The Functional Potassium Channel TPC1 (IMAGE) University of Würzburg Caption 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. Credit Graphic: Dirk Becker Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.