Probing the ionotropic activity of glutamate GluD2 receptor in HEK cells with genetically-engineered photopharmacology

  1. Damien Lemoine
  2. Sarah Mondoloni
  3. Jérome Tange
  4. Bertrand Lambolez
  5. Philippe Faure
  6. Antoine Taly
  7. Ludovic Tricoire  Is a corresponding author
  8. Alexandre Mourot  Is a corresponding author
  1. Sorbonne Université, INSERM, CNRS, France
  2. Institut de Biologie Physico-chimique, France

Abstract

Glutamate delta (GluD) receptors belong to the ionotropic glutamate receptor family, yet they don't bind glutamate and are considered orphan. Progress in defining the ion channel function of GluDs in neurons has been hindered by a lack of pharmacological tools. Here we used a chemo-genetic approach to engineer specific and photo-reversible pharmacology in GluD2 receptor. We incorporated a cysteine mutation in the cavity located above the putative ion channel pore, for site-specific conjugation with a photoswitchable pore blocker. In the constitutively-open GluD2 Lurcher mutant, current could be rapidly and reversibly decreased with light. We then transposed the cysteine mutation to the native receptor, to demonstrate with high pharmacological specificity that metabotropic glutamate receptor signaling triggers opening of GluD2. Our results assess the functional relevance of GluD2 ion channel and introduce an optogenetic tool that will provide a novel and powerful means for probing GluD2 ionotropic contribution to neuronal physiology.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Source data have been provided for all the figures.

Article and author information

Author details

  1. Damien Lemoine

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Sarah Mondoloni

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Jérome Tange

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  4. Bertrand Lambolez

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0653-480X
  5. Philippe Faure

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3573-4971
  6. Antoine Taly

    Laboratoire de Biochimie Théorique, Institut de Biologie Physico-chimique, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5109-0091
  7. Ludovic Tricoire

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    For correspondence
    ludovic.tricoire@upmc.fr
    Competing interests
    The authors declare that no competing interests exist.
  8. Alexandre Mourot

    Neuroscience Paris Seine - Institut de Biologie Paris Seine (NPS - IBPS), Sorbonne Université, INSERM, CNRS, Paris, France
    For correspondence
    alexandre.mourot@inserm.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8839-7481

Funding

Agence Nationale de la Recherche (ANR-16-CE16-0014-01)

  • Ludovic Tricoire

Fondation pour la Recherche Médicale (FRM EQU201903007961)

  • Philippe Faure

LABEX Dynamo

  • Antoine Taly

Agence Nationale de la Recherche (ANR-11-LABX-0011)

  • Antoine Taly

LABEX Biopsy

  • Damien Lemoine

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

Reviewing Editor

  1. Merritt Maduke, Stanford University School of Medicine, United States

Publication history

  1. Received: May 19, 2020
  2. Accepted: October 27, 2020
  3. Accepted Manuscript published: October 28, 2020 (version 1)
  4. Version of Record published: November 20, 2020 (version 2)

Copyright

© 2020, Lemoine 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. Damien Lemoine
  2. Sarah Mondoloni
  3. Jérome Tange
  4. Bertrand Lambolez
  5. Philippe Faure
  6. Antoine Taly
  7. Ludovic Tricoire
  8. Alexandre Mourot
(2020)
Probing the ionotropic activity of glutamate GluD2 receptor in HEK cells with genetically-engineered photopharmacology
eLife 9:e59026.
https://doi.org/10.7554/eLife.59026

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