Analysis of SUMO1-conjugation at Synapses

  1. James A Daniel
  2. Benjamin H Cooper
  3. Jorma J Palvimo
  4. Fu-ping Zhang
  5. Nils Brose
  6. Marilyn Tirard  Is a corresponding author
  1. Max Planck Institute of Experimental Medicine, Germany
  2. University of Eastern Finland, Finland
  3. University of Turku, Finland

Abstract

SUMO1-conjugation of proteins at neuronal synapses is considered to be a major post-translational regulatory process in nerve cell and synapse function, but the published evidence for SUMO1-conjugation at synapses is contradictory. We employed multiple genetic mouse models for stringently controlled biochemical and immunostaining analyses of synaptic SUMO1-conjugation. By using a knock-in reporter mouse line expressing tagged SUMO1, we could not detect SUMO1-conjugation of seven previously proposed synaptic SUMO1-targets in the brain. Further, immunostaining of cultured neurons from wild-type and SUMO1 knock-out mice showed that anti-SUMO1 immunolabelling at synapses is non-specific. Our findings indicate that SUMO1-conjugation of synaptic proteins does not occur or is extremely rare and hence not detectable using current methodology. Based on our data, we discuss a set of experimental strategies and minimal consensus criteria for the validation of SUMOylation that can be applied to any SUMOylation substrate and SUMO isoform.

Article and author information

Author details

  1. James A Daniel

    Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2781-4544
  2. Benjamin H Cooper

    Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Jorma J Palvimo

    Institute of Biomedicine, University of Eastern Finland, Kuopio, Finland
    Competing interests
    The authors declare that no competing interests exist.
  4. Fu-ping Zhang

    Institute of Biomedicine, University of Turku, Turku, Finland
    Competing interests
    The authors declare that no competing interests exist.
  5. Nils Brose

    Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  6. Marilyn Tirard

    Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
    For correspondence
    tirard@em.mpg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5669-9610

Funding

Max-Planck-Gesellschaft (Open-access funding)

  • Marilyn Tirard

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 animal experiments were performed in accordance with the guidelines for the welfare of experimental animals issued by the State Government of Lower Saxony, Germany, in compliance with European and NIH guidelines (33.9-42502-04-13/1359).

Reviewing Editor

  1. Gary L Westbrook, Vollum Institute, United States

Publication history

  1. Received: February 28, 2017
  2. Accepted: June 7, 2017
  3. Accepted Manuscript published: June 9, 2017 (version 1)
  4. Version of Record published: June 30, 2017 (version 2)

Copyright

© 2017, Daniel 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. James A Daniel
  2. Benjamin H Cooper
  3. Jorma J Palvimo
  4. Fu-ping Zhang
  5. Nils Brose
  6. Marilyn Tirard
(2017)
Analysis of SUMO1-conjugation at Synapses
eLife 6:e26338.
https://doi.org/10.7554/eLife.26338

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