【摘要】 为研究棉花NAC转录因子基因GhSNAC3启动子的结构和功能,以鲁棉研32号基因组为模板,用PCR扩增的方法得到棉花基因GhSNAC3的启动子序列,利用分析网站PlantCARE、PLACER和BDGP对启动子上存在的顺式作用元件进行了预测与分析,在此基础上利用该启动子及GhSNAC3基因构建植物表达载体,并通过烟草遗传转化进一步研究启动子的转录活性。结果表明GhSNAC3启动子除含有CAAT-box等基本顺式作用元件外,还含有茉莉酸、赤霉素和脱落酸响应元件以及大量光顺式作用元件和逆境胁迫诱导相关的顺式调控元件。采用不同胁迫处理转基因烟草并进行表达分析,结果显示GhSNAC3在盐胁迫下植株根部有高水平的表达,而在茎和叶中表达量极低,表明GhSNAC3在逆境胁迫应答过程中可能具有重要功能,其启动子是一个盐诱导型启动子,具有组织特异性。研究结果为棉花NAC信号通路研究和耐盐基因工程改良提供了理论依据。更多还原

【Abstract】 In order to analyze the structure and function of the promoter of cotton NAC transcription factor gene GhSNAC3,the promoter fragment was cloned and identified from Lumianyan 32 in Gossypium hirsutum L.. The cisacting elements in the promoter sequence was predicted and analyzed by using the online database of Plant CARE,PLACER and BDGP. A plant expression vector consisting of GhSNAC3 and its promoter was constructed and transformed into Nicotiana tabacum L. to investigate the transcription activities of the promoter under different stress treatments. The results showed that besides the basic cis-acting elements such as CAAT-box,there existed several Me JA,GA and ABA-responsive elements as well as multiple light-responsive elements and stress-induced controlling elements in the promoter. Under salt stress GhSNAC3 had a high level of expression in the roots of transgenic tobacco plants,while the expression level was low in the stems and leaves,suggesting that the gene GhSNAC3 might played an important role in stress responses in cotton,and its promoter might be tissue-specific and salt-inducible.The results provide the basis for the further study of cotton NAC signal pathway as well as salt tolerance improvement through genetic engineering in the future.更多还原