Molecular regulation of oil gland development and biosynthesis of essential oils in <i>Citrus</i> spp.
H T Wang, Jie Ren, Shiyun Zhou, Yao‐Yuan Duan, Chenqiao Zhu, Chuanwu Chen, Ziyan Liu, Qingyou Zheng, Xiang Shu, Zongzhou Xie, X Y Wang, Lijun Chai, Junli Ye, Qiang Xu, Wen‐Wu Guo, Xiuxin Deng, Fei Zhang
Abstract
Secretory structures in terrestrial plants serve as reservoirs for a variety of secondary metabolites. Among these, the secretory cavity of the Rutaceae family is notable for containing essential oils with a wide range of applications. However, the molecular basis underlying secretory cavity development is unknown. Here, we reveal a molecular framework for Citrus oil gland formation. Using genetic mapping and genome editing, we demonstrated that this process requires LATE MERISTEM IDENTITY1 (LMI1), a key regulator of leaf serration. A conserved GCC box element of the LMI1 promoter recruits DORNROSCHEN-like (DRNL) for transcriptional activation. This DRNL-LMI1 cascade triggers MYC5 activation, facilitating the development of oil glands and the biosynthesis of essential oils. Our findings spotlight cis -regulatory divergence within leaf shape genes, propelling novel functional tissue formation.