紫苏迷迭香酸合成酶基因片段克隆及表达  

Molecular cloning and expression analysis of rosmarinic acid synthase gene fragment from Perilla frutescens

作　　者：邬树伟[1] 吕晓玲[1] 郝磊[1] 魏曼[1] 赵京[1] 

机构地区：[1]天津科技大学食品工程与生物技术学院,天津300457

出　　处：《广东农业科学》2012年第20期134-138,共5页Guangdong Agricultural Sciences

摘　　要：迷迭香酸合成酶(Rosmarinic acid synthase,RAS)是迷迭香酸生物合成途径中催化合成迷迭香酸重要前体物质2-氧-(4-香豆酰)-3-(4-羟基苯)乳酸的关键酶。利用同源序列扩增方法成功获得了紫苏RAS基因cDNA片段,命名为PerRAS-1,该片段长353 bp,编码117个氨基酸(GenBank登录号:JQ824060.1)。通过氨基酸序列比对分析,发现其氨基酸序列与香蜂草、彩叶草和丹参RAS基因片段的相似度分别高达86.44%,83.05%和83.05%。RAS系统进化树分析表明PerRAS-1与唇形科植物的RAS亲缘关系较近。荧光实时定量PCR对目的基因的表达谱分析表明,PerRAS-1基因在紫苏根、茎和叶中均有表达,且在根中表达量最高。紫外线(UV-B)照射和过氧化氢(H2O2)处理紫苏叶片在一定程度上下调PerRAS-1基因在叶中的转录水平;茉莉酸甲酯(MeJA)在一定程度上上调PerRAS-1基因在叶中的转录水平。Rosmarinic acid synthase（RAS） is the key enzyme involved in the rosmarinic acid（RA）metabolic biosynthesis,it can catalyze the important precursor component 4-coumaroyl-4＇-hydroxyphenyll-actic acid.The cDNA fragment of RAS gene was firstly successfully isolated from Perilla frutescens by homologous sequence amplification.The fragment-length cDNA of RAS,designated as PerRAS-1,was 353 bp and encoded 117 amino acids（Accession NO.JQ824060.1）.The results of amino acid sequence analysis showed that the identity of the sequence of PerRAS-1 amino acid with that of Melissa officinalis,Solenostemon scutellarioides and Salvia miltiorrhiza was 86.44 %,83.05 % and 83.05 %,respectively.Phylogenetic tree analysis revealed that PerRAS-1 shared high homology with other known RASs from Lamiaceae plants.The quantitative fluorescence Real-Time PCR analysis showed that the constitutive expression of PreRAS-1 in root was much higher than that in leaf and stem.Further expression analysis indicated that the Ultraviolet-B radiation（UV-B）,H2O2 treatments could down-regulate the PerRAS-1 transcript level and MeJA treatment could up-regulate its transcription level in leaves compared with the control in some degree.

关 键 词：紫苏 迷迭香酸合成酶 同源扩增 表达分析 

分 类 号：Q786[生物学—分子生物学]