Nucleophile sensitivity of Drosophila TRPA1 underlies light-induced feeding deterrence
- Sungkyunkwan University School of Medicine, Republic of Korea
- Sungkyunkwan University, Republic of Korea
- Sejong University, Republic of Korea
Abstract
Solar irradiation including ultraviolet (UV) light causes tissue damage by generating reactive free radicals that can be electrophilic or nucleophilic due to unpaired electrons. Little is known about how free radicals induced by natural sunlight are rapidly detected and avoided by animals. We discover that Drosophila Transient Receptor Potential Ankyrin 1 (TRPA1), previously known only as an electrophile receptor, sensitively detects photochemically active sunlight through nucleophile sensitivity. Rapid light-dependent feeding deterrence in Drosophila was mediated only by the TRPA1(A) isoform, despite the TRPA1(A) and TRPA1(B) isoforms having similar electrophile sensitivities. Such isoform dependentce re-emerges in the detection of structurally varied nucleophilic compounds and nucleophilicity-accompanying hydrogen peroxide (H2O2). Furthermore, these isoform-dependent mechanisms require a common set of TRPA1(A)-specific residues dispensable for electrophile detection. Collectively, TRPA1(A) rapidly responds to natural sunlight intensities through its nucleophile sensitivity as a receptor of photochemically generated radicals, leading to an acute light-induced behavioral shift in Drosophila.
Article and author information
Author details
Funding
Ministry of Education (NRF-2015R1D1A1A01057288)
- KyeongJin Kang
Ministry of Education (2015H-1A2A-1034723)
- Tae Jung Ahn
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Leslie C Griffith, Brandeis University, United States
Version history
- Received: June 2, 2016
- Accepted: September 21, 2016
- Accepted Manuscript published: September 22, 2016 (version 1)
- Version of Record published: October 18, 2016 (version 2)
Copyright
© 2016, Du 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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Nucleophile sensitivity of Drosophila TRPA1 underlies light-induced feeding deterrence
eLife 5:e18425.
https://doi.org/10.7554/eLife.18425
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