Nucleophile sensitivity of Drosophila TRPA1 underlies light-induced feeding deterrence

• Published in: eLife Vol. 5
• Main Authors: Du, Eun Jo, Ahn, Tae Jung, Wen, Xianlan, Seo, Dae-Won, Na, Duk L, Kwon, Jae Young, Choi, Myunghwan, Kim, Hyung-Wook, Cho, Hana, Kang, KyeongJin
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 22.09.2016; eLife Sciences Publications, Ltd
• Subjects: Animals; Ankyrins; chemical nociception; Chemicals; Drosophila; Drosophila - physiology; Drosophila - radiation effects; Drosophila Proteins - metabolism; Feeding; Feeding Behavior - radiation effects; feeding deterrence; Free radicals; Free Radicals - metabolism; Hydrogen peroxide; Insects; Isoforms; Light; Mammals; Neuroscience; Neurosciences; nucleophiles; photochemistry; Students; Sunlight; Transient receptor potential proteins; TRPA1; TRPA1 Cation Channel; TRPC Cation Channels - metabolism; Ultraviolet radiation; Xenopus; free radicals; TRPA1; photochemistry; neuroscience; nucleophiles; photobiology; chemical nociception; D. melanogaster; feeding deterrence
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.18425

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 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 was mediated only by the TRPA1(A) isoform, despite the TRPA1(A) and TRPA1(B) isoforms having similar electrophile sensitivities. Such isoform dependence re-emerges in the detection of structurally varied nucleophilic compounds and nucleophilicity-accompanying hydrogen peroxide (H O ). 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 .