ABSTRACT

In this study, transgenic Arabidopsis lines expressing a potato gene (D43), encoding Glyceraldehyde 3-phosphate dehydrogenase, were studied. The D43 plants exhibited improved morphological parameters and accumulation of photosynthetic pigments compared to wild-type (WT) plants under salinity stress conditions. In addition, the D43 transgenic plants showed significantly reduced electrolyte leakage, higher stomatal conductance, lower malondialdehyde (MDA) content, and higher proline content than the WT plants under salinity stress. The gene expression analysis showed that the D43 plants accumulated 1.7-fold, 2.2-fold, and 1.3-fold higher mRNA transcripts of genes encoding the antioxidant enzymes ascorbate peroxidase (APX), superoxide dismutase (SOD), and catalase (CAT), respectively under salt-stress conditions. Furthermore, they significantly altered the expression of seven major stress-responsive genes, which indicated that overexpression of the potato D43 gene gave salinity stress resistance to Arabidopsis. Chlorophyll-a fluorescence kinetics confirmed the efficient photon absorption, electron transport, and overall PSII efficiency that led to improved photosynthesis in the D43 plants subjected to NaCl-induced salinity stress. Overall, our findings have suggested that potato D43 is a potential candidate gene for developing salinity stress resistance in higher plants.

摘要

在这项研究中，转基因拟南芥系表达马铃薯基因（D43)，编码甘油醛 3-磷酸脱氢酶，进行了研究。与盐胁迫条件下的野生型 (WT) 植物相比，D43 植物表现出改善的形态参数和光合色素的积累。此外，与盐胁迫下的 WT 植物相比，D43 转基因植物显示出显着减少的电解质泄漏、更高的气孔导度、更低的丙二醛 (MDA) 含量和更高的脯氨酸含量。基因表达分析表明，D43 植物积累的抗坏血酸过氧化物酶 (APX)、超氧化物歧化酶 (SOD) 和过氧化氢酶 (CAT) 编码抗氧化酶基因的 mRNA 转录物分别高出 1.7 倍、2.2 倍和 1.3 倍在盐胁迫条件下。此外，他们显着改变了七个主要应激反应基因的表达，拟南芥。叶绿素-a 荧光动力学证实了有效的光子吸收、电子传输和整体 PSII 效率，从而改善了受到 NaCl 诱导的盐度胁迫的 D43 植物的光合作用。总的来说，我们的研究结果表明，马铃薯 D43 是在高等植物中发展盐胁迫抗性的潜在候选基因。