Figure 1.

Effect of white light on PAO enzyme activity and protein levels in the outer tissues of the maize mesocotyl. Etiolated plants (108 h after soaking in the dark) were irradiated under white light (18,000 lux) for 10 min and extractable PAO activity and protein levels determined in the outer tissues of the mature zone of the maize mesocotyl at the times indicated. A, PAO activity levels (mean values ± sd; n = 3) expressed on a fresh weight basis in dark-grown and light-irradiated plants (inset: PAO activity levels plotted on a lower scale graph). P values have been calculated comparing PAO activity levels in control and irradiated plants for each time. ns, Not significant; *, * *, and * * *, P values ≤ 0.05, 0.01, and 0.001, respectively (the nos. above the bars represent actual P values). B and C, Western immunoblotting carried out after SDS-PAGE loaded on the basis of the equal enzyme activity (B) or total protein content (C).