A chromosome-level Dendrobium moniliforme genome assembly reveals the regulatory mechanisms of flavonoid and carotenoid biosynthesis pathways

作者：Jiapeng Yang, Qiqian Xue, Chao Li, Yingying Jin, Qingyun Xue, Wei Liu, Zhitao Niu, Xiaoyu Ding · 发表于：Acta Pharmaceutica Sinica B · 年份：2025 · DOI：10.1016/j.apsb.2025.03.005 · 被引用次数：8 · 研究领域：Biological and pharmacological studies of plants、Plant Gene Expression Analysis、Plant and animal studies

Dendrobium moniliforme ( D. moniliforme ) is a traditional medicinal herb widely cultivated in Asia. Flavonoids, one of the largest groups of secondary metabolites in plants, are significant medicinal components in Dendrobium species. Several subgroups of R2R3-MYB proteins have been validated to directly regulate flavonoid biosynthesis. Using PacBio sequencing technology, we assembled a high-quality chromosome-level D. moniliforme genome with a total length of 1.20 Gb and a contig N50 of 3.97 Mb. The BUSCO assessment of genome annotation was 91.4%. By integrating the genome and transcriptome, we identified biosynthesis pathway enzyme genes related to flavonoids, polysaccharides, carotenoids, and alkaloids. A total of 90 R2R3-MYBs were identified in D. moniliforme and classified into 21 subgroups. Studies on the functions of R2R3-MYB transcription factors revealed that R2R3-MYB in SG6 can up-regulate flavonoid biosynthesis. Various validation experiments, including subcellular localization, transient overexpression, UPLC–MS/MS, HPLC, yeast one-hybrid, and dual-luciferase assays, demonstrated that DMYB69 directly up-regulates the expression of enzyme genes involved in flavonoid biosynthesis, increasing the content of flavonoids such as anthocyanin, flavone, and flavonol. Additionally, DMYB44 was shown to directly up-regulate the expression of carotenoid biosynthesis enzyme genes, thereby increasing carotenoid content. This study provides an essential genome resource and theoret...