β-cell deletion of the PKm1 and PKm2 isoforms of pyruvate kinase in mice reveal their essential role as nutrient sensors for the KATP channel

  1. Hannah R Foster
  2. Thuong Ho
  3. Evgeniy Potapenko
  4. Sophia M Sdao
  5. Shih Ming Huang
  6. Sophie L Lewandowski
  7. Halena R VanDeusen
  8. Shawn M Davidson
  9. Rebecca L Cardone
  10. Marc Prentki
  11. Richard G Kibbey
  12. Matthew J Merrins  Is a corresponding author
  1. University of Wisconsin-Madison, United States
  2. Massachusetts Institute of Technology, United States
  3. Yale University, United States
  4. University of Montreal, Canada

Abstract

Pyruvate kinase (PK) and the phosphoenolpyruvate (PEP) cycle play key roles in nutrient-stimulated KATP channel closure and insulin secretion. To identify the PK isoforms involved, we generated mice lacking β-cell PKm1, PKm2, and mitochondrial PEP carboxykinase (PCK2) that generates mitochondrial PEP. Glucose metabolism generates both glycolytic and mitochondrially-derived PEP, which triggers KATP closure through local PKm1 and PKm2 signaling at the plasma membrane. Amino acids, which generate mitochondrial PEP without producing glycolytic fructose 1,6-bisphosphate to allosterically activate PKm2, signal through PKm1 to raise ATP/ADP, close KATP channels, and stimulate insulin secretion. Raising cytosolic ATP/ADP with amino acids is insufficient to close KATP channels in the absence of PK activity or PCK2, indicating that KATP channels are primarily regulated by PEP that provides ATP via plasma membrane-associated PK, rather than mitochondrially-derived ATP. Following membrane depolarization, the PEP cycle is also involved in an 'off-switch' that facilitates KATP channel reopening and Ca2+ extrusion, as shown by PK activation experiments and β-cell PCK2 deletion, which prolongs Ca2+ oscillations and increases insulin secretion. In conclusion, the differential response of PKm1 and PKm2 to the glycolytic and mitochondrial sources of PEP influences the β-cell nutrient response, and controls the oscillatory cycle regulating insulin secretion.

Data availability

Datasets generated or analyzed in this study are included in the manuscript and supporting files. Source data files are provided for Figures 1-6 and the associated figure supplement files.

Article and author information

Author details

  1. Hannah R Foster

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Thuong Ho

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Evgeniy Potapenko

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Sophia M Sdao

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Shih Ming Huang

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Sophie L Lewandowski

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Halena R VanDeusen

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Shawn M Davidson

    Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Rebecca L Cardone

    Department of Internal Medicine, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Marc Prentki

    Department of Nutrition, University of Montreal, Montreal, Canada
    Competing interests
    The authors declare that no competing interests exist.
  11. Richard G Kibbey

    Department of Internal Medicine, Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. Matthew J Merrins

    Department of Medicine, University of Wisconsin-Madison, Madison, United States
    For correspondence
    merrins@wisc.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1599-9227

Funding

National Institutes of Health (R01DK113103)

  • Matthew J Merrins

National Institutes of Health (R01DK113103)

  • Matthew J Merrins

U.S. Department of Veterans Affairs (I01B005113)

  • Matthew J Merrins

Health Resources and Services Administration (T32HP10010)

  • Hannah R Foster

National Institutes of Health (T32AG000213)

  • Hannah R Foster

National Institutes of Health (T32DK007665)

  • Sophie L Lewandowski

American Diabetes Association (1-17-PDF-155)

  • Halena R VanDeusen

National Institutes of Health (R01AG062328)

  • Matthew J Merrins

National Institutes of Health (R01DK127637)

  • Richard G Kibbey

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

Ethics

Animal experimentation: Animal experiments were conducted under the supervision of the IACUC of the William S. Middleton Memorial Veterans Hospital (Protocol: MJM0001).

Reviewing Editor

  1. Lori Sussel, University of Colorado Anschutz Medical Campus, United States

Publication history

  1. Preprint posted: February 10, 2022 (view preprint)
  2. Received: April 12, 2022
  3. Accepted: August 23, 2022
  4. Accepted Manuscript published: August 23, 2022 (version 1)
  5. Version of Record published: September 5, 2022 (version 2)

Copyright

© 2022, Foster 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. Hannah R Foster
  2. Thuong Ho
  3. Evgeniy Potapenko
  4. Sophia M Sdao
  5. Shih Ming Huang
  6. Sophie L Lewandowski
  7. Halena R VanDeusen
  8. Shawn M Davidson
  9. Rebecca L Cardone
  10. Marc Prentki
  11. Richard G Kibbey
  12. Matthew J Merrins
(2022)
β-cell deletion of the PKm1 and PKm2 isoforms of pyruvate kinase in mice reveal their essential role as nutrient sensors for the KATP channel
eLife 11:e79422.
https://doi.org/10.7554/eLife.79422

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