Anatase TiO Nanoparticles Induce Autophagy and Chloroplast Degradation in Thale Cress ().

The extensive use of TiO nanoparticles and their subsequent release into the environment have posed an important question about the effects of this nanomaterial on ecosystems. Here, we analyzed the link between the damaging effects of reactive oxygen species generated by TiO nanoparticles and autophagy, a housekeeping mechanism that removes damaged cellular constituents. We show that TiO nanoparticles induce autophagy in the plant model system and that autophagy is an important mechanism for managing TiO nanoparticle-induced oxidative stress. Additionally, we find that TiO nanoparticles induce oxidative stress predominantly in chloroplasts and that this chloroplastic stress is mitigated by autophagy. Collectively, our results suggest that photosynthetic organisms are particularly susceptible to TiO nanoparticle toxicity.