紫色马铃薯查尔酮合成酶基因(CHS)的克隆及分析  

Cloning and Expression Analysis of a Chalcone Synthase(CHS) Gene from Purple Potato(Solanum tuberosum)

作　　者：胡朝阳[1] 周友凤[1] 龚一富[1] 金思[1] 王何瑜[1] 赵群芬[1] 

机构地区：[1]宁波大学海洋学院/教育部应用海洋生物重点实验室,浙江宁波315211

出　　处：《中国农业科学》2012年第5期832-839,共8页Scientia Agricultura Sinica

基　　金：宁波市农业创新创业资金(2010C91050);宁波市农业科技攻关(2010C10051;2010C10057);宁波大学学科项目(XKL121;XKL11D2099);宁波市科技林特与食品加工科技特派团队项目

摘　　要：【目的】从紫色马铃薯中克隆CHS的cDNA全长序列,并分析其组织表达水平以及诱导剂处理后基因的表达与花青素含量积累之间的关系。【方法】采用RT-PCR和RACE方法克隆紫色马铃薯CHS的cDNA全长序列,通过在线软件进行核苷酸序列和氨基酸序列分析,半定量RT-PCR检测StCHS在紫色马铃薯组织中的表达特异性以及蔗糖和赤霉素处理后StCHS的表达。采用分光光度计法测定紫色马铃薯花青素含量。【结果】克隆获得紫色马铃薯CHS的cDNA全长1 490 bp,包含1 170 bp的ORF,该基因编码389个氨基酸。推测StCHS蛋白含有Cys164、Phe215、His303和Asn3364个活性位点,构成CHS蛋白的催化中心。StCHS的表达具有组织特异性,在茎、叶柄和叶中表达较强,在根、块茎和叶轴中几乎检测不到CHS的表达。赤霉素能促进CHS的表达从而促进花青素的积累;蔗糖能够显著促进紫色马铃薯花青素的积累,但对CHS的表达影响不明显。【结论】从紫色马铃薯中克隆获得CHS的cDNA全长序列,该基因表达具有组织特异性,StCHS是紫色马铃薯花青素合成途径中的一个限速酶基因。【Objective】 The aim of this study was to clone the full length cDNA of chalcone synthase from purple potato,to analyze its expression at different organs and the relationship between CHS expression and anthocyanin accumulation after treated with different concentrations of GA3 and sucrose.【Method】 The full-length cDNA of CHS was isolated from Solanum tuberosum by RT-PCR and RACE.Semi-quantitative RT-PCR was used to analyze the expression levels of StCHS in different organs,and the expression levels induced by GA3 and sucrose were adopted by semi-quantitative RT-PCR.The anthocyanin content of purple potato was measured by spectrophotometer method.【Result】 The cloned full-length CHS was 1 490 bp in length,containing a 1 170 bp open reading frame(ORF),which encodes 389 amino acids.The deduced amino acids contained Cys164,Phe215,His303,and Asn336 active sites,which constitute the catalytic center of CHS.CHS is expressed at different levels in different organs,which was found to be expressed in stems,leaf stalks and leaves but not in roots,tubers or rachises.The anthocyanin accumulation was slightly induced by GA3 as well as the expression of CHS.The anthocyanin accumulation was strongly induced by sucrose,but the CHS expression was not notably induced.【Conclusion】CHS gene was cloned from purple potato and its expression is tissue-specific.StCHS is a rate-limited gene in the flavonoid synthesis pathway of purple potato.

关 键 词：紫色马铃薯 查耳酮合成酶基因 花青素 赤霉素 蔗糖 基因表达 

分 类 号：S532[农业科学—作物学]