Effects of La3+ and Eu3+ on outward potassium channels in Vicia guard cells

Abstract

Effects of La 3+ and Eu 3+ on outward potassium channels (K + out ) in Vicia guard cells have been studied by patch clamping technique. Extracellular La 3+ inhibited K + out currents with a half-inhibition concentration (IC 50 ) of 81 μmol·L −1 . Interestingly, intracellular La 3+ activated K + out currents at a free concentration of 1.13 × 10 −14 mol·L −1 , and inhibited K + out currents at a free concentration of 5.86 × 10 −14 mol·L −1 . Extracellular Eu 3+ also activated K + out currents at concentrations of 10 μmol·L −1 and 50 μmol·L −1 , and inhibited K + out currents at concentrations of more than 1 mmol·L −1 . The effects of La 3+ and Eu 3+ on K + out currents may contribute to regulation of the plant water status, which may be one of the mechanisms of the biological effect of rare earth elements. rare earth elements, stomata, guard cell, outward potassium channel

Geochemical behaviour of rare earths in Vitis vinifera grafted onto different rootstocks and growing on several soils

“…The role played during REE exploitation in agricultural practices carried out in China is justified by the capability of these elements to favour some metabolic processes leading to increases in plant productivity, by modifying, for example, stomatal openings and regulating transpiration and water depletion through plant leaves (Schroeder et al, 2001). Recent studies offer evidence for the ability of Eu 3+ to intervene on the outward K + channels of Vicia guard cells and consequently regulating the cell water contents (Xue and Yang, 2009).…”

Effects of lanthanum on calcium-activated K+ currents and its kinetics in MC3T3 cells

“…The influence of Ln 3+ on channels in non-excitable cells has not been sufficiently investigated. Xue et al [23] showed the effect of La 3+ on outward potassium channels in Vicia guard cells. We previously studied the effects of Yb 3+ on potassium current in non-excitable NIH3T3 cells [24].…”