LGG-1/GABARAP lipidation is not required for autophagy and development in Caenorhabditis elegans

  1. Romane Leboutet
  2. Céline Largeau
  3. Leonie Müller
  4. Magali Prigent
  5. Grégoire Quinet
  6. Manuel S Rodriguez
  7. Marie-Hélène Cuif
  8. Thorsten Hoppe
  9. Emmanuel Culetto
  10. Christophe Lefebvre
  11. Renaud Legouis  Is a corresponding author
  1. Université Paris-Saclay, CEA, CNRS, France
  2. University of Cologne, Germany
  3. Laboratoire de Chimie de Coordination (LCC), CNRS, France

Abstract

The ubiquitin-like proteins Atg8/LC3/GABARAP are required for multiple steps of autophagy, such as initiation, cargo recognition and engulfment, vesicle closure and degradation. Most of LC3/GABARAP functions are considered dependent on their post-translational modifications and their association with the autophagosome membrane through a conjugation to a lipid, the phosphatidyl-ethanolamine. Contrarily to mammals, C. elegans possesses single homologs of LC3 and GABARAP families, named LGG-2 and LGG-1. Using site-directed mutagenesis, we inhibited the conjugation of LGG-1 to the autophagosome membrane and generated mutants that express only cytosolic forms, either the precursor or the cleaved protein. LGG-1 is an essential gene for autophagy and development in C. elegans, but we discovered that its functions could be fully achieved independently of its localization to the membrane. This study reveals an essential role for the cleaved form of LGG-1 in autophagy but also in an autophagy-independent embryonic function. Our data question the use of lipidated GABARAP/LC3 as the main marker of autophagic flux and highlight the high plasticity of autophagy.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file. Further information and requests for resources and reagents should be directed to the corresponding author, Renaud Legouis (renaud.legouis@i2bc.paris-saclay.fr).

Article and author information

Author details

  1. Romane Leboutet

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  2. Céline Largeau

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Leonie Müller

    Institute for Genetics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Magali Prigent

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Grégoire Quinet

    Laboratoire de Chimie de Coordination (LCC), CNRS, Toulouse, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Manuel S Rodriguez

    Laboratoire de Chimie de Coordination (LCC), CNRS, Toulouse, France
    Competing interests
    The authors declare that no competing interests exist.
  7. Marie-Hélène Cuif

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  8. Thorsten Hoppe

    Institute for Genetics, University of Cologne, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4734-9352
  9. Emmanuel Culetto

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4725-2654
  10. Christophe Lefebvre

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    Competing interests
    The authors declare that no competing interests exist.
  11. Renaud Legouis

    Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
    For correspondence
    renaud.legouis@i2bc.paris-saclay.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2699-2584

Funding

Fondation pour la Recherche Médicale (ECO20170637554)

  • Romane Leboutet

Agence Nationale de la Recherche (project EAT,ANR-12-BSV2-018)

  • Renaud Legouis

Fondation ARC pour la Recherche sur le Cancer (SFI20111203826)

  • Renaud Legouis

Ligue Contre le Cancer (M29506)

  • Renaud Legouis

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

Copyright

© 2023, Leboutet 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. Romane Leboutet
  2. Céline Largeau
  3. Leonie Müller
  4. Magali Prigent
  5. Grégoire Quinet
  6. Manuel S Rodriguez
  7. Marie-Hélène Cuif
  8. Thorsten Hoppe
  9. Emmanuel Culetto
  10. Christophe Lefebvre
  11. Renaud Legouis
(2023)
LGG-1/GABARAP lipidation is not required for autophagy and development in Caenorhabditis elegans
eLife 12:e85748.
https://doi.org/10.7554/eLife.85748

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https://doi.org/10.7554/eLife.85748

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