1
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Shrivastava A, Kumar A, Aggarwal LM, Pradhan S, Choudhary S, Ashish A, Kashyap K, Mishra S. Evolution of Bioelectric Membrane Potentials: Implications in Cancer Pathogenesis and Therapeutic Strategies. J Membr Biol 2024:10.1007/s00232-024-00323-2. [PMID: 39183198 DOI: 10.1007/s00232-024-00323-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Accepted: 08/16/2024] [Indexed: 08/27/2024]
Abstract
Electrophysiology typically deals with the electrical properties of excitable cells like neurons and muscles. However, all other cells (non-excitable) also possess bioelectric membrane potentials for intracellular and extracellular communications. These membrane potentials are generated by different ions present in fluids available in and outside the cell, playing a vital role in communication and coordination between the cell and its organelles. Bioelectric membrane potential variations disturb cellular ionic homeostasis and are characteristic of many diseases, including cancers. A rapidly increasing interest has emerged in sorting out the electrophysiology of cancer cells. Compared to healthy cells, the distinct electrical properties exhibited by cancer cells offer a unique way of understanding cancer development, migration, and progression. Decoding the altered bioelectric signals influenced by fluctuating electric fields benefits understanding cancer more closely. While cancer research has predominantly focussed on genetic and molecular traits, the delicate area of electrophysiological characteristics has increasingly gained prominence. This review explores the historical exploration of electrophysiology in the context of cancer cells, shedding light on how alterations in bioelectric membrane potentials, mediated by ion channels and gap junctions, contribute to the pathophysiology of cancer.
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Affiliation(s)
- Anju Shrivastava
- Department of Physiology, Chhattisgarh Institute of Medical Sciences, Bilaspur, India.
| | - Amit Kumar
- Department of Anatomy, Chhattisgarh Institute of Medical Sciences, Bilaspur, India
| | - Lalit Mohan Aggarwal
- Radiotherapy and Radiation Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Satyajit Pradhan
- Radiation Oncology, Mahamana Pandit Madhan Mohan Malaviya Cancer Centre, Varanasi, India
| | - Sunil Choudhary
- Radiotherapy and Radiation Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Ashish Ashish
- Department of Anatomy, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
| | - Keshav Kashyap
- Department of Physiology, Chhattisgarh Institute of Medical Sciences, Bilaspur, India
| | - Shivani Mishra
- Department of Anatomy, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
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2
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Abbas F, Blömer LA, Millet H, Montnach J, De Waard M, Canepari M. Analysis of the effect of the scorpion toxin AaH-II on action potential generation in the axon initial segment. Sci Rep 2024; 14:4967. [PMID: 38424206 PMCID: PMC10904771 DOI: 10.1038/s41598-024-55315-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 02/22/2024] [Indexed: 03/02/2024] Open
Abstract
The toxin AaH-II, from the scorpion Androctonus australis Hector venom, is a 64 amino acid peptide that targets voltage-gated Na+ channels (VGNCs) and slows their inactivation. While at macroscopic cellular level AaH-II prolongs the action potential (AP), a functional analysis of the effect of the toxin in the axon initial segment (AIS), where VGNCs are highly expressed, was never performed so far. Here, we report an original analysis of the effect of AaH-II on the AP generation in the AIS of neocortical layer-5 pyramidal neurons from mouse brain slices. After determining that AaH-II does not discriminate between Nav1.2 and Nav1.6, i.e. between the two VGNC isoforms expressed in this neuron, we established that 7 nM was the smallest toxin concentration producing a minimal detectable deformation of the somatic AP after local delivery of the toxin. Using membrane potential imaging, we found that, at this minimal concentration, AaH-II substantially widened the AP in the AIS. Using ultrafast Na+ imaging, we found that local application of 7 nM AaH-II caused a large increase in the slower component of the Na+ influx in the AIS. Finally, using ultrafast Ca2+ imaging, we observed that 7 nM AaH-II produces a spurious slow Ca2+ influx via Ca2+-permeable VGNCs. Molecules targeting VGNCs, including peptides, are proposed as potential therapeutic tools. Thus, the present analysis in the AIS can be considered a general proof-of-principle on how high-resolution imaging techniques can disclose drug effects that cannot be observed when tested at the macroscopic level.
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Affiliation(s)
- Fatima Abbas
- Univ. Grenoble Alpes, CNRS, LIPhy, 38000, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France
| | - Laila Ananda Blömer
- Univ. Grenoble Alpes, CNRS, LIPhy, 38000, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France
| | - Hugo Millet
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France
- Nantes Université, CNRS, INSERM, l'institut du Thorax, 44000, Nantes, France
| | - Jérôme Montnach
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France
- Nantes Université, CNRS, INSERM, l'institut du Thorax, 44000, Nantes, France
| | - Michel De Waard
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France
- Nantes Université, CNRS, INSERM, l'institut du Thorax, 44000, Nantes, France
| | - Marco Canepari
- Univ. Grenoble Alpes, CNRS, LIPhy, 38000, Grenoble, France.
