中文摘要：

利用RACE技术从‘陇油6号’油菜中克隆得到一个新的RbohB基因,全长2 694 bp,开放阅读框2 541bp,编码846个氨基酸。实时荧光定量PCR分析表明RbohB基因表达受低温、高盐、H_2O_2诱导,MAPKK抑制剂U0126预处理12 h再经低温、高盐、H_2O_2诱导,与单独处理结果相比,RbohB基因表达明显降低,表明该基因在油菜适应低温、高盐、H_2O_2胁迫过程中发挥作用,U0126对该基因的转录有抑制作用。NADPH氧化酶活性受H_2O_2处理的诱导,U0126预处理12 h再经H_2O_2处理,与单独H_2O_2处理结果相比,NADPH氧化酶活性明显降低,表明MAPKK抑制剂U0126对该酶活性有抑制作用。

英文摘要：

A novel RbohB gene was isolated from Brassica campestris L. Longyou 6 by RACE. The full-length cDNA of RbohB is 2 694 bp,with open reading frame（ ORF） 2 541 bp,encoding a 846 amino acid protein. By RT-PCR analysis,transcript level of RbohB was increased in response to cold,high salt and H_2O_2 stress.However,MAPKK inhibitor U0126 pretreatment 12 h before cold,high salt and H_2O_2 stress,compared with the single stress,the expression level of RbohB was significantly decreasing. The results suggested that RbohB played an important role during cold,high salt and H_2O_2 stress in B. campestris L. and U0126 has inhibitory effect to RbohB gene transcription. The activity level of NADPH oxidase was increased in response to H_2O_2 stress. However,U0126 pretreatment 12 h before H_2O_2 stress,compared with the single H_2O_2 stress,NADPH oxidase activity was significantly decreasing. The result showed that MAPKK inhibitor U0126 has inhibitory effect to NADPH oxidase activity.