N terminus and C terminus of Arabidopsis P4-ATPase AtALA1 facilitate the detoxification of the mycotoxin deoxynivalenol in wheat

Fusarium head blight (FHB) is a devastating disease affecting many important cereal crops. The disease is mainly caused by Fusarium graminearum, which produces mycotoxins, e.g., deoxynivalenol (DON), that contaminate grains, leading to serious issues in food safety worldwide. Here, we demonstrate that expressing the Arabidopsis P4-ATPase flippase gene, AtALA1, significantly increases wheat resistance to FHB, while substantially reducing DON content in grains. However, expressing TaALA1s, the wheat homologs of AtALA1, does not enhance the resistance. We discovered that the N terminus and C terminus of AtALA1 are crucial for its role in DON detoxification. The motif [DE]_nX_1-2FXX[FL]XXXR, found exclusively in the N terminus of ALA1s in Brassicaceae species, facilitates AtALA1-associated vesicle transport by binding with AP-2. Meanwhile the DON-stimulated phosphorylation at three key sites in the C terminus is responsible for promoting DON trafficking into vacuoles. Our findings suggest a great potential for vesicle-associated detoxification in FHB resistance and food safety.