are then communicated to the parasympathetic and sympathetic branches of the autonomic nervous system to adjust HR. A rise in BP causes a reflex decrease in HR, a drop in BP causes a reflex increase in HR. Baroreflex sensitivity (BRS) is the quantitative relationship between changes in arterial BP and corresponding changes in HR. Cardiovascular diseases are often associated with impaired baroreflex function. In various studies reduced BRS has been reported in e.g., heart failure, myocardial infarction, or coronary artery disease. Determination of BRS requires information from both BP and HR, which can be recorded simultaneously using telemetric devices. The surgical procedure is described beginning with the insertion of the pressure sensor into the left carotid artery and positioning of its tip in the aortic arch to monitor arterial pressure followed by the subcutaneous placement of the transmitter and ECG electrodes. We also describe postoperative intensive care and analgesic management. After a two-week period of post-surgery recovery long-term ECG and BP recordings are performed in conscious and unrestrained mice. Finally, we include examples of high-quality recordings and the analysis of spontaneous baroreceptor sensitivity using the sequence method.
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Affiliation(s)
- René D Rötzer
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München
| | - Verena F Brox
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München
| | - Konstantin Hennis
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München
| | - Stefan B Thalhammer
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München
| | - Martin Biel
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance
| | | | - Stefanie Fenske
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München; German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance;
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13
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Drakhlis L, Biswanath S, Farr CM, Lupanow V, Teske J, Ritzenhoff K, Franke A, Manstein F, Bolesani E, Kempf H, Liebscher S, Schenke-Layland K, Hegermann J, Nolte L, Meyer H, de la Roche J, Thiemann S, Wahl-Schott C, Martin U, Zweigerdt R. Human heart-forming organoids recapitulate early heart and foregut development. Nat Biotechnol 2021; 39:737-746. [PMID: 33558697 PMCID: PMC8192303 DOI: 10.1038/s41587-021-00815-9] [Citation(s) in RCA: 143] [Impact Index Per Article: 47.7] [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: 06/18/2019] [Accepted: 12/30/2020] [Indexed: 12/13/2022]
Abstract
Organoid models of early tissue development have been produced for the intestine, brain, kidney and other organs, but similar approaches for the heart have been lacking. Here we generate complex, highly structured, three-dimensional heart-forming organoids (HFOs) by embedding human pluripotent stem cell aggregates in Matrigel followed by directed cardiac differentiation via biphasic WNT pathway modulation with small molecules. HFOs are composed of a myocardial layer lined by endocardial-like cells and surrounded by septum-transversum-like anlagen; they further contain spatially and molecularly distinct anterior versus posterior foregut endoderm tissues and a vascular network. The architecture of HFOs closely resembles aspects of early native heart anlagen before heart tube formation, which is known to require an interplay with foregut endoderm development. We apply HFOs to study genetic defects in vitro by demonstrating that NKX2.5-knockout HFOs show a phenotype reminiscent of cardiac malformations previously observed in transgenic mice. Heart-forming organoids model early cardiac development.
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Affiliation(s)
- Lika Drakhlis
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany.
| | - Santoshi Biswanath
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Clara-Milena Farr
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Victoria Lupanow
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Jana Teske
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Katharina Ritzenhoff
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Annika Franke
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Felix Manstein
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Emiliano Bolesani
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany
| | - Henning Kempf
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany.,Stem Cell Discovery, Novo Nordisk A/S, Måløv, Denmark
| | - Simone Liebscher
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Katja Schenke-Layland
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University Tübingen, Tübingen, Germany.,The Natural and Medical Sciences Institute (NMI) at the University of Tübingen, Reutlingen, Germany.,Department of Medicine/Cardiology, Cardiovascular Research Laboratories, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.,Cluster of Excellence iFIT (EXC 2180) 'Image-Guided and Functionally Instructed Tumor Therapies', Eberhard Karls University Tübingen, Tübingen, Germany
| | - Jan Hegermann
- Research Core Unit Electron Microscopy, Hannover Medical School, Hannover, Germany.,Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Lena Nolte
- Industrial and Biomedical Optics Department, Laser Zentrum Hannover, Hannover, Germany
| | - Heiko Meyer
- Industrial and Biomedical Optics Department, Laser Zentrum Hannover, Hannover, Germany
| | - Jeanne de la Roche
- Institute for Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Stefan Thiemann
- Institute for Neurophysiology, Hannover Medical School, Hannover, Germany
| | | | - Ulrich Martin
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
| | - Robert Zweigerdt
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Department of Cardiothoracic, Transplantation and Vascular Surgery (HTTG), REBIRTH-Research Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany.
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14
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Müller FE, Schade SK, Cherkas V, Stopper L, Breithausen B, Minge D, Varbanov H, Wahl-Schott C, Antoniuk S, Domingos C, Compan V, Kirchhoff F, Henneberger C, Ponimaskin E, Zeug A. Serotonin receptor 4 regulates hippocampal astrocyte morphology and function. Glia 2020; 69:872-889. [PMID: 33156956 DOI: 10.1002/glia.23933] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [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: 11/18/2019] [Revised: 10/15/2020] [Accepted: 10/19/2020] [Indexed: 12/25/2022]
Abstract
Astrocytes are an important component of the multipartite synapse and crucial for proper neuronal network function. Although small GTPases of the Rho family are powerful regulators of cellular morphology, the signaling modules of Rho-mediated pathways in astrocytes remain enigmatic. Here we demonstrated that the serotonin receptor 4 (5-HT4 R) is expressed in hippocampal astrocytes, both in vitro and in vivo. Through fluorescence microscopy, we established that 5-HT4 R activation triggered RhoA activity via Gα13 -mediated signaling, which boosted filamentous actin assembly, leading to morphological changes in hippocampal astrocytes. We investigated the effects of these 5-HT4 R-mediated changes in mixed cultures and in acute slices, in which 5-HT4 R was expressed exclusively in astrocytes. In both systems, 5-HT4 R-RhoA signaling changed glutamatergic synaptic transmission: It increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) in mixed cultures and reduced the paired-pulse-ratio (PPR) of field excitatory postsynaptic potentials (fEPSPs) in acute slices. Overall, our present findings demonstrate that astrocytic 5-HT4 R-Gα13 -RhoA signaling is a previously unrecognized molecular pathway involved in the functional regulation of excitatory synaptic circuits.
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Affiliation(s)
| | - Sophie K Schade
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Volodymyr Cherkas
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Laura Stopper
- Department of Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Björn Breithausen
- Institute of Cellular Neurosciences, Medical School, University of Bonn, Bonn, Germany
| | - Daniel Minge
- Institute of Cellular Neurosciences, Medical School, University of Bonn, Bonn, Germany
| | - Hristo Varbanov
- Institute of Neurophysiology, Hannover Medical School, Hannover, Germany
| | | | - Svitlana Antoniuk
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany.,Nencki Institute of Experimental Biology of the Polish Academy of Science, Warsaw, Poland
| | - Catia Domingos
- Institute of Cellular Neurosciences, Medical School, University of Bonn, Bonn, Germany
| | - Valérie Compan
- Department of Sciences, Brain, Anorexia & Addiction, Nîmes University, Nîmes, France
| | - Frank Kirchhoff
- Department of Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Christian Henneberger
- Institute of Cellular Neurosciences, Medical School, University of Bonn, Bonn, Germany.,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Institute of Neurology, University College London, London, UK
| | - Evgeni Ponimaskin
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany.,Institute of Neuroscience, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Andre Zeug
- Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
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15
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Chen CC, Krogsaeter E, Butz ES, Li Y, Puertollano R, Wahl-Schott C, Biel M, Grimm C. TRPML2 is an osmo/mechanosensitive cation channel in endolysosomal organelles. Sci Adv 2020; 6:6/46/eabb5064. [PMID: 33177082 PMCID: PMC7673730 DOI: 10.1126/sciadv.abb5064] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 09/24/2020] [Indexed: 05/12/2023]
Abstract
Endolysosomes are dynamic, intracellular compartments, regulating their surface-to-volume ratios to counteract membrane swelling or shrinkage caused by osmotic challenges upon tubulation and vesiculation events. While osmosensitivity has been extensively described on the plasma membrane, the mechanisms underlying endolysosomal surface-to-volume ratio changes and identities of involved ion channels remain elusive. Endolysosomes mediate endocytosis, exocytosis, cargo transport, and sorting of material for recycling or degradation. We demonstrate the endolysosomal cation channel TRPML2 to be hypotonicity/mechanosensitive, a feature crucial to its involvement in fast-recycling processes of immune cells. We demonstrate that the phosphoinositide binding pocket is required for TRPML2 hypotonicity-sensitivity, as substitution of L314 completely abrogates hypotonicity-sensitivity. Last, the hypotonicity-insensitive TRPML2 mutant L314R slows down the fast recycling pathway, corroborating the functional importance of hypotonicity-sensitive TRPML2. Our results highlight TRPML2 as an accelerator of endolysosomal trafficking by virtue of its hypotonicity-sensitivity, with implications in immune cell surveillance and viral trafficking.
