Colobanthus quitensis, trascriptome assembly (roots and leaves) exposed to Persistent Organic Pollutants (POPs)

Antarctica is one of the most sensitive ecosystems to the negative effects of Persistent Organic Pollutants (POPs) on biodiversity due to lower temperatures, that promote their accumulation or even biomagnification; however, the impact on vascular plants is unknown. Moreover, fungal symbionts could modulate the effects on host plants to cope with this stress factor. This study investigates the molecular and ecophysiological responses of the Antarctic plant <i>Colobanthus quitensis</i> to POPs in different populations along a latitudinal gradient, emphasizing the role of endophytic fungi. The results show that <i>C. quitensis</i> in association with fungal endophytes induced lower lipid peroxidation, higher proline content and higher photosynthetic capacity, as well as higher biomass and survival percentage. On the other hand, endophytic fungi play a crucial role in modulating the response of the Antarctic population of <i>C. quitensis</i> at 67°S, significantly contributing to its overall functional adaptation. Transcriptomics analyses reveal how endophytes enhance the tolerance of <i>C. quitensis</i> to POPs. Our findings indicate significant gene expression changes related to stress response and detoxification, underscoring endophytes' contribution to plant resilience under environmental stress, particularly in extreme conditions like Antarctica. The implications of these findings are relevant for the biosecurity of one of the last pristine bastions worldwide.