Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 117543, Singapore.
Virology. 2010 Apr 10;399(2):248-56. doi: 10.1016/j.virol.2010.01.016. Epub 2010 Feb 2.
Singapore grouper iridoviruses (SGIV) infected grouper cells release few enveloped extracellular viruses by budding and many unenveloped intracellular viruses following cell lysis. The lipid composition and function of such unenveloped intracellular viruses remain unknown. Detergent treatment of the intracellular viruses triggered the loss of viral lipids, capsid proteins and infectivity. Enzymatic digestion of the viral lipids with phospholipases and sphingomyelinase retained the viral capsid proteins but reduced infectivity. Over 220 lipid species were identified and quantified from the viruses and its producer cells by electrospray ionization mass spectrometry. Ten caspid proteins that dissociated from the viruses following the detergent treatments were identified by MALDI-TOF/TOF-MS/MS. Five of them were demonstrated to be lipid-binding proteins. This is the first research detailing the lipidome and lipid-protein interactions of an unenveloped virus. The identified lipid species and lipid-binding proteins will facilitate further studies of the viral assembly, egress and entry.
新加坡石斑鱼虹彩病毒（SGIV）感染的石斑鱼细胞通过出芽释放少量包膜细胞外病毒，而在细胞裂解后则释放大量无包膜细胞内病毒。这些无包膜细胞内病毒的脂质组成和功能尚不清楚。去污剂处理细胞内病毒会导致病毒脂质、衣壳蛋白和感染性丧失。用磷脂酶和鞘磷脂酶对病毒脂质进行酶消化可保留病毒衣壳蛋白，但会降低感染性。通过电喷雾电离质谱法从病毒及其产生细胞中鉴定和定量了超过 220 种脂质。通过 MALDI-TOF/TOF-MS/MS 鉴定了 10 种在去污剂处理后从病毒中分离出来的衣壳蛋白。其中 5 种被证明是与脂质结合的蛋白。这是首次详细研究无包膜病毒的脂质组和脂质-蛋白相互作用。鉴定出的脂质种类和与脂质结合的蛋白将有助于进一步研究病毒的组装、出芽和进入。
