(a) TPL binds to the promoters of GATA4 and BZS1 in a BR dependent manner. The TPL-DNA binding was determined by ChIP assay using TPLp::TPL-HA transgenic plants. One-week old seedlings grown on the medium containing 2 µM PPZ were treated with mock (M) or 100 nM BL for 4 hr before crosslinking. Error bars indicate the s.d. (n=3) and **: P<0.01 by Student’s t-test.
(b) The BZR1 transcriptional repression of GATA4 and BZS1 are compromised in the tpl;tpr1;tpr4 triple mutant. Total RNA were extracted from etiolated seedlings grown on the medium containing 2 µM PPZ. The relative expression fold changes of GATA4 and BZS1 were determined by qRT-PCR. Error bars indicate the s.d. (n=3).
(c) The tpl;tpr1;tpr4 seedlings are hypersensitive to red light. Seedlings were grown in various intensities of red light for 5 days. Numbers indicate the percentages of average hypocotyl length relative to that of dark-grown seedling. Error bars indicate the s.d. (n=10).