Alphaherpesvirus tegument assembly, secondary envelopment, and exocytosis processes are understood in broad strokes, but many of the individual steps in this pathway, and their molecular and cell biological details, remain unclear. Viral tegument and membrane proteins form an extensive and robust protein interaction network, such that essentially any structural protein can be deleted, yet particles are still assembled, enveloped, and released from infected cells. We conceptually divide the tegument proteins into three groups: conserved inner and outer teguments that participate in nucleocapsid and membrane contacts, respectively; and 'middle' tegument proteins, consisting of some of the most abundant tegument proteins that serve as central hubs in the protein interaction network, yet which are unique to the alphaherpesviruses. We then discuss secondary envelopment, reviewing the tegument-membrane contacts and cellular factors that drive this process. We place this viral process in the context of cell biological processes, including the endocytic pathway, ESCRT machinery, autophagy, secretory pathway, intracellular transport, and exocytosis mechanisms. Finally, we speculate about potential relationships between cellular defenses against oligomerizing or aggregating membrane proteins and the envelopment and egress of viruses.

中文翻译：

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被膜组装、二次包膜和胞吐作用。

甲疱疹病毒外皮组装、二次包膜和胞吐过程在广义上得到了理解，但该途径中的许多单独步骤及其分子和细胞生物学细节仍不清楚。病毒外皮和膜蛋白形成了广泛而强大的蛋白质相互作用网络，因此基本上任何结构蛋白都可以被删除，但颗粒仍然被组装、包裹并从受感染的细胞中释放出来。我们在概念上将外皮蛋白分为三组：分别参与核衣壳和膜接触的保守内皮和外皮；和“中间”外皮蛋白，由一些最丰富的外皮蛋白组成，在蛋白质相互作用网络中充当中心枢纽，但它们是α疱疹病毒所独有的。然后，我们讨论了二次包络，回顾了驱动这一过程的被膜-膜接触和细胞因子。我们将此病毒过程置于细胞生物学过程的背景下，包括内吞途径、ESCRT 机制、自噬、分泌途径、细胞内转运和胞吐机制。最后，我们推测细胞对低聚或聚集膜蛋白的防御与病毒的包裹和排出之间的潜在关系。