Basic Information:
Series_titleTranscriptional profiling of leaf blades and petioles subjected to shade avoidance syndrome
Series_summaryPlants grown under a canopy recognize changes in light quality and modify their growth patterns; this modification is known as shade avoidance syndrome. In leaves, leaf blade expansion is suppressed, whereas petiole elongation is promoted under the shade. However, the mechanisms that control these responses are largely unclear. Here, we demonstrated that both auxin and brassinosteroid (BR) are required for the normal leaf responses to shade. The microarray analysis of leaf blades and petioles treated with end-of-day far-red light (EODFR) revealed that almost half of the genes induced by the treatment in both parts were previously identified as auxin-responsive genes. Likewise, BR-responsive genes were overrepresented in the EODFR-induced genes. Hence, the auxin and BR responses were elevated by EODFR treatment in both leaf blades and petioles, although opposing growth responses were observed in these two parts. The analysis of the auxin-deficient doc1/big mutant and BR-deficient rot3/cyp90c1 mutant further indicates that auxin and BR were equally required for the normal petiole elongation response to the shade stimulus. In addition, the spotlight irradiation experiment revealed that phytochrome in leaf blades but not that in petioles regulated petiole elongation, which was probably mediated through regulation of the auxin/BR responses in petioles. On the basis of these findings, we conclude that auxin and BR cooperatively promote petiole elongation in response to the shade stimulus under the control of phytochrome in the leaf blade.
Series_overall_designThe WT seedlings were grown for 19 days under continuous white light condition before experimental treatment with three light conditions. Seedlings were either maintained in white light for 2 h (WL), incubated in the dark condition for 2 h (D), or experienced a pulse irradiation of FR light before incubated in the dark condition for 2 h (FRD). Total RNAs were separately prepared from leaf blades and petioles after each light treatment. Three independent biological replicates were used.
Series_typeExpression profiling by array
Series_sample_idGSM445710 GSM445711 GSM445712 GSM445713 GSM445714 GSM445715 GSM445716 GSM445717 GSM445718 GSM445719 GSM445720 GSM445721 GSM445722 GSM445723 GSM445724 GSM445725 GSM445726 GSM445727