Sphinganine C4-Hydroxylase MoSur2 Regulates Lipid Homeostasis and Cell Development in Magnaporthe oryzae

Magnaporthe oryzae causes rice blast disease and possesses significant threat to global rice production. Recent investigations revealed the importance of sphingolipids in various cellular processes, yet the pathological role and characterization involved in virulence in M. oryzae remain poorly understood. In this study, we investigated a key sphinganine C4-hydroxylase in MoSur2 and its impact on conidial development and pathogenicity. MoSur2 is localized in the endoplasmic reticulum and interacts with upstream proteins MoSpt2 and MoTsc10. Knockout of MoSur2 resulted in significant reduction in plasma membrane tension and virulence on the host plant. In addition, MoSur2 also regulates cell wall intensity, osmotic stress pathway, and responses to the target of rapamycin complex 2 signaling. Lipidomics analysis further revealed significant alterations in membrane components, resulting in MoSUR2 deletion mutant. These findings improve our understanding of MoSur2 that could be useful for controlling rice blast disease.