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TRP channel activation by reversible covalent modification.

ABSTRACT: Allyl isothiocyanate, the pungent principle of wasabi and other mustard oils, produces pain by activating TRPA1, an excitatory ion channel on sensory nerve endings. Isothiocyanates are membrane-permeable electrophiles that form adducts with thiols and primary amines, suggesting that covalent modification, rather than classical lock-and-key binding, accounts for their agonist properties. Indeed, we show that thiol reactive compounds of diverse structure activate TRPA1 in a manner that relies on covalent modification of cysteine residues within the cytoplasmic N terminus of the channel. These findings suggest an unusual paradigm whereby natural products activate a receptor through direct, reversible, and covalent protein modification.

SUBMITTER: Hinman A

PROVIDER: S-EPMC1748265 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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TRP channel activation by reversible covalent modification.

Hinman Andrew A Chuang Huai-Hu HH Bautista Diana M DM Julius David D

Proceedings of the National Academy of Sciences of the United States of America 20061212 51

Allyl isothiocyanate, the pungent principle of wasabi and other mustard oils, produces pain by activating TRPA1, an excitatory ion channel on sensory nerve endings. Isothiocyanates are membrane-permeable electrophiles that form adducts with thiols and primary amines, suggesting that covalent modification, rather than classical lock-and-key binding, accounts for their agonist properties. Indeed, we show that thiol reactive compounds of diverse structure activate TRPA1 in a manner that relies on c ...[more]

PMID: 17164327

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