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胡杨(Populus euphratica Oliv.)具有极强抗盐碱能力。本实验室前期胡杨微阵列芯片数据结果显示:盐胁迫下,胡杨谷胱甘肽过氧化物酶基因(PeGPX)的转录上调,暗示该基因可能对胡杨耐盐性具有一定的作用。为分析 GPX 对植物耐盐性的贡献,本研究以胡杨为材料,利用 RT-PCR 方法克隆了胡杨谷胱甘肽过氧化物酶PeGPX基因,并在烟草中过量表达该基因,以分析谷胱甘肽过氧化物酶活性与植物耐盐性的关系。研究结果显示,实验中克隆的 cDNA (PeGPX)编码谷胱甘肽过氧化物酶,其 ORF 为 693 bp,其蛋白由 231 个氨基酸编码。过量表达 PeGPX 基因的烟草与野生型烟草的耐盐性实验结果显示,野生型烟草植株在加 NaCl(200 mmol/L)的 MS 培养基中生长 15 d 后,无明显的长高,且不长根;而转基因烟草在同样的加盐培养基上,生长基本没有受到抑制,植株生长状态良好,并且能够长根。光合数据显示,在盐胁迫下过量表达 PeGPX 基因烟草的净光合速率受到影响明显小于野生型烟草的净光合速率。酶活数据显示,转基因株系 GPX 酶活与野生型的相比在盐胁迫下活性有非常显著的提高。我们的研究结果说明:过表达 PeGPX 基因使得烟草的耐盐性得到显著提高,这对深入研究PeGPX基因在胡杨耐盐机制中的作用具有重要的意义。高,这对深入研究PeGPX基因在胡杨耐盐机制中的作用具有重要的意义。
Populus euphratica Oliv. Has a strong resistance to salt and alkali. The data of Populus euphratica microarray in our laboratory showed that under salt stress, the up-regulation of glutathione peroxidase (PeGPX) gene expression in Populus euphratica suggested that this gene may play a role in the salt tolerance of Populus euphratica. In order to analyze the contribution of GPX to the salt tolerance of plants, we used Populus euphratica as material and cloned the Populus euphratica glutathione peroxidase PeGPX gene by RT-PCR, and overexpressed this gene in tobacco to analyze the effects of glutathione Relationship Between Glycopeptide Peroxidase Activity and Salt Tolerance in Plants. The results showed that the cloned cDNA (PeGPX) encoded glutathione peroxidase, whose ORF was 693 bp and its protein was encoded by 231 amino acids. The results of salt tolerance experiments showed that the wild-type tobacco plants grown in MS medium supplemented with NaCl (200 mmol / L) for 15 days showed no obvious growth and no longer While the transgenic tobacco had basically no growth inhibition on the same salt-added medium, the plants grew well and could grow roots. Photosynthetic data showed that net photosynthetic rate of PeGPX-overexpressing tobacco under salt stress was significantly lower than that of wild-type tobacco. The enzyme activity data showed that the GPX activity of the transgenic lines showed a very significant increase in activity under salt stress compared with the wild type. Our results indicate that overexpression of PeGPX gene leads to a significant increase in the salt tolerance of tobacco, which is of great significance for further study on the role of PeGPX in salt-tolerant mechanism of Populus euphratica. High, which is of great significance for further studying the role of PeGPX gene in the salt tolerance mechanism of Populus euphratica.