月季类胡萝卜素裂解双加氧酶基因RcCCD4在花香合成中的功能  

Functional Characterization of Carotenoid Cleavage Dioxygenases 4 Gene(RcCCD4)Involved in Biosynthetic Pathway of Floral Scent in Rosa chinensis‘Old Blush’

作　　者：付琪 王丹 景维坤[1] 张颢 王慧纯[1] 蹇洪英 邱显钦[1] 王其刚[1] 唐开学[1] 晏慧君[1] FU Qi;WANG Dan;JING Weikun;ZHANG Hao;WANG Huichun;JIAN Hongying;QIUXianqin;WANG Qigang;TANG Kaixue;YAN Huijun(Flower Research Institute of Yunnan Academy of Agricultural Sciences,Kunming 650051,China;Institute of Resource Plants,Yunnan University,Kunming 650500,China)

机构地区：[1]云南省农业科学院花卉研究所,昆明650051 [2]云南大学资源植物研究院,昆明650500

出　　处：《园艺学报》2025年第3期623-634,共12页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(32060693);云南省基础研究计划项目(202401AS070032,202401CF070046);云南省兴滇英才支持计划创新团队(202305AS350002)。

摘　　要：为揭示类胡萝卜素裂解双加氧酶(carotenoid cleavage dioxygenase,CCDs)在花香合成通路中的作用,以中国古老月季‘月月粉’(Rosa chinensis‘Old Blush’)为材料,在花瓣中克隆了RcCCD4并进行功能解析。RT-qPCR结果表明,RcCCD4主要在花瓣中表达,花蕾期表达水平较低,盛开期表达水平最高。RcCCD4蛋白定位于细胞质体中。构建了RcCCD4的原核表达载体,通过酶活性检测发现,RcCCD4可以特异性地切割β–胡萝卜素。进一步分析发现,通过病毒诱导的基因沉默RcCCD4可显著降低花瓣中二氢–β–紫罗兰酮含量,而瞬时过表达RcCCD4可显著提高花瓣中二氢–β–紫罗兰酮含量。以上结果说明RcCCD4可以特异性地裂解β–胡萝卜素,进而合成二氢–β–紫罗兰酮。To reveal the role of carotenoid cleavage dioxygenases(CCDs)in biosynthetic pathway of floral scent,RcCCD4 gene were cloned from the petals of Rosa chinensis‘Old Blush’and functionally characterized.RT-qPCR showed that RcCCD4 was mainly expressed in petals,with the highest expression level at the fully opening stage and lowest at the bud stage.Subcellular localization assays showed that RcCCD4 were located in the plastid.Moreover,a prokaryotic expression protein vector for RcCCD4 were constructed and found that the RcCCD4 enzyme can specifically cleaveβ-carotene substrates in vitro enzymatic activity assay.Virus-induced gene silencing(VIGS)further suggested that silencing of RcCCD4 significantly reduced the content of dihydro-β-ionone in petals,and RcCCD4 overexpression led to increase in dihydro-β-ionone content.These results indicated that RcCCD4 can specifically cleaveβ-carotene substrates,thereby synthesizing dihydro-β-ionone.

关 键 词：月季 花香 类胡萝卜素裂解双加氧酶 原核表达 病毒诱导的基因沉默 

分 类 号：S666.4[农业科学—果树学]