FIGURE 3.

Plasma membrane depolarization in response to various stimuli. Mesophyll cells of WT plants (Col-0, A), the pepr1 mutant (B), or the pepr1/pepr2 double mutant (C) were impaled with a microelectrode, and the electrical potential difference across the plasma membrane was registered continuously after addition of various stimuli (10 nm) as indicated in the figure. All peptides elicited transient membrane potential depolarizations with flg22 showing the highest amplitude. Traces are representative measurements of individual experiments (number of repetitions are indicated in Tables 1 and 2). Dose-response curves (D) of the membrane depolarization in response to AtPep1 were obtained from mesophyll cells of WT plants (Col-0, ●), the pepr1 single mutant (○), and the pepr1/pepr2 double mutant (■). The peak depolarization was determined and expressed as a percentage of the maximal depolarization observed in Col-0 with 100 nm AtPep1. Error bars represent S.D. of 6–13 independent assays per data point.