Expression of <i>cECT2-mCherry</i> driven by the ribosomal protein <i>US7Y</i> promoter can rescue late leaf emergence in <i>ect2-1/ect3-1/ect4-2</i> (<i>te234</i>) seedlings.

(A) Raw percentages of seedlings with first true leaves >0.5 mm at 10 days after germination among primary transformants of te234 or rdr6-12/te234 plants transformed with US7Yp:cECT2-mCherry-OCSt (cDNA) or US7Yp:mCherry-OCSt (control) compared to ECT2p:gECT2-mCherry-ECT2t (gDNA). (B) Expression pattern in 9-day-old seedlings of the indicated genotypes (T2 for US7Yp-driven constructs, and T5 for ECT2p:gECT2-mCherry-ECT2t). Fluorescence and protein abundance is typically higher in plants expressing free mCherry (US7Yp:mCherry-OCSt) than in fusions of mCherry with ECTs (see S8 and S15 Figs). Although the expression pattern of US7Yp:cECT2-mCherry-OCSt is identical to that of ECT2p:gECT2-mCherry-ECT2t, the fluorescence level and protein abundance observed is typically lower among cDNA lines in the te234 background. Scale bars are 1 mm for images of aerial tissues (upper panels), and 0.1 mm for roots (lower panels). (PDF)