Overexpressing the WRKY transcription factor OsWRKY97 improves drought tolerance in rice

Background: WRKY transcription factor (TF) is one of the largest TF families in plants and plays an important role in plant development and stress protection. However, the function of individual WRKY gene in plants are still under investigation. Here, we identified a new member of WRKY TF family, OsWRKY97 , and analyze its role in stress resistance by using a series of transgenic plant lines. Results: OsWRKY97 , which positively regulates drought tolerance in rice. OsWRKY97 was expressed in all examined tissues and could be induced by various abiotic stresses. OsWRKY97 is located in the nucleus. Compared with the wild-type (WT), OsWRKY97 -overexpressing (OE) plants enhanced the tolerance of rice to drought and osmotic stress. In addition, OE plants also showed higher sensitivity to exogenous abscisic acid (ABA). When exposed to drought stress, up-regulation OsWRKY97 increased the accumulation of ABA and reduced water loss. Furthermore, OE plants achieved higher proline content and reduced levels of malondialdehyde (MDA) and reactive oxygen species (ROS). The homeostasis of ROS was maintained via the activity of active oxygen scavenging enzyme, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), activated by OsWRKY97Conclusions: These results indicate that OsWRKY97 plays a crucial role in the response to drought stress and may possess high potential value in improving drought tolerance in rice.