The RNA m6A Methyltransferase PvFIP37 Activates Vacuole Transport and Glutathione Detoxification Pathways to Increase Switchgrass Cd Tolerance.

Cadmium (Cd) pollution is a growing global issue that poses significant threats to ecosystems and human health. N6-methyladenosine (m6A) plays an essential role in regulating plant growth and stress responses, but the biological functions and regulatory mechanisms of m6A core enzymes under Cd stress remain largely unexplored. In this study, we demonstrate that PvFIP37 (WTAP human homologue protein) enhances Cd tolerance in switchgrass by activating PvYSL7, PvYSL17, PvABCC4 and PvABCC9 to transport Cd to the vacuoles. Additionally, PvFIP37 stabilises PvGST3 and PvGSTU6 within the glutathione S-transferase detoxification pathway, leading to increased GST activity and a higher GSH/GSSG ratio, thus alleviating oxidative damage in switchgrass under Cd stress. We have further shown that PvMTA interacts with PvFIP37 and targets the same set of genes as PvFIP37 to enhance switchgrass Cd tolerance. In summary, our study illustrates a novel mechanism of m6A methyltransferase-mediated Cd tolerance in switchgrass and provides valuable genetic resources for breeding Cd tolerant plants.