SUMMARY Cold stress is a major abiotic stress that threatens rice productivity and global food security. Elucidating the complex mechanisms of cold tolerance in rice is crucial for developing cold‐tolerant varieties through molecular breeding. Here, we identified a WRKY transcription factor, OsWRKY11 , as a positive regulator of cold tolerance in rice. OsWRKY11 expression was induced by both cold stress and exogenous jasmonic acid (JA) treatment. Genetic evidence showed that OsWRKY11 overexpression enhanced cold tolerance of rice seedlings, while knockout of OsWRKY11 reduced cold tolerance. In addition, we demonstrated that under cold stress, OsWRKY11 directly activates both the JA biosynthesis gene OsLOX1 and the CBF family members ( OsDREB1A , OsDREB1B , and OsDREB1F ) by binding to W‐box motifs in their promoters. Physiological analyses showed that OsWRKY11 promotes JA biosynthesis and enhances reactive oxygen species (ROS) scavenging under cold stress. This elevated JA level, in turn, upregulates OsWRKY11 expression and thereby creates a positive feedback loop that amplifies cold stress signaling. Furthermore, cold stress assays with MeJA and JA synthesis inhibitor ibuprofen suggested that OsWRKY11 functions in the JA‐mediated cold signaling pathway. Finally, biochemical analyses demonstrated that OsICE1 physically interacts with OsWRKY11, forming a synergistic complex that enhances the transcriptional activation and DNA‐binding ability of OsWRKY11. Taken together, our results strongly suggest that the OsWRKY11–OsICE1 module orchestrates cold tolerance in rice by integrating ROS accumulation with the JA and CBF signaling pathways. This regulatory module provides promising targets for the molecular breeding of cold‐tolerant rice varieties.
Wan et al. (Wed,) studied this question.