洋葱黄酮醇合成酶基因的克隆与表达分析  

Cloning and Expression Analysis of Flavonol Synthase Gene in Onion

作　　者：王振宝[1] 杨妍妍[1] 刘冰江[1] 霍雨猛[1] 李艳伟 孙亚玲[1] 吴雄[1] Wang Zhenbao;Yang Yanyan;Liu Bingjiang;Huo Yumeng;Li Yanwei;Sun Yaling;Wu Xiong(Vegetable Research Institute,Shandong Academy of Agricultural Sciences,Jinan 250100,China)

机构地区：[1]山东省农业科学院蔬菜研究所,山东济南250100

出　　处：《山东农业科学》2022年第12期18-24,共7页Shandong Agricultural Sciences

基　　金：财政部和农业农村部国家现代农业产业技术体系项目(CARS-24-A-10)。

摘　　要：黄酮醇合成酶(flavonol synthase, FLS)是植物黄酮醇生物合成途径中的关键酶。本研究克隆了洋葱黄酮醇合成酶基因AcFLS,其编码序列长度为927 bp,编码309个氨基酸。AcFLS蛋白为亲水性胞质不稳定蛋白,二级结构以无规则卷曲和α-螺旋为主,属于α-同戊二酸和二价铁离子依赖型加氧酶家族。AcFLS的氨基酸序列与洋葱、虎眼万年青、石刁柏FLs蛋白的同源性分别为91.34%、76.42%、74.63%。实时定量PCR结果显示,AcFLS基因在洋葱中的表达具有组织特异性,表现为叶鞘中表达量最高,叶片次之,根中极少表达;在鳞茎膨大过程中AcFLS基因的表达量呈先升高后降低的趋势,在膨大盛期达到最高值;但AcFLS基因在紫皮、黄皮洋葱中的表达水平并无显著差异。该研究为进一步探明洋葱鳞茎颜色产生的机理奠定了基础。Flavonol synthase(FLS) is a key enzyme in the pathway of flavonol biosynthesis. In this study, the flavonol synthase gene in onion(AcFLS) was cloned. The length of AcFLS gene was 927 bp, and it encoded 309 amino acids. AcFLS was a hydrophilic and unstable protein which located in cytoplasm. It’s secondary structure mainly consisted of random coil and α-helix. Conserved domain analysis showed that AcFLS protein belonged to dioxynase family, whose activity depended on the co-existence of α-ketoglutaric acid and ferrousion. The homology of AcFLS amino acid sequence with Allium cepa, Albuca bracteata and Asparagus officinalis were 91.34%, 76.42% and 74.63%, respectively. The results of real-time PCR showed that AcFLS was a tissue specific gene in onion, and it had the highest expression level in leaf sheath, followed by leaves, but rarely in roots. At the development stages of onion bulbs, it showed a trend of increasing firstly and then decreasing and reached the highest level at the full expansion period of bulb. However, there was no significant difference in the expression level of AcFLS gene between purple and yellow onion. This study laid foundations for further understanding the occurrence mechanism of onion bulb color.

关 键 词：洋葱 黄酮醇合成酶 基因克隆 生物信息学分析 表达分析 

分 类 号：S633.2[农业科学—蔬菜学] Q78[农业科学—园艺学]