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Affiliation(s)
- Cheng-Chang Chen
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.
| | - Einar Krogsaeter
- Walther Straub Institute of Pharmacology and Toxicology Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Elisabeth S Butz
- Center for Genomic Medicine, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Yanfen Li
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Rosa Puertollano
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | | | - Martin Biel
- Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany.
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16
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Böhm S, Splith V, Riedmayr LM, Rötzer RD, Gasparoni G, Nordström KJV, Wagner JE, Hinrichsmeyer KS, Walter J, Wahl-Schott C, Fenske S, Biel M, Michalakis S, Becirovic E. A gene therapy for inherited blindness using dCas9-VPR-mediated transcriptional activation. Sci Adv 2020; 6:eaba5614. [PMID: 32875106 PMCID: PMC7438099 DOI: 10.1126/sciadv.aba5614] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 07/08/2020] [Indexed: 05/08/2023]
Abstract
Catalytically inactive dCas9 fused to transcriptional activators (dCas9-VPR) enables activation of silent genes. Many disease genes have counterparts, which serve similar functions but are expressed in distinct cell types. One attractive option to compensate for the missing function of a defective gene could be to transcriptionally activate its functionally equivalent counterpart via dCas9-VPR. Key challenges of this approach include the delivery of dCas9-VPR, activation efficiency, long-term expression of the target gene, and adverse effects in vivo. Using dual adeno-associated viral vectors expressing split dCas9-VPR, we show efficient transcriptional activation and long-term expression of cone photoreceptor-specific M-opsin (Opn1mw) in a rhodopsin-deficient mouse model for retinitis pigmentosa. One year after treatment, this approach yields improved retinal function and attenuated retinal degeneration with no apparent adverse effects. Our study demonstrates that dCas9-VPR-mediated transcriptional activation of functionally equivalent genes has great potential for the treatment of genetic disorders.
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Affiliation(s)
- Sybille Böhm
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Victoria Splith
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Lisa Maria Riedmayr
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - René Dominik Rötzer
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Gilles Gasparoni
- Department of Genetics, Saarland University, Saarbrücken, Germany
| | | | - Johanna Elisabeth Wagner
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Klara Sonnie Hinrichsmeyer
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jörn Walter
- Department of Genetics, Saarland University, Saarbrücken, Germany
| | | | - Stefanie Fenske
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stylianos Michalakis
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
- Department of Ophthalmology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Elvir Becirovic
- Center for Integrated Protein Science Munich CIPSM, Munich, Germany
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
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17
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Arlt E, Fraticelli M, Tsvilovskyy V, Nadolni W, Breit A, O'Neill TJ, Resenberger S, Wennemuth G, Wahl-Schott C, Biel M, Grimm C, Freichel M, Gudermann T, Klugbauer N, Boekhoff I, Zierler S. TPC1 deficiency or blockade augments systemic anaphylaxis and mast cell activity. Proc Natl Acad Sci U S A 2020; 117:18068-18078. [PMID: 32661165 PMCID: PMC7395440 DOI: 10.1073/pnas.1920122117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mast cells and basophils are main drivers of allergic reactions and anaphylaxis, for which prevalence is rapidly increasing. Activation of these cells leads to a tightly controlled release of inflammatory mediators stored in secretory granules. The release of these granules is dependent on intracellular calcium (Ca2+) signals. Ca2+ release from endolysosomal compartments is mediated via intracellular cation channels, such as two-pore channel (TPC) proteins. Here, we uncover a mechanism for how TPC1 regulates Ca2+ homeostasis and exocytosis in mast cells in vivo and ex vivo. Notably, in vivo TPC1 deficiency in mice leads to enhanced passive systemic anaphylaxis, reflected by increased drop in body temperature, most likely due to accelerated histamine-induced vasodilation. Ex vivo, mast cell-mediated histamine release and degranulation was augmented upon TPC1 inhibition, although mast cell numbers and size were diminished. Our results indicate an essential role of TPC1 in endolysosomal Ca2+ uptake and filling of endoplasmic reticulum Ca2+ stores, thereby regulating exocytosis in mast cells. Thus, pharmacological modulation of TPC1 might blaze a trail to develop new drugs against mast cell-related diseases, including allergic hypersensitivity.
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Affiliation(s)
- Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Marco Fraticelli
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | | | - Wiebke Nadolni
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Andreas Breit
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Thomas J O'Neill
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Stefanie Resenberger
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Gunther Wennemuth
- Institute for Anatomy, University of Duisburg-Essen, 45147 Duisburg, Germany
| | | | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Marc Freichel
- Institute of Pharmacology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Norbert Klugbauer
- Institute for Experimental and Clinical Pharmacology and Toxicology, Medical Faculty, Albert-Ludwigs-Universität, 79104 Freiburg, Germany
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany;
| | - Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universität München, 80336 München, Germany;
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18
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Gerndt S, Chen CC, Chao YK, Yuan Y, Burgstaller S, Scotto Rosato A, Krogsaeter E, Urban N, Jacob K, Nguyen ONP, Miller MT, Keller M, Vollmar AM, Gudermann T, Zierler S, Schredelseker J, Schaefer M, Biel M, Malli R, Wahl-Schott C, Bracher F, Patel S, Grimm C. Agonist-mediated switching of ion selectivity in TPC2 differentially promotes lysosomal function. eLife 2020; 9:54712. [PMID: 32167471 PMCID: PMC7108868 DOI: 10.7554/elife.54712] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 03/12/2020] [Indexed: 12/16/2022] Open
Abstract
Ion selectivity is a defining feature of a given ion channel and is considered immutable. Here we show that ion selectivity of the lysosomal ion channel TPC2, which is hotly debated (Calcraft et al., 2009; Guo et al., 2017; Jha et al., 2014; Ruas et al., 2015; Wang et al., 2012), depends on the activating ligand. A high-throughput screen identified two structurally distinct TPC2 agonists. One of these evoked robust Ca2+-signals and non-selective cation currents, the other weaker Ca2+-signals and Na+-selective currents. These properties were mirrored by the Ca2+-mobilizing messenger, NAADP and the phosphoinositide, PI(3,5)P2, respectively. Agonist action was differentially inhibited by mutation of a single TPC2 residue and coupled to opposing changes in lysosomal pH and exocytosis. Our findings resolve conflicting reports on the permeability and gating properties of TPC2 and they establish a new paradigm whereby a single ion channel mediates distinct, functionally-relevant ionic signatures on demand.
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Affiliation(s)
- Susanne Gerndt
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.,Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Yu-Kai Chao
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Yu Yuan
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Sandra Burgstaller
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Anna Scotto Rosato
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Einar Krogsaeter
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Nicole Urban
- Rudolf-Boehm-Institute for Pharmacology and Toxicology, Universität Leipzig, Leipzig, Germany
| | - Katharina Jacob
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Ong Nam Phuong Nguyen
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Meghan T Miller
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.,Pharma Research and Early Development (pRED), Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Marco Keller
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Angelika M Vollmar
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Johann Schredelseker
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.,Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Michael Schaefer
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany.,Rudolf-Boehm-Institute for Pharmacology and Toxicology, Universität Leipzig, Leipzig, Germany
| | - Martin Biel
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Roland Malli
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | | | - Franz Bracher
- Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Sandip Patel
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
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19
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Krogsaeter EK, Biel M, Wahl-Schott C, Grimm C. The protein interaction networks of mucolipins and two-pore channels. Biochim Biophys Acta Mol Cell Res 2019; 1866:1111-1123. [PMID: 30395881 PMCID: PMC7111325 DOI: 10.1016/j.bbamcr.2018.10.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/24/2018] [Accepted: 10/26/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND The endolysosomal, non-selective cation channels, two-pore channels (TPCs) and mucolipins (TRPMLs), regulate intracellular membrane dynamics and autophagy. While partially compensatory for each other, isoform-specific intracellular distribution, cell-type expression patterns, and regulatory mechanisms suggest different channel isoforms confer distinct properties to the cell. SCOPE OF REVIEW Briefly, established TPC/TRPML functions and interaction partners ('interactomes') are discussed. Novel TRPML3 interactors are shown, and a meta-analysis of experimentally obtained channel interactomes conducted. Accordingly, interactomes are compared and contrasted, and subsequently described in detail for TPC1, TPC2, TRPML1, and TRPML3. MAJOR CONCLUSIONS TPC interactomes are well-defined, encompassing intracellular membrane organisation proteins. TRPML interactomes are varied, encompassing cardiac contractility- and chaperone-mediated autophagy proteins, alongside regulators of intercellular signalling. GENERAL SIGNIFICANCE Comprising recently proposed targets to treat cancers, infections, metabolic disease and neurodegeneration, the advancement of TPC/TRPML understanding is of considerable importance. This review proposes novel directions elucidating TPC/TRPML relevance in health and disease. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- Einar K Krogsaeter
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Munich (LMU) Nussbaumstrasse 26, 80336 Munich
| | - Martin Biel
- Department of Pharmacy - Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Germany
| | - Christian Wahl-Schott
- Hannover Medical School, Institute for Neurophysiology, OE 4230, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Christian Grimm
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Munich (LMU) Nussbaumstrasse 26, 80336 Munich.
