Calcium-mediated rapid movements defend against herbivorous insects in Mimosa pudica

Animals possess specialized systems, e.g., neuromuscular systems, to sense the environment and then move their bodies quickly in response. Mimosa pudica, the sensitive plant, moves its leaves within seconds in response to external stimuli; e.g., touch or wounding. However, neither the plant-wide signaling network that triggers these rapid movements nor the physiological roles of the movements themselves have been determined. Here by simultaneous recording of cytosolic Ca2+ and electrical signals, we show that rapid changes in Ca2+ coupled with action and variation potentials trigger rapid movements in wounded M. pudica. Furthermore, pharmacological manipulation of cytosolic Ca2+ dynamics and CRISPR-Cas9 genome editing technology revealed that an immotile M. pudica is more vulnerable to attacks by herbivorous insects. Our findings provide evidence that rapid movements based on propagating Ca2+ and electrical signals protect this plant from insect attacks. Mimosa pudica moves its leaves within seconds of being touched or wounded. Here the authors show that such movements are triggered by rapid changes in Ca2+ and action and variation potentials and provide evidence that rapid movements help protect the plant from insect attacks.

Automated summary

Mimosa pudica moves its leaves within seconds of being touched or wounded. Rapid changes in calcium ions and electric signals trigger these movements. The rapid movements help protect the plant from attacks by herbivorous insects.