Plant, animal, and human cells all use electrical signals to communicate with each other. Human and animal nerve cells use them to activate muscles. But leaves also send electrical signals to other parts of the plant, especially when they are injured, or threatened by insects.

The international team led by Professor Rainer Hedrich, Head of the Chair for Molecular Plant Physiology and Biophysics at the University of Würzburg in Germany, has discovered the sensor which plants use to sense electric fields. They have identified the part of the ion channel which functions as the sensor for electric voltage activating the channel. Professor Hedrick previously discovered the ion channel in plants which is activated by calcium ions and an electric field. In 2005, scientists found the gene underlying the ion channel.

The research team made the plants appear injured, and their findings show that plants with a hyperactive form of the channel are in constant state of alert and are hypersensitive to injury of insect attacks. They are currently investigating interventions in the channel that help the plants heal again.

More details are available at the University of Würzburg website.

Figure: The functional potassium channel TPC1 consists of two identical subunits (left in the picture). Potassium ions (blue spheres) are guided through the canal pore when calcium ions that bind to the channel protein (green spheres) and changes in the electric field (flashes) actuate the voltage sensors (red cylinders). When the channel opens, an electrical signal (red current trace) is triggered and cells of the sample plant Arabidopsis thaliana depicted here exchange information. (Graphic: Dirk Becker).