The RiceYABBY1Gene Is Involved in the Feedback Regulation of Gibberellin Metabolism

• DOI: 10.1104/pp.107.096586
• Publication Date: 2007-03-17T01:25:23Z
• Authors: Mingqiu Dai; Yu Zhao; Qian Ma; Yongfeng Hu; Peter Hedden; Qifa Zhang; Dao-Xiu Zhou
• Keywords: Genetically modified rice

Gibberellin (GA) biosynthesis is regulated by feedback control providing a mechanism for GA homeostasis in plants. However, regulatory elements involved the are not known. In this report, we show that rice (Oryza sativa) YABBY1 (YAB1) gene had similar expression pattern as key biosynthetic genes GA3ox2 and GA20ox2. Overexpression of YAB1 transgenic resulted semidwarf phenotype could be fully rescued applied GA. Quantification endogenous content revealed increases GA(20) decreases GA(1) levels overexpression plants, which transcripts were decreased. Cosuppression plants induced GA3ox2. The repression obtained upon treatment dexamethasone expressing YAB1-glucocorticoid receptor fusion. Importantly, bound to GA-responsive element within promoter. addition, was deregulated signaling mutants either transiently or repressed inhibitor. Finally, cosuppression impaired GA-mediated These data together suggest regulation rice.