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20
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Hammelmann V, Stieglitz MS, Hülle H, Le Meur K, Kass J, Brümmer M, Gruner C, Rötzer RD, Fenske S, Hartmann J, Zott B, Lüthi A, Spahn S, Moser M, Isbrandt D, Ludwig A, Konnerth A, Wahl-Schott C, Biel M. Abolishing cAMP sensitivity in HCN2 pacemaker channels induces generalized seizures. JCI Insight 2019; 4:126418. [PMID: 31045576 DOI: 10.1172/jci.insight.126418] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 04/02/2019] [Indexed: 12/17/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are dually gated channels that are operated by voltage and by neurotransmitters via the cAMP system. cAMP-dependent HCN regulation has been proposed to play a key role in regulating circuit behavior in the thalamus. By analyzing a knockin mouse model (HCN2EA), in which binding of cAMP to HCN2 was abolished by 2 amino acid exchanges (R591E, T592A), we found that cAMP gating of HCN2 is essential for regulating the transition between the burst and tonic modes of firing in thalamic dorsal-lateral geniculate (dLGN) and ventrobasal (VB) nuclei. HCN2EA mice display impaired visual learning, generalized seizures of thalamic origin, and altered NREM sleep properties. VB-specific deletion of HCN2, but not of HCN4, also induced these generalized seizures of the absence type, corroborating a key role of HCN2 in this particular nucleus for controlling consciousness. Together, our data define distinct pathological phenotypes resulting from the loss of cAMP-mediated gating of a neuronal HCN channel.
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Affiliation(s)
- Verena Hammelmann
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marc Sebastian Stieglitz
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Henrik Hülle
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Karim Le Meur
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jennifer Kass
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Manuela Brümmer
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christian Gruner
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - René Dominik Rötzer
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stefanie Fenske
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jana Hartmann
- Institute of Neuroscience, Technical University of Munich, Munich, Germany; and Munich Cluster for Systems Neurology (SyNergy) and Center for Integrated Protein Sciences (CIPSM), Munich, Germany
| | - Benedikt Zott
- Institute of Neuroscience, Technical University of Munich, Munich, Germany; and Munich Cluster for Systems Neurology (SyNergy) and Center for Integrated Protein Sciences (CIPSM), Munich, Germany
| | - Anita Lüthi
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Saskia Spahn
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Markus Moser
- Department for Molecular Medicine, Max-Planck-Institut für Biochemie, Martinsried, Germany
| | - Dirk Isbrandt
- DZNE Research Group, Experimental Neurophysiology, Institute for Molecular and Behavioral Neuroscience, University of Cologne, Germany
| | - Andreas Ludwig
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Arthur Konnerth
- Institute of Neuroscience, Technical University of Munich, Munich, Germany; and Munich Cluster for Systems Neurology (SyNergy) and Center for Integrated Protein Sciences (CIPSM), Munich, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany.,Institut für Neurophysiologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität München, Munich, Germany
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21
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Plesch E, Chen CC, Butz E, Scotto Rosato A, Krogsaeter EK, Yinan H, Bartel K, Keller M, Robaa D, Teupser D, Holdt LM, Vollmar AM, Sippl W, Puertollano R, Medina D, Biel M, Wahl-Schott C, Bracher F, Grimm C. Selective agonist of TRPML2 reveals direct role in chemokine release from innate immune cells. eLife 2018; 7:39720. [PMID: 30479274 PMCID: PMC6257821 DOI: 10.7554/elife.39720] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [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: 07/01/2018] [Accepted: 10/26/2018] [Indexed: 12/21/2022] Open
Abstract
Cytokines and chemokines are produced and secreted by a broad range of immune cells including macrophages. Remarkably, little is known about how these inflammatory mediators are released from the various immune cells. Here, the endolysosomal cation channel TRPML2 is shown to play a direct role in chemokine trafficking and secretion from murine macrophages. To demonstrate acute and direct involvement of TRPML2 in these processes, the first isoform-selective TRPML2 channel agonist was generated, ML2-SA1. ML2-SA1 was not only found to directly stimulate release of the chemokine CCL2 from macrophages but also to stimulate macrophage migration, thus mimicking CCL2 function. Endogenous TRPML2 is expressed in early/recycling endosomes as demonstrated by endolysosomal patch-clamp experimentation and ML2-SA1 promotes trafficking through early/recycling endosomes, suggesting CCL2 being transported and secreted via this pathway. These data provide a direct link between TRPML2 activation, CCL2 release and stimulation of macrophage migration in the innate immune response.
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Affiliation(s)
- Eva Plesch
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Cheng-Chang Chen
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Elisabeth Butz
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | | | - Einar K Krogsaeter
- Department of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilian University of Munich, Munich, Germany
| | - Hua Yinan
- Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Karin Bartel
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Marco Keller
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Dina Robaa
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Halle, Germany
| | - Daniel Teupser
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Lesca M Holdt
- Institute of Laboratory Medicine, University Hospital Munich, Munich, Germany
| | - Angelika M Vollmar
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Wolfgang Sippl
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Halle, Germany
| | - Rosa Puertollano
- Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Diego Medina
- Telethon Institute of Genetics and Medicine, Naples, Italy
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | | | - Franz Bracher
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich, Ludwig Maximilian University of Munich, Munich, Germany
| | - Christian Grimm
- Department of Pharmacology and Toxicology, Medical Faculty, Ludwig Maximilian University of Munich, Munich, Germany
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22
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Stieglitz MS, Fenske S, Hammelmann V, Becirovic E, Schöttle V, Delorme JE, Schöll-Weidinger M, Mader R, Deussing J, Wolfer DP, Seeliger MW, Albrecht U, Wotjak CT, Biel M, Michalakis S, Wahl-Schott C. Disturbed Processing of Contextual Information in HCN3 Channel Deficient Mice. Front Mol Neurosci 2018; 10:436. [PMID: 29375299 PMCID: PMC5767300 DOI: 10.3389/fnmol.2017.00436] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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: 07/13/2017] [Accepted: 12/18/2017] [Indexed: 12/31/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated channels (HCNs) in the nervous system are implicated in a variety of neuronal functions including learning and memory, regulation of vigilance states and pain. Dysfunctions or genetic loss of these channels have been shown to cause human diseases such as epilepsy, depression, schizophrenia, and Parkinson's disease. The physiological functions of HCN1 and HCN2 channels in the nervous system have been analyzed using genetic knockout mouse models. By contrast, there are no such genetic studies for HCN3 channels so far. Here, we use a HCN3-deficient (HCN3−/−) mouse line, which has been previously generated in our group to examine the expression and function of this channel in the CNS. Specifically, we investigate the role of HCN3 channels for the regulation of circadian rhythm and for the determination of behavior. Contrary to previous suggestions we find that HCN3−/− mice show normal visual, photic, and non-photic circadian function. In addition, HCN3−/− mice are impaired in processing contextual information, which is characterized by attenuated long-term extinction of contextual fear and increased fear to a neutral context upon repeated exposure.
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Affiliation(s)
- Marc S Stieglitz
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Stefanie Fenske
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Verena Hammelmann
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Elvir Becirovic
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Verena Schöttle
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - James E Delorme
- Neurobiochemistry of Circadian Rhythms, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Martha Schöll-Weidinger
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Robert Mader
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Jan Deussing
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - David P Wolfer
- Institute of Anatomy, University of Zurich, Zurich, Switzerland.,Department of Health Sciences and Technology, Institute of Human Movement Sciences and Sport, ETH Zurich, Zurich, Switzerland.,Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Mathias W Seeliger
- Ocular Neurodegeneration Research Group, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Urs Albrecht
- Neurobiochemistry of Circadian Rhythms, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Carsten T Wotjak
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Stylianos Michalakis
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians University, Munich, Germany
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23
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Barthmes M, Liao J, Jiang Y, Brüggemann A, Wahl-Schott C. Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology. J Gen Physiol 2017; 147:485-96. [PMID: 27241699 PMCID: PMC4886279 DOI: 10.1085/jgp.201611587] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/11/2016] [Indexed: 01/24/2023] Open
Abstract
NCX_Mj is a sodium–calcium exchanger from the archaebacterium Methanococcus jannaschii, whose crystal structure has been solved. Barthmes et al. use solid supported membrane–based electrophysiology to characterize NCX_Mj and reveal its functional similarity to eukaryotic isoforms. Sodium–calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium–calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)–based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.