- Laboratories of Excellence, Ion Channel Science and Therapeutics, 06560, Valbonne, France.
- Institut National de la Santé et Recherche Médicale, Paris, France.
- Laboratoire Interdisciplinaire de Physique (UMR 5588), Bat. E45, 140 Avenue de la Physique, Domaine Univ., 38402, St Martin d'Hères Cedex, France.
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Blömer LA, Giacalone E, Abbas F, Filipis L, Tegolo D, Migliore M, Canepari M. Kinetics and functional consequences of BK channels activation by N-type Ca 2+ channels in the dendrite of mouse neocortical layer-5 pyramidal neurons. Front Cell Neurosci 2024; 18:1353895. [PMID: 38419657 PMCID: PMC10899506 DOI: 10.3389/fncel.2024.1353895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 01/24/2024] [Indexed: 03/02/2024] Open
Abstract
The back-propagation of an action potential (AP) from the axon/soma to the dendrites plays a central role in dendritic integration. This process involves an intricate orchestration of various ion channels, but a comprehensive understanding of the contribution of each channel type remains elusive. In this study, we leverage ultrafast membrane potential recordings (Vm) and Ca2+ imaging techniques to shed light on the involvement of N-type voltage-gated Ca2+ channels (VGCCs) in layer-5 neocortical pyramidal neurons' apical dendrites. We found a selective interaction between N-type VGCCs and large-conductance Ca2+-activated K+ channels (BK CAKCs). Remarkably, we observe that BK CAKCs are activated within a mere 500 μs after the AP peak, preceding the peak of the Ca2+ current triggered by the AP. Consequently, when N-type VGCCs are inhibited, the early broadening of the AP shape amplifies the activity of other VGCCs, leading to an augmented total Ca2+ influx. A NEURON model, constructed to replicate and support these experimental results, reveals the critical coupling between N-type and BK channels. This study not only redefines the conventional role of N-type VGCCs as primarily involved in presynaptic neurotransmitter release but also establishes their distinct and essential function as activators of BK CAKCs in neuronal dendrites. Furthermore, our results provide original functional validation of a physical interaction between Ca2+ and K+ channels, elucidated through ultrafast kinetic reconstruction. This insight enhances our understanding of the intricate mechanisms governing neuronal signaling and may have far-reaching implications in the field.
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Affiliation(s)
- Laila Ananda Blömer
- LIPhy, CNRS, Université Grenoble Alpes, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Elisabetta Giacalone
- Institute of Biophysics, National Research Council, Palermo, Italy
- Dipartimento Matematica e Informatica, Universitá degli Studi di Palermo, Palermo, Italy
| | - Fatima Abbas
- LIPhy, CNRS, Université Grenoble Alpes, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Luiza Filipis
- LIPhy, CNRS, Université Grenoble Alpes, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Domenico Tegolo
- Dipartimento Matematica e Informatica, Universitá degli Studi di Palermo, Palermo, Italy
| | - Michele Migliore
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Marco Canepari
- LIPhy, CNRS, Université Grenoble Alpes, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
- Institut National de la Santé et Recherche Médicale, Paris, France
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4
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Canepari M, Ross WN. Spatial and temporal aspects of neuronal calcium and sodium signals measured with low-affinity fluorescent indicators. Pflugers Arch 2024; 476:39-48. [PMID: 37798555 DOI: 10.1007/s00424-023-02865-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/12/2023] [Accepted: 09/21/2023] [Indexed: 10/07/2023]
Abstract
Low-affinity fluorescent indicators for Ca2+ or Na+ allow measuring the dynamics of intracellular concentration of these ions with little perturbation from physiological conditions because they are weak buffers. When using synthetic indicators, which are small molecules with fast kinetics, it is also possible to extract spatial and temporal information on the sources of ion transients, their localization, and their disposition. This review examines these important aspects from the biophysical point of view, and how they have been recently exploited in neurophysiological studies. We first analyze the environment where Ca2+ and Na+ indicators are inserted, highlighting the interpretation of the two different signals. Then, we address the information that can be obtained by analyzing the rising phase and the falling phase of the Ca2+ and Na+ transients evoked by different stimuli, focusing on the kinetics of ionic currents and on the spatial interpretation of these measurements, especially on events in axons and dendritic spines. Finally, we suggest how Ca2+ or Na+ imaging using low-affinity synthetic fluorescent indicators can be exploited in future fundamental or applied research.
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Affiliation(s)
- Marco Canepari
- LIPhy, CNRS, Univ. Grenoble Alpes, F-38000, Grenoble, France.
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France.
