Aryl hydrocarbon receptor (AhR)-mediated reporter gene expression systems in transgenic tobacco plants
Aryl hydrocarbon receptor (AhR)-mediated reporter gene expression systems in transgenic tobacco plants
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DOI：
10.1007/s00425-007-0592-1
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发表时间：
2007-12-01
期刊：
影响因子：
4.3
通讯作者：
Ohkawa, Hideo
中科院分区：
文献类型：
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作者：
Kodama, Stisumu;Okada, Kumiko;Ohkawa, Hideo
在哺乳动物中，芳烃受体（AhR）介导某些基因的表达，包括CYP1A1，以应对暴露于二恶英和相关化合物。我们在转基因烟草植物中构建了由AhR、AhR核转位子（Arnt）和外源反应元件（XRE）驱动启动子组成的β -葡糖醛酸酶（GUS）报告基因的AhR介导的小鼠基因表达系统。在AhR配体3-甲基胆蒽（MC）、β -萘黄酮（β NF）和靛蓝处理下，转基因烟草表现出增强的GUS活性，可能是通过诱导报告基因的表达。重组AhR （AhRV）激活结构域被单纯疱疹病毒蛋白VP16取代，在转基因烟草植株中诱导GUS活性明显高于野生型AhR。携带AhRV的植物在MC处理下表达GUS报告基因呈剂量和时间依赖性；在固体培养基5 nM和25 μ M培养基浸泡12 h检测GUS活性，组织化学GUS染色表明该体系主要在叶和茎中有活性。这些结果表明，ahr介导的报告基因表达系统具有在环境中进行二恶英生物检测的潜力，并可作为一种新的植物二恶英基因表达系统。
In mammals, the aryl hydrocarbon receptor (AhR) mediates expression of certain genes, including CYP1A1, in response to exposure to dioxins and related compounds. We have constructed a mouse AhR-mediated gene expression systems for a beta-glucuronidase (GUS) reporter gene consisting of an AhR, an AhR nuclear translocator (Arnt), and a xenobiotic response element (XRE)-driven promoter in transgenic tobacco plants. On treatment with the AhR ligands 3-methyl-cholanthrene (MC), beta-naphthoflavone (beta NF), and indigo, the transgenic tobacco plants exhibited enhanced GUS activity, presumably by inducible expression of the reporter gene. The recombinant AhR (AhRV), with the activation domain replaced by that of the Herpes simplex virus protein VP16, induced GUS activity much more than the wild-type AhR in the transgenic tobacco plants. Plants carrying AhRV expressed the GUS reporter gene in a dose- and time-dependent manner when treated with MC; GUS activity was detected at 5 nM MC on solid medium and at 12 h after soaking in 25 mu M MC. Histochemical GUS staining showed that this system was active mainly in leaf and stem. These results suggest that the AhR-mediated reporter gene expression system has potential for the bioassay of dioxins in the environment and as a novel gene expression system in plants.