title: Flowery odor formation revealed by differential expression of monoterpene biosynthetic genes and monoterpene accumulation in rose (Rosa rugosa Thunb.).
abstract: Rosa rugosa is an important ornamental and economical plant. In this paper, four genes encoding 1-deoxy-D-xylulose-5-phosphate synthase (DXS), 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR), alcohol acyltransferase (AAT) and linalool synthase (LIS) involved in the monoterpene biosynthesis pathways were isolated from R. rugosa 'Tangzi', and the expression patterns of these genes in different flower development stages and different parts of floral organs were determined by real-time quantitative fluorescence PCR. Furthermore, a comprehensive analysis was carried out into the relationship between expression of four monoterpene synthesis genes and accumulation of main volatile monoterpenes and their acetic acid ester derivatives. The results showed that the genes RrDXS, RrDXR and RrLIS showed consistent expressions during the development process for R. rugosa flower from budding to withering stage, the overall expression levels of gene RrDXS and RrLIS were obviously lower as compared with those of gene RrDXR and RrAAT. Although the gene RrDXS, RrDXR, RrAAT and RrLIS were expressed in all parts of R. rugosa floral organs, the expression levels varied significantly. The variations in the constituent and content of volatile monoterpenes including citronellol, geraniol, nerol, linalool, citronellyl acetate, geranyl acetate and neryl acetate at different development stages and parts of floral organs were significantly different. On this basis, we concluded that the gene RrDXR and RrAAT might play a key role in the biosynthesis of volatile monoterpenes in R. rugosa flowers, and the two genes are important candidate genes for the regulation of secondary metabolism for rose aromatic components.
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Liguo
authors.initials: L
authors.lastname: Feng
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chen
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Tinglin
authors.initials: T
authors.lastname: Li
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tao
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China.
authors.forename: Daqiu
authors.initials: D
authors.lastname: Zhao
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, PR China. Electronic address: lxsheng@yzu.edu.cn.
authors.forename: Lixia
authors.initials: L
authors.lastname: Sheng
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D019747:Aldose-Ketose Isomerases / Q000235:genetics / Q000378:metabolism; D035264:Flowers / Q000201:enzymology / Q000378:metabolism*; D017343:Genes, Plant; D006836:Hydro-Lyases / Q000235:genetics / Q000378:metabolism; D039821:Monoterpenes / Q000378:metabolism*; D009812:Odorants; D010428:Pentosephosphates / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D027826:Rosa / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D064210:Secondary Metabolism / Q000235:genetics; D014166:Transferases / Q000235:genetics / Q000378:metabolism; D055549:Volatile Organic Compounds / Q000378:metabolism*
chemical_list: D039821:Monoterpenes; D010428:Pentosephosphates; D010940:Plant Proteins; D055549:Volatile Organic Compounds; C031625:xylulose-5-phosphate; C114231:1-deoxy-D-xylulose 5-phosphate reductoisomerase; D014166:Transferases; C109461:deoxyxylulose-5-phosphate synthase; D000217:Acyltransferases; D006836:Hydro-Lyases; C092055:S-linalool synthase; D019747:Aldose-Ketose Isomerases
keywords: Cloning; Flowery odour; Gene expression; Monoterpenes; R. rugosa