Polyploidy underlies co-option and diversification of biosynthetic triterpene pathways in the apple tribe
Wenbing Su, Yi Jing, Shoukai Lin, Zhen Yue, Xianghui Yang, Jiabao Xu, Jincheng Wu, Zhike Zhang, Rui Xia, Jiaojiao Zhu, Ning An, Haixin Chen, Yanping Hong, Yuan Yuan, Ting Long, Ling Zhang, Yuanyuan Jiang, Zongli Liu, Hailan Zhang, Yongshun Gao, Yuexue Liu, Hailan Lin, Huicong Wang, Levi Yant, Shunquan Lin, Zhenhua Liu
Abstract
Significance Plants are a primary source of both traditional and modern drugs due to their astounding capability to synthesize diverse molecules. The fruit tree loquat in the apple tribe has been long used in medicine to treat cough, chronic bronchitis, and asthma, yet why loquat—but not its relatives—evolved these medicinal properties is unknown. Here, we generate high-quality genomes of loquat and a relative, which are separated by a recent whole-genome duplication (WGD) around 13.5 to 27.1 Mya. We revealed the post-WGD diversification of triterpene biosynthesis and the exceptionally high levels of bioactive ursane-type triterpenes specifically in loquat. Our work underscores the importance of WGD-associated metabolic diversification underlying the bioactivity of some medicinal plants.