Dynamic transcriptomic and metabolomic responses of rice under high light stress

High light (HL) stress poses a major challenge to crop productivity by diminishing photosynthetic efficiency, yet its dynamic regulatory mechanisms in rice remain insufficiently understood. Through integrated time-course transcriptomic and metabolomic analyses, we showed that HL exposure induces rapid, multi-layered responses in rice seedlings within hours. HL rapidly and persistently inhibited photosynthetic capacity, concomitantly with the suppression of the gene expression associated with photosynthetic processes significantly enriched among core differentially expressed genes. Co-expression network analysis highlighted key transcription factors mediating HL acclimation and photosynthetic repression. Metabolomic profiling uncovered immediate lipid remodeling and sustained accumulation of photosynthetic intermediates, indicating metabolic bottlenecks in carbon fixation. As an oxylipin derivative, phytohormone jasmonic acid (JA) is rapidly induced by HL and JA signaling is significantly regulated under HL conditions. Hormonal pathways were also dynamically reprogrammed. This research provides valuable insights into the physiological, transcriptional, and metabolic mechanisms that enable rice to adapt to HL stress, contributing to strategies for enhancing crop resilience in challenging light environments.