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Centipedes subdue giant prey by blocking KCNQ channels.

ABSTRACT: Centipedes can subdue giant prey by using venom, which is metabolically expensive to synthesize and thus used frugally through efficiently disrupting essential physiological systems. Here, we show that a centipede (Scolopendra subspinipes mutilans, ?3 g) can subdue a mouse (?45 g) within 30 seconds. We found that this observation is largely due to a peptide toxin in the venom, SsTx, and further established that SsTx blocks KCNQ potassium channels to exert the lethal toxicity. We also demonstrated that a KCNQ opener, retigabine, neutralizes the toxicity of a centipede's venom. The study indicates that centipedes' venom has evolved to simultaneously disrupt cardiovascular, respiratory, muscular, and nervous systems by targeting the broadly distributed KCNQ channels, thus providing a therapeutic strategy for centipede envenomation.

SUBMITTER: Luo L

PROVIDER: S-EPMC5816164 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Centipedes subdue giant prey by blocking KCNQ channels.

Luo Lei L Li Bowen B Wang Sheng S Wu Fangming F Wang Xiaochen X Liang Ping P Ombati Rose R Chen Junji J Lu Xiancui X Cui Jianmin J Lu Qiumin Q Zhang Longhua L Zhou Ming M Tian Changlin C Yang Shilong S Lai Ren R

Proceedings of the National Academy of Sciences of the United States of America 20180122 7

Centipedes can subdue giant prey by using venom, which is metabolically expensive to synthesize and thus used frugally through efficiently disrupting essential physiological systems. Here, we show that a centipede (<i>Scolopendra subspinipes mutilans</i>, ∼3 g) can subdue a mouse (∼45 g) within 30 seconds. We found that this observation is largely due to a peptide toxin in the venom, SsTx, and further established that SsTx blocks KCNQ potassium channels to exert the lethal toxicity. We also demo ...[more]

PMID: 29358396

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