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Putative interaction site for membrane phospholipids controls activation of TRPA1 channel at physiological membrane potentials
Author(s) -
Macikova Lucie,
Sinica Viktor,
Kadkova Anna,
Villette Sandrine,
Ciaccafava Alexandre,
Faherty Jonathan,
Lecomte Sophie,
Alves Isabel D.,
Vlachova Viktorie
Publication year - 2019
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/febs.14931
Subject(s) - ankyrin , transient receptor potential channel , allosteric regulation , chemistry , biophysics , membrane , lipid bilayer , phosphatidylinositol , biochemistry , peptide , microbiology and biotechnology , cell membrane , ion channel , signal transduction , receptor , biology , gene
The transient receptor potential ankyrin 1 (TRPA1) channel is a polymodal sensor of environmental irritant compounds, endogenous proalgesic agents, and cold. Upon activation, TRPA1 channels increase cellular calcium levels via direct permeation and trigger signaling pathways that hydrolyze phosphatidylinositol‐4,5‐bisphosphate (PIP 2 ) in the inner membrane leaflet. Our objective was to determine the extent to which a putative PIP 2 ‐interaction site (Y1006‐Q1031) is involved in TRPA1 regulation. The interactions of two specific peptides (L992‐N1008 and T1003‐P1034) with model lipid membranes were characterized by biophysical approaches to obtain information about affinity, peptide secondary structure, and peptide effect in the lipid organization. The results indicate that the two peptides interact with lipid membranes only if PIP 2 is present and their affinities depend on the presence of calcium. Using whole‐cell electrophysiology, we demonstrate that mutation at F1020 produced channels with faster activation kinetics and with a rightward shifted voltage‐dependent activation curve by altering the allosteric constant that couples voltage sensing to pore opening. We assert that the presence of PIP 2 is essential for the interaction of the two peptide sequences with the lipid membrane. The putative phosphoinositide‐interacting domain comprising the highly conserved F1020 contributes to the stabilization of the TRPA1 channel gate.