Evidence that herpes simplex virus VP16 is required for viral egress downstream of the initial envelopment event
Evidence that herpes simplex virus VP16 is required for viral egress downstream of the initial envelopment event
复制标题
DOI：
10.1128/jvi.74.14.6287-6299.2000
复制
发表时间：
2000-07-01
影响因子：
5.4
通讯作者：
Smiley, JR
中科院分区：
文献类型：
--
作者：
Mossman, KL;Sherburne, R;Smiley, JR
在单纯疱疹病毒1型（HSV-1）感染期间，VP 16发挥多种功能，包括病毒立即早期基因的转录激活和病毒体宿主关闭蛋白vhs的下调。此外，已显示VP 16参与病毒组装和/或成熟的某些方面。用VP 16无效病毒8 MA进行的实验表明，VP 16在病毒体组装中起直接作用，因为从HSV-1基因组中去除VP 16导致减少水平的双核苷酸化DNA和不能产生细胞外包膜颗粒。然而，VP 16无效突变体显示出严重的翻译停滞，由于不受限制的vhs活性，从而复杂的解释这些数据。我们在这里研究的作用，VP 16在病毒粒子组装和出口的背景下，vhs空，使用病毒8 MA/Δ Sma（VP 16（-）vhs（-））。比较8 MA和8 MA/Δ Sma的病毒DNA积累和主要衣壳蛋白VP 5的降解和积累，揭示8 MA致死表型仅部分是由于不受控制的vhs活性，表明VP 16是HSV-1病毒体形成所需的。电子显微镜证实了这些结果，并进一步表明，VP 16是所需的HSV-1出口超出核周空间。此外，我们描述了分离和表征的8 MA衍生物能够在Vero细胞上繁殖，由于第二个位点突变的VHS和UL 53（GK）基因。总之，这些结果表明，VP 16是病毒在初始清除步骤下游流出所必需的，并进一步强调了VP 16在控制感染细胞内vhs活性中的重要性。
During infection with herpes simplex virus type 1 (HSV-1), VP16 serves multiple functions, including transcriptional activation of viral immediate early genes and downregulation of the virion host shutoff protein vhs. Furthermore, VP16 has been shown to be involved in some aspect of virus assembly and/or maturation. Experiments,vith a VP16 null virus, 8MA, suggested that VP16 plays a direct role in virion assembly, since removal of VP16 from the HSV-1 genome results in reduced levels of encapsidated DNA and a failure to produce extracellular enveloped particles. However, VP16 null mutants display a severe translational arrest due to unrestrained vhs activity, thus complicating interpretation of these data. We examine here the role of VP16 in virion assembly and egress in the context of a vhs null background, using the virus 8MA/Delta Sma (VP16(-) vhs(-)). Comparison of 8MA and 8MA/Delta Sma with respect to viral DNA accumulation and encapsidation and accumulation of the major capsid protein, VP5, revealed that the 8MA lethal phenotype is only partially due to uncontrolled vhs activity, indicating that VP16 is required in HSV-1 virion formation. Electron microscopy confirmed these results and further showed that VP16 is required for HSV-1 egress beyond the perinuclear space. In addition, we describe the isolation and characterization of an 8MA derivative capable of propagation on Vero cells, due to second site mutations in the vhs and UL53 (gK) genes. Taken together, these results show that VP16 is required for viral egress downstream of the initial envelopment step and further underscore the importance of VP16 in controlling vhs activity within an infected cell.