Abstract:Plant E3 ubiquitin ligase plays an important role against abiotic stresses such as high salt and drought. In this study, we isolated soybean E3 ubiquitin ligase gene GmAIRP1, which contained a full length coding sequence of 642 bp, encoding for 213 amino acids. Protein domain analysis indicated that GmAIRP1 carried a typical RING-finger domain. By phylogenetic tree analysis, GmAIRP1 was found to be closely related with MtAIRP1. The expression of GmAIRP1 turned to be elevated under salt, drought or ABA stresses, particularly at 1h or 3h post treatments. By transforming GmAIRP1 into tobacco, the transgenic tobacco grew better than the wild type after 21 days of high salt and drought stress, implying an elevated stress tolerance. Furthermore, we analyzed the physiological indicators, including POD and CAT activities that were elevated in transgenic plants than that of the control, and the MDA content that was constantly lower in transgenic plants. Taken together, these results indicated that GmAIRP1 acts as a positive regulator in plant responding to high salt and drought stress, possibly by activating antioxidant enzyme activity and increasing accumulation of osmotic adjustment substances.