- Institut National de la Santé et Recherche Médicale, Paris, France.
| | - William N Ross
- Department of Physiology, New York Medical College, Valhalla, NY, 10595, USA
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5
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Filipis L, Canepari M. Can neuron modeling constrained by ultrafast imaging data extract the native function of ion channels? Front Comput Neurosci 2023; 17:1192421. [PMID: 37293354 PMCID: PMC10244549 DOI: 10.3389/fncom.2023.1192421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/02/2023] [Indexed: 06/10/2023] Open
Affiliation(s)
- Luiza Filipis
- Univ Grenoble Alpes, CNRS, LIPhy, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Marco Canepari
- Univ Grenoble Alpes, CNRS, LIPhy, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
- Institut National de la Santé et Recherche Médicale, Paris, France
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Ancatén-González C, Segura I, Alvarado-Sánchez R, Chávez AE, Latorre R. Ca 2+- and Voltage-Activated K + (BK) Channels in the Nervous System: One Gene, a Myriad of Physiological Functions. Int J Mol Sci 2023; 24:3407. [PMID: 36834817 PMCID: PMC9967218 DOI: 10.3390/ijms24043407] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 02/11/2023] Open
Abstract
BK channels are large conductance potassium channels characterized by four pore-forming α subunits, often co-assembled with auxiliary β and γ subunits to regulate Ca2+ sensitivity, voltage dependence and gating properties. BK channels are abundantly expressed throughout the brain and in different compartments within a single neuron, including axons, synaptic terminals, dendritic arbors, and spines. Their activation produces a massive efflux of K+ ions that hyperpolarizes the cellular membrane. Together with their ability to detect changes in intracellular Ca2+ concentration, BK channels control neuronal excitability and synaptic communication through diverse mechanisms. Moreover, increasing evidence indicates that dysfunction of BK channel-mediated effects on neuronal excitability and synaptic function has been implicated in several neurological disorders, including epilepsy, fragile X syndrome, mental retardation, and autism, as well as in motor and cognitive behavior. Here, we discuss current evidence highlighting the physiological importance of this ubiquitous channel in regulating brain function and its role in the pathophysiology of different neurological disorders.
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Affiliation(s)
- Carlos Ancatén-González
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Programa de Doctorado en Ciencias, Mención Neurociencia, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ignacio Segura
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Rosangelina Alvarado-Sánchez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
- Doctorado en Ciencias Mención Biofísica y Biología Computacional, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Andrés E. Chávez
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Instituto de Neurociencias, Universidad de Valparaíso, Valparaíso 2340000, Chile
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7
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Surdin T, Preissing B, Rohr L, Grömmke M, Böke H, Barcik M, Azimi Z, Jancke D, Herlitze S, Mark MD, Siveke I. Optogenetic activation of mGluR1 signaling in the cerebellum induces synaptic plasticity. iScience 2022; 26:105828. [PMID: 36632066 PMCID: PMC9826949 DOI: 10.1016/j.isci.2022.105828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 10/21/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Neuronal plasticity underlying cerebellar learning behavior is strongly associated with type 1 metabotropic glutamate receptor (mGluR1) signaling. Activation of mGluR1 leads to activation of the Gq/11 pathway, which is involved in inducing synaptic plasticity at the parallel fiber-Purkinje cell synapse (PF-PC) in form of long-term depression (LTD). To optogenetically modulate mGluR1 signaling we fused mouse melanopsin (OPN4) that activates the Gq/11 pathway to the C-termini of mGluR1 splice variants (OPN4-mGluR1a and OPN4-mGluR1b). Activation of both OPN4-mGluR1 variants showed robust Ca2+ increase in HEK cells and PCs of cerebellar slices. We provide the prove-of-concept approach to modulate synaptic plasticity via optogenetic activation of OPN4-mGluR1a inducing LTD at the PF-PC synapse in vitro. Moreover, we demonstrate that light activation of mGluR1a signaling pathway by OPN4-mGluR1a in PCs leads to an increase in intrinsic activity of PCs in vivo and improved cerebellum driven learning behavior.
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Affiliation(s)
- Tatjana Surdin
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Bianca Preissing
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Lennard Rohr
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Michelle Grömmke
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Hanna Böke
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Maike Barcik
- Cardiovascular Research Institute Düsseldorf, Division of Cardiology, Pulmonology, and Vascular Medicine, University Duesseldorf, Medical Faculty, Duesseldorf, Germany
| | - Zohre Azimi
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr-University Bochum, Bochum, Germany
| | - Dirk Jancke
- Optical Imaging Group, Institut für Neuroinformatik, Ruhr-University Bochum, Bochum, Germany
| | - Stefan Herlitze
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany,Corresponding author
| | - Melanie D. Mark
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Ida Siveke
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany,Bridge Institute of Experimental Tumor Therapy, West German Cancer Center, University Hospital Essen, Essen, Germany,Corresponding author
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Sato K, Saito S, Endo K, Kono M, Kakei T, Taketa H, Kato M, Hamamoto S, Grenzi M, Costa A, Munemasa S, Murata Y, Ishimaru Y, Uozumi N. Green Tea Catechins, (-)-Catechin Gallate, and (-)-Gallocatechin Gallate are Potent Inhibitors of ABA-Induced Stomatal Closure. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201403. [PMID: 35524639 PMCID: PMC9313475 DOI: 10.1002/advs.202201403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/06/2022] [Indexed: 06/04/2023]
Abstract
Stomatal movement is indispensable for plant growth and survival in response to environmental stimuli. Cytosolic Ca2+ elevation plays a crucial role in ABA-induced stomatal closure during drought stress; however, to what extent the Ca2+ movement across the plasma membrane from the apoplast to the cytosol contributes to this process still needs clarification. Here the authors identify (-)-catechin gallate (CG) and (-)-gallocatechin gallate (GCG), components of green tea, as inhibitors of voltage-dependent K+ channels which regulate K+ fluxes in Arabidopsis thaliana guard cells. In Arabidopsis guard cells CG/GCG prevent ABA-induced: i) membrane depolarization; ii) activation of Ca2+ permeable cation (ICa ) channels; and iii) cytosolic Ca2+ transients. In whole Arabidopsis plants co-treatment with CG/GCG and ABA suppressed ABA-induced stomatal closure and surface temperature increase. Similar to ABA, CG/GCG inhibited stomatal closure is elicited by the elicitor peptide, flg22 but has no impact on dark-induced stomatal closure or light- and fusicoccin-induced stomatal opening, suggesting that the inhibitory effect of CG/GCG is associated with Ca2+ -related signaling pathways. This study further supports the crucial role of ICa channels of the plasma membrane in ABA-induced stomatal closure. Moreover, CG and GCG represent a new tool for the study of abiotic or biotic stress-induced signal transduction pathways.