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Affiliation(s)
- Maria Barthmes
- Nanion Technologies, 80636 Munich, Germany Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacology, Ludwig Maximilians University and DZHK (German Center for Cardiovascular Research), partner site Munich Heart Alliance, 81377 Munich, Germany
| | - Jun Liao
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390 School of Life Science and Technology, Shanghai Tech University, Shanghai 201210, China
| | - Youxing Jiang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390 Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | | | - Christian Wahl-Schott
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacology, Ludwig Maximilians University and DZHK (German Center for Cardiovascular Research), partner site Munich Heart Alliance, 81377 Munich, Germany
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24
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Chen CC, Butz ES, Chao YK, Grishchuk Y, Becker L, Heller S, Slaugenhaupt SA, Biel M, Wahl-Schott C, Grimm C. Small Molecules for Early Endosome-Specific Patch Clamping. Cell Chem Biol 2017; 24:907-916.e4. [PMID: 28732201 DOI: 10.1016/j.chembiol.2017.05.025] [Citation(s) in RCA: 33] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/30/2017] [Accepted: 05/26/2017] [Indexed: 12/31/2022]
Abstract
To resolve the subcellular distribution of endolysosomal ion channels, we have established a novel experimental approach to selectively patch clamp Rab5 positive early endosomes (EE) versus Rab7/LAMP1-positive late endosomes/lysosomes (LE/LY). To functionally characterize ion channels in endolysosomal membranes with the patch-clamp technique, it is important to develop techniques to selectively enlarge the respective organelles. We found here that two small molecules, wortmannin and latrunculin B, enlarge Rab5-positive EE when combined but not Rab7-, LAMP1-, or Rab11 (RE)-positive vesicles. The two compounds act rapidly, specifically, and are readily applicable in contrast to genetic approaches or previously used compounds such as vacuolin, which enlarges EE, RE, and LE/LY. We apply this approach here to measure currents mediated by TRPML channels, in particular TRPML3, which we found to be functionally active in both EE and LE/LY in overexpressing cells as well as in endogenously expressing CD11b+ lung-tissue macrophages.
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Affiliation(s)
- Cheng-Chang Chen
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Elisabeth S Butz
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Yu-Kai Chao
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Yulia Grishchuk
- Department of Neurology, Center for Human Genetic Research, Massachusetts General Hospital, Harvard University, Boston, MA 02114, USA
| | - Lars Becker
- Departments of Otolaryngology - HNS and Molecular & Cellular Physiology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Stefan Heller
- Departments of Otolaryngology - HNS and Molecular & Cellular Physiology, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Susan A Slaugenhaupt
- Department of Neurology, Center for Human Genetic Research, Massachusetts General Hospital, Harvard University, Boston, MA 02114, USA
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
| | - Christian Grimm
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
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25
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Castonguay J, Orth JHC, Müller T, Sleman F, Grimm C, Wahl-Schott C, Biel M, Mallmann RT, Bildl W, Schulte U, Klugbauer N. The two-pore channel TPC1 is required for efficient protein processing through early and recycling endosomes. Sci Rep 2017; 7:10038. [PMID: 28855648 PMCID: PMC5577145 DOI: 10.1038/s41598-017-10607-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [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: 05/19/2017] [Accepted: 08/11/2017] [Indexed: 02/06/2023] Open
Abstract
Two-pore channels (TPCs) are localized in endo-lysosomal compartments and assumed to play an important role for vesicular fusion and endosomal trafficking. Recently, it has been shown that both TPC1 and 2 were required for host cell entry and pathogenicity of Ebola viruses. Here, we investigate the cellular function of TPC1 using protein toxins as model substrates for distinct endosomal processing routes. Toxin uptake and activation through early endosomes but not processing through other compartments were reduced in TPC1 knockout cells. Detailed co-localization studies with subcellular markers confirmed predominant localization of TPC1 to early and recycling endosomes. Proteomic analysis of native TPC1 channels finally identified direct interaction with a distinct set of syntaxins involved in fusion of intracellular vesicles. Together, our results demonstrate a general role of TPC1 for uptake and processing of proteins in early and recycling endosomes, likely by providing high local Ca2+ concentrations required for SNARE-mediated vesicle fusion.
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Affiliation(s)
- Jan Castonguay
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany
| | - Joachim H C Orth
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany
| | - Thomas Müller
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany
| | - Faten Sleman
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany
| | - Christian Grimm
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University, Munich, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University, Munich, Germany
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University, Munich, Germany
| | - Robert Theodor Mallmann
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany
| | - Wolfgang Bildl
- Institute of Physiology II, Faculty of Medicine, Albert-Ludwigs-University, Hermann-Herder-Strasse 7, 79104, Freiburg, Germany
| | - Uwe Schulte
- Institute of Physiology II, Faculty of Medicine, Albert-Ludwigs-University, Hermann-Herder-Strasse 7, 79104, Freiburg, Germany.,Logopharm GmbH, Schlossstrasse 14, 79232, March-Buchheim, Germany.,Center for Biological Signaling Studies (BIOSS), Schänzlestrasse 18, 79104, Freiburg, Germany
| | - Norbert Klugbauer
- Institute of Experimental and Clinical Pharmacology and Toxicology, Faculty of Medicine, Albert-Ludwigs-University, Albertstrasse 25, 79104, Freiburg, Germany.
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26
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Grimm C, Butz E, Chen CC, Wahl-Schott C, Biel M. From mucolipidosis type IV to Ebola: TRPML and two-pore channels at the crossroads of endo-lysosomal trafficking and disease. Cell Calcium 2017; 67:148-155. [PMID: 28457591 DOI: 10.1016/j.ceca.2017.04.003] [Citation(s) in RCA: 53] [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: 02/27/2017] [Revised: 04/05/2017] [Accepted: 04/05/2017] [Indexed: 01/05/2023]
Abstract
What do lysosomal storage disorders such as mucolipidosis type IV have in common with Ebola, cancer cell migration, or LDL-cholesterol trafficking? LDL-cholesterol, certain bacterial toxins and viruses, growth factors, receptors, integrins, macromolecules destined for degradation or secretion are all sorted and transported via the endolysosomal system (ES). There are several pathways known in the ES, e.g. the degradation, the recycling, or the retrograde trafficking pathway. The ES comprises early and late endosomes, lysosomes and recycling endosomes as well as autophagosomes and lysosome related organelles. Contact sites between the ES and the endoplasmic reticulum or the Golgi apparatus may also be considered part of it. Dysfunction of this complex intracellular machinery can cause or contribute to the development of a number of diseases ranging from neurodegenerative, infectious, or metabolic diseases to retinal and pigmentation disorders as well as cancer and autophagy-related diseases. Endolysosomal ion channels such as mucolipins (TRPMLs) and two-pore channels (TPCs) play an important role in intracellular cation/calcium signaling and homeostasis and appear to critically contribute to the proper function of the endolysosomal trafficking network.
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Affiliation(s)
- Christian Grimm
- Munich Center for Integrated Protein Science CIPSM, Center for Drug Research, Ludwig-Maximilians-Universität, München, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany.
| | - Elisabeth Butz
- Munich Center for Integrated Protein Science CIPSM, Center for Drug Research, Ludwig-Maximilians-Universität, München, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany
| | - Cheng-Chang Chen
- Munich Center for Integrated Protein Science CIPSM, Center for Drug Research, Ludwig-Maximilians-Universität, München, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany
| | - Christian Wahl-Schott
- Munich Center for Integrated Protein Science CIPSM, Center for Drug Research, Ludwig-Maximilians-Universität, München, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany
| | - Martin Biel
- Munich Center for Integrated Protein Science CIPSM, Center for Drug Research, Ludwig-Maximilians-Universität, München, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Germany.
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27
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Grimm C, Chen CC, Wahl-Schott C, Biel M. Two-Pore Channels: Catalyzers of Endolysosomal Transport and Function. Front Pharmacol 2017; 8:45. [PMID: 28223936 PMCID: PMC5293812 DOI: 10.3389/fphar.2017.00045] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [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: 11/28/2016] [Accepted: 01/20/2017] [Indexed: 01/17/2023] Open
Abstract
Two-pore channels (TPCs) have recently emerged as a novel class of non-selective cation channels in the endolysosomal system. There are two members in the human genome, TPC1 and TPC2. Studies with TPC knockout and knockdown models have revealed that these channels participate in the regulation of multiple endolysosomal trafficking pathways which when dysregulated can lead to or influence the development of a range of different diseases such as lysosomal storage, metabolic, or infectious diseases. TPCs have been demonstrated to be activated by different endogenous stimuli, PI(3,5)P2 and NAADP, and ATP has been found to block TPC activation via mTOR. Loss of TPCs can lead to obesity and hypercholesterolemia, and to a slow-down of intracellular virus and bacterial toxin trafficking, it can affect VEGF-induced neoangiogenesis, autophagy, human hair pigmentation or the acrosome reaction in sperm. Moreover, physiological roles of TPCs in cardiac myocytes and pancreatic β cells have been postulated.
