Demystifying the Venus flytrap action potential.

All plants are electrically excitable, but only few are known to fire a well-defined, all-or-nothing action potential (AP). The Venus flytrap Dionaea muscipula displays APs with an extraordinarily high firing frequency and speed, enabling the capture organ of this carnivorous plant to catch small animals as fast as flies. The number of APs triggered by the prey is counted and serves as the basis for decisions within the flytrap's hunting cycle. The archetypical Dionaea AP lasts 1 s and consists of five phases: Starting from the resting state, an initial cytosolic Ca transient is followed by depolarization, repolarization and a transient hyperpolarization (overshoot) before the original membrane potential is finally recovered. When the flytrap matures and becomes excitable, a distinct set of ion channels, pumps and carriers is expressed, each mastering a distinct AP phase.