A highly responsive pyruvate sensor reveals pathway-regulatory role of the mitochondrial pyruvate carrier MPC

  1. Robinson Arce-Molina
  2. Francisca Cortés-Molina
  3. Pamela Y Sandoval
  4. Alex Galaz
  5. Karin Alegría
  6. Stefanie Schirmeier
  7. L Felipe Barros  Is a corresponding author
  8. Alejandro San Martín  Is a corresponding author
  1. Center for Scientific Studies - CECs, Chile
  2. University of Münster, Germany

Abstract

Mitochondria generate ATP and building blocks for cell growth and regeneration, using pyruvate as the main substrate. Here we introduce PyronicSF, a user-friendly GFP-based sensor of improved dynamic range that enables real-time subcellular quantitation of mitochondrial pyruvate transport, concentration and flux. We report that cultured mouse astrocytes maintain mitochondrial pyruvate in the low micromolar range, below cytosolic pyruvate, which means that the mitochondrial pyruvate carrier MPC is poised to exert ultrasensitive control on the balance between respiration and anaplerosis/gluconeogenesis. The functionality of the sensor in living tissue is demonstrated in the brain of Drosophila melanogaster larvae. Mitochondrial subpopulations are known to coexist within a given cell, which differ in their morphology, mobility, membrane potential, and vicinity to other organelles. The present tool can be used to investigate how mitochondrial diversity relates to metabolism, to study the role of MPC in disease, and to screen for small-molecule MPC modulators.

Data availability

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

Article and author information

Author details

  1. Robinson Arce-Molina

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    Competing interests
    The authors declare that no competing interests exist.
  2. Francisca Cortés-Molina

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    Competing interests
    The authors declare that no competing interests exist.
  3. Pamela Y Sandoval

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    Competing interests
    The authors declare that no competing interests exist.
  4. Alex Galaz

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    Competing interests
    The authors declare that no competing interests exist.
  5. Karin Alegría

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    Competing interests
    The authors declare that no competing interests exist.
  6. Stefanie Schirmeier

    Institut für Neuro- und Verhaltensbiologie, University of Münster, Münster, Germany
    Competing interests
    The authors declare that no competing interests exist.
  7. L Felipe Barros

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    For correspondence
    fbarros@cecs.cl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6623-4833
  8. Alejandro San Martín

    Biology, Center for Scientific Studies - CECs, Valdivia, Chile
    For correspondence
    aalejo@cecs.cl
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5608-5117

Funding

Fondo Nacional de Desarrollo Científico y Tecnológico (11150930)

  • Alejandro San Martín

Fondo Nacional de Desarrollo Científico y Tecnológico (1160317)

  • L Felipe Barros

CONICYT CHILE (PB-01)

  • L Felipe Barros

Deutsche Forschungsgemeinschaft (SFB1009)

  • Stefanie Schirmeier

Deutsche Forschungsgemeinschaft (SCHI 1380/2)

  • Stefanie Schirmeier

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

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. Procedures were approved by the Centro de Estudios Científicos Animal Care and Use Committee, project 1160317.

Reviewing Editor

  1. David E James, The University of Sydney, Australia

Publication history

  1. Received: November 24, 2019
  2. Accepted: March 5, 2020
  3. Accepted Manuscript published: March 6, 2020 (version 1)
  4. Version of Record published: March 17, 2020 (version 2)

Copyright

© 2020, Arce-Molina 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. Robinson Arce-Molina
  2. Francisca Cortés-Molina
  3. Pamela Y Sandoval
  4. Alex Galaz
  5. Karin Alegría
  6. Stefanie Schirmeier
  7. L Felipe Barros
  8. Alejandro San Martín
(2020)
A highly responsive pyruvate sensor reveals pathway-regulatory role of the mitochondrial pyruvate carrier MPC
eLife 9:e53917.
https://doi.org/10.7554/eLife.53917

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