Transcriptional Regulatory Network of GA Floral Induction Pathway in LA Hybrid Lily

Abstract

200mg/L exogenous GA₃ can successfully break the bulb's dormancy of the LA hybrid lily and significantly accelerated the flowering process, indicating that gibberellin floral induction pathway is present in the LA lily 'Aladdin'. With the GCNs analysis, two second messenger G protein-coupled receptor related genes that respond to gibberellin signals in the cell were discovered. The downstream transport proteins such as <i>AMT</i>, <i>calcium transport ATPase</i>, and <i>plasma membrane ATPase</i> were also discovered participating in GA signal transduction. Transcription factors including <i>WRKY7</i>, <i>NAC2</i>, <i>NAC11</i>, and <i>CBF</i> specially regulated phosphorylation and glycosylation during the ubiquitination degradation process of <i>DELLA</i> proteins. These transcription factors also activated in abscisic acid metabolism. A large number of transcription factors such as <i>WRKY21</i>, <i>WRKY22</i>, <i>NAC1</i>, <i>AP2</i>, <i>EREB1</i>, <i>P450</i>, and <i>CYP81</i> that both regulate gibberellin signaling and low-temperature signals have also been found. Finally, the molecular mechanism of GA floral induction pathway in the LA hybrid lily 'Aladdin' was constructed.