DIFFERENTIAL EFFECTS OF REACTIVE OXYGEN SPECIES ON AUTOPHAGY IN ARABIDOPSIS

Abstract

ABSTRACTAutophagy plays a key role in the responses to different stress condition in plants. Reactive oxygen species (ROS) are common modulators of stress responses, having both toxic and signaling functions. In this context, the relationship between ROS and autophagy regulation remains unclear, and in some aspects, contradictory. In this study, we employed pharmacological and genetic approaches to investigate the effects of different ROS on the cytoplastic redox state and autophagic flux inArabidopsis thaliana. Ours results demonstrated that oxidative treatments with H2O2and MV, which drastically increased the oxidized state of the cytoplasm, reduced the autophagic flux. Conversely, singlet oxygen, which did not have significant effects on the cytoplasmic redox state, increased the autophagic flux. Additionally, our findings indicated that after H2O2and high light treatments and during the recovery period, the cytoplasm returned to its reduced state, while autophagy was markedly induced. In summary, our study unveils the differential effects of ROS on the autophagic flux, establishing a correlation with the redox state of the cytoplasm. Moreover, it emphasizes the dynamic nature of autophagy in response to oxidative stress and the subsequent recovery period.HIGHLIGHTThis research shows the differential effects of reactive oxygen species on autophagic flux, highlighting their impact on the cytoplasmic redox state.