Centipedes subdue giant prey by blocking KCNQ channels.

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.