De Sena J, Heifner W R, Stolov N S
Virology. 1983 Jul 30;128(2):354-65. doi: 10.1016/0042-6822(83)90262-3.
Previous studies in our laboratory on the in vitro uncoating of poliovirus have shown that HeLa cell membrane contains a modifying factor which induces early modification of virus (the loss of VP4) and a stabilizing factor which protects virus against heat-induced degradation. It has now been found that membrane-modifying factor is dependent on the presence of phospholipid for activity. Modifying activity was lost after exposure of membrane (Mem) to phospholipase C. Triton X-100-solubilized modifying factor prepared from phospholipase C-treated Mem was reactivated by phospholipid. Lecithin, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin were found to exhibit a reactivating effect. Lecithin was the most effective individual phospholipid in terms of maximal reactivation. Partial purification of Triton X-100-solubilized modifying factor was achieved by concanavalin A-Sepharose chromatography. Membrane-stabilizing factor was extracted from HeLa cell membrane by solubilization with sodium deoxycholate (DOC). Some properties of DOC-solubilized stabilizing factor were studied. The solubilized stabilizing factor was inactivated by treatment with trypsin or chymotrypsin. Treatment of the solubilized stabilizing factor with certain lipid solvents, lipolytic enzymes, or lectins had no detectable effect on stabilizing activity.
我们实验室之前关于脊髓灰质炎病毒体外脱壳的研究表明，HeLa细胞膜含有一种修饰因子，可诱导病毒早期修饰（VP4丢失），以及一种稳定因子，可保护病毒免受热诱导的降解。现已发现，膜修饰因子的活性依赖于磷脂的存在。将膜（Mem）暴露于磷脂酶C后，修饰活性丧失。用磷脂酶C处理的Mem制备的Triton X-100溶解的修饰因子可被磷脂重新激活。发现卵磷脂、磷脂酰乙醇胺、磷脂酰丝氨酸和鞘磷脂具有重新激活作用。就最大重新激活而言，卵磷脂是最有效的单一磷脂。通过伴刀豆球蛋白A-琼脂糖层析对Triton X-100溶解的修饰因子进行了部分纯化。用脱氧胆酸钠（DOC）溶解从HeLa细胞膜中提取膜稳定因子。研究了DOC溶解的稳定因子的一些特性。用胰蛋白酶或糜蛋白酶处理可使溶解的稳定因子失活。用某些脂质溶剂、脂解酶或凝集素处理溶解的稳定因子对稳定活性没有可检测的影响。
