Figure 9.

Auxin Accumulation Responds to Internal Fe Levels of the Root.

Expression of the auxin-sensitive reporter DR5-GFP in lateral roots of wild-type (Col-0) and irt1 plants in response to localized supply of 50 μM Fe and the concomitant shoot supplementation of 100 μM citrate or Fe-citrate. Seven-day-old seedlings germinated on Fe-deficient medium were transferred to segmented agar plates containing 50 μM Fe-EDTA in the middle segment. Lateral roots were analyzed by confocal laser scanning microscopy after 7 d of treatments (n > 10 seedlings). The experiments were repeated twice, and representative lateral roots are shown. Bars = 100 μm.

[See online article for color version of this figure.]