茶树DNA甲基转移酶基因CsDRM2的克隆及表达分析  

Cloning and Expression Analysis on DNA Methyltransferase Gene, CsDRM2, of Camellia sinensis

作　　者：周艳华[1] 曹红利[1] 岳川[1] 王璐[1] 郝心愿[1] 王新超[1] 杨亚军[1] 

机构地区：[1]中国农业科学院茶叶研究所/农业部茶树生物学与资源利用重点实验室/国家茶树改良中心,浙江杭州310008

出　　处：《茶叶学报》2015年第1期1-7,共7页Acta Tea Sinica

基　　金：国家自然科学基金(31170650);国家茶叶产业技术体系(CARS-23);浙江省农业新品种选育重大专项(2012C2905-3)

摘　　要：DNA甲基化作为表观遗传修饰的主要途径之一,能够通过对基因组DNA的修饰参与植物对外界环境胁迫的响应,DNA甲基化需要DNA甲基转移酶的参与。实验室前期研究表明,茶树在冷驯化过程中发生了甲基化反应。通过RACE克隆,获得了茶树中DNA甲基转移酶Cs DRM2基因的c DNA全长序列(NCBI登录号KR057963)。Cs DRM2序列全长2328bp,含1815bp的开放阅读框,编码604个氨基酸,预测蛋白质分子量为67.39 k D,理论等电点(PI)为4.85。生物信息学分析结果显示,茶树Cs DRM2蛋白与芝麻和烟草的亲缘关系最近,Cs DRM2的氨基酸序列与其他植物的DRM2相似性均高于65%。Cs DRM2基因表达分析的结果发现,随着冷驯化的进行,Cs DRM2基因的表达量呈现出增加的趋势,参与茶树冷驯化过程的甲基化响应。As one of the major pathways of epigenetic regulation, DNA methylation can modify genomic DNA and take part in responding to the environmental stresses of the plants. The process requires the involvement of DNA methyltransferase. It was found, in our previous study, to occur during the cold acclimation. In this study, a full-length cDNA sequence of CsDRM2 gene was obtained using the RACE technique. Subsequently, it was submitted to NCBI and assigned an accession number of KR057963. The cDNA length of CsDRM2 was 2,328 bp containing a 1,815 bp open reading frame and the encoding 604 amino acid residues. The predicted molecular weight was 67.39 kD and theoretical isoelectric point pH 4.85. The comparison on their sequences showed a similarity greater than 65% between CsDRM2 and other reported DRMs. The phylogenetic tree analysis on CsDRM2 indicated its close genetic relationships with Sesamum indicum and Nicotiana tabacum. The qRT-PCR results on CsDRM2 revealed differential expressions of the gene at different stages of the cold acclimation. It suggested that CsDRM2 participated in the DNA methylation of the tea plant in response to cold stress.

关 键 词：茶树 DNA甲基转移酶基因CsDRM2 克隆 表达分析 冷驯化 

分 类 号：S571.1[农业科学—茶叶生产加工]