PUFA-PLs biosynthesis enzymes contribute to pathogenic development of rice blast fungus Magnaporthe oryzae

Rice blast is one of the most devastating diseases and a serious threat to global food security. It is caused by the ascomycetous fungus Magnaporthe oryzae. During the pathogenic development of M. oryzae, ferroptotic death of conidial cells is critical for appressorium formation and infection to host rice. In this study, we identified and functionally characterised orthologs of fatty acid desaturase (Fad2) and acyl-CoA synthetase long-chain family (Acsl4) in M. oryzae. Pathogenicity was impaired in the fad2Δ or acsl4Δ mutant and targeted lipidomics analysis demonstrated that Fad2 and Acsl4 were involved in the production of polyunsaturated fatty acids (PUFAs)-containing phospholipids (PUFA-PLs) potentially contributing to ferroptosis. Treatment with FeCl₃, an oxidative agent to cause lipid peroxidation, could partially restore fad2Δ pathogenicity. Fad2 was also found to potentially interact with proteins involved in cellular redox homoeostasis. Overall, our results elucidate the role of PUFA-PLs biosynthesis in fungal cell death and fungal pathogenicity, providing a theoretical basis for the development of specific pesticides/drugs targeting ferroptosis caused by lipid peroxidation.