Overexpression of EuSIP5 gene to improve drought resistance in tobacco

Abstract In order to study the drought resistance of the Eucommia ulmoides soluble inorganic pyrophosphatase 5 (EuSIP5) gene, the cDNA sequence of the EuSIP5 gene was amplified from Eucommia ulmoides Oliver (E. ulmoides) by RT-PCR. Bioinformatic analysis indicated that EuSIP5 might be an unstable amphipathic protein, mainly located in the plasma and nuclear membranes. E. ulmoides, the highest expression of the EuSIP5 gene was found in male leaves and pericarp from April to October, and in leaves of E. ulmoides in July and September. During drought, the expression of EuSIP5 in seedling E. ulmoides leaves was significantly higher than that of the control. An overexpression vector harboring the EuSIP5 was constructed and introduced into the tobacco (Nicotiana tabacum cv. Xanthi). We found that during drought stress, the appearance of wilting was delayed by 4 days in transgenic tobacco plants (OE) compared with wild type plants (WT), and the expression of drought-related genes DET2, CYP85A1, P5CS, ERF1 and F-box was found to be increased in transgenic tobacco leaves, as well as the enzyme activities of the protective enzymes: peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) were significantly higher than those of the WT, and the malondialdehyde (MDA) content was lower than the WT. These results indicated that the introduction of EuSIP5 gene into tobacco increased the expression of drought-related genes, enhanced the anti-membrane oxidation ability of tobacco, and reduced the oxidative stress damage, thus improving the drought resistance of tobacco.