OsJAZ5 promotes salt tolerance in rice and physical interactions with OsMYL1 and OsMYL2 stimulate jasmonic acid signaling

Abstract

Abstract Salt stress is one of the main abiotic stresses that affect plants. The jasmonic acid (JA) signaling pathway is an important pathway that converts the normal growth state into the stress state when plant cells encounter abiotic stress. OsJAZ5 is a JAZ protein family gene, but how the JA signaling pathway promotes rice responses to salt stress is unclear. In this study, after screening for the OsJAZ5 gene, a yeast function analysis using the yeast mutant Axt3k was performed to determine its salt resistance sensitivity. The phenotype analysis showed that it was overexpressed in rice and promoted growth under salt stress. An analysis of the superoxide dismutase, peroxidase, phenylalanine ammonolyase, and catalase activities showed that the OE-3 and OE-5 lines promoted OsJAZ5 activity to maintain the reactive oxygen species dynamic balance under salt stress. In addition, the protein-protein interaction analysis and protein-protein docking confirmed that OsJAZ5 interacts with OsMYL1 and OsMYL2, demonstrated that OsJAZ5 promotes reactions by OsMYL1, OsMYL2, and OsMYC2 and that their expressions were further enhanced by OsJAZ5 through JA signaling of OsMYC2. Thus, expression of the JA signaling response gene was activated by salt stress and its effect on OsJAZ5 promoted salt tolerance in rice.