胡萝卜抗坏血酸过氧化物酶基因的分离及其对非生物胁迫的响应  

Cloning of the gene encoding ascorbate peroxidase from carrot and its response to abiotic stress

作　　者：张馨月[1] 王广龙[1] 黄蔚[1] 王枫[1] 倪桢燚 熊爱生[1] 

机构地区：[1]南京农业大学园艺学院/作物遗传与种质创新国家重点实验室/农业部华东地区园艺作物生物学与种质创制重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2016年第1期55-62,共8页Journal of Nanjing Agricultural University

基　　金：教育部新世纪优秀人才支持计划项目(NCET-11-0670);江苏省杰出青年基金项目(BK20130027);江苏高校优势学科建设项目(2011PAPD)

摘　　要：[目的]抗坏血酸过氧化物酶(APX)利用抗坏血酸作为电子供体,清除植物中的过氧化物,在植物应对非生物胁迫中起重要作用。本文目的是研究胡萝卜Dc APX基因在抵御逆境胁迫过程中的响应情况。[方法]以胡萝卜‘黑田五寸’为研究材料,克隆获得胡萝卜Dc APX基因(Gen Bank登录号为KR364573),对该基因进行序列分析,并研究其主要非生物胁迫(高温、低温、干旱和盐胁迫)下的基因表达情况。[结果]序列分析表明,胡萝卜Dc APX基因全长753个碱基,编码250个氨基酸,预估其蛋白质相对分子质量为27.76×103,p I值5.65。进化分析表明,胡萝卜Dc APX在进化关系上与同属伞形科的短果茴芹同源性最高。空间结构分析表明,胡萝卜Dc APX的氨基酸二级结构由38.40%的α-螺旋、10.40%的延伸主链和51.20%的随机卷曲构成。胡萝卜Dc APX的氨基酸三级结构由10个α-螺旋和4个β-折叠构成。实时荧光定量PCR结果显示,胡萝卜‘黑田五寸’中Dc APX基因表达具有组织特异性,在叶中表达量最高。[结论]胡萝卜中Dc APX基因可以响应多种非生物逆境胁迫,在胡萝卜非生物逆境胁迫调控过程中起着重要作用。[Objectives]Ascorbate peroxidase（ APX） removes excess plant peroxides by using an electron donor from ascorbic acid,which is an essential mechanism in response to abiotic stress. The aim of the paper is to study the response of Dc APX gene in the process of resisitance to abiotic stress. [Methods]The Dc APX gene was cloned from carrot variety‘Kurodagosun＇. Expression profiles under high and low temperature,drought,and salinity treatments were performed to further understand the roles of the gene in response to abiotic stress in carrot. The gene was submitted to Gen Bank and the accession number is KR364573. [Results]Sequence analysis indicated that the length of Dc APX gene was 753 bp,which encoded 250 amino acids. It is predicted that the relative molecular mass of its protein was 27. 76 × 103,and p I was 5. 65. Amino acid sequence comparison showed that the evolutionary relationship of Dc APX from carrot was close to Pimpinella brachycarpa,which both belong to the Apiaceae family. Structure analysis showed that Dc APX was made up of 38. 40% alpha helix,10. 40% extended strand,and 51. 20% random coil. Analysis on threedimension structure implied that the enzyme was composed of 10 alpha helixes and 4 beta sheets. Quantitative real-time PCR analysis demonstrated that carrot Dc APX gene was tissue-specific,and had the highest expression level in the leaf. [Conclusions]Dc APX gene was significantly induced by abiotic stress,and the gene may play important roles in resistance against abiotic stress.

关 键 词：抗坏血酸过氧化物酶 基因克隆 非生物胁迫 表达分析 胡萝卜 

分 类 号：S631.2[农业科学—蔬菜学]