Proteomics and Lysine Acetylation Modification Reveal the Responses of Pakchoi (Brassica rapa L. ssp. chinensis) to Oxybenzone Stress

The broad-spectrum UV filter oxybenzone is toxic to plantsat environmentallyrelevant concentrations. Lysine acetylation (LysAc) is one of theessential post-translational modifications (PTMs) in plant signalingresponses. The goal of this study was to uncover the LysAc regulatorymechanism in response to toxic exposures to oxybenzone as a firststep in elucidating xenobiotic acclimatory reactions by using themodel Brassica rapa L. ssp. chinensis. A total of 6124 sites on 2497 proteins were acetylated,63 proteins were differentially abundant, and 162 proteins were differentiallyacetylated under oxybenzone treatment. Bioinformatics analysis showedthat a large number of antioxidant proteins were significantly acetylatedunder oxybenzone treatment, implying that LysAc alleviated the adverseeffects of reactive oxygen species (ROS) by inducing antioxidant systemsand stress-related proteins; the significant changes in acetylationmodification of enzymes involved in different branches of carbon metabolismin plants under oxybenzone treatment mean that plants can change thedirection of carbon flow allocation by regulating the activities ofcarbon metabolism-related enzymes. Our results profile the proteinLysAc under oxybenzone treatment and propose an adaptive mechanismat the post-translational level of vascular plants in response topollutants, providing a dataset reference for future related research.