枣木葡聚糖转移酶基因的表达分析  

Cloning and expression analysis of xyloglucan endotransglucosy-lase/hydrolase(XTH) gene in jujube fruit

作　　者：吕燕荣[1] 任小林[1] 

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《果树学报》2011年第6期998-1004,共7页Journal of Fruit Science

基　　金：国家苹果产业技术体系专项(nycytx-08-05-02)

摘　　要：为研究木葡聚糖内糖基转移酶(XTH)与枣果实生长及成熟软化的关系,采用普通PCR及3’RACE扩增技术,从鲜枣品种梨枣和沾化冬枣中均克隆到XTH基因的部分序列;同时,利用实时荧光定量PCR技术,研究了2个鲜枣品种的不同生长期其采后常温贮藏过程中XTH基因的相对表达量的变化。结果表明,从梨枣和沾化冬枣中克隆的XTH基因片段均为776 bp,包含636 bp的开放阅读框,编码212个氨基酸,分别命名为ZjXTH1和ZjXTH2(登录号分别为:HQ896312和HQ896313)。通过Blastn和Blastp对序列同源性进行比对分析,ZjXTH基因与已登录的其他物种的XTH基因相似性在68%～78%。实时定量PCR表达分析表明,ZjXTH基因的表达从盛花后51 d开始积累,并且在枣果实成熟软化过程中的表达量显著高于果实的生长期。梨枣ZjXTH1基因在采后贮藏中呈现"上升-下降-上升"的变化规律,在果实转为全红以及后期迅速软化时表达量均较高。沾化冬枣ZjXTH2基因在采后贮藏中呈现先上升后下降的趋势,在果实转为全红时表达量最高。研究结果说明,XTH基因在枣果实的成熟软化中可能起着一定的促进作用。In order to study the relationship of Xyloglucan endotransglucosylase/hydrolase （XTH） and fruit growth and softening in two jujube （Ziziphus jujuba M.） cultivars, Li jujube and Zhanhua Dong jujube, two partial XTH cDNA sequences were obtained by 3 RACE, and the expression of XTH genes during fruit growth and ripening at the room temperature was investigated by real-time quantitative PCR （RT-qPCR）approach. The results showed that, the two partial XTH cDNA sequences named ZJXTH1 （Gen- Bank accession number： HQ896312） and ZJXTH2 （GenBank accession number： HQ896313） were 776bp, containing 636 bp ORF and coding 212 amino acids. The results of homologous analysis in GenBank demonstrated that the ZJXTH sequences were 68% to 78% identical with those of other plants on the nucleotide sequences and the deduced amino acid sequences. The expression of ZJXTH genes accumulated since 51 days after flowering in both jujube cultivars and was markedly higher during the fruit ripen and storage than the growth period. The ZJXTH1 expression displayed up-down-up trend during the storage, and the maximums appeared in the fruit turning red and rapidly softening period. The ZJXTH2 expression displayed up-down trend during the storage, and the maximum appeared in the fruit turning red period. All these results suggest that the XTH gene might play a promoting role in the jujube fruit ripeness and softening process.

关 键 词：枣果实 XTH基因 实时荧光定量PCR 

分 类 号：S665.1[农业科学—果树学]