Dataset Information

Genetic and proteomic screens suggest that signaling by the mechanosensitive ion channel MSL10 is influenced by its association with a synaptotagmin complex

ABSTRACT: Plants respond to mechanical stressors in a variety of ways, producing electrical and biochemical signals, altering gene expression profiles, and changing organellar organization and morphology. We used a combination of genetic and proteomic approaches to identify genes that modify signaling of MSL10, a mechanosensitive ion channel in Arabidopsis which promotes programmed cell death in response to the mechanical stress from osmotic cell swelling. Mass spectrometry was used to identify proteins that co-immunoprecipitate with MSL10-GFP or with MSL107xD-GFP, a phosphomimetic variant that cannot activate cell death signaling. Interestingly, proteomics identified many proteins that are found at ER-plasma membrane contact sites (EPCSs). Two of the most abundant proteins that co-precipitated with MSL10 are the EPCS proteins VAP27-1 and SYT1, both of which have been reported to relocalize into spherical membrane structures in response to mechanical stress, a phenomenon also observed with MSL10. SYT1 has previously been shown to promote resistance to mechanical stress. A suppressor screen of the gain-of-function msl10-3G allele yielded mutants with point mutations in synaptotagmin (SYT)5 and SYT7, proteins that form a functional complex with SYT1. Together, these results suggest that MSL10 interacts with SYT1, SYT5, and SYT7 at EPCSs and that its cell death signaling output is modulated by this interaction.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Plant Cell, Seedling

SUBMITTER: Fionn McLoughlin

LAB HEAD: Elizabeth Haswell

PROVIDER: PXD018747 | Pride | 2022-10-26

REPOSITORIES: pride

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

Codjoe Jennette M JM Richardson Ryan A RA McLoughlin Fionn F Vierstra Richard David RD Haswell Elizabeth S ES

eLife 20221007

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 <i>Arabidopsis thaliana</i> MscS-Like (MSL)10 have been well studied, but how MSL10 signals remains largely unknown. To uncover signaling partners of MSL10, we employed a proteomic screen and a forward genetic screen; both unexpectedly implicated endoplasmic reticulum-plasma membrane contact sites (EPCSs) in MSL10 function. T ...[more]

PMID: 36205399

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			Action	DRS
	191014MLS10PD.msf	Msf
	191014MLS10PD.pep.xml	Pepxml
	7D_1_1.raw	Raw
	7D_1_2.raw	Raw
	7D_2_1.raw	Raw