Mechanical stress induces molecular changes in oolong tea: Insights from multi-omics analysis

1. Integrated multi-omics (metabolomics, transcriptomics, proteomics) elucidates tea leaf responses to mechanical stress. 2. Mechanical stress-activated DAMPs ignite the Ca² + –JA–GSH signaling cascade, orchestrating downstream aroma biosynthesis. 3. Mechanical stress induces LOX / PAR genes and their encoded proteins in α -linolenic/Phe metabolism, boosting accumulation of 2-phenylethanol and jasmine lactone. Understanding the molecular responses of tea leaves to mechanical stress is crucial for elucidating the mechanisms of post-harvest quality formation during oolong tea processing. This study emplemented an integrated multi-omics strategy to characterize the changes and interactions among metabolomic (MB), transcriptomic (TX), and proteomic (PT) profiles in mechanically stressed tea leaves. Mechanical stress initially activated damage-associated molecular patterns (DAMPs), including Ca 2+ signaling, jasmonic acid signaling, and glutathione metabolism pathways. These processes subsequently induced quality-related metabolic pathways (QRMPs), particularly α -linolenic acid and phenylalanine metabolism. Up-regulated expression of LOX , ADH1 , and PAR genes, together with the increased abundance of their encoded proteins, respectively promoted the accumulation of jasmine lactone, benzyl alcohol, and 2-phenylethanol. These findings indicate that mechanical stress influence the metabolite biosynthesis in tea leaves through coordinated molecular responses. This study provides new insights into the molecular mechanisms underlying tea leaf responses to mechanical stress and a foundation for future investigations into how early molecular events may contribute to post-harvest metabolic changes during oolong tea processing.