Characterization of two MFS transporters involved in infection-related development and pathogenicity of the rice blast fungus

The Major Facilitator Superfamily (MFS) is an extensive group that plays important roles in nutrient and metabolite transport, drug resistance, and nerve signaling. To explore the potential roles of MFS transporters in Magnaporthe oryzae , we identified and characterized two MFS transporters, MoMfs1 and MoMfs3, from the rice blast fungus M. oryzae . Targeted gene disruption revealed that both transporters are involved in fungal development and the efflux of fungicides. Moreover, the MoMFS1 and MoMFS3 mutants exhibited decreased extracellular peroxidase and laccase activities, likely due to reduced production or secretion of these enzymes. Interestingly, the ∆ Momfs3 mutant showed reduced pathogenicity and limited expansion of invasive hyphae, indicating that MoMfs3 plays a critical role in pathogenicity. Metabolic analysis identified 537 down-regulated metabolites and 17 specific compounds, including toxins, antibacterial substances, and biotin, suggesting that MoMfs3 is involved in the secretion of secondary metabolites. In summary, our findings illustrate that MFS transporters are important for the development of M. oryzae throughout the disease cycle by selectively modulating specific transporters.