Tonic inhibition of the chloride/proton antiporter ClC-7 by PI(3,5)P2 is crucial for lysosomal pH maintenance

  1. Xavier Leray
  2. Jacob K Hilton
  3. Kamsi Nwangwu
  4. Alissa Becerril
  5. Vedrana Mikusevic
  6. Gabriel Fitzgerald
  7. Anowarul Amin
  8. Mary R Weston
  9. Joseph A Mindell  Is a corresponding author
  1. National Institute of Neurological Disorders and Stroke, United States

Abstract

The acidic luminal pH of lysosomes, maintained within a narrow range, is essential for proper degrative function of the organelle and is generated by the action of a V-type H+ ATPase, but other pathways for ion movement are required to dissipate the voltage generated by this process. ClC-7, a Cl-/H+ antiporter responsible for lysosomal Cl- permeability, is a candidate to contribute to the acidification process as part of this 'counterion pathway'. The signaling lipid PI(3,5)P2 modulates lysosomal dynamics, including by regulating lysosomal ion channels, raising the possibility that it could contribute to lysosomal pH regulation. Here we demonstrate that depleting PI(3,5)P2 by inhibiting the PIKfyve kinase causes lysosomal hyperacidification, primarily via an effect on ClC-7. We further show that PI(3,5)P2 directly inhibits ClC-7 transport and that this inhibition is eliminated in a disease-causing gain-of-function ClC-7 mutation. Together these observations suggest an intimate role for ClC-7 in lysosomal pH regulation.

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All analyzed data are included in the manuscript

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Author details

  1. Xavier Leray

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2107-6082
  2. Jacob K Hilton

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1931-9516
  3. Kamsi Nwangwu

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3446-8539
  4. Alissa Becerril

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Vedrana Mikusevic

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9666-9571
  6. Gabriel Fitzgerald

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Anowarul Amin

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Mary R Weston

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Joseph A Mindell

    Membrane Transport Biophysics Section, National Institute of Neurological Disorders and Stroke, Bethesda, United States
    For correspondence
    mindellj@ninds.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6952-8247

Funding

National Institute of Neurological Disorders and Stroke

  • Xavier Leray
  • Jacob K Hilton
  • Kamsi Nwangwu
  • Alissa Becerril
  • Vedrana Mikusevic
  • Gabriel Fitzgerald
  • Anowarul Amin
  • Mary R Weston
  • Joseph A Mindell

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: September 23, 2021
  2. Preprint posted: October 7, 2021 (view preprint)
  3. Accepted: June 6, 2022
  4. Accepted Manuscript published: June 7, 2022 (version 1)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Xavier Leray
  2. Jacob K Hilton
  3. Kamsi Nwangwu
  4. Alissa Becerril
  5. Vedrana Mikusevic
  6. Gabriel Fitzgerald
  7. Anowarul Amin
  8. Mary R Weston
  9. Joseph A Mindell
(2022)
Tonic inhibition of the chloride/proton antiporter ClC-7 by PI(3,5)P2 is crucial for lysosomal pH maintenance
eLife 11:e74136.
https://doi.org/10.7554/eLife.74136

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