Fig. 2: Cation dependency of AtHAK5.

A Box plot of cation-induced peak currents (ΔI_peak) at −120 mV of oocytes co-expressing AtHAK5 and CIPK23/CBL1 in response to either 2 mM Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺ or NH₄⁺ (n = 5 experiments). B Representative current response of AtHAK5/CIPK23/CBL1 co-expressing oocytes upon application of different NH₄⁺ concentrations. C Normalized whole-oocyte NH₄⁺-induced peak currents (ΔI_peak) at −120 mV (pH4.5) plotted against the applied NH₄⁺-concentration. K_m (NH₄⁺) was calculated by fitting ΔI_peak with a Michaelis-Menten equation. (n = 6 experiments, mean ± SD). D Box plot of peak current response (ΔI_peak) of AtHAK5/CIPK23/CBL1 co-expressing oocytes in the presence of either 10 µM K⁺ or different NH₄⁺-concentrations as indicated in the figure (n = 4 experiments for 20, 50, 100 µM NH₄⁺ and n = 5 experiments for 10 µM K⁺ and NH₄⁺, mean ± SD).