Unconventional secretion of α-synuclein mediated by palmitoylated DNAJC5 oligomers

  1. Shenjie Wu
  2. Nancy C Hernandez Villegas
  3. Daniel W Sirkis
  4. Iona Thomas-Wright
  5. Richard Wade-Martins
  6. Randy Schekman  Is a corresponding author
  1. Howard Hughes Medical Institute, University of California, Berkeley, United States
  2. University of California, Berkeley, United States
  3. University of California, San Francisco, United States
  4. University of Oxford, United Kingdom

Abstract

Alpha-synuclein (α-syn), a major component of Lewy bodies found in Parkinson's disease (PD) patients, has been found exported outside of cells and may mediate its toxicity via cell-to-cell transmission. Here, we reconstituted soluble, monomeric a-syn secretion by the expression of DnaJ homolog subfamily C member 5 (DNAJC5) in HEK293T cells. DNAJC5 undergoes palmitoylation and anchors on the membrane. Palmitoylation is essential for DNAJC5-induced α-syn secretion, and the secretion is not limited by substrate size or unfolding. Cytosolic α-syn is actively translocated and sequestered in an endosomal membrane compartment in a DNAJC5-dependent manner. Reduction of α-syn secretion caused by a palmitoylation-deficient mutation in DNAJC5 can be reversed by a membrane-targeting peptide fusion-induced oligomerization of DNAJC5. The secretion of endogenous α-syn mediated by DNAJC5 is also found in a human neuroblastoma cell line, SH-SY5Y, differentiated into neurons in the presence of retinoic acid, and in human induced pluripotent stem cell-derived midbrain dopamine neurons. We propose that DNAJC5 forms a palmitoylated oligomer to accommodate and export α-syn.

Data availability

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

Article and author information

Author details

  1. Shenjie Wu

    Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7547-0048
  2. Nancy C Hernandez Villegas

    Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3982-7553
  3. Daniel W Sirkis

    Department of Neurology, University of California, San Francisco, San Francisco, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3440-8859
  4. Iona Thomas-Wright

    Department of Physiology, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  5. Richard Wade-Martins

    Department of Physiology, University of Oxford, Oxford, United Kingdom
    Competing interests
    No competing interests declared.
  6. Randy Schekman

    Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    For correspondence
    schekman@berkeley.edu
    Competing interests
    Randy Schekman, Reviewing editor, eLife and Founding Editor-in-Chief, eLife..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8615-6409

Funding

Howard Hughes Medical Institute

  • Randy Schekman

NIH Biology and Biotechnology of Cell and Gene Therapy Training Program (NIH training program T32GM139780)

  • Nancy C Hernandez Villegas

Aligning Science Across Parkinson's (ASAP-020370)

  • Richard Wade-Martins
  • Randy Schekman

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

Copyright

© 2023, Wu 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. Shenjie Wu
  2. Nancy C Hernandez Villegas
  3. Daniel W Sirkis
  4. Iona Thomas-Wright
  5. Richard Wade-Martins
  6. Randy Schekman
(2023)
Unconventional secretion of α-synuclein mediated by palmitoylated DNAJC5 oligomers
eLife 12:e85837.
https://doi.org/10.7554/eLife.85837

Share this article

https://doi.org/10.7554/eLife.85837

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