Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Center for Translational Biomedical Research, The University of North Carolina at Greensboro, Kannapolis, NC, USA.
Sci Adv. 2023 Oct 20;9(42):eadj4198. doi: 10.1126/sciadv.adj4198.
Virus-induced changes in host lipid metabolism are an important but poorly understood aspect of viral pathogenesis. By combining nontargeted lipidomics analyses of infected cells and purified extracellular quasi-enveloped virions with high-throughput RNA sequencing and genetic depletion studies, we show that hepatitis A virus, an hepatotropic picornavirus, broadly manipulates the host cell lipid environment, enhancing synthesis of ceramides and other sphingolipids and transcriptionally activating acyl-coenzyme A synthetases and fatty acid elongases to import and activate long-chain fatty acids for entry into the fatty acid elongation cycle. Phospholipids with very-long-chain acyl tails (>C22) are essential for genome replication, whereas increases in sphingolipids support assembly and release of quasi-enveloped virions wrapped in membranes highly enriched for sphingomyelin and very-long-chain ceramides. Our data provide insight into how a pathogenic virus alters lipid flux in infected hepatocytes and demonstrate a distinction between lipid species required for viral RNA synthesis versus nonlytic quasi-enveloped virus release.
病毒诱导的宿主脂质代谢变化是病毒发病机制的一个重要但尚未被充分了解的方面。通过对感染细胞和纯化的细胞外准包膜病毒进行非靶向脂质组学分析,并结合高通量 RNA 测序和遗传耗竭研究,我们表明甲型肝炎病毒(一种嗜肝小 RNA 病毒)广泛地操纵宿主细胞的脂质环境,增强神经酰胺和其他鞘脂的合成,并转录激活酰基辅酶 A 合成酶和脂肪酸延长酶,以导入和激活长链脂肪酸进入脂肪酸延长循环。具有超长链酰基尾(>C22)的磷脂对于基因组复制是必需的,而鞘脂的增加则支持包膜准病毒颗粒的组装和释放,这些病毒颗粒被富含鞘磷脂和超长链神经酰胺的膜包裹。我们的数据提供了对致病病毒如何改变感染肝细胞中脂质通量的深入了解,并证明了病毒 RNA 合成与非裂解性准包膜病毒释放所需的脂质种类之间的区别。