玫瑰单萜类花香成分的代谢调控研究

玫瑰是优良的园林绿化材料和珍贵的天然香料植物，玫瑰精油被誉为"液体黄金"，经济和保健价值极高。单萜类化合物中的香茅醇、香叶醇、橙花醇及其乙酸酯类衍生物是玫瑰鲜花和精油的主要芳香成分，采用基因工程手段调控单萜类代谢途径，开展以提高玫瑰精油含量为目标的代谢工程研究具有重要的理论意义和应用价值。本项目拟在前期研究的基础上，选择与玫瑰单萜代谢相关的RrDXR、RrGES和RrAAT为调控靶基因，克隆其启动子，找出各自的顺式作用元件及其序列；以该序列为诱饵，利用酵母单杂交系统筛选调控玫瑰单萜代谢的转录因子，研究其时空表达模式和调控功能；分别构建三个靶基因及转录因子基因的过表达载体，农杆菌介导遗传转化矮牵牛，验证并比较过表达合成基因及转录因子对单萜类化合物含量的影响。从而丰富植物萜类代谢与调控理论，并有望获得具有玫瑰香味的矮牵牛，为接下来创制"高油"玫瑰新种质及其它商品花卉香气品质的分子改良奠定基础。

Rose (Rosa rugosa) is an excellent landscaping material and a precious natural perfume plants. Rose essential oil is known as 'liquid gold' and has high economic and health values. Citronellol, geraniol, and nerol in monoterpenes, as well as their acetic ester derivatives are the main fragrant components of rose flower and essential oil. The regulation and modification of the metabolic pathways of these monoterpenes by genetic and metabolic engineering aimed at improving the content of rose essential oil will have important theoretical and practical significance. Based on the partial genes related to rose monoterpene metabolism cloned at an early stage, RrDXR, RrGES, and RrAAT will be used as the controlling target genes. The cis-acting element sequence will then be identified and analyzed by genome walking to separate the promoter subsequence. With this sequence as bait, the transcription factors involved in rose monoterpene metabolism shall be screened using the yeast one-hybrid system, its temporal and spatial expression patterns and biological functions will then be analyzed. Subsequently, gene overexpression vectors shall be constructed based on agrobacterium-mediated genetics to transform petunias. The purpose is to verify the influence of overexpressing synthesis genes and transcription factor on the content of monoterpenes. Therefore, this study will be able to enrich knowledge on plant terpenoids metabolism and regulation theories. We also expect to be able to create petunias with the smell of rose and new species of Rosa rugosa with improved essential oil content. Genetic resources for the molecular improvement of the aroma quality of some other commercial flowers shall be provided as well.