月季花香不仅是重要的观赏性状，而且具有重要的经济价值。由于传统杂交育种的局限性、花香代谢途径复杂等原因，使得大多数现代月季不具有香味。项目组在前期研究中对月月粉进行了转录组测序，从中选取了花香关键酶基因进行不同组织部位的表达分析，获得了主要在雄蕊、花瓣中表达的基因RcEGS和RcAAT。在此基础上，本项目拟采用qRT-PCR方法，对RcEGS和RcAAT基因进行月月粉花不同发育时期表达分析；采用RACE方法克隆全长cDNA；利用Gateway克隆技术构建原核表达载体,获得重组表达蛋白并进行蛋白纯化，通过体外酶与底物特异反应进行酶活性鉴定及GC/MS分析；构建植物表达载体并转化月季，获得转基因植株并进行其香味成分分析，进一步明确RcEGS和RcAAT基因参与合成的香味成分。研究结果不仅有助于探明RcEGS和RcAAT基因在花香合成代谢途径上的作用，还可为培育具有香味的月季品种提供候选基因。

Rose scent is not only an important ornamental trait, but also serviced economically value as a source of natural fragrance and flavour. Due to the limit of traditional cross-breeding and the complexity of scent-related metabolic pathway, fragrance seems to have been largely lost during the later stages of breeding process.In our previous study,using the high-throughput transcriptome sequencing technology, 89,614 Unigenes from Rose chinensis 'Pallida' were obtained, among which 307 Unigenes were invovled in scent biosynthesis. Some scent-related genes were selected to analyze expression by qRT-PCR, and RcEGS and RcAAT were found many expressed in stamens and petals of R. chinensis 'Pallida',respectively. According to the above achievements, the current study will perform expressional analysis of RcEGS and RcAAT in different flower developmental stages by qRT-PCR, and test the volatile compounds,respectively. Furtherly, the full-length cDNA of RcEGS and RcAAT will be obtained by RACE technology.Then, prokaryotic expression vector pDEST17-RcEGS and pDEST17-RcAAT will be constructed by Gateway cloning technology to get heterologous recombinant protein expression in E.coli and purification. Next,the functions will be identified by in vitro enzyme activities of RcEGS and RcAAT in the presence of substrates coniferyl acetate and geraniol,and by GC/MS analysis,respectively. Finally,plant expression vectors of RcEGS and RcAAT will be constructed, and their functions will be furtherly performed by genetic transformation to roses and analysis of genetially modified roses. These results can not only lay a foundation for the research of synthesis pathway of key synthase genes in rose, but also provide candidate genes for rose-scent breeding.