思茅松1-脱氧-D-木酮糖-5-磷酸合酶(DXS)基因的克隆及功能分析  

Identification and Characterization of a 1-Deoxy-D-xylulose 5-phosphate Synthase Gene From Pinus kesiya var. langbianensis

作　　者：王毅[1,2] 周旭[3] 毕玮[1,2] 杨宇明[2] 李江[2] 王娟[2] 

机构地区：[1]云南省林业科学院国家林业局云南珍稀濒特森林植物繁育和保护重点实验室,云南昆明650201 [2]云南省林业科学院,云南省森林植物培育与开发利用重点实验室,云南昆明650201 [3]西南林业大学,云南昆明650224

出　　处：《林业科学研究》2015年第6期833-838,共6页Forest Research

基　　金：林业公益性行业科研专项(201304105)资助;云南省应用基础研究重点项目(2013FA054);云南省中青年学术技术带头人后备人才培养项目(2010CI016)资助

摘　　要：1-脱氧-D-木酮糖-5-磷酸合酶(DXS)是甲基–D–赤藓醇–4–磷酸(MEP)途径中的第一个酶,也是限速酶。本文根据思茅松(Pinus kesiya var.langbianensis(A.Chev.)Gaussen)树皮转录组数据分析结果,获得思茅松DXS基因片段,然后根据获得的基因片段设计特异引物,运用RT-PCR和RACE技术从思茅松树皮中克隆得到完整的DXS基因(Pk DXS1)。Pk DXS1基因的c DNA全长序列2 888 bp,含有1个2 223 bp的开放阅读框(ORF),编码740个氨基酸,该基因推断的蛋白与赤松(Pinus densiflora Siebold&Zucc)DXS蛋白的相似性为99%,与欧洲云杉(Picea abies(L.)H.Karst.)DXS的相似性为97%;经氨基酸序列比对,推断思茅松DXS具有高等植物DXS酶特有的叶绿体转运肽,二磷酸硫胺结合位点和转酮醇酶结构域。半定量RT-PCR检测表明树皮的创伤促进DXS基因的表达。l-deoxy-D-xylulose 5-phosphate synthase（DXS） catalyzes the first and the rate-limiting step of the MEP pathway. In this study, the special primers were designed according to the transcriptome data of Pinus kesiya var. langbianensis （A. Chev. ） Gaussen. The full length gene of PkDXS1 was cloned by RT-PCR and RACE, which consisted of 2223 bp open reading frame （ORF） encoding 740 amino acid, the deduced PkDXSI protein shared 99% and 97% identities with DXS of Pinus densiflora Siebold ＆ Zucc and Picea abies （ L. ） H. Karst. , respective- ly. Analysis of the deduced amino acid sequence showed that PkDXS1 carried a chloroplast transit peptied, a thia- mine diphosphate binding site, and a transketolase motif, which are the important characteristics of DXS enzymes in higher plants. Semiquantity-RT-PCR detection showed that DXS gene expression was up-regulated by wounding treatment.

关 键 词：思茅松 DXS CDNA克隆 基因功能分析 

分 类 号：S718.46[农业科学—林学]