Mouse TRPA1 function and membrane localization is modulated by direct interactions with cholesterol
Abstract
The cation channel TRPA1 transduces a myriad of noxious chemical stimuli into nociceptor electrical excitation and neuropeptide release, leading to pain and neurogenic inflammation. Despite emergent evidence that TRPA1 is regulated by the membrane environment, it remains unknown whether this channel localizes in membrane microdomains or whether it interacts with cholesterol. Using total internal reflection fluorescence microscopy and density gradient centrifugation we found that mouse TRPA1 localizes preferably into cholesterol-rich domains and functional experiments revealed that cholesterol depletion decreases channel sensitivity to chemical agonists. Moreover, we identified two structural motifs in transmembrane segments 2 and 4 involved in mTRPA1-cholesterol interactions that are necessary for normal agonist sensitivity and plasma membrane localization. We discuss the impact of such interactions on TRPA1 gating mechanisms, regulation by the lipid environment, and role of this channel in sensory membrane microdomains, all of which helps to understand the puzzling pharmacology and pathophysiology of this channel.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data has been provided for figures 1S1, 2S1, 3, 3S1, 3S3, 5, 7, 8.
Article and author information
Author details
Funding
Research Council KU Leuven (GOA/14/11)
- Karel Talavera
FWO (G070212N)
- Karel Talavera
FWO (Postdoctoral Fellowship)
- Yeranddy A Alpizar
Research Council KU Leuven (C14/18/086)
- Karel Talavera
FWO (G0C7715N)
- Karel Talavera
FWO (G0D0417N)
- Karel Talavera
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All protocols were in accordance with the European Community and Belgian Governmental guidelines for the use and care of experimental animals (2010/63/EU, CE Off Jn8L358, LA12110551) and approved by the KU Leuven Ethical Committee Laboratory Animals (Permit Code: In vitro, Prof. Rudi Vennekens).
Copyright
© 2019, Startek 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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