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Affiliation(s)
- Christian Grimm
- Center for Integrated Protein Science Munich, Ludwig Maximilian University of MunichMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig Maximilian University of MunichMunich, Germany
| | - Cheng-Chang Chen
- Center for Integrated Protein Science Munich, Ludwig Maximilian University of MunichMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig Maximilian University of MunichMunich, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science Munich, Ludwig Maximilian University of MunichMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig Maximilian University of MunichMunich, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich, Ludwig Maximilian University of MunichMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig Maximilian University of MunichMunich, Germany
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28
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Nguyen ONP, Grimm C, Schneider LS, Chao YK, Atzberger C, Bartel K, Watermann A, Ulrich M, Mayr D, Wahl-Schott C, Biel M, Vollmar AM. Two-Pore Channel Function Is Crucial for the Migration of Invasive Cancer Cells. Cancer Res 2017; 77:1427-1438. [PMID: 28108508 DOI: 10.1158/0008-5472.can-16-0852] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 11/16/2022]
Abstract
Metastatic invasion is the major cause of cancer-related deaths. In this study, we introduce two-pore channels (TPC), a recently described class of NAADP- and PI(3,5)P2-sensitive Ca2+-permeable cation channels in the endolysosomal system of cells, as candidate targets for the treatment of invasive cancers. Inhibition of the channel abrogated migration of metastatic cancer cells in vitro Silencing or pharmacologic inhibition of the two-pore channel TPC2 reduced lung metastasis of mammary mouse cancer cells. Disrupting TPC function halted trafficking of β1-integrin, leading to its accumulation in EEA1-positive early endosomes. As a consequence, invasive cancer cells were no longer able to form leading edges, which are required for adequate migration. Our findings link TPC to cancer cell migration and provide a preclinical proof of concept for their candidacy as targets to treat metastatic cancers. Cancer Res; 77(6); 1427-38. ©2017 AACR.
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Affiliation(s)
- Ong Nam Phuong Nguyen
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Christian Grimm
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University Munich, Munich, Germany
| | - Lina S Schneider
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Yu-Kai Chao
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University Munich, Munich, Germany
| | - Carina Atzberger
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Karin Bartel
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Anna Watermann
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Melanie Ulrich
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Doris Mayr
- Pathological Institute, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University Munich, Munich, Germany
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-University Munich, Munich, Germany.
| | - Angelika M Vollmar
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University Munich, Munich, Germany.
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29
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Butz ES, Ben-Johny M, Shen M, Yang PS, Sang L, Biel M, Yue DT, Wahl-Schott C. Quantifying macromolecular interactions in living cells using FRET two-hybrid assays. Nat Protoc 2016; 11:2470-2498. [DOI: 10.1038/nprot.2016.128] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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30
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Becirovic E, Böhm S, Nguyen ONP, Riedmayr LM, Hammelmann V, Schön C, Butz ES, Wahl-Schott C, Biel M, Michalakis S. AAV Vectors for FRET-Based Analysis of Protein-Protein Interactions in Photoreceptor Outer Segments. Front Neurosci 2016; 10:356. [PMID: 27516733 PMCID: PMC4963399 DOI: 10.3389/fnins.2016.00356] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [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: 04/20/2016] [Accepted: 07/14/2016] [Indexed: 11/18/2022] Open
Abstract
Fluorescence resonance energy transfer (FRET) is a powerful method for the detection and quantification of stationary and dynamic protein-protein interactions. Technical limitations have hampered systematic in vivo FRET experiments to study protein-protein interactions in their native environment. Here, we describe a rapid and robust protocol that combines adeno-associated virus (AAV) vector-mediated in vivo delivery of genetically encoded FRET partners with ex vivo FRET measurements. The method was established on acutely isolated outer segments of murine rod and cone photoreceptors and relies on the high co-transduction efficiency of retinal photoreceptors by co-delivered AAV vectors. The procedure can be used for the systematic analysis of protein-protein interactions of wild type or mutant outer segment proteins in their native environment. Conclusively, our protocol can help to characterize the physiological and pathophysiological relevance of photoreceptor specific proteins and, in principle, should also be transferable to other cell types.
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Affiliation(s)
- Elvir Becirovic
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Sybille Böhm
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Ong N P Nguyen
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Lisa M Riedmayr
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Verena Hammelmann
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Christian Schön
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Elisabeth S Butz
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Martin Biel
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Stylianos Michalakis
- Department of Pharmacy - Center for Integrated Protein Science Munich (CiPSM), Ludwig-Maximilians-Universität MünchenMunich, Germany; Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität MünchenMunich, Germany
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31
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Nguyen ONP, Böhm S, Gießl A, Butz ES, Wolfrum U, Brandstätter JH, Wahl-Schott C, Biel M, Becirovic E. Peripherin-2 differentially interacts with cone opsins in outer segments of cone photoreceptors. Hum Mol Genet 2016; 25:2367-2377. [PMID: 27033727 DOI: 10.1093/hmg/ddw103] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/16/2016] [Accepted: 03/17/2016] [Indexed: 11/13/2022] Open
Abstract
Peripherin-2 is a glycomembrane protein exclusively expressed in the light-sensing compartments of rod and cone photoreceptors designated as outer segments (OS). Mutations in peripherin-2 are associated with degenerative retinal diseases either affecting rod or cone photoreceptors. While peripherin-2 has been extensively studied in rods, there is only little information on its supramolecular organization and function in cones. Recently, we have demonstrated that peripherin-2 interacts with the light detector rhodopsin in OS of rods. It remains unclear, however, if peripherin-2 also binds to cone opsins. Here, using a combination of co-immunoprecipitation analyses, transmission electron microscopy (TEM)-based immunolabeling experiments, and quantitative fluorescence resonance energy transfer (FRET) measurements in cone OS of wild type mice, we demonstrate that peripherin-2 binds to both, S-opsin and M-opsin. However, FRET-based quantification of the respective interactions indicated significantly less stringent binding of peripherin-2 to S-opsin compared to its interaction with M-opsin. Subsequent TEM-studies also showed less co-localization of peripherin-2 and S-opsin in cone OS compared to peripherin-2 and M-opsin. Furthermore, quantitative FRET analysis in acutely isolated cone OS revealed that the cone degeneration-causing V268I mutation in peripherin-2 selectively reduced binding to M-opsin without affecting the peripherin-2 interaction to S-opsin or rhodopsin. The differential binding of peripherin-2 to cone opsins and the mutant-specific interference with the peripherin-2/M-opsin binding points to a novel role of peripherin-2 in cones and might contribute to understanding the differential penetrance of certain peripherin-2 mutations in rods and cones. Finally, our results provide a proof-of-principle for quantitative FRET measurements of protein-protein interactions in cone OS.
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Affiliation(s)
- O N Phuong Nguyen
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Sybille Böhm
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Andreas Gießl
- Department of Biology, Animal Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91058 Erlangen, Germany and
| | - Elisabeth S Butz
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Uwe Wolfrum
- Cell and Matrix Biology, Institute of Zoology, Johannes-Gutenberg Universität Mainz, 55128 Mainz, Germany
| | - Johann H Brandstätter
- Department of Biology, Animal Physiology, Friedrich-Alexander Universität Erlangen-Nürnberg, 91058 Erlangen, Germany and
| | - Christian Wahl-Schott
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Martin Biel
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
| | - Elvir Becirovic
- Munich Center for Integrated Protein Science CIPS , 81377 München, Germany, .,Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 München, Germany
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Alberdi A, Gomis-Perez C, Bernardo-Seisdedos G, Alaimo A, Malo C, Aldaregia J, Lopez-Robles C, Areso P, Butz E, Wahl-Schott C, Villarroel A. Uncoupling PIP2-calmodulin regulation of Kv7.2 channels by an assembly destabilizing epileptogenic mutation. J Cell Sci 2015; 128:4014-23. [PMID: 26359296 DOI: 10.1242/jcs.176420] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 09/09/2015] [Indexed: 01/15/2023] Open
Abstract
We show that the combination of an intracellular bi-partite calmodulin (CaM)-binding site and a distant assembly region affect how an ion channel is regulated by a membrane lipid. Our data reveal that regulation by phosphatidylinositol(4,5)bisphosphate (PIP2) and stabilization of assembled Kv7.2 subunits by intracellular coiled-coil regions far from the membrane are coupled molecular processes. Live-cell fluorescence energy transfer measurements and direct binding studies indicate that remote coiled-coil formation creates conditions for different CaM interaction modes, each conferring different PIP2 dependency to Kv7.2 channels. Disruption of coiled-coil formation by epilepsy-causing mutation decreases apparent CaM-binding affinity and interrupts CaM influence on PIP2 sensitivity.
