玉米亚硫酸氧化酶基因ZmSO的克隆及在二氧化硫胁迫下的表达分析  

Cloning of a Sulfite Oxidase Gene and Its Functional Expression in Maize(Zea mays L.) Under SO_2 Stress

作　　者：夏宗良[1] 武轲[1] 王永霞[2] 周朋[1] 丁俊强[2] 吴建宇[1] 

机构地区：[1]河南农业大学生命科学学院,郑州450002 [2]河南农业大学农学院,郑州450002

出　　处：《中国农业科学》2009年第8期2643-2651,共9页Scientia Agricultura Sinica

基　　金：国家"863"计划专项(2006AA10Z1D5);教育部科学技术重点项目(208080)

摘　　要：【目的】克隆玉米中的亚硫酸氧化酶(Sulfite Oxidase,SO)基因,明确其在SO2胁迫下的表达,为今后利用SO进行玉米抗环境污染(SO2、酸雨等)的遗传改良奠定基础。【方法】采用RT-PCR结合RACE技术克隆SO基因,并利用半定量RT-PCR技术分析其在SO2胁迫下的表达。【结果】从玉米自交系Q9中分离到SO基因的全长cDNA序列(GenBank登录号:FJ436404),命名为ZmSO。该基因的开放阅读框为1194bp,编码397个氨基酸。序列比对及结构预测分析表明,ZmSO编码的氨基酸序列与拟南芥、番茄、水稻中的氨基酸序列的相似性分别达到72%、74%和89%,且包含1个钼辅因子结合域、1个自身二聚化的结构域和1个过氧化物体靶信号序列。半定量RT-PCR分析显示,高浓度SO2胁迫后,在高抗系中ZmSO表达水平显著增高,而在高感系中无显著变化。【结论】分离获得的ZmSO与其它植物物种的SO具有较高的同源性,在高抗系中表达受SO2胁迫诱导增强,可能参与抗性系对SO2胁迫的响应和抗性反应过程。[Objective] Sulfite oxidase （SO） plays an important role in sulfur metabolism and sulfur dioxide detoxification in higher plants. To date, most reports on plant SO have focused on Arabidopsis, but little is known about SO in cereal crops such as maize. The objectives of this study are to clone the sulfite oxidase gene and to understand its expression in maize under SO2 stress. This study will provide a basis for genetic improvements in environmental pollutant tolerance （SO2 and acid rain） in maize. [Method] The SO gene from maize was cloned by RT-PCR and RACE, and its expression was analyzed under SO2 stress using semi-quantitative RT-PCR method. [ Result ] The full-length sulfite oxidase （SO） cDNA, named ZmSO （GenBank accession number FJ436404）, was cloned from an elite inbred Q9. The cDNA contains a 1 194-bp open reading frame （ORF） and encodes 397 amino acids. Sequence alignment and structure prediction showed that the deduced amino acid sequence of ZmSO shared 72%, 74%, and 89% similarities with homologs from other plants such as Arabidopsis thaliana, Lycopersicon esculentum and Oryza sativa, respectively. In addition, similar to other plant SO homologs, ZmSO also contained three conserved functional domains such as one Moco-binding domain, one dimerization domain and one peroxisome targeting signal. Semi-quantitative RT-PCR analysis demonstrated that ZmSO expression was up-regulated significantly in resistant inbred Q9 after treatment with higher concentration of SO2, but not in sensitive inbred Chang7-2. [ Conclusion ] its expression is up-regulated by S02 stress in the highly The isolated ZmSO from maize is orthologous to other plant species, and resistant line, indicating that the SO from maize may be involved in resistance responses of resistant maize plants to SO2 stress.

关 键 词：玉米 亚硫酸氧化酶 胁迫 表达 

分 类 号：S513[农业科学—作物学]