Extended Data Fig. 8: Modulating the levels of ARF transcriptional regulators regulates the expression of associated ARFs.

a–f, Comparison of ARF expression in wild-type versus mutants in roots. g, Comparison of pARF7::VENUS expression in wild-type versus wrky38 shoot. For quantification (see f), fluorescence was measured in the central zone and primordia 2 (green circles). h, Quantification of fluorescence changes shown as relative changes in mean fluorescence level in mutant compared to wild type (single value). Quantifications are shown for a–g and for Fig. 3c,d. In roots, the total pARF7/19-driven fluorescent signal was quantified within a standardized zone covering the stele meristem zone and quantified relative to the wild-type controls. In the shoot, L1 and L2 correspond to quantification in the corresponding layers in the SAM of wild-type and nf-yb13 (see also Fig. 3c, d). Quantification demonstrated a significant change in pattern in wrky38 mutant SAMs (g), with an increase of pARF7 activity in the centre and a loss of the differential expression between the SAM centre and lateral organs. Statistical analysis: unpaired two-sided t-test with P ≤ 0.01 (**). Number of samples observed and quantified: for mutant/wild type roots, 13/13 for crf10, 12/14 for wrky38, 9/9 for nf-yb13, 9/8 for At2g26940, 12/11 for myb65, 12/10 for nlp5; 7 shoots for nf-yb13 and wild-type controls; 7 shoots for wrky38 and 6 wild-type controls. P values from left to right: 0.003, 2e-05, 3e-08, 0.26, 0.57, 0.11, 0.84, 0.007, 0.009. Raw data are provided in Supplementary Table 11. i, Inducible constitutive overexpression of CRF10:mCherry and AL3:mCherry in the pARF7::VENUS line. pARF7::VENUS is shown in yellow and the transcription factors fused to mCherry in red following a 24h induction with β-oestradiol. j, Both lines shown in i show a significant reduction in pARF7::VENUS expression. Unpaired two-sided t-test: P = 4e-10 (CRF10) and 2e-10 (AL3). Number of plants: wild-type control, n = 15; CRF10, n = 21; AL3, n = 20. Error bars: mean ± s.d.. Scale bars: 45 μm for root images; 50 μm for shoot images. For each analysis, the confocal settings were identical in the compared genetic backgrounds. All experiments were done two times.