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Affiliation(s)
- Araitz Alberdi
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Carolina Gomis-Perez
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Ganeko Bernardo-Seisdedos
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Alessandro Alaimo
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Covadonga Malo
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Juncal Aldaregia
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Carlos Lopez-Robles
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Pilar Areso
- Departament de Farmacología, UPV/EHU, Universidad del País Vasco, Barrio Sarriena s/n, Leioa 48940, Spain
| | - Elisabeth Butz
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy, Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, München 81377, Germany
| | - Alvaro Villarroel
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas, CSIC, UPV/EHU, Barrio Sarriena s/n, Leioa 48940, Spain
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Ruas M, Davis LC, Chen CC, Morgan AJ, Chuang KT, Walseth TF, Grimm C, Garnham C, Powell T, Platt N, Platt FM, Biel M, Wahl-Schott C, Parrington J, Galione A. Expression of Ca²⁺-permeable two-pore channels rescues NAADP signalling in TPC-deficient cells. EMBO J 2015; 34:1743-58. [PMID: 25872774 PMCID: PMC4516428 DOI: 10.15252/embj.201490009] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 03/11/2015] [Indexed: 01/26/2023] Open
Abstract
The second messenger NAADP triggers Ca2+ release from endo-lysosomes. Although two-pore channels (TPCs) have been proposed to be regulated by NAADP, recent studies have challenged this. By generating the first mouse line with demonstrable absence of both Tpcn1 and Tpcn2 expression (Tpcn1/2−/−), we show that the loss of endogenous TPCs abolished NAADP-dependent Ca2+ responses as assessed by single-cell Ca2+ imaging or patch-clamp of single endo-lysosomes. In contrast, currents stimulated by PI(3,5)P2 were only partially dependent on TPCs. In Tpcn1/2−/− cells, NAADP sensitivity was restored by re-expressing wild-type TPCs, but not by mutant versions with impaired Ca2+-permeability, nor by TRPML1. Another mouse line formerly reported as TPC-null likely expresses truncated TPCs, but we now show that these truncated proteins still support NAADP-induced Ca2+ release. High-affinity [32P]NAADP binding still occurs in Tpcn1/2−/− tissue, suggesting that NAADP regulation is conferred by an accessory protein. Altogether, our data establish TPCs as Ca2+-permeable channels indispensable for NAADP signalling.
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Affiliation(s)
- Margarida Ruas
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Lianne C Davis
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Cheng-Chang Chen
- Center for Integrated Protein Science CIPS-M and Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | | | - Kai-Ting Chuang
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Timothy F Walseth
- Pharmacology Department, University of Minnesota, Minneapolis, MN, USA
| | - Christian Grimm
- Center for Integrated Protein Science CIPS-M and Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Clive Garnham
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Trevor Powell
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Nick Platt
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Frances M Platt
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Martin Biel
- Center for Integrated Protein Science CIPS-M and Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science CIPS-M and Department of Pharmacy - Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - John Parrington
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Oxford, UK
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34
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Sakurai Y, Kolokoltsov AA, Chen CC, Tidwell MW, Bauta WE, Klugbauer N, Grimm C, Wahl-Schott C, Biel M, Davey RA. Ebola virus. Two-pore channels control Ebola virus host cell entry and are drug targets for disease treatment. Science 2015; 347:995-8. [PMID: 25722412 DOI: 10.1126/science.1258758] [Citation(s) in RCA: 394] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Ebola virus causes sporadic outbreaks of lethal hemorrhagic fever in humans, but there is no currently approved therapy. Cells take up Ebola virus by macropinocytosis, followed by trafficking through endosomal vesicles. However, few factors controlling endosomal virus movement are known. Here we find that Ebola virus entry into host cells requires the endosomal calcium channels called two-pore channels (TPCs). Disrupting TPC function by gene knockout, small interfering RNAs, or small-molecule inhibitors halted virus trafficking and prevented infection. Tetrandrine, the most potent small molecule that we tested, inhibited infection of human macrophages, the primary target of Ebola virus in vivo, and also showed therapeutic efficacy in mice. Therefore, TPC proteins play a key role in Ebola virus infection and may be effective targets for antiviral therapy.
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Affiliation(s)
| | | | - Cheng-Chang Chen
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | | | - Norbert Klugbauer
- Institute for Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Christian Grimm
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Robert A Davey
- Texas Biomedical Research Institute, San Antonio, TX, USA.
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35
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Grimm C, Chen CC, Butz E, Biel M, Wahl-Schott C. High Susceptibility to Non-Alcoholic Fatty Liver Disease in Two-Pore Channel 2-Deficient Mice. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.3176] [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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36
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Grimm C, Holdt LM, Chen CC, Hassan S, Müller C, Jörs S, Cuny H, Kissing S, Schröder B, Butz E, Northoff B, Castonguay J, Luber CA, Moser M, Spahn S, Lüllmann-Rauch R, Fendel C, Klugbauer N, Griesbeck O, Haas A, Mann M, Bracher F, Teupser D, Saftig P, Biel M, Wahl-Schott C. High susceptibility to fatty liver disease in two-pore channel 2-deficient mice. Nat Commun 2014; 5:4699. [DOI: 10.1038/ncomms5699] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 07/10/2014] [Indexed: 12/15/2022] Open
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37
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Chen CC, Keller M, Hess M, Schiffmann R, Urban N, Wolfgardt A, Schaefer M, Bracher F, Biel M, Wahl-Schott C, Grimm C. A small molecule restores function to TRPML1 mutant isoforms responsible for mucolipidosis type IV. Nat Commun 2014; 5:4681. [PMID: 25119295 DOI: 10.1038/ncomms5681] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [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: 05/23/2014] [Accepted: 07/11/2014] [Indexed: 11/08/2022] Open
Abstract
Mucolipidosis type IV (MLIV) is an autosomal recessive lysosomal storage disorder often characterized by severe neurodevelopmental abnormalities and neuro-retinal degeneration. Mutations in the TRPML1 gene are causative for MLIV. We used lead optimization strategies to identify--and MLIV patient fibroblasts to test--small-molecule activators for their potential to restore TRPML1 mutant channel function. Using the whole-lysosome planar patch-clamp technique, we found that activation of MLIV mutant isoforms by the endogenous ligand PI(3,5)P2 is strongly reduced, while activity can be increased using synthetic ligands. We also found that the F465L mutation renders TRPML1 pH insensitive, while F408Δ impacts synthetic ligand binding. Trafficking defects and accumulation of zinc in lysosomes of MLIV mutant fibroblasts can be rescued by the small molecule treatment. Collectively, our data demonstrate that small molecules can be used to restore channel function and rescue disease associated abnormalities in patient cells expressing specific MLIV point mutations.
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Affiliation(s)
- Cheng-Chang Chen
- 1] Department of Pharmacy-Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Munchen 81377, Germany [2]
| | - Marco Keller
- 1] Department of Pharmacy, Ludwig-Maximilians-Universität München, Munchen 81377, Germany [2]
| | - Martin Hess
- Department of Biology, Ludwig-Maximilians-Universität München, Munchen 82152, Germany
| | - Raphael Schiffmann
- Institute of Metabolic Disease, Baylor Research Institute, Dallas, Texas, USA
| | - Nicole Urban
- Rudolf-Boehm-Institute for Pharmacology and Toxicolgy, Universität Leipzig, Leipzig 04107, Germany
| | - Annette Wolfgardt
- Department of Pharmacy, Ludwig-Maximilians-Universität München, Munchen 81377, Germany
| | - Michael Schaefer
- Rudolf-Boehm-Institute for Pharmacology and Toxicolgy, Universität Leipzig, Leipzig 04107, Germany
| | - Franz Bracher
- Department of Pharmacy, Ludwig-Maximilians-Universität München, Munchen 81377, Germany
| | - Martin Biel
- Department of Pharmacy-Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Munchen 81377, Germany
| | - Christian Wahl-Schott
- Department of Pharmacy-Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Munchen 81377, Germany
| | - Christian Grimm
- 1] Department of Pharmacy-Center for Drug Research and Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität München, Munchen 81377, Germany [2]
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38
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Soltysinska E, Bentzen BH, Barthmes M, Hattel H, Thrush AB, Harper ME, Qvortrup K, Larsen FJ, Schiffer TA, Losa-Reyna J, Straubinger J, Kniess A, Thomsen MB, Brüggemann A, Fenske S, Biel M, Ruth P, Wahl-Schott C, Boushel RC, Olesen SP, Lukowski R. KCNMA1 encoded cardiac BK channels afford protection against ischemia-reperfusion injury. PLoS One 2014; 9:e103402. [PMID: 25072914 PMCID: PMC4114839 DOI: 10.1371/journal.pone.0103402] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 07/01/2014] [Indexed: 12/18/2022] Open
Abstract
Mitochondrial potassium channels have been implicated in myocardial protection mediated through pre-/postconditioning. Compounds that open the Ca2+- and voltage-activated potassium channel of big-conductance (BK) have a pre-conditioning-like effect on survival of cardiomyocytes after ischemia/reperfusion injury. Recently, mitochondrial BK channels (mitoBKs) in cardiomyocytes were implicated as infarct-limiting factors that derive directly from the KCNMA1 gene encoding for canonical BKs usually present at the plasma membrane of cells. However, some studies challenged these cardio-protective roles of mitoBKs. Herein, we present electrophysiological evidence for paxilline- and NS11021-sensitive BK-mediated currents of 190 pS conductance in mitoplasts from wild-type but not BK-/- cardiomyocytes. Transmission electron microscopy of BK-/- ventricular muscles fibres showed normal ultra-structures and matrix dimension, but oxidative phosphorylation capacities at normoxia and upon re-oxygenation after anoxia were significantly attenuated in BK-/- permeabilized cardiomyocytes. In the absence of BK, post-anoxic reactive oxygen species (ROS) production from cardiomyocyte mitochondria was elevated indicating that mitoBK fine-tune the oxidative state at hypoxia and re-oxygenation. Because ROS and the capacity of the myocardium for oxidative metabolism are important determinants of cellular survival, we tested BK-/- hearts for their response in an ex-vivo model of ischemia/reperfusion (I/R) injury. Infarct areas, coronary flow and heart rates were not different between wild-type and BK-/- hearts upon I/R injury in the absence of ischemic pre-conditioning (IP), but differed upon IP. While the area of infarction comprised 28±3% of the area at risk in wild-type, it was increased to 58±5% in BK-/- hearts suggesting that BK mediates the beneficial effects of IP. These findings suggest that cardiac BK channels are important for proper oxidative energy supply of cardiomyocytes at normoxia and upon re-oxygenation after prolonged anoxia and that IP might indeed favor survival of the myocardium upon I/R injury in a BK-dependent mode stemming from both mitochondrial post-anoxic ROS modulation and non-mitochondrial localizations.
