Figure 2.

PLDα1 and PA Mediate ABA-Enhanced NADPH Oxidase Activity and ROS Production.

(A) Isolated MCPs and GCPs (top panel); immunoblotting of PLDα1 (bottom panel). Proteins from the wild type (MCPs, 26 μg; GCPs, 15 μg) and pldα1 (MCPs, 30 μg; GCPs, 22 μg) were separated by 8% SDS-PAGE. PLDα1 was made visible by alkaline phosphatase staining after blotting with PLDα antibody.

(B) ABA-induced O₂⁻ production in the wild type and pldα1 GCPs (4 × 10⁴ protoplasts). GCPs were treated with 10 μM (±) ABA dissolved in 0.02% (v/v) ethanol (+ABA) or 0.02% (v/v) ethanol only (−ABA). O₂⁻ production was measured by the detection of XTT formazan using spectrophotometric analysis at A₄₇₀. Data are means ± se of three independent experiments.