Fast activated outward cation channel activation allows H⁺-ATPase and anion channel reactivation upon strong depolarization in young root hairs ofArabidopsis thaliana

Root hairs are a primary site for nutrient absorption and sensors of the root environment where signaling processes are initiated. Regulation of plasma membrane transports are fundamental for root hair tip growth, plant nutrition and responses to environmental signals. If efforts have been made to undercover the repertoires of root hair ion system transports, the roles of some of these ion transport systems remain elusive. Here we describe, using discontinuous single electrode voltage clamp, a technic that allows working in intact root hairs, the putative role of an outward current presenting a quite chaotic activation, in the polarization regulation of root hairs ofArabidopsis thaliana.