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MESH Headings
- Animals
- Cell Hypoxia
- Disease Models, Animal
- Energy Metabolism
- Indoles/pharmacology
- Ischemic Preconditioning
- Large-Conductance Calcium-Activated Potassium Channel alpha Subunits/genetics
- Large-Conductance Calcium-Activated Potassium Channel alpha Subunits/metabolism
- Large-Conductance Calcium-Activated Potassium Channels/chemistry
- Large-Conductance Calcium-Activated Potassium Channels/genetics
- Large-Conductance Calcium-Activated Potassium Channels/metabolism
- Membrane Potential, Mitochondrial/drug effects
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mitochondria, Heart/metabolism
- Muscle Fibers, Skeletal/ultrastructure
- Muscle, Skeletal/metabolism
- Myocardium/metabolism
- Myocytes, Cardiac/cytology
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Oxidative Phosphorylation/drug effects
- Reactive Oxygen Species/metabolism
- Reperfusion Injury/metabolism
- Reperfusion Injury/pathology
- Tetrazoles/pharmacology
- Thiourea/analogs & derivatives
- Thiourea/pharmacology
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Affiliation(s)
- Ewa Soltysinska
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bo Hjorth Bentzen
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Maria Barthmes
- Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
- Nanion Technologies GmbH, Munich, Germany
| | - Helle Hattel
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - A. Brianne Thrush
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Klaus Qvortrup
- Department of Biomedical Sciences, Core Facility for Integrated Microscopy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Filip J. Larsen
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Tomas A. Schiffer
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Jose Losa-Reyna
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Julia Straubinger
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Angelina Kniess
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Morten Bækgaard Thomsen
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Stefanie Fenske
- Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science Munich (CIPSM), Ludwig-Maximilians-Universität, Munich, Germany; Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität, Munich, Germany
| | - Robert Christopher Boushel
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren-Peter Olesen
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- * E-mail: (SPO); (RL)
| | - Robert Lukowski
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
- * E-mail: (SPO); (RL)
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39
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Becirovic E, Nguyen ONP, Paparizos C, Butz ES, Stern-Schneider G, Wolfrum U, Hauck SM, Ueffing M, Wahl-Schott C, Michalakis S, Biel M. Peripherin-2 couples rhodopsin to the CNG channel in outer segments of rod photoreceptors. Hum Mol Genet 2014; 23:5989-97. [PMID: 24963162 DOI: 10.1093/hmg/ddu323] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Outer segments (OSs) of rod photoreceptors are cellular compartments specialized in the conversion of light into electrical signals. This process relies on the light-triggered change in the intracellular levels of cyclic guanosine monophosphate, which in turn controls the activity of cyclic nucleotide-gated (CNG) channels in the rod OS plasma membrane. The rod CNG channel is a macromolecular complex that in its core harbors the ion-conducting CNGA1 and CNGB1a subunits. To identify additional proteins of the complex that interact with the CNGB1a core subunit, we applied affinity purification of mouse retinal proteins followed by mass spectrometry. In combination with in vitro and in vivo co-immunoprecipitation and fluorescence resonance energy transfer (FRET), we found that the tetraspanin peripherin-2 links CNGB1a to the light-detector rhodopsin. Using immunoelectron microscopy, we found that this peripherin-2/rhodopsin/CNG channel complex localizes to the contact region between the disk rims and the plasma membrane. FRET measurements revealed that the fourth transmembrane domain (TM4) of peripherin-2 is required for the interaction with rhodopsin. Quantitatively, the binding affinity of the peripherin-2/rhodopsin interaction was in a similar range as that observed for rhodopsin dimers. Finally, we demonstrate that the p.G266D retinitis pigmentosa mutation found within TM4 selectively abolishes the binding of peripherin-2 to rhodopsin. This finding suggests that the specific disruption of the rhodopsin/peripherin-2 interaction in the p.G266D mutant might contribute to the pathophysiology in affected persons.
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Affiliation(s)
- Elvir Becirovic
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - O N Phuong Nguyen
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Christos Paparizos
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Elisabeth S Butz
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Gabi Stern-Schneider
- Cell and Matrix Biology, Institute of Zoology, Johannes-Gutenberg Universität Mainz, Mainz, Germany
| | - Uwe Wolfrum
- Cell and Matrix Biology, Institute of Zoology, Johannes-Gutenberg Universität Mainz, Mainz, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, German Research Center for Environmental Health GmbH, München, Germany and
| | - Marius Ueffing
- Research Unit Protein Science, Helmholtz Center Munich, German Research Center for Environmental Health GmbH, München, Germany and Center for Ophthalmology, Institute for Ophthalmic Research, Tübingen, Germany
| | - Christian Wahl-Schott
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Stylianos Michalakis
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany
| | - Martin Biel
- Munich Center for Integrated Protein Science CIPSM and Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, München, Germany,
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40
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Wahl-Schott C, Fenske S, Biel M. HCN channels: new roles in sinoatrial node function. Curr Opin Pharmacol 2014; 15:83-90. [DOI: 10.1016/j.coph.2013.12.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 12/16/2013] [Accepted: 12/17/2013] [Indexed: 11/25/2022]
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41
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Barthmes M, Jose MDF, Birkner JP, Brüggemann A, Wahl-Schott C, Koçer A. Studying mechanosensitive ion channels with an automated patch clamp. Eur Biophys J 2014; 43:97-104. [DOI: 10.1007/s00249-014-0944-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 02/01/2014] [Indexed: 10/25/2022]
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42
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Arndt L, Castonguay J, Arlt E, Meyer D, Hassan S, Borth H, Zierler S, Wennemuth G, Breit A, Biel M, Wahl-Schott C, Gudermann T, Klugbauer N, Boekhoff I. NAADP and the two-pore channel protein 1 participate in the acrosome reaction in mammalian spermatozoa. Mol Biol Cell 2014; 25:948-64. [PMID: 24451262 PMCID: PMC3952862 DOI: 10.1091/mbc.e13-09-0523] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A TPCN1 gene–deficient mouse strain is used to show that two convergent working NAADP-dependent pathways with nonoverlapping activation and self-inactivation profiles for distinct NAADP concentrations drive acrosomal exocytosis, by which TPC1 is central for the pathway activated by low-micromolar NAADP concentrations. The functional relationship between the formation of hundreds of fusion pores during the acrosome reaction in spermatozoa and the mobilization of calcium from the acrosome has been determined only partially. Hence, the second messenger NAADP, promoting efflux of calcium from lysosome-like compartments and one of its potential molecular targets, the two-pore channel 1 (TPC1), were analyzed for its involvement in triggering the acrosome reaction using a TPCN1 gene–deficient mouse strain. The present study documents that TPC1 and NAADP-binding sites showed a colocalization at the acrosomal region and that treatment of spermatozoa with NAADP resulted in a loss of the acrosomal vesicle that showed typical properties described for TPCs: Registered responses were not detectable for its chemical analogue NADP and were blocked by the NAADP antagonist trans-Ned-19. In addition, two narrow bell-shaped dose-response curves were identified with maxima in either the nanomolar or low micromolar NAADP concentration range, where TPC1 was found to be responsible for activating the low affinity pathway. Our finding that two convergent NAADP-dependent pathways are operative in driving acrosomal exocytosis supports the concept that both NAADP-gated cascades match local NAADP concentrations with the efflux of acrosomal calcium, thereby ensuring complete fusion of the large acrosomal vesicle.
