SHY2-dose dependent transcriptome analysis

To identify genes involved in auxin respone depending on SHY2 level, we profiled the transcriptome of plants induced differential level of SHY2 by 0.1 nM or 1 μM dexamethosone treatment. For this we used the roots of seedlings expressing non-degradable version of the Aux/IAA3 (shy2-1) fused to the glucocorticoid receptor domain (shy2-1:GR) under the root hair cell specific EXPA7 promoter. The nuclear translocation of the non-degradable Aux/IAA, specifically in root hair cells, that acts as a biomodal switch in regulation of target genes transcription both positively and negatively. Cold treated seeds of the pE7:shy2-1:GR lines were germinated on 0.5 X MS medium with hygromycin (30 μg/ml) and transferred 2.5 d after germination under 16 h light / 8 h dark conditions to plates containing 0.1 nM DEX or 1 μM DEX for 24h. The plates containing EtOH were used for control experiments.