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Affiliation(s)
- Kanane Sato
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Shunya Saito
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Kohsuke Endo
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Masaru Kono
- Department of BiologyGraduate School of ScienceUniversity of TokyoBunkyo‐ku113‐0033Japan
| | - Taishin Kakei
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Haruka Taketa
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Megumi Kato
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Shin Hamamoto
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Matteo Grenzi
- Department of BiosciencesUniversity of MilanVia G. Celoria 26Milan20133Italy
| | - Alex Costa
- Department of BiosciencesUniversity of MilanVia G. Celoria 26Milan20133Italy
- Institute of BiophysicsNational Research Council of Italy (CNR)Via G. Celoria 26Milan20133Italy
| | - Shintaro Munemasa
- Graduate School of Environmental and Life ScienceOkayama UniversityTsushimaOkayama700‐8530Japan
| | - Yoshiyuki Murata
- Graduate School of Environmental and Life ScienceOkayama UniversityTsushimaOkayama700‐8530Japan
| | - Yasuhiro Ishimaru
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
| | - Nobuyuki Uozumi
- Department of Biomolecular EngineeringGraduate School of EngineeringTohoku UniversityAobayama 6‐6‐07Sendai980‐8579Japan
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9
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Montnach J, Blömer LA, Lopez L, Filipis L, Meudal H, Lafoux A, Nicolas S, Chu D, Caumes C, Béroud R, Jopling C, Bosmans F, Huchet C, Landon C, Canepari M, De Waard M. In vivo spatiotemporal control of voltage-gated ion channels by using photoactivatable peptidic toxins. Nat Commun 2022; 13:417. [PMID: 35058427 PMCID: PMC8776733 DOI: 10.1038/s41467-022-27974-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 12/20/2021] [Indexed: 12/11/2022] Open
Abstract
Photoactivatable drugs targeting ligand-gated ion channels open up new opportunities for light-guided therapeutic interventions. Photoactivable toxins targeting ion channels have the potential to control excitable cell activities with low invasiveness and high spatiotemporal precision. As proof-of-concept, we develop HwTxIV-Nvoc, a UV light-cleavable and photoactivatable peptide that targets voltage-gated sodium (NaV) channels and validate its activity in vitro in HEK293 cells, ex vivo in brain slices and in vivo on mice neuromuscular junctions. We find that HwTxIV-Nvoc enables precise spatiotemporal control of neuronal NaV channel function under all conditions tested. By creating multiple photoactivatable toxins, we demonstrate the broad applicability of this toxin-photoactivation technology.
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Affiliation(s)
- Jérôme Montnach
- l'institut du thorax, INSERM, CNRS, UNIV NANTES, F-44007, Nantes, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Laila Ananda Blömer
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Laboratoire Interdisciplinaire de Physique, Université Grenoble Alpes, CNRS UMR 5588, 38402, St Martin d'Hères, cedex, France
| | - Ludivine Lopez
- l'institut du thorax, INSERM, CNRS, UNIV NANTES, F-44007, Nantes, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Smartox Biotechnology, 6 rue des Platanes, F-38120, Saint-Egrève, France
| | - Luiza Filipis
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Laboratoire Interdisciplinaire de Physique, Université Grenoble Alpes, CNRS UMR 5588, 38402, St Martin d'Hères, cedex, France
| | - Hervé Meudal
- Center for Molecular Biophysics, CNRS, rue Charles Sadron, CS 80054, Orléans, 45071, France
| | - Aude Lafoux
- Therassay Platform, IRS2-Université de Nantes, Nantes, France
| | - Sébastien Nicolas
- l'institut du thorax, INSERM, CNRS, UNIV NANTES, F-44007, Nantes, France
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
| | - Duong Chu
- Queen's University Faculty of Medicine, Kingston, ON, Canada
| | - Cécile Caumes
- Smartox Biotechnology, 6 rue des Platanes, F-38120, Saint-Egrève, France
| | - Rémy Béroud
- Smartox Biotechnology, 6 rue des Platanes, F-38120, Saint-Egrève, France
| | - Chris Jopling
- Institut de Génomique Fonctionnelle, 141 rue de la Cardonille, 34094, Montpellier, France
| | - Frank Bosmans
- Department of Basic and Applied Medical Sciences, Ghent University, Ghent, Belgium
| | - Corinne Huchet
- Therassay Platform, IRS2-Université de Nantes, Nantes, France
| | - Céline Landon
- Center for Molecular Biophysics, CNRS, rue Charles Sadron, CS 80054, Orléans, 45071, France
| | - Marco Canepari
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France
- Laboratoire Interdisciplinaire de Physique, Université Grenoble Alpes, CNRS UMR 5588, 38402, St Martin d'Hères, cedex, France
| | - Michel De Waard
- l'institut du thorax, INSERM, CNRS, UNIV NANTES, F-44007, Nantes, France.
