枇杷有色体特异番茄红素β-环化酶基因的克隆及表达分析  

Analysis of Cloning and Expression of Chromoplast-specific Lycopeneβ-cyclase in Eriobotrya japonica Lindl.

作　　者：池卓恒 王永清[1] 洪敏[1] 邓群仙 张卉 杨赟淼 Chi Zhuoheng;Wang Yongqing;Hong Min;Deng Qunxian;Zhang Hu;Yang Yunmiao(College of Horticulture,Sichuan Agriculture University,Chengdu,611130)

机构地区：[1]四川农业大学园艺学院,成都611130

出　　处：《基因组学与应用生物学》2020年第11期5207-5213,共7页Genomics and Applied Biology

基　　金：四川省科技支撑计划项目(2016NYZ0-034)资助。

摘　　要：为了解枇杷有色体特异番茄红素β-环化酶基因(CYC-B)的序列及表达特点,本研究以‘大五星’(红肉)和‘川农1-5-9’(白肉)枇杷为材料,采用同源克隆法,从枇杷果实中克隆了类胡萝卜素生物合成途径中关键酶基因之一(CYC-B的c DNA全长序列),运用生物学软件对该序列及推导的氨基酸序列进行相关生物信息学分析,同时利用荧光定量PCR技术探究CYC-B基因在枇杷果实不同发育时期的表达模式。结果显示,该基因全长1579 bp,具有1491 bp的完整开放阅读框,编码496个氨基酸。氨基酸同源性分析表明,该基因编码的氨基酸序列与白梨(XP009377819.1)和苹果(Malus domestica)CYC-B基因(XP008361015.1)的同源性分别高达98%和97%,由此推测这个基因属于枇杷CYC-B基因(EjCYC-B)。荧光定量PCR分析结果表明,随着枇杷果实的发育,EjCYC-B的表达量明显增加,且不同发育阶段EjCYC-B基因的表达存在显著变化;其中,在果皮和果肉中的表达分别在黄熟期和成熟期达到最高峰。因此可以推测,EjCYCB在枇杷类胡萝卜素合成中,参与调控,并存在一定的作用机理,使得枇杷的果皮、果肉在不同发育阶段的呈色不同。本研究结果可为深入认识CYC-B调控类胡萝卜素合成机理提供基础。To understand the characteristics of sequences and expression of Chromoplast-specific lycopeneβ-cyclase(CYC-B)in Eriobotrya japonica Lindl.,CYC-B,one of the key enzymes genes of carotenoid biosynthesis pathway,Was cloned from loquat peel and pulp by RT-PCR using’Dawuxing’(Red flesh)and’Chuannong 1-5-9’(White flesh)for experimental material in this study.And bioinformatics methods were used to analyze the cDNA sequence and putative amino acid sequence.Meanwhile,Real-time PCR were employed to study the expression mode of CYC-B gene in different developmental stages.The result showed that the full-length sequence consisted of 1579 bp with an intact open reading frame of 1491 bp which encoded 496 amino acids.Homology analysis indicated that the deduced CYC-B protein was highly homologous to pear(Pyrus x bretschneideri)andapple(Malus domestica)with similarities of 97%and 98%respectively,which evidenced that the cloned gene belonged to CYC-B in Eriobotrya japonica Lindl.(EjCYC-B).Analysis of Real-time PCR showed that the expression of EjCYC-B gene not only increased but also changed significantly at different developmental stages among which expression of EjCYC-B in peel and pulp reached the peak at yellow mature stage and full mature stage respectively.Therefore,it can be speculated that EjCYC-B is involved in the regulation of carotenoid biosynthesis,and there is a certain mechanism,which makes the peel and pulp of loquat present different colors at different development stages.The result of this study could provide the basis for better understanding carotenoid synthesis mechanism with CYC-B regulation.

关 键 词：枇杷CYC-B基因克隆 基因表达 

分 类 号：S667.3[农业科学—果树学]