Background

Tobacco is an important economic crop, but the quality and yield have been severely impaired by bacterial wilt disease (BWD) caused by Ralstonia solanacearum.

Methods and results

Here, we describe a transgenic approach to prevent BWD in tobacco plants. A new root-specific promoter of an NtR12 gene was successfully cloned. The NtR12 promoter drove GUS reporter gene expression to a high level in roots but to less extent in stems, and no significant expression was detected in leaves. The Ribosome-inactivating proteins (RIP) gene from Momordica charantia was also cloned, and its ability to inhibit Ralstonia solanacearum was evaluated using RIP protein produced by the prokaryotic expression system. The RIP gene was constructed downstream of the NtR12 promoter and transformed into the tobacco cultivar “Cuibi No. 1” (CB-1), resulting in many descendants. The resistance against BWD was significantly improved in transgenic tobacco lines expressing NtR12::RIP.

Conclusion

This study confirms that the RIP gene confers resistance to BWD and the NtR12 as a new promoter for its specific expression in root and stem. Our findings pave a novel avenue for transgenic engineering to prevent the harmful impact of diseases and pests in roots and stems.

中文翻译：

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基于根特异性 NtR12 启动子的 RIP 表达增强了烟草对青枯病的抗性

 背景

烟草是重要的经济作物，但青枯菌引起的青枯病严重损害了烟草的品质和产量。

 方法和结果

在这里，我们描述了一种预防烟草植物 BWD 的转基因方法。成功克隆了NtR12基因的新根特异性启动子。 NtR12启动子驱动GUS报告基因在根中表达到高水平，但在茎中表达程度较低，并且在叶子中没有检测到显着的表达。还克隆了苦瓜核糖体失活蛋白（ RIP ）基因，并利用原核表达系统产生的RIP蛋白评估了其抑制青枯菌的能力。将RIP基因构建在NtR12启动子下游，并转化到烟草品种“翠碧1号”（CB-1）中，产生了许多后代。在表达NtR12::RIP 的转基因烟草品系中，对 BWD 的抗性显着提高。

 结论

这项研究证实RIP基因赋予BWD抗性，并且NtR12作为新的启动子在根和茎中特异性表达。我们的研究结果为转基因工程预防根部和茎部疾病和害虫的有害影响铺平了一条新途径。