- Laboratory of Excellence Ion Channels, Science & Therapeutics, F-06560, Valbonne, France.
- Smartox Biotechnology, 6 rue des Platanes, F-38120, Saint-Egrève, France.
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Murtazina AR, Pronina TS, Chandran KI, Dilmukhametova LK, Bondarenko NS, Blokhin VE, Bogdanov VV, Ugrumov MV. Hypothesis on the Endocrine System of the Brain: Evidence for the Regulated Delivery of Neurohormones from the Brain to the Cerebrospinal Fluid and Vice Versa in Neonatal and Prepubertal Periods of Ontogenesis. Russ J Dev Biol 2021. [DOI: 10.1134/s1062360421060096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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11
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Kierzek M, Deal PE, Miller EW, Mukherjee S, Wachten D, Baumann A, Kaupp UB, Strünker T, Brenker C. Simultaneous recording of multiple cellular signaling events by frequency- and spectrally-tuned multiplexing of fluorescent probes. eLife 2021; 10:e63129. [PMID: 34859780 PMCID: PMC8700268 DOI: 10.7554/elife.63129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 12/01/2021] [Indexed: 12/21/2022] Open
Abstract
Fluorescent probes that change their spectral properties upon binding to small biomolecules, ions, or changes in the membrane potential (Vm) are invaluable tools to study cellular signaling pathways. Here, we introduce a novel technique for simultaneous recording of multiple probes at millisecond time resolution: frequency- and spectrally-tuned multiplexing (FASTM). Different from present multiplexing approaches, FASTM uses phase-sensitive signal detection, which renders various combinations of common probes for Vm and ions accessible for multiplexing. Using kinetic stopped-flow fluorimetry, we show that FASTM allows simultaneous recording of rapid changes in Ca2+, pH, Na+, and Vm with high sensitivity and minimal crosstalk. FASTM is also suited for multiplexing using single-cell microscopy and genetically encoded FRET biosensors. Moreover, FASTM is compatible with optochemical tools to study signaling using light. Finally, we show that the exceptional time resolution of FASTM also allows resolving rapid chemical reactions. Altogether, FASTM opens new opportunities for interrogating cellular signaling.
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Affiliation(s)
- Michelina Kierzek
- Centre of Reproductive Medicine and Andrology, University of MünsterMünsterGermany
- CiM-IMPRS Graduate School, University of MünsterMünsterGermany
| | - Parker E Deal
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
| | - Evan W Miller
- Department of Chemistry, University of California, BerkeleyBerkeleyUnited States
- Department of Molecular & Cell Biology, University of California, BerkeleyBerkeleyUnited States
- Helen Wills Neuroscience Institute, University of California, BerkeleyBerkeleyUnited States
| | - Shatanik Mukherjee
- Molecular Sensory Systems, Center of Advanced European Studies and ResearchBonnGermany
| | - Dagmar Wachten
- Institute of Innate Immunity, Department of Biophysical Imaging, Medical Faculty, University of BonnBonnGermany
| | - Arnd Baumann
- Institute of Biological Information Processing (IBI-1), Research Center JülichJülichGermany
| | - U Benjamin Kaupp
- Life & Medical Sciences Institute (LIMES), University of BonnBonnGermany
| | - Timo Strünker
- Centre of Reproductive Medicine and Andrology, University of MünsterMünsterGermany
- Cells in Motion Interfaculty Centre, University of MünsterMünsterGermany
| | - Christoph Brenker
- Centre of Reproductive Medicine and Andrology, University of MünsterMünsterGermany
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12
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Benarroch E. What Is the Role of Potassium Channels in Ataxia? Neurology 2021; 97:938-941. [PMID: 34782409 DOI: 10.1212/wnl.0000000000012870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 11/15/2022] Open
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13
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Blömer LA, Filipis L, Canepari M. Cal-520FF is the Present Optimal Ca 2+ Indicator for Ultrafast Ca 2+ Imaging and Optical Measurement of Ca 2+ Currents. J Fluoresc 2021; 31:619-623. [PMID: 33606130 DOI: 10.1007/s10895-021-02701-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Accepted: 02/11/2021] [Indexed: 11/29/2022]
Abstract
Ultrafast Ca2+ imaging using low-affinity fluorescent indicators allows the precise measurement of the kinetics of fast Ca2+ currents mediated by voltage-gated Ca2+ channels. Thus far, only a few indicators provided fluorescence transients with sufficient signal-to-noise ratio necessary to achieve this measurement, with Oregon Green BAPTA-5N exhibiting the best performance. Here we evaluated the performance of the low-affinity Ca2+ indicator Cal-520FF to record fast Ca2+ signals and to measure the kinetics of Ca2+ currents. Compared to Oregon Green BAPTA-5N and to Fluo4FF, Cal-520FF offers a superior signal-to-noise-ratio providing the optimal characteristics for this important type of biophysical measurement. This ability is the result of a relatively high fluorescence at zero Ca2+, necessary to detect enough photons at short exposure windows, and a high dynamic range leading to large fluorescence transients associated with short Ca2+ influx periods. We conclude that Cal-520FF is at present the optimal commercial low-affinity Ca2+ indicator for ultrafast Ca2+ imaging applications.
