Fusarium graminearum is the main pathogenic fungus causing Fusarium head blight (FHB), which is a wheat disease with a worldwide prevalence. In eukaryotes, phosphatidylinositol 4-phosphate (PI4P), which participates in many physiological processes, is located primarily in different organelles, including the trans-Golgi network (TGN), plasma membrane and endosomes. Type II phosphatidylinositol 4-kinases (PI4Ks) are involved in regulating the production of PI4P in yeast, plants and mammalian cells. However, the role of these proteins in phytopathogenic fungi is not well understood. In this study, we characterized the type II PI4K protein FgLsb6 in F. graminearum, a homolog of Lsb6 in Saccharomyces cerevisiae. Unlike Lsb6, FgLsb6 localizes to the vacuoles and endosomes. The ΔFglsb6 mutant displayed defects in vegetative growth, deoxynivalenol (DON) production and pathogenicity. Furthermore, the ΔFglsb6 deletion mutant also exhibited increased resistance to osmotic, oxidative and cell wall stresses. Further analyses of the ΔFglsb6 mutant showed that it was defective in the generation of PI4P on endosomes and endocytosis. Collectively, our data suggest that the decreased vegetative growth and pathogenicity of ΔFglsb6 was due to the conservative roles of FgLsb6 in the generation of PI4P on endosomes and endocytosis.

禾谷镰刀菌是引起镰刀菌枯萎病（FHB）的主要病原真菌，这是一种在世界范围内流行的小麦病害。在真核生物中，参与许多生理过程的 4-磷酸磷脂酰肌醇 (PI4P) 主要位于不同的细胞器中，包括反式高尔基网络 (TGN)、质膜和内体。II 型磷脂酰肌醇 4-激酶 (PI4K) 参与调节酵母、植物和哺乳动物细胞中 PI4P 的产生。然而，这些蛋白质在植物病原真菌中的作用尚不清楚。在这项研究中，我们表征了F 中的II 型 PI4K 蛋白 FgLsb6 。graminearum , Saccharomyces cerevisiae中 Lsb6 的同源物. 与 Lsb6 不同，FgLsb6 定位于液泡和内体。Δ Fglsb6突变体在营养生长、脱氧雪腐镰刀菌烯醇 (DON) 产生和致病性方面表现出缺陷。此外，Δ Fglsb6缺失突变体还表现出对渗透、氧化和细胞壁应激的抵抗力增加。对 Δ Fglsb6突变体的进一步分析表明，它在内体和内吞作用上产生 PI4P 有缺陷。总的来说，我们的数据表明 Δ Fglsb6 的营养生长和致病性降低是由于 FgLsb6 在内体和内吞作用上产生 PI4P 中的保守作用。