Unbiased proteomic and forward genetic screens reveal that mechanosensitive ion channel MSL10 functions at ER-plasma membrane contact sites in Arabidopsis thaliana

  1. Jennette M Codjoe
  2. Ryan A Richardson
  3. Fionn McLoughlin
  4. Richard David Vierstra
  5. Elizabeth S Haswell  Is a corresponding author
  1. Washington University in St. Louis, United States
  2. SomaLogic, United States

Abstract

Mechanosensitive (MS) ion channels are an evolutionarily conserved way for cells to sense mechanical forces and transduce them into ionic signals. The channel properties of Arabidopsis thaliana MscS-Like (MSL)10 have been well studied, but how MSL10 signals remains largely unknown. To uncover signaling partners of MSL10, we employed both a proteomic screen and a forward genetic screen; both unexpectedly implicated ER-plasma membrane contact sites (EPCSs) in MSL10 function. The proteomic screen revealed that MSL10 associates with multiple proteins associated with EPCSs. Of these, only VAMP-associated proteins (VAP)27-1 and VAP27-3 interacted directly with MSL10. The forward genetic screen, for suppressors of a gain-of-function MSL10 allele (msl10-3G, MSL10S640L), identified mutations in the synaptotagmin (SYT)5 and SYT7 genes. We also found that EPCSs were expanded in leaves of msl10-3G plants compared to the wild type. Taken together, these results indicate that MSL10 associates with and functions with EPCS proteins, providing a new cell-level framework for understanding MSL10 signaling. In addition, placing a mechanosensory protein at EPCSs provides new insight into the function and regulation of this type of subcellular compartment.

Data availability

Mass spectrometry data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD018747, and is included as a Source Data file for Figure 1.

The following data sets were generated

Article and author information

Author details

  1. Jennette M Codjoe

    Department of Biology, Washington University in St. Louis, Saint Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ryan A Richardson

    Department of Biology, Washington University in St. Louis, Saint Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Fionn McLoughlin

    SomaLogic, Boulder, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Richard David Vierstra

    Department of Biology, Washington University in St. Louis, Saint Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0210-3516
  5. Elizabeth S Haswell

    Department of Biology, Washington University in St. Louis, Saint Louis, United States
    For correspondence
    ehaswell@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4246-065X

Funding

HHMI-Simons Faculty Scholar Grant (55108530)

  • Elizabeth S Haswell

National Science Foundation (MCB 1253103)

  • Elizabeth S Haswell

National Science Foundation (CMMI-1548571)

  • Elizabeth S Haswell

National Science Foundation (DGE-1745038)

  • Jennette M Codjoe

William H. Danforth Plant Sciences Fellowship

  • Jennette M Codjoe

National Institutes of Health (R01-GM124452)

  • Richard David Vierstra

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

Reviewing Editor

  1. Yoselin Benitez-Alfonso, University of Leeds, United Kingdom

Publication history

  1. Preprint posted: May 23, 2022 (view preprint)
  2. Received: May 23, 2022
  3. Accepted: October 6, 2022
  4. Accepted Manuscript published: October 7, 2022 (version 1)
  5. Version of Record published: November 1, 2022 (version 2)

Copyright

© 2022, Codjoe 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. Jennette M Codjoe
  2. Ryan A Richardson
  3. Fionn McLoughlin
  4. Richard David Vierstra
  5. Elizabeth S Haswell
(2022)
Unbiased proteomic and forward genetic screens reveal that mechanosensitive ion channel MSL10 functions at ER-plasma membrane contact sites in Arabidopsis thaliana
eLife 11:e80501.
https://doi.org/10.7554/eLife.80501

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