McGeady M L, Crowell R L
J Virol. 1979 Dec;32(3):790-5. doi: 10.1128/JVI.32.3.790-795.1979.
Previous studies in our laboratory showed that HeLa cell plasma membranes were recovered from sucrose gradients in two major bands and that the heavier band possessed a putative inhibitor of uncoating of coxsackievirus B3. It has now been found that the mechanism of inhibition is the stabilization of "A" particles against inactivation at 37 degrees C. [3H]uridine-labeled virions converted to A particles by band 4, the heavier band, were four times more stable at 37 degrees C than those produced by band 3. Partially purified A particles from both bands were equally unstable. It was found that the stabilizing factor was extractable by saline from band 4 and remained soluble after centrifugation (109,000 X g for 2 h). Addition to A particles of this soluble factor isolated from either band 4 or band 3 stabilized the A particles. The stabilizing factor could not be replaced by an extract from band 3 or by bovine serum albumin. Thus, the finding that the membrane factor inhibits virus uncoating by stabilizing A particles against spontaneous disruption at 37 degrees C focuses attention on an inherent problem associated with defining receptor-mediated virus uncoating.
我们实验室之前的研究表明，从蔗糖梯度中回收的HeLa细胞质膜存在于两个主要条带中，较重的条带含有一种推测的柯萨奇病毒B3脱壳抑制剂。现已发现，抑制机制是使“A”颗粒稳定，防止其在37℃失活。由较重的条带4转化为“A”颗粒的[3H]尿苷标记病毒粒子在37℃时的稳定性是由条带3产生的病毒粒子的四倍。来自两个条带的部分纯化“A”颗粒同样不稳定。结果发现，稳定因子可被盐水从条带4中提取出来，离心后（109,000×g，2小时）仍保持可溶。将从条带4或条带3分离出的这种可溶因子添加到“A”颗粒中，可使“A”颗粒稳定。稳定因子不能被条带3的提取物或牛血清白蛋白替代。因此，膜因子通过使“A”颗粒在37℃下稳定以防止自发破坏来抑制病毒脱壳这一发现，将注意力集中在与定义受体介导的病毒脱壳相关的一个固有问题上。
