Fig. 2.

Promoter activity of BTSL1 and BTSL2. Promoter sequences of BTSL1 (−880 nt) and BTSL2 (−2097 nt) were inserted upstream of eGFP-GUS and the constructs were stably expressed in wild-type Arabidopsis. (A) GFP fluorescence in seedlings grown on medium with 50 μM FeEDTA (+Fe) or with 100 µM ferrozine to deplete Fe (−Fe) for 6 d. (Scale bar, 1 mm.) (B) GFP fluorescence in optical transverse sections of roots in 6-d-old seedlings grown −Fe. Cell walls were stained with propidium iodide (red). (Scale bar, 50 μm.) (C) GUS activity staining in seedlings grown −Fe for 8 d. Scale bar is 0.5 mm for whole seedlings, 100 μm for a close-up of the root tip, and 50 μm for root cross-sections. Images are representative of 3 independent lines for each promoter construct.