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Affiliation(s)
- Laila Ananda Blömer
- University Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Luiza Filipis
- University Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France
| | - Marco Canepari
- University Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France.
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France.
- Institut National de la Santé et Recherche Médicale, Paris, France.
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14
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Blömer LA, Canepari M, Filipis L. Ultrafast Sodium Imaging of the Axon Initial Segment of Neurons in Mouse Brain Slices. Curr Protoc 2021; 1:e64. [PMID: 33657273 DOI: 10.1002/cpz1.64] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Monitoring Na+ influx in the axon initial segment (AIS) at high spatial and temporal resolution is fundamental to understanding the generation of an action potential (AP). Here, we present protocols to obtain this measurement, focusing on the AIS of layer 5 (L5) somatosensory cortex pyramidal neurons in mouse brain slices. We first outline how to prepare slices for this application, how to select and patch neurons, and how to optimize the image acquisition. Specifically, we describe the preparation of optimal slices, patching and loading of L5 pyramidal neurons with the Na+ indicator ING-2, and Na+ imaging at 100 µs temporal resolution with a pixel resolution of half a micron. Then, we present a data analysis strategy in order to extract information on the kinetics of activated voltage-gated Na+ channels by determining the change in Na+ by compensating for bleaching and calculating the time derivative of the resulting fit. In sum, this approach can be widely applied when investigating the function of Na+ channels during initiation of an AP and propagation under physiological or pathological conditions in neuronal subtypes. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Preparation of cortical slices Basic Protocol 2: Selection, patching, and Na+ fluorescence recording of a neuron Support Protocol: Calibrating Na+ fluorescence Basic Protocol 3: Data analysis.
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Affiliation(s)
- Laila Ananda Blömer
- Université Grenoble Alpes, CNRS, LIPhy, Grenoble, France.,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbone, France
| | - Marco Canepari
- Université Grenoble Alpes, CNRS, LIPhy, Grenoble, France.,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbone, France.,Institut National de la Santé et Recherche Médicale, Paris, France
| | - Luiza Filipis
- Université Grenoble Alpes, CNRS, LIPhy, Grenoble, France.,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbone, France
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15
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Zheng Y, Xia P, Dong L, Tian L, Xiong C. Effects of modulation on sodium and potassium channel currents by extremely low frequency electromagnetic fields stimulation on hippocampal CA1 pyramidal cells. Electromagn Biol Med 2021; 40:274-285. [PMID: 33594919 DOI: 10.1080/15368378.2021.1885433] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
To investigate the effects of extremely low-frequency electromagnetic fields (ELF-EMFs) stimulation on sodium channel currents (INa), transient outward potassium channel currents (IA) and delayed rectifier potassium channel currents (IK) on hippocampal CA1 pyramidal neurons of young Sprague-Dawley rats. CA1 pyramidal neurons of rat hippocampal slices were subjected to ELF-EMFs stimulation with different frequencies (15 and 50 Hz), intensities (0.5, 1 and 2 mT) and durations (10, 20 and 30 min). The INa, IA and IK of neurons were recorded by a whole-cell patch-clamp method. ELF-EMFs stimulation enhanced INa densities, and depressed IA and IK densities. In detail, INa was more sensitive to the variation of intensities and frequencies of ELF-EMFs, whereas IA and IK were mainly affected by the variation of the duration of ELF-EMFs. ELF-EMFs stimulation altered activation and deactivation properties of INa, IA and IK. ELF-EMFs stimulation plays a role as a regulator rather than an inducer for ion channels. It might change the transition probability of ion channel opening or closing, and might also change the structure and function of the ion channel which need to be proved by the further technical method.
