Z-REX uncovers a bifurcation in function of Keap1 paralogs

  1. Alexandra Van Hall-Beauvais
  2. Jesse R Poganik
  3. Kuan-Ting Huang
  4. Saba Parvez
  5. Yi Zhao
  6. Hong-Yu Lin
  7. Xuyu Liu
  8. Marcus John Curtis Long  Is a corresponding author
  9. Yimon Aye  Is a corresponding author
  1. École Polytechnique Fédérale de Lausanne, Switzerland
  2. Brigham and Women's Hospital, United States
  3. University of Utah, United States
  4. Xiamen University, China
  5. University of Sydney, Australia
  6. University of Lausanne, Switzerland

Abstract

Studying electrophile signaling is marred by difficulties in parsing changes in pathway flux attributable to on-target, vis-à-vis off-target, modifications. By combining bolus dosing, knockdown, and Z-REX-a tool investigating on-target/on-pathway electrophile signaling, we document that electrophile labeling of one zebrafish-Keap1-paralog (zKeap1b) stimulates Nrf2- driven antioxidant response (AR) signaling (like the human-ortholog). Conversely, zKeap1a is a dominant-negative regulator of electrophile-promoted Nrf2-signaling, and itself is nonpermissive for electrophile-induced Nrf2-upregulation. This behavior is recapitulated in human cells, wherein following electrophile treatment: (1) zKeap1b-transfected cells are permissive for augmented AR-signaling through reduced zKeap1b-Nrf2 binding; (2) zKeap1a-transfected cells are non-permissive for AR-upregulation, as zKeap1a-Nrf2 binding capacity remains unaltered; (3) 1:1 ZKeap1a:zKeap1b-transfected cells show no Nrf2-release from the Keap1-complex, rendering these cells unable to upregulate AR. We identified a zKeap1a-specific point-mutation (C273I) responsible for zKeap1a's behavior. Human-Keap1(C273I), of known diminished Nrf2-regulatory capacity, dominantly muted electrophile-induced Nrf2-signaling. These studies highlight divergent and interdependent electrophile signaling behaviors, despite conserved electrophile sensing.

Data availability

The data generated in this study using these materials are provided in Main Figure 1-8, accompanied by 17 associated Figure Supplements, and the Source Data Files associated with Main Figure 1-8 and 17 associated Figure Supplements.

Article and author information

Author details

  1. Alexandra Van Hall-Beauvais

    École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2515-5191
  2. Jesse R Poganik

    Department of Medicine, Brigham and Women's Hospital, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Kuan-Ting Huang

    École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Saba Parvez

    Department of Pharmacology and Toxicology, University of Utah, Salt lake City, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Yi Zhao

    École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6049-1943
  6. Hong-Yu Lin

    Department of Chemical Biology, Xiamen University, Xiamen, China
    Competing interests
    The authors declare that no competing interests exist.
  7. Xuyu Liu

    School of Chemistry, University of Sydney, New South Wales, Australia
    Competing interests
    The authors declare that no competing interests exist.
  8. Marcus John Curtis Long

    Department of Biochemistry, University of Lausanne, Epalinges, Switzerland
    For correspondence
    marcusjohncurtis.long@unil.ch
    Competing interests
    The authors declare that no competing interests exist.
  9. Yimon Aye

    École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    For correspondence
    yimon.aye@epfl.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1256-4159

Funding

Novartis FreeNovation

  • Yimon Aye

European Research Council

  • Yimon Aye

Swiss Federal Institute of Technology Lausanne

  • Yimon Aye

National Institutes of Health (NIH T32GM008500)

  • Jesse R Poganik

AHA predoctoral Fellowship (17PRE33670395)

  • Jesse R Poganik

HHMI International Fellow

  • Saba Parvez

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

Ethics

Animal experimentation: All procedures performed at Cornell (2017-2018) and EPFL (2018-present) conform to the animal care, maintenance, and experimentation procedures followed by Cornell University's and EPFL's Institutional Animal Care and Use Committee (IACUC) guidelines and approved by the respective institutional committees. All experiments with zebrafish performed at EPFL (2018-present) have been performed in accordance with the Swiss regulations on Animal Experimentation (Animal Welfare Act SR 455 and Animal Welfare Ordinance SR 455.1), in the EPFL zebrafish unit, cantonal veterinary authorization VD-H23).

Reviewing Editor

  1. Jonathan A Cooper, Fred Hutchinson Cancer Research Center, United States

Publication history

  1. Received: September 9, 2022
  2. Preprint posted: October 12, 2022 (view preprint)
  3. Accepted: October 12, 2022
  4. Accepted Manuscript published: October 27, 2022 (version 1)
  5. Accepted Manuscript updated: October 31, 2022 (version 2)
  6. Version of Record published: December 15, 2022 (version 3)
  7. Version of Record updated: June 1, 2023 (version 4)

Copyright

© 2022, Van Hall-Beauvais 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. Alexandra Van Hall-Beauvais
  2. Jesse R Poganik
  3. Kuan-Ting Huang
  4. Saba Parvez
  5. Yi Zhao
  6. Hong-Yu Lin
  7. Xuyu Liu
  8. Marcus John Curtis Long
  9. Yimon Aye
(2022)
Z-REX uncovers a bifurcation in function of Keap1 paralogs
eLife 11:e83373.
https://doi.org/10.7554/eLife.83373

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