Department of Biochemistry, Michigan State University, East Lansing, MI, USA.
Department of Plant Biology, Michigan State University, East Lansing, MI, USA.
Nat Commun. 2023 Jan 20;14(1):343. doi: 10.1038/s41467-023-35845-1.
The spatial organization of genes within plant genomes can drive evolution of specialized metabolic pathways. Terpenoids are important specialized metabolites in plants with diverse adaptive functions that enable environmental interactions. Here, we report the genome assemblies of Prunella vulgaris, Plectranthus barbatus, and Leonotis leonurus. We investigate the origin and subsequent evolution of a diterpenoid biosynthetic gene cluster (BGC) together with other seven species within the Lamiaceae (mint) family. Based on core genes found in the BGCs of all species examined across the Lamiaceae, we predict a simplified version of this cluster evolved in an early Lamiaceae ancestor. The current composition of the extant BGCs highlights the dynamic nature of its evolution. We elucidate the terpene backbones generated by the Callicarpa americana BGC enzymes, including miltiradiene and the terpene (+)-kaurene, and show oxidization activities of BGC cytochrome P450s. Our work reveals the fluid nature of BGC assembly and the importance of genome structure in contributing to the origin of metabolites.
植物基因组中基因的空间组织可以驱动专门代谢途径的进化。萜类化合物是植物中重要的专门代谢物，具有多种适应性功能，能够进行环境相互作用。在这里，我们报告了夏枯草、薄荷和假荆芥的基因组组装。我们研究了二萜生物合成基因簇（BGC）的起源及其在唇形科（薄荷科）的其他七个物种中的后续进化。基于在唇形科所有被研究物种的 BGC 中发现的核心基因，我们预测这个簇在一个早期的唇形科祖先中经历了简化。现存 BGC 的组成突出了其进化的动态性质。我们阐明了由美洲夏枯草 BGC 酶产生的萜烯骨干，包括千里光二烯和萜烯（+）-贝壳杉烯，并展示了 BGC 细胞色素 P450 的氧化活性。我们的工作揭示了 BGC 组装的流动性以及基因组结构在代谢物起源中的重要性。
