Syntaxin-1A modulates vesicle fusion in mammalian neurons via juxtamembrane domain dependent palmitoylation of its transmembrane domain

  1. Gülçin Vardar  Is a corresponding author
  2. Andrea Salazar-Lázaro
  3. Sina Zobel
  4. Thorsten Trimbuch
  5. Christian Rosenmund  Is a corresponding author
  1. Charité - Universitätsmedizin Berlin, Germany

Abstract

SNAREs are undoubtedly one of the core elements of synaptic transmission. Contrary to the well characterized function of their SNARE domains bringing the plasma and vesicular membranes together, the level of contribution of their juxtamembrane domain (JMD) and the transmembrane domain (TMD) to the vesicle fusion is still under debate. To elucidate this issue, we analyzed three groups of STX1A mutations in cultured mouse hippocampal neurons: 1) elongation of STX1A's JMD by three amino acid insertions in the junction of SNARE-JMD or JMD-TMD; 2) charge reversal mutations in STX1A's JMD; and 3) palmitoylation deficiency mutations in STX1A's TMD. We found that both JMD elongations and charge reversal mutations have position dependent differential effects on Ca2+-evoked and spontaneous neurotransmitter release. Importantly, we show that STX1A's JMD regulates the palmitoylation of STX1A's TMD and loss of STX1A palmitoylation either through charge reversal mutation K260E or by loss of TMD cysteines inhibits spontaneous vesicle fusion. Interestingly, the retinal ribbon specific STX3B has a glutamate in the position corresponding to the K260E mutation in STX1A and mutating it with E259K acts as a molecular on-switch. Furthermore, palmitoylation of post-synaptic STX3A can be induced by the exchange of its JMD with STX1A's JMD together with the incorporation of two cysteines into its TMD. Forced palmitoylation of STX3A dramatically enhances spontaneous vesicle fusion suggesting that STX1A regulates spontaneous release through two distinct mechanisms: one through the C-terminal half of its SNARE domain and the other through the palmitoylation of its TMD.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files that contain numerical data used to generate the figures have been provided for all figures. Source Data that contain the whole Western Blot images are provided Figures 3, 4, 6, and 8.

Article and author information

Author details

  1. Gülçin Vardar

    Department of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    For correspondence
    gulcinv@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
  2. Andrea Salazar-Lázaro

    Department of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Sina Zobel

    Department of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Thorsten Trimbuch

    Department of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Christian Rosenmund

    Department of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
    For correspondence
    christian.rosenmund@charite.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3905-2444

Funding

Deutsche Forschungsgemeinschaft (388271549)

  • Christian Rosenmund

Deutsche Forschungsgemeinschaft (399894546)

  • Christian Rosenmund

Deutsche Forschungsgemeinschaft (436260754)

  • Christian Rosenmund

Deutsche Forschungsgemeinschaft (27800197)

  • Christian Rosenmund

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

Reviewing Editor

  1. Reinhard Jahn, Max Planck Institute for Biophysical Chemistry, Germany

Ethics

Animal experimentation: All procedures for animal maintenance and experiments were in accordance with the regulations of and approved by the animal welfare committee of Charité-Universitätsmedizin and the Berlin state government Agency for Health and Social Services under license number T0220/09.

Version history

  1. Received: February 25, 2022
  2. Preprint posted: March 12, 2022 (view preprint)
  3. Accepted: May 30, 2022
  4. Accepted Manuscript published: May 31, 2022 (version 1)
  5. Version of Record published: June 9, 2022 (version 2)

Copyright

© 2022, Vardar 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.

Metrics

  • 1,422
    views
  • 390
    downloads
  • 13
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Gülçin Vardar
  2. Andrea Salazar-Lázaro
  3. Sina Zobel
  4. Thorsten Trimbuch
  5. Christian Rosenmund
(2022)
Syntaxin-1A modulates vesicle fusion in mammalian neurons via juxtamembrane domain dependent palmitoylation of its transmembrane domain
eLife 11:e78182.
https://doi.org/10.7554/eLife.78182

Share this article

https://doi.org/10.7554/eLife.78182

Further reading

    1. Genetics and Genomics
    2. Neuroscience
    Kenneth Chiou, Noah Snyder-Mackler
    Insight

    Single-cell RNA sequencing reveals the extent to which marmosets carry genetically distinct cells from their siblings.

    1. Neuroscience
    Flavio J Schmidig, Simon Ruch, Katharina Henke
    Research Article

    We are unresponsive during slow-wave sleep but continue monitoring external events for survival. Our brain wakens us when danger is imminent. If events are non-threatening, our brain might store them for later consideration to improve decision-making. To test this hypothesis, we examined whether novel vocabulary consisting of simultaneously played pseudowords and translation words are encoded/stored during sleep, and which neural-electrical events facilitate encoding/storage. An algorithm for brain-state-dependent stimulation selectively targeted word pairs to slow-wave peaks or troughs. Retrieval tests were given 12 and 36 hr later. These tests required decisions regarding the semantic category of previously sleep-played pseudowords. The sleep-played vocabulary influenced awake decision-making 36 hr later, if targeted to troughs. The words’ linguistic processing raised neural complexity. The words’ semantic-associative encoding was supported by increased theta power during the ensuing peak. Fast-spindle power ramped up during a second peak likely aiding consolidation. Hence, new vocabulary played during slow-wave sleep was stored and influenced decision-making days later.