β2-subunit alternative splicing stabilizes Cav2.3 Ca2+ channel activity during continuous midbrain dopamine neuron-like activity

Abstract

In dopaminergic (DA) substantia nigra (SN) neurons Cav2.3 R-type Ca2+-currents contribute to somatodendritic Ca2+-oscillations. This activity may contribute to the selective degeneration of these neurons in Parkinson's disease (PD) since Cav2.3-knockout is neuroprotective in a PD mouse model. Here we show that in tsA-201-cells the membrane-anchored β2-splice variants β2a and β2e are required to stabilize Cav2.3 gating properties allowing sustained Cav2.3 availability during simulated pacemaking and enhanced Ca2+-currents during bursts. We confirmed the expression of β2a- and β2e-subunit transcripts in the mouse SN and in identified SN DA neurons. Patch-clamp recordings of mouse DA midbrain neurons in culture and SN DA neurons in brain slices revealed SNX-482-sensitive R-type Ca2+-currents with voltage-dependent gating properties that suggest modulation by β2a- and/or β2e-subunits. Thus, β-subunit alternative splicing may prevent a fraction of Cav2.3 channels from inactivation in continuously active, highly vulnerable SN DA neurons, thereby also supporting Ca2+ signals contributing to the (patho)physiological role of Cav2.3 channels in PD.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files. Raw data have been provided for mean population data shown in Figures and Tables.

The following previously published data sets were used

Article and author information

Author details

  1. Anita Siller

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
  2. Nadja T Hofer

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
  3. Giulia Tomagra

    Department of Drug Science, University of Torino, Torino, Italy
    Competing interests
    The authors declare that no competing interests exist.
  4. Nicole Wiederspohn

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Simon Hess

    Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Julia Benkert

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. Aisylu Gaifullina

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. Desiree Spaich

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  9. Johanna Duda

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Christina Poetschke

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  11. Kristina Vilusic

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
  12. Eva Maria Fritz

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    Competing interests
    The authors declare that no competing interests exist.
  13. Toni Schneider

    Institute of Neurophysiology, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  14. Peter Kloppenburg

    Institute for Zoology, Biocenter, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4554-404X
  15. Birgit Liss

    Institute of Applied Physiology, University of Ulm, Ulm, Germany
    Competing interests
    The authors declare that no competing interests exist.
  16. Valentina Carabelli

    Department of Drug Science, University of Torino, Torino, Italy
    Competing interests
    The authors declare that no competing interests exist.
  17. Emilio Carbone

    Department of Drug Science, University of Torino, Torino, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2239-6280
  18. Nadine Jasmin Ortner

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    For correspondence
    nadine.ortner@uibk.ac.at
    Competing interests
    The authors declare that no competing interests exist.
  19. Jörg Striessnig

    Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
    For correspondence
    joerg.striessnig@uibk.ac.at
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9406-7120

Funding

Austrian Science Fund (P27809,P35722,CavX-DOC 30 doc.fund)

  • Jörg Striessnig

Tyrolean Science Fund (UNI-0404/2345)

  • Nadine Jasmin Ortner

Italian Miur (2015FNWP34)

  • Emilio Carbone

Compagnia di San Paolo (CSTO165284)

  • Emilio Carbone

Austrian Science Fund (P35087)

  • Nadine Jasmin Ortner

Hamburg Institute for Advanced Study (Research Fellowship)

  • Birgit Liss

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Henry M Colecraft, Columbia University, United States

Ethics

Animal experimentation: All animal experiments and procedures were performed in strict accordance with the European Community's Council Directive 2010/63/UE and approved by the Italian Ministry of Health and the Local Organism responsible for animal welfare at the University of Torino (authorization DGSAF 0011710-P-26/07/2017) and the local authorities at the University of Ulm (Regierungspräsidium Tübingen, Ref: 35/9185.81-3; Reg. Nr. o.147) and University of Cologne (LANUV NRW, Recklinghausen, Germany (84-02.05.20.12.254).

Version history

  1. Preprint posted: February 10, 2021 (view preprint)
  2. Received: February 11, 2021
  3. Accepted: July 4, 2022
  4. Accepted Manuscript published: July 6, 2022 (version 1)
  5. Accepted Manuscript updated: July 8, 2022 (version 2)
  6. Version of Record published: July 22, 2022 (version 3)
  7. Version of Record updated: July 27, 2022 (version 4)

Copyright

© 2022, Siller et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Anita Siller
  2. Nadja T Hofer
  3. Giulia Tomagra
  4. Nicole Wiederspohn
  5. Simon Hess
  6. Julia Benkert
  7. Aisylu Gaifullina
  8. Desiree Spaich
  9. Johanna Duda
  10. Christina Poetschke
  11. Kristina Vilusic
  12. Eva Maria Fritz
  13. Toni Schneider
  14. Peter Kloppenburg
  15. Birgit Liss
  16. Valentina Carabelli
  17. Emilio Carbone
  18. Nadine Jasmin Ortner
  19. Jörg Striessnig
(2022)
β2-subunit alternative splicing stabilizes Cav2.3 Ca2+ channel activity during continuous midbrain dopamine neuron-like activity
eLife 11:e67464.
https://doi.org/10.7554/eLife.67464

Share this article

https://doi.org/10.7554/eLife.67464

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