rd29A和CaMV-35S启动子调控转AtDREB2A苜蓿耐碱性分析  

Alkaline tolerance analysis of transgenic alfalfa with AtDREB2A gene regulated by rd29A and CaMV-35S promoter

作　　者：才华[1] 宋婷婷[1] 张大洋[1] 

机构地区：[1]东北农业大学生命科学学院,哈尔滨150030

出　　处：《东北农业大学学报》2016年第9期16-23,共8页Journal of Northeast Agricultural University

基　　金：教育部高等学校博士学科专项科研基金(20132325120017);国家自然科学青年基金项目(31302022)

摘　　要：rd29A和CaMV-35S启动子广泛应用于植物基因工程中,但调控效果在不同转基因植物中不同。文章采用Real-time PCR分析转基因各株系中AtDREB2A基因表达差异;对苜蓿扦插苗及一年生转基因苜蓿成苗分别作50 mmol·L^(-1)NaHCO_3(pH 8.0)和混合盐碱土(pH 9.3)处理,统计苜蓿各株系成活率、开花植株数,测定叶绿素、丙二醛、相对电导率及根系活力。结果表明,两种启动子对AtDREB2A表达的调控存在明显差异,35S启动子调控的AtDREB2A为超量表达,碱胁迫处理后显著上调,达57.6倍;rd29A启动子调控AtDREB2A诱导表达,表达量低于35S启动子调控株系(20.7倍),AtDREB2A超量表达抑制植株正常生长。在幼苗期和成苗期,两种启动子各转基因株系均有一定耐碱能力,但存在差异。AtDREB2A诱导表达耐碱性效果更明显,其叶绿素含量、相对电导率、MDA、根系活力变化均显著低于AtDREB2A超量表达。研究两种启动子调控的转AtDREB2A基因苜蓿耐碱效果,为AtDREB2A基因在苜蓿耐碱基因工程中应用提供方法。rd29A or CaMV-35S promoter is widely used in plant genetic engineering, but the effect of regulation is different in transgenic plants with different genes. Real-time PCR was used to assess different expression level of AtDREB2A gene in transgenic alfalfa lines regulated by rd29A and CaMV-35S promoters, respectively. For alkaline stress treatments, at the seedling stage plants were treated with 50 mmol. L1 NaHCO3 （pH 8.0） stress and in mixed alkali soil （pH 9.3）, then, the phenotype of the plants and the survival rate were observed, and physiological indicators including chlorophyll, relative conductivity, MDA and root activity were investigated, The results showed that an obvious difference in the regulation of geneexpression of AtDREB2A by rd29A and CaMV-35S promoters was observed. AtDREB2A gene was overexpressed under the regulation of CaMV-35S promoter, after alkaline stress treatment for 1 h, the expression of AtDREB2A gene increased significantly, increased by 57.6-fold. But the expression of AtDREB2A gene in the rd29A-lines was not as high as that of the lines with 35S-AtDRE.B2A gene （only 20.7-fold）. It was deduced that AtDREB2A gene overexpression inhibited the normal growth of transgenic alfalfa. Alkali stress resisitance of AtDREB2A gene induced expression was better than AtDREB2A gene overexpression in transgenic alfalfas. The reduction of chlorophyll content, relative conductivity, MDA and root activity in transgenic alfalfa with rd29A promoter were significantly less than that with CaMV-35S promoter. The aim of this study was to compare the alkaline tolerance of transgenic alfalfa with AtDREB2A （AB007791） gene regulated by different promoters, and to provide an effective method of application of alkali-stress genetic engineering with AtDREB2A genes in alfalfa.

关 键 词：苜蓿 AtDREB2A RD29A启动子 耐碱性 转基因 

分 类 号：S541.9[农业科学—作物学]