Figure 5.

K⁺_in Channel Current and Extracellular K⁺-Dependent Stomatal Opening Are Reduced in era1-2.

(A) Representative K⁺_in currents in a wild-type guard cell protoplast.

(B) Representative K⁺_in currents in an era1-2 guard cell protoplast.

(C) Current-voltage relationships for K⁺_in currents recorded from wild-type (closed symbols; n = 13) or era1-2 (open symbols; n = 13) guard cell protoplasts.

(D) Stomatal apertures measured after a 2.5-h opening period in the light in the wild type and era1-2. Apertures were measured in 5 mM KCl and 50 μM CaCl₂, pH 6.15, opening buffer (left bars) or in 50 mM KCl and 50 μM CaCl₂, pH 6.15, opening buffer (right bars). Data are means ± sem relative to n = 3 replicates comprising 120 stomates per bar. mCol, Columbia.