Phosphatidylserine decarboxylases (Psds) are enzymes regulating phosphatidylethanolamine biosynthesis in prokaryotes and eukaryotes, and have the central role in lipid metabolism. To date, the functions of Psds in plant pathogenic fungi are not fully understood. In this study, we have characterized two yeast Psd orthologues: FgPsd1 and FgPsd2, in Fusarium graminearum. Our results indicate that FgPsd1 and FgPsd2 are localized in mitochondria and Golgi, respectively. In addition, we have determined that FgPsd1 is a lethal gene and deletion of FgPsd2 resulted in a significant reduction of mycelial growth and conidiation. Futhermore, the FgPsd2 deletion mutant (ΔFgPsd2) is defective in ascospore production and virulence in wheat. Our study has also found that the ΔFgPsd2 mutant is more sensitive to osmotic and oxygen stresses. Moreover, deletion of FgPsd2 reduced the formation of lipid droplets and aggravated autophagy in F. graminearum. In summary, our findings indicate that FgPsd2 is important for mycelial growth, sexual and asexual reproduction, virulence, lipid droplet formation and autophagy in F. graminearum.

磷脂酰丝氨酸脱羧酶 (Psds) 是调节原核生物和真核生物中磷脂酰乙醇胺生物合成的酶，在脂质代谢中起核心作用。迄今为止，Psds 在植物病原真菌中的功能尚不完全清楚。在这项研究中，我们表征了禾谷镰刀菌中的两种酵母 Psd 直向同源物：FgPsd1 和 FgPsd2 。我们的结果表明 FgPsd1 和 FgPsd2 分别位于线粒体和高尔基体中。此外，我们已经确定FgPsd1是一种致死基因，FgPsd2 的缺失导致菌丝体生长和分生孢子形成的显着减少。此外，FgPsd2缺失突变体（ΔFgPsd2）在小麦子囊孢子的产生和毒力方面存在缺陷。我们的研究还发现 ΔFgPsd2 突变体对渗透压和氧胁迫更敏感。此外，FgPsd2 的删除减少了脂滴的形成并加剧了禾谷镰刀菌中的自噬。总之，我们的研究结果表明，FgPsd2是菌丝生长，有性和无性繁殖，毒力，脂滴的形成和自噬在重要的禾谷镰刀菌。