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Affiliation(s)
- Lilli Arndt
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians University, 81377 München, Germany Department of Pharmacy, Ludwig-Maximilians University, 81377 München, Germany Institute for Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-University, 79104 Freiburg, Germany Institute for Anatomy, University of Duisburg-Essen, 45141 Essen, Germany
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43
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Cao-Ehlker X, Zong X, Hammelmann V, Gruner C, Fenske S, Michalakis S, Wahl-Schott C, Biel M. Up-regulation of hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3) by specific interaction with K+ channel tetramerization domain-containing protein 3 (KCTD3). J Biol Chem 2013; 288:7580-7589. [PMID: 23382386 DOI: 10.1074/jbc.m112.434803] [Citation(s) in RCA: 15] [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: 01/09/2023] Open
Abstract
Most ion channels consist of the principal ion-permeating core subunit(s) and accessory proteins that are assembled with the channel core. The biological functions of the latter proteins are diverse and include the regulation of the biophysical properties of the ion channel, its connection to signaling pathways and the control of its cell surface expression. There is recent evidence that native hyperpolarization-activated cyclic nucleotide-gated channel complexes (HCN1-4) also contain accessory subunits, among which TRIP8b (tetratricopeptide repeat-containing Rab8b-interacting protein) has been most extensively studied. Here, we identify KCTD3, a so far uncharacterized member of the potassium channel tetramerization-domain containing (KCTD) protein family as an HCN3-interacting protein. KCTD3 is widely expressed in brain and some non-neuronal tissues and colocalizes with HCN3 in specific regions of the brain including hypothalamus. Within the HCN channel family, KCTD3 specifically binds to HCN3 and leads to a profound up-regulation of cell surface expression and current density of this channel. HCN3 can also functionally interact with TRIP8b; however, we found no evidence for channel complexes containing both TRIP8b and KCTD3. The C terminus of HCN3 is crucially required for functional interaction with KCTD3. Replacement of the cytosolic C terminus of HCN2 by the corresponding domain of HCN3 renders HCN2 sensitive to regulation by KCTD3. The C-terminal-half of KCTD3 is sufficient for binding to HCN3. However, the complete protein including the N-terminal tetramerization domain is needed for HCN3 current up-regulation. Together, our experiments indicate that KCTD3 is an accessory subunit of native HCN3 complexes.
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Affiliation(s)
- Xiaochun Cao-Ehlker
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Xiangang Zong
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Verena Hammelmann
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Christian Gruner
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Stefanie Fenske
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Stylianos Michalakis
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Christian Wahl-Schott
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 81377 Munich, Germany.
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Abstract
Hyperpolarization-activated cyclic nucleotide gated (HCN) channels pass a cationic current (I(h)/I(f)) that crucially contributes to the slow diastolic depolarization (SDD) of sinoatrial pacemaker cells and, hence, is a key determinant of cardiac automaticity and the generation of the heartbeat. However, there is growing evidence that HCN channels are not restricted to the spontaneously active cells of the sinoatrial node and the conduction system but are also present in ventricular cardiomyocytes that produce an action potential lacking SDD. This observation raises the question of the principal function(s) of HCN channels in working myocardium. Our recent analysis of an HCN3-deficient (HCN3-/-) mouse line has shed new light on this central question. We propose that HCN channels contribute to the ventricular action potential waveform, specifically during late repolarization. In this review, we outline this new concept.
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Affiliation(s)
- Stefanie Fenske
- Center for Integrated Protein Science CIPS-M and Zentrum für Pharmaforschung-Department Pharmazie, Ludwig-Maximilians-Universität München, Munich, Germany
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45
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Barthmes M, Donald F. Jose M, Fertig N, Wahl-Schott C, Kocer A, Bruggemann A. Electrophysiological Characterization of Mechanosensitive Ion Channels in Native Bacterial Membranes. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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46
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Zong X, Krause S, Chen CC, Krüger J, Gruner C, Cao-Ehlker X, Fenske S, Wahl-Schott C, Biel M. Regulation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channel activity by cCMP. J Biol Chem 2012; 287:26506-12. [PMID: 22715094 DOI: 10.1074/jbc.m112.357129] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Activation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels is facilitated in vivo by direct binding of the second messenger cAMP. This process plays a fundamental role in the fine-tuning of HCN channel activity and is critical for the modulation of cardiac and neuronal rhythmicity. Here, we identify the pyrimidine cyclic nucleotide cCMP as another regulator of HCN channels. We demonstrate that cCMP shifts the activation curves of two members of the HCN channel family, HCN2 and HCN4, to more depolarized voltages. Moreover, cCMP speeds up activation and slows down deactivation kinetics of these channels. The two other members of the HCN channel family, HCN1 and HCN3, are not sensitive to cCMP. The modulatory effect of cCMP is reversible and requires the presence of a functional cyclic nucleotide-binding domain. We determined an EC(50) value of ∼30 μm for cCMP compared with 1 μm for cAMP. Notably, cCMP is a partial agonist of HCN channels, displaying an efficacy of ∼0.6. cCMP increases the frequency of pacemaker potentials from isolated sinoatrial pacemaker cells in the presence of endogenous cAMP concentrations. Electrophysiological recordings indicated that this increase is caused by a depolarizing shift in the activation curve of the native HCN current, which in turn leads to an enhancement of the slope of the diastolic depolarization of sinoatrial node cells. In conclusion, our findings establish cCMP as a gating regulator of HCN channels and indicate that this cyclic nucleotide has to be considered in HCN channel-regulated processes.
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Affiliation(s)
- Xiangang Zong
- Center for Integrated Protein Science (CIPSM) and Zentrum für Pharmaforschung, Department Pharmazie, Ludwig-Maximilians-Universität München, 80539 Munich, Germany
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Abstract
The transient receptor potential (TRP) channels TRPML1, TRPML2, and TRPML3 (also called mucolipins 1-3 or MCOLN1-3) are nonselective cation channels. Mutations in the Trpml1 gene cause mucolipidosis type IV in humans with clinical features including psychomotor retardation, corneal clouding, and retinal degeneration, whereas mutations in the Trpml3 gene cause deafness, circling behavior, and coat color dilution in mice. No disease-causing mutations are reported for the Trpml2 gene. Like TRPML channels, which are expressed in the endolysosomal pathway, two-pore channels (TPCs), namely TPC1, TPC2, and TPC3, are found in intracellular organelles, in particular in endosomes and lysosomes. Both TRPML channels and TPCs may function as calcium/cation release channels in endosomes, lysosomes, and lysosome-related organelles with TRPMLs being activated by phosphatidylinositol 3,5-bisphosphate and regulated by pH and TPCs being activated by nicotinic acid adenine dinucleotide phosphate in a calcium- and pH-dependent manner. They may also be involved in endolysosomal transport and fusion processes, e.g., as intracellular calcium sources. Currently, however, the exact physiological roles of TRPML channels and TPCs remain quite elusive, and whether TRPML channels are purely endolysosomal ion channels or whether they may also be functionally active at the plasma membrane in vivo remains to be determined.
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Affiliation(s)
- Christian Grimm
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, 81377 Germany.
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48
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Fenske S, Michalakis S, Hofmann F, Wahl-Schott C, Biel M. HCN3 Contributes to the Ventricular Action Potential Waveform in the Murine Heart. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.717] [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: 11/27/2022] Open
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49
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Fenske S, Mader R, Scharr A, Paparizos C, Cao-Ehlker X, Michalakis S, Shaltiel L, Weidinger M, Stieber J, Feil S, Feil R, Hofmann F, Wahl-Schott C, Biel M. HCN3 contributes to the ventricular action potential waveform in the murine heart. Circ Res 2011; 109:1015-23. [PMID: 21903939 DOI: 10.1161/circresaha.111.246173] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [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: 11/16/2022]
Abstract
RATIONALE The hyperpolarization-activated current I(h) that is generated by hyperpolarization-activated cyclic nucleotide-gated channels (HCNs) plays a key role in the control of pacemaker activity in sinoatrial node cells of the heart. By contrast, it is unclear whether I(h) is also relevant for normal function of cardiac ventricles. OBJECTIVE To study the role of the HCN3-mediated component of ventricular I(h) in normal ventricular function. METHODS AND RESULTS To test the hypothesis that HCN3 regulates the ventricular action potential waveform, we have generated and analyzed a HCN3-deficient mouse line. At basal heart rate, mice deficient for HCN3 displayed a profound increase in the T-wave amplitude in telemetric electrocardiographic measurements. Action potential recordings on isolated ventricular myocytes indicate that this effect was caused by an acceleration of the late repolarization phase in epicardial myocytes. Furthermore, the resting membrane potential was shifted to more hyperpolarized potentials in HCN3-deficient mice. Cardiomyocytes of HCN3-deficient mice displayed approximately 30% reduction of total I(h). At physiological ionic conditions, the HCN3-mediated current had a reversal potential of approximately -35 mV and displayed ultraslow deactivation kinetics. CONCLUSIONS We propose that HCN3 together with other members of the HCN channel family confer a depolarizing background current that regulates ventricular resting potential and counteracts the action of hyperpolarizing potassium currents in late repolarization. In conclusion, our data indicate that HCN3 plays an important role in shaping the cardiac action potential waveform.
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Affiliation(s)
- Stefanie Fenske
- Center for Integrated Protein Science CIPS-M, Department Pharmazie, Ludwig-Maximilians-Universität München, München, Germany
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50
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Schieder M, Hassan S, Roetzer K, Biel M, Wahl-Schott C. Permeation Properties of Two Pore Channel 2 (TPCN2)-Mediated Ca2+ Currents Recorded from Single Lysosomes. Biophys J 2011. [DOI: 10.1016/j.bpj.2010.12.1581] [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: 10/18/2022] Open
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