%0 Journal Article %T 不结球白菜过氧化还原蛋白基因Brc2-Cys Prx的克隆和表达分析 %A 刘世拓 %A 肖栋 %A 许玉超 %A 侯喜林 %A 徐玮玮 %A 韩克 %A 董慧杰 %A 胡春梅 %J 南京农业大学学报 %D 2017 %R 10.7685/jnau.201603040 %X [目的] 双半胱氨酸型硫氧还蛋白过氧化物酶Brc2-Cys Prx是过氧化还原蛋白Peroxiredoxins(Prxs)的亚家族。Prxs是植物抗氧化酶防御系统的成员,对清除植物体内活性氧具有重要作用。本文旨在克隆和研究Brc2-Cys Prx基因在不结球白菜处于不同胁迫条件下的表达模式。[方法] 以不结球白菜霜霉病抗病自交系‘苏州青’和霜霉病感病自交系‘矮脚黄’为试验材料,利用RACE技术克隆得到不结球白菜Brc2-Cys Prx基因。利用生物信息学方法对该基因进行信息学分析。采用qRT-PCR技术对不结球白菜叶片Brc2-Cys Prx基因在霜霉病菌侵染及NaCl、CdCl2、PEG6000和ABA等非生物胁迫处理条件下的表达模式进行研究。[结果] Brc2-Cys Prx基因的cDNA全长为999 bp,其中开放阅读框长度为810 bp,共编码270个氨基酸。该蛋白不存在信号肽序列,预测相对分子质量为28.15×103,理论等电点为5.87。不结球白菜Brc2-Cys Prx蛋白的二级结构主要由α-螺旋和无规则卷曲构成。该蛋白含有1个PRX_Typ2cys结构域,属于硫氧还蛋白超家族。系统进化分析表明:不结球白菜Brc2-Cys Prx蛋白与同属植物的进化关系相近,其中与大白菜和甘蓝型油菜进化关系最近。霜霉病菌侵染条件下,Brc2-Cys Prx基因表达呈逐渐上调趋势,在‘矮脚黄’中的表达与‘苏州青’相比上调迟钝,且该基因在‘矮脚黄’中的表达量一直低于‘苏州青’。0.2 mol?L-1 NaCl和200 g?L-1 PEG6000处理抑制Brc2-Cys Prx基因的表达;150 μmol?L-1 CdCl2处理促进Brc2-Cys Prx基因的表达,在24 h达到最大值;100 μmol?L-1 ABA处理后,Brc2-Cys Prx基因表达上调,而12 h后,表达受抑制。[结论] 霜霉病菌侵染条件下,Brc2-Cys Prx在抗性系‘苏州青’和感病系‘矮脚黄’中的表达存在差异,并且在抗病系中的表达量较高,推测Brc2-Cys Prx基因的高转录水平是抗病品种较之感病品种对霜霉病菌侵染具有更高抗性的原因之一。在非生物胁迫条件下,Brc2-Cys Prx基因具有不同的应答模式,推测可能是涉及到不同的物质或信号途径的原因。</br>[Objectives] Brc2-Cys Prx is the subfamily of Prxs,which are members of the enzymatic antioxidant defense system of plants and plays an important role in scavenging reactive oxygen species(ROS) in plants. Cloning and characterization of Brc2-Cys Prx from non-heading Chinese cabbage are significant for research antioxidant defense genes expression patterns of non-heading Chinese cabbage. [Methods] In this study,with non-heading Chinese cabbage inbred resistance ‘Suzhouqing’ and susceptible inbred ‘Aijiaohuang’ as experimental materials,Brc2-Cys Prx gene was obtained using RACE technology. A series of bioinformatics software was used to speculate acid sequence and its nucleotide sequence of Brc2-Cys Prx. Under downy mildew infection and different abiotic stresses(NaCl,PEG6000,CdCl2 and ABA),gene expression patterns of Brc2-Cys Prx were investigated by using real-time quantitative RT-PCR in leaves. [Results] The full length CDS of Brc2-Cys Prx gene was 999 bp,containing an 810 bp open reading frame to encode a total of 270 amino acid residues. Meanwhile,the Brc2-Cys Prx protein from non-heading Chinese cabbage had no signal peptide sequence. Prediction of the relative molecular mass of Brc2-Cys Prx was 28.15×103 with the theoretical isoelectric point of 5.87. The two-dimension structure of Brc2-Cys Prx protein mainly consisted of α-helixes and random coils. Brc2-Cys Prx protein contained a PRX_Typ2cys domain and it belongs to thioredoxin superfamily. Homology analysis showed that the homologous species should be mainly belong to the cruciferae,and the Brc2-Cys Prx from non-heading %K 不结球白菜 %K 霜霉病菌 %K 活性氧 %K 抗氧化防御系统 %K Brc2-Cys Prx基因 %K 基因表达< %K /br> %K non-heading Chinese cabbage %K downy mildew %K reactive oxygen species %K antioxidant defense system %K Brc2-Cys Prx gene %K gene expression %U http://nauxb.njau.edu.cn/oa/darticle.aspx?type=view&id=201701006