Fig. 6.

cpk5/6/11/23 and ost1-3 mutant plants impair 1 mM malate activation of S-type anion channel currents in Arabidopsis thaliana guard cells. (a) Typical whole-cell recording of S-type anion channel currents in guard cell protoplasts of wild type (WT), cpk5/6/11/23 and ost1-3 mutant plants. (b) Steady state current-voltage relationships recorded as in (a). The number of guard cells was n = 4–7. Data are mean ± SE. The pipette solution contained 2 μM free Ca²⁺ (P < 0.01 for cpk5/6/11/23+1 mM malate vs WT+1 mM malate; P < 0.01for ost1-3+1 mM malate vs WT+1 mM malate at −145 mV).