Spring S B, Roizman B
J Virol. 1968 Oct;2(10):979-85. doi: 10.1128/JVI.2.10.979-985.1968.
Approximately 67% of infectivity is associated with the nucleus 8 hr after productive infection of HEp-2 cells with herpes simplex virus. Comparison of nuclear and cytoplasmic infectious virus and macromolecular aggregates labeled with (3)H-thymidine or with (3)H-choline revealed the following. (i) Cytoplasmic infectious virus and macromolecular aggregates banded in CsCl at a density corresponding to enveloped nucleocapsids. The virus was relatively stable; there was only 50% loss of infectivity and only 16% of the virions became disaggregated. (ii) Nuclear macromolecular aggregates banded in CsCl solution at a density corresponding to unenveloped nucleocapsids and, moreover, both the infectious virus and aggregates were highly unstable. (iii) In sucrose density gradients, the nuclear macromolecular aggregates and infectivity sedimented as a single band and migrated more slowly than the corresponding cytoplasmic material. (iv) The infectivity of nuclear and cytoplasmic virus is readily inactivated by digestion with phospholipase C and with pronase. We conclude the following. (i) Cytoplasmic virus consists of enveloped nucleocapsids. (ii) Nuclear virus consists of nucleocapsids covered with lipid or partially enveloped. (iii) The molecular integrity of viral lipids is essential for infectivity. (iv) The envelope protects the nucleocapsid and accelerates adsorption to cells; it is not, however, inherently essential for infectivity.
用单纯疱疹病毒有效感染人喉表皮癌细胞（HEp-2细胞）8小时后，约67%的感染性与细胞核相关。对用³H-胸腺嘧啶核苷或³H-胆碱标记的细胞核和细胞质中的感染性病毒及大分子聚集体进行比较，结果如下：（i）细胞质中的感染性病毒及大分子聚集体在氯化铯中的密度与包膜核衣壳相对应，病毒相对稳定，感染性仅损失50%，只有16%的病毒粒子发生解聚。（ii）细胞核中的大分子聚集体在氯化铯溶液中的密度与无包膜核衣壳相对应，而且感染性病毒和聚集体都极不稳定。（iii）在蔗糖密度梯度中，细胞核中的大分子聚集体和感染性物质以单一条带形式沉降，且比相应的细胞质物质迁移得更慢。（iv）细胞核和细胞质病毒的感染性很容易被磷脂酶C和链霉蛋白酶消化而失活。我们得出以下结论：（i）细胞质病毒由包膜核衣壳组成。（ii）细胞核病毒由覆盖有脂质或部分包膜的核衣壳组成。（iii）病毒脂质的分子完整性对感染性至关重要。（iv）包膜保护核衣壳并加速对细胞的吸附；然而，它并非感染性所必需。
