胡萝卜肉桂醇脱氢酶基因的克隆及其对非生物胁迫的响应

摘要

该实验采用RT-PCR技术，从胡萝卜‘黑田五寸’中克隆获得了编码肉桂醇脱氢酶（Cinnamyl alcohol dehy-drogenase ，CAD）的基因 DcCA D。 DcCA D序列长1074 bp ，编码357个氨基酸。亲水／疏水性分析表明，DcCAD属于亲水性蛋白。系统进化分析显示，DcCAD与番茄CAD（XP＿010314515．1）亲缘关系最近。荧光定量PCR结果显示，DcCA D基因在胡萝卜根、叶片和叶柄中的表达量差异显著，其相对表达量为叶片＞根＞叶柄。 DcCA D基因对高温（38℃）、低温（4℃）、干旱（20％ PEG）和盐（0．2 mol・L －1 NaCl）胁迫均有响应，尤其对高温胁迫和低温胁迫响应明显，而且高温处理后1 h和低温处理后2 h表达量最高。研究推测，DcCA D基因对胡萝卜抗逆性具有一定的作用。%Here ,the gene encoding DcCAD were cloned from carrot cultivar ‘Kurodagosun’ with RT-PCR method .The length of DcCA D was 1 074 bp ,and encoding 357 amino acids .The DcCAD may belong to hydrophilic protein . Phylogenetic analysis showed that DcCAD closed to CAD from tomato (XP_010314515 .1) .Quantitative real-time PCR analysis showed that the expression profiles of the DcCA D gene are significantly different in different tissues (root ,leaf blade ,and petiole) of carrot .Relative expression level of the DcCA D gene is leaf blade> root> petiole .The DcCA D gene is responsive to various abiotic stresses ,such as heat (38 ℃) ,cold (4 ℃) ,drought (20% PEG) and salt (0 .2 mol・L -1 NaCl) .The ex-pression level was significantly increased after high temperature or low temperature treatments ,respective-ly .The expression levels peaked at 1 h heat treatment and 2 h cold treatment ,respectively .These results suggested that DcCA D gene participate in the response process of carrot under the abiotic stress .