The Maize ZmBES1/BZR1-9 Transcription Factor Accelerates Flowering in Transgenic and Rice.

In model plants, the BRI1-EMS suppressor 1 (BES1)/brassinazole-resistant 1 (BZR1) transcription factors play vital roles in regulating growth, development, and stimuli response. However, the roles of maize members are largely unknown. In this research, the gene was ectopically expressed in and rice for the phenotyping of flowering. We found that the complementation and overexpression of in mutant and wild type both resulted in early flowering that was about 10 days shorter than in the untransformed control under long-day conditions. In addition, there was no difference in the rosette leaf number between all transgenic lines and the control. Subsequently, the gene was overexpressed in rice. It was found that overexpression lines of rice exhibited early flowering with heading dates that were 8 days shorter compared with untransformed plants. Moreover, the results of RNA-seq and qRT-PCR showed that five flowering-regulated genes, namely , , , , and were significantly up-regulated in all complementary and overexpressing lines of . Meanwhile, the results of RNA-seq showed that 69 and 33 differentially expressed genes (DEGs) were up- and down-regulated in transgenic rice, respectively. Four flowering-related genes, namely , , , and were significantly up-regulated in transgenic lines. To sum up, our findings demonstrate that is involved in controlling flowering and provide insights into further underlying roles of in regulating growth and development in crops.