Key Laboratory of Molecular Epigenetics of MOE, Northeast Normal University, Changchun 130024, China.
Flower Research Institute, Yunnan Academy of Agricultural Sciences, Kunming 650205, China.
Plant Physiol. 2024 Nov 4;196(3):1908-1922. doi: 10.1093/plphys/kiae444.
The fascinating scent of rose (Rosa genus) flowers has captivated human senses for centuries, making them one of the most popular and widely used floral fragrances. Despite much progress over the last decade, many biochemical pathways responsible for rose scents remain unclear. We analyzed the floral scent compositions from various rose varieties and selected the modern cultivar Rosa hybrida "Double Delight" as a model system to unravel the formation of rose dominant volatile terpenes, which contribute substantially to the rose fragrance. Key genes involved in rose terpene biosynthesis were functionally characterized. Cytosolic geranyl diphosphate (GPP) generated by geranyl/farnesyl diphosphate synthase (G/FPPS1) catalysis played a pivotal role in rose scent production, and terpene synthases in roses play an important role in the formation of most volatile terpenes, but not for geraniol, citral, or β-citronellol. Subsequently, a series of enzymes, including geraniol dehydrogenase, geranial reductase, 12-oxophytodienoate reductase, and citronellal reductase, were characterized as involved in the transformation of geraniol to β-citronellol in roses through three successive steps. Interestingly, the β-citronellol biosynthesis pathway appears to be conserved in other horticultural plants like Lagerstroemia caudata and Paeonia lactiflora. Our findings provide valuable insights into the biosynthesis of rose volatile terpenoid compounds and offer essential gene resources for future breeding and molecular modification efforts.
玫瑰（Rosa 属）花朵迷人的香气已经吸引了人类数个世纪，使它们成为最受欢迎和广泛使用的花卉香料之一。尽管在过去十年中取得了许多进展，但许多负责玫瑰香气的生化途径仍不清楚。我们分析了各种玫瑰品种的花香成分，并选择现代栽培品种杂交茶香玫瑰“双份喜悦”作为模型系统，以揭示玫瑰主要挥发性萜烯的形成，这些萜烯对玫瑰的香气有很大贡献。参与玫瑰萜烯生物合成的关键基因的功能得到了表征。香叶基二磷酸（GPP）由香叶基/法尼基二磷酸合酶（G/FPPS1）催化生成，在玫瑰香气产生中起着关键作用，玫瑰中的萜烯合酶在形成大多数挥发性萜烯方面起着重要作用，但对香叶醇、柠檬醛或β-香茅醇则不然。随后，一系列酶，包括香叶醇脱氢酶、橙花醛还原酶、12-氧代植物二烯酸还原酶和香茅醛还原酶，被鉴定为参与玫瑰中香叶醇向β-香茅醇的转化，通过三个连续的步骤。有趣的是，β-香茅醇生物合成途径似乎在其他园艺植物中如紫薇和牡丹中是保守的。我们的研究结果为玫瑰挥发性萜烯化合物的生物合成提供了有价值的见解，并为未来的育种和分子修饰工作提供了必要的基因资源。
