Vacuolar ion channels: Roles in plant nutrition and signalling

Abstract 

Vacuoles play various roles in many physiologically relevant processes in plants. Some of the more prominent are turgor provision, the storage of minerals and nutrients, and cellular signalling. To fulfil these functions a complement of membrane transporters is present at the tonoplast. Prolific patch clamp studies have shown that amongst these, both selective and non-selective ion channels participate in turgor regulation, nutrient storage and signalling. This article reviews the physiological roles, expression patterns and structure function properties of plant vacuolar anion and cation channels that are gated by voltage and ligands.

Abbreviations: cADPR, cyclic ADP-ribose, FV, fast vacuolar channel, IP₃, myo-inositol 1,4,5-triphosphate, LV, lytic vacuole, NSCC, non-selective cation channel, PMF, proton motive force, PSV, protein storage vacuole, SV, slow vacuolar channel, VK, vacuolar K⁺ channel, TMD, transmembrane domain

Keywords: Ion channel, Plant nutrition, Signalling, Tonoplast transport, Vacuole