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Affiliation(s)
- Yu Zheng
- School of Life Sciences, Tiangong University, Tianjin, China
| | - Pei Xia
- School of Life Sciences, Tiangong University, Tianjin, China
| | - Lei Dong
- State Key Laboratory of Precision Measurement Technology and Instruments, Tianjin University, Tianjin, China
| | - Lei Tian
- School of Life Sciences, Tiangong University, Tianjin, China
| | - Chan Xiong
- The Department of Chemistry, University of Graz, Universitaetplatz, Graz, Austria
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16
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BK Channel Regulation of Afterpotentials and Burst Firing in Cerebellar Purkinje Neurons. J Neurosci 2021; 41:2854-2869. [PMID: 33593855 DOI: 10.1523/jneurosci.0192-20.2021] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 01/13/2021] [Accepted: 02/05/2021] [Indexed: 11/21/2022] Open
Abstract
BK calcium-activated potassium channels have complex kinetics because they are activated by both voltage and cytoplasmic calcium. The timing of BK activation and deactivation during action potentials determines their functional role in regulating firing patterns but is difficult to predict a priori. We used action potential clamp to characterize the kinetics of voltage-dependent calcium current and BK current during action potentials in Purkinje neurons from mice of both sexes, using acutely dissociated neurons that enabled rapid voltage clamp at 37°C. With both depolarizing voltage steps and action potential waveforms, BK current was entirely dependent on calcium entry through voltage-dependent calcium channels. With voltage steps, BK current greatly outweighed the triggering calcium current, with only a brief, small net inward calcium current before Ca-activated BK current dominated the total Ca-dependent current. During action potential waveforms, although BK current activated with only a short (∼100 μs) delay after calcium current, the two currents were largely separated, with calcium current flowing during the falling phase of the action potential and most BK current flowing over several milliseconds after repolarization. Step depolarizations activated both an iberiotoxin-sensitive BK component with rapid activation and deactivation kinetics and a slower-gating iberiotoxin-resistant component. During action potential firing, however, almost all BK current came from the faster-gating iberiotoxin-sensitive channels, even during bursts of action potentials. Inhibiting BK current had little effect on action potential width or a fast afterhyperpolarization but converted a medium afterhyperpolarization to an afterdepolarization and could convert tonic firing of single action potentials to burst firing.SIGNIFICANCE STATEMENT BK calcium-activated potassium channels are widely expressed in central neurons. Altered function of BK channels is associated with epilepsy and other neuronal disorders, including cerebellar ataxia. The functional role of BK in regulating neuronal firing patterns is highly dependent on the context of other channels and varies widely among different types of neurons. Most commonly, BK channels are activated during action potentials and help produce a fast afterhyperpolarization. We find that in Purkinje neurons BK current flows primarily after the fast afterhyperpolarization and helps to prevent a later afterdepolarization from producing rapid burst firing, enabling typical regular tonic firing.
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17
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Filipis L, Canepari M. Optical measurement of physiological sodium currents in the axon initial segment. J Physiol 2020; 599:49-66. [PMID: 33094478 DOI: 10.1113/jp280554] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/16/2020] [Indexed: 01/06/2023] Open
Abstract
KEY POINTS Τhe axonal Na+ fluorescence underlying an action potential in the axon initial segment was optically measured at unprecedented temporal resolution. The measurement allowed resolution of the kinetics of the Na+ current at different axonal locations. The distinct components of the Na+ current were correlated with the kinetics of the action potential. NEURON simulations from a modified published model qualitatively predicted the experimentally measured Na+ current. The present method permits the direct investigation of the kinetic behaviour of native Na+ channels under physiological and pathological conditions. ABSTRACT In most neurons of the mammalian central nervous system, the action potential (AP) is generated in the axon initial segment (AIS) by a fast Na+ current mediated by voltage-gated Na+ channels. While the axonal Na+ signal associated with the AP has been measured using fluorescent Na+ indicators, the insufficient resolution of these recordings has not allowed tracking the Na+ current kinetics underlying this fundamental event. In this article, we report the first optical measurement of Na+ currents in the AIS of pyramidal neurons of layer 5 of the somatosensory cortex from brain slices of the mouse. This measurement was obtained by achieving a temporal resolution of 100 μs in the Na+ imaging technique, with a pixel resolution of 0.5 μm, and by calculating the time-derivative of the Na+ change corrected for longitudinal diffusion. We identified a subthreshold current before the AP, a fast-inactivating current peaking during the rise of the AP and a non-inactivating current during the AP repolarization. We established a correlation between the kinetics of the non-inactivating current at different distances from the soma and the kinetics of the somatic AP. We quantitatively compared the experimentally measured Na+ current with the current obtained by computer simulation of published NEURON models, demonstrating how the present approach can lead to the correct estimate of the native behaviour of Na+ channels. Finally, we discuss how the present approach can be used to investigate the physiological or pathological function of different channel types during AP initiation and propagation.
