Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, XueYuan Rd 4, Longhua District, Haikou, Hainan, People's Republic of China 571101.
Appl Biochem Biotechnol. 2013 Mar;169(5):1557-65. doi: 10.1007/s12010-012-0071-4. Epub 2013 Jan 16.
AtNUDT5 is a cytosol Nudix that catalyzes the hydrolysis of a variety of substrates. In this report, a 1,387-bp 5'-flanking region of the AtNUDT5 gene was isolated from Arabidopsis thaliana. The tissue-specific activity of the 5'-flanking region was investigated by using the GUS gene as a reporter in transgenic A. thaliana plants. Weak GUS activity appeared in vascular tissues of young plants, strong GUS activity appeared in the axial roots, but no GUS activity was observed in the root cap, lateral roots, rosette leaf, mature silique and reproductive tissues such as stamen, pistil, and petal. Furthermore, by using these transgenic A. thaliana plants, results of the histochemical staining and fluorometric assays of GUS activity showed that the AtNUDT5 promoter can be activated by both avirulent Pst avrRpm1 and virulent Pst strains at 5 h post-infiltration and that the activity of AtNUDT5 promoter increased significantly at 24 h post-infiltration. Taken together, our results demonstrated that the AtNUDT5 promoter is pathogen-responsive. The promoter may be used to develop transgenic plants with an increased tolerance to pathogenic stresses.
AtNUDT5 是一种细胞质 Nudix，可催化多种底物的水解。本研究从拟南芥中分离得到了 AtNUDT5 基因的 1387bp5'-侧翼区。通过将 GUS 基因作为报告基因在转基因拟南芥植株中进行研究，分析了该侧翼区的组织特异性活性。在幼苗的维管组织中观察到微弱的 GUS 活性，在主根中观察到强烈的 GUS 活性，但在根冠、侧根、莲座叶、成熟的蒴果以及雄蕊、雌蕊和花瓣等生殖组织中未观察到 GUS 活性。此外，通过使用这些转基因拟南芥植物，对 GUS 活性的组织化学染色和荧光测定结果表明，AtNUDT5 启动子可被无毒 Pst avrRpm1 和有毒 Pst 菌株在侵染后 5 小时激活，并且在侵染后 24 小时，AtNUDT5 启动子的活性显著增加。综上所述，我们的研究结果表明，AtNUDT5 启动子是对病原体有响应的。该启动子可用于开发对致病胁迫具有更高耐受性的转基因植物。
