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A centipede toxin causes rapid desensitization of nociceptor TRPV1 ion channel.

ABSTRACT: The nociceptive transient receptor potential vanilloid 1 (TRPV1) ion channel is a polymodal receptor for multiple painful stimuli, hence actively pursued as a target for analgesic drugs. We identified a small peptide toxin RhTx2 from the Chinese red-headed centipede that strongly modulates TRPV1 activities. RhTx2, a 31-amino-acid peptide, is similar to a TRPV1-activating toxin RhTx we have previously discovered but with four extra amino acids at the N terminus. We observed that, like RhTx, RhTx2 activated TRPV1, but RhTx2 rapidly desensitized the channel upon prolonged exposure. Desensitization was achieved by reducing both the open probability and the single-channel conductance. RhTx2 is not only a tool to study the desensitization mechanism of TRPV1, but also a promising starting molecule for developing novel analgesics.

SUBMITTER: Zhu A

PROVIDER: S-EPMC7388746 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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A centipede toxin causes rapid desensitization of nociceptor TRPV1 ion channel.

Zhu Aiqin A Aierken Aerziguli A Yao Zhihao Z Vu Simon S Tian Yuhua Y Zheng Jie J Yang Shilong S Yang Fan F

Toxicon : official journal of the International Society on Toxinology 20200222

The nociceptive transient receptor potential vanilloid 1 (TRPV1) ion channel is a polymodal receptor for multiple painful stimuli, hence actively pursued as a target for analgesic drugs. We identified a small peptide toxin RhTx2 from the Chinese red-headed centipede that strongly modulates TRPV1 activities. RhTx2, a 31-amino-acid peptide, is similar to a TRPV1-activating toxin RhTx we have previously discovered but with four extra amino acids at the N terminus. We observed that, like RhTx, RhTx2 ...[more]

PMID: 32097697

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