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Affiliation(s)
- Luiza Filipis
- University of Grenoble Alpes, CNRS, LIPhy, Grenoble, F38000, France.,Laboratories of Excellence, Ion Channel Science and Therapeutics, France
| | - Marco Canepari
- University of Grenoble Alpes, CNRS, LIPhy, Grenoble, F38000, France.,Laboratories of Excellence, Ion Channel Science and Therapeutics, France.,Institut National de la Santé et Recherche Médicale, France
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18
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Canepari M. Is Purkinje Neuron Hyperpolarisation Important for Cerebellar Synaptic Plasticity? A Retrospective and Prospective Analysis. THE CEREBELLUM 2020; 19:869-878. [PMID: 32654026 DOI: 10.1007/s12311-020-01164-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two recent studies have demonstrated that the dendritic Ca2+ signal associated with a climbing fibre (CF) input to the cerebellar Purkinje neuron (PN) depends on the membrane potential (Vm). Specifically, when the cell is hyperpolarised, this signal is mediated by T-type voltage-gated Ca2+ channels; in contrast, when the cell is firing, the CF-PN signal is mediated by P/Q-type voltage-gated Ca2+ channels. When the CF input is paired with parallel fibre (PF) activity, the signal is locally amplified at the sites of PF-activated synapses according to the Vm at the time of the CF input, suggesting that the standing Vm is a critical parameter for the induction of PF synaptic plasticity. In this review, I analyse how the Vm can potentially play a role in cerebellar learning focussing, in particular, on the hyperpolarised state that appears to occur episodically, since PNs are mostly firing under physiological conditions. By revisiting the recent literature reporting in vivo recordings and synaptic plasticity studies, I speculate on how a putative role of the PN Vm can provide an interpretation for the results of these studies.
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Affiliation(s)
- Marco Canepari
- University of Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France. .,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France. .,Institut National de la Santé et Recherche Médicale, Paris, France.
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19
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The Origin of Physiological Local mGluR1 Supralinear Ca 2+ Signals in Cerebellar Purkinje Neurons. J Neurosci 2020; 40:1795-1809. [PMID: 31969470 DOI: 10.1523/jneurosci.2406-19.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 01/09/2020] [Accepted: 01/11/2020] [Indexed: 11/21/2022] Open
Abstract
In mouse cerebellar Purkinje neurons (PNs), the climbing fiber (CF) input provides a signal to parallel fiber (PF) synapses, triggering PF synaptic plasticity. This signal is given by supralinear Ca2+ transients, associated with the CF synaptic potential and colocalized with the PF Ca2+ influx, occurring only when PF activity precedes the CF input. Here, we unravel the biophysical determinants of supralinear Ca2+ signals associated with paired PF-CF synaptic activity. We used membrane potential (V m) and Ca2+ imaging to investigate the local CF-associated Ca2+ influx following a train of PF synaptic potentials in two cases: (1) when the dendritic V m is hyperpolarized below the resting V m, and (2) when the dendritic V m is at rest. We found that supralinear Ca2+ signals are mediated by type-1 metabotropic glutamate receptors (mGluR1s) when the CF input is delayed by 100-150 ms from the first PF input in both cases. When the dendrite is hyperpolarized only, however, mGluR1s boost neighboring T-type channels, providing a mechanism for local coincident detection of PF-CF activity. The resulting Ca2+ elevation is locally amplified by saturation of endogenous Ca2+ buffers produced by the PF-associated Ca2+ influx via the mGluR1-mediated nonselective cation conductance. In contrast, when the dendritic V m is at rest, mGluR1s increase dendritic excitability by inactivating A-type K+ channels, but this phenomenon is not restricted to the activated PF synapses. Thus, V m is likely a crucial parameter in determining PF synaptic plasticity, and the occurrence of hyperpolarization episodes is expected to play an important role in motor learning.SIGNIFICANCE STATEMENT In Purkinje neurons, parallel fiber synaptic plasticity, determined by coincident activation of the climbing fiber input, underlies cerebellar learning. We unravel the biophysical mechanisms allowing the CF input to produce a local Ca2+ signal exclusively at the sites of activated parallel fibers. We show that when the membrane potential is hyperpolarized with respect to the resting membrane potential, type-1 metabotropic glutamate receptors locally enhance Ca2+ influx mediated by T-type Ca2+ channels, and that this signal is amplified by saturation of endogenous buffer also mediated by the same receptors. The combination of these two mechanisms is therefore capable of producing a Ca2+ signal at the activated parallel fiber sites, suggesting a role of Purkinje neuron membrane potential in cerebellar learning.
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20
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Antic SD, Baker BJ, Canepari M. Editorial: New Insights on Neuron and Astrocyte Function From Cutting-Edge Optical Techniques. Front Cell Neurosci 2019; 13:463. [PMID: 31680872 PMCID: PMC6803618 DOI: 10.3389/fncel.2019.00463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 09/30/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Srdjan D Antic
- Department of Neuroscience, Institute for Systems Genomics, Stem Cell Institute, UConn Health, Farmington, CT, United States
| | - Bradley James Baker
- The Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul, South Korea
| | - Marco Canepari
- Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology (UST), Seoul, South Korea.,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France.,Institut National de la Santé et Recherche Médicale, Paris, France
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