Fig. 1
The pOp6/LhGR system in rice: a proof of principle. A A schematic representation of the pVecLhGR2 construct that contains the Arabidopsis codon-optimized GAL4 sequence [46] of the transcriptional activator LhGR2 driven by a pZmUbi promoter (containing an intron), a bidirectional pOp6 promotor version with two TMV Ω translation enhancers driving two reporter genes - uidA (encoding β-glucuronidase; GUS) and a yellow fluorescence protein (YFP), and a pCaMV35S::HYG selectable marker cassette conferring hygromycin resistance. TOCS, octopine synthase terminator; T35S, cauliflower mosaic virus 35S terminator; TNOS, nopaline synthase terminator; LB, T-DNA left border; RB, T-DNA right border. The construct was assembled as detailed in Supplementary Fig. S1. B Twelve-day-old rice seedlings of three independent transgenic lines (number 65, 100 and 121) histochemically stained for GUS activity that was induced by seedling transfer onto ½ MS plates containing 30 μM Dex or control DMSO (−Dex) for 6 days. Seedlings of pZmUbi::GUS and non-transgenic (NT) were included as controls. The arrows point to an example of damaged cells/ cuts where the GUS staining substrate (5-bromo-4-chloro-3-indolyl glucuronide; X-Gluc) penetrated inside the cells. Scale bar represents 1 cm. C Leaves of 4-week-old plant (line 121) were painted with 30 μM Dex or control solution (−Dex) and imaged using a confocal laser scanning microscope 96 h later to detect YFP fluorescence. NT was included as a control for autofluorescence. The scale bar is 20 μm