Phosphate plays a crucial role in phospholipid metabolism and it is transported by the phosphate (Pi) transporters. Phospholipids are building blocks of the cell membrane, and essential for cell growth; however, the role of phosphate transporters in lipid metabolism remains elusive. The present study shows that the deletion of Pi transporters exhibited an increase in both phospholipid and neutral lipid levels when compared to wild type. The mRNA expressions of genes involved in phospholipid synthesis (CKI1, EKI1, CHO2, and OPI3) were increased due to de-repression of the transcription factors (INO2 and INO4). Neutral lipid levels (triacylglycerol and sterol ester) and their synthesizing genes (LRO1, ARE2, ACC1, and FAS1) were also increased, resulting in lipid droplet accumulation in Pi transporter mutants. Interestingly, phospholipase (PLC1) and histone acetyltransferase genes (ESA1, EAF1, YNG1, YNG2, and GCN5) were also found to be significantly increased, leading to dysregulation of lipid levels in Pi transporter mutants. In summary, our results suggest that the Pi transporters are involved in lipid droplet and membrane lipid homeostasis.

磷酸盐在磷脂代谢中起着至关重要的作用，并且通过磷酸盐（Pi）转运蛋白转运。磷脂是细胞膜的组成部分，对细胞生长至关重要。然而，磷酸盐转运蛋白在脂质代谢中的作用仍然难以捉摸。本研究表明，与野生型相比，Pi转运蛋白的缺失在磷脂和中性脂质水平上均表现出增加。由于转录因子（INO2和INO4）的抑制，使参与磷脂合成的基因（CKI1，EKI1，CHO2和OPI3）的mRNA表达增加。中性脂质水平（三酰基甘油和固醇酯）及其合成基因（LRO1，ARE2，ACC1，和FAS1）也增加，导致脂质转运Pi突变体中的液滴累积。有趣的是，还发现磷脂酶（PLC1）和组蛋白乙酰转移酶基因（ESA1，EAF1，YNG1，YNG2和GCN5）显着增加，导致Pi转运蛋白突变体中脂质水平失调。总而言之，我们的结果表明Pi转运蛋白参与脂质滴和膜脂质稳态。