Wang_2022_J.Integr.Agric__

Drought and salt stresses, as major environmental abiotic stresses in agriculture worldwide, affect plant growth and crop productivity and quality. The development of crops with higher drought and salt tolerance is therefore highly desirable. Here, we reported the isolation and biological function and molecular characterization of a novel maspardin gene OsMas1 from rice. The OsMas1 protein was localized to the cytoplasm. The expression levels of OsMas1 were up-regulated under mannitol, PEG6000, NaCl and ABA treatments in rice. The OsMas1 gene was introduced into rice cultivar Zhonghua 11 (wild-type, WT) and OsMas1-overexpression (OsMas1-OE) plants exhibited significantly enhanced salt and drought tolerance, while OsMas1-interference (OsMas1-RNAi) plants exhibited decreased tolerance to salt and drought stresses, compared with WT. OsMas1-OE plants exhibited enhanced hypersensitive, while OsMas1-RNAi plants showed less sensitive to exogenous ABA treatment at both germination and post-germination stages. ABA, proline and K+ content and superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and photosynthesis activities were significantly increased, while malonaldehyde (MDA), hydrogen peroxide (H2O2), superoxide anion radical (O2-) and Na+ content were significantly decreased in OsMas1-OE plants compared with OsMas1-RNAi and WT plants. Overexpression of OsMas1 up-regulated the genes involved in ABA signaling, proline biosynthesis, ROS-scavenging system, photosynthesis and ion transport under salt and drought stresses. Collectively, our results indicate that OsMas1 gene functions in improving salt and drought tolerance in rice, which may serve as a candidate gene for enhancing the resistance to abiotic stresses in crops.