Pawliczek Tobias, Crump Colin M
Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, United Kingdom.
J Virol. 2009 Nov;83(21):11254-64. doi: 10.1128/JVI.00574-09. Epub 2009 Aug 19.
Herpes simplex virus type 1 (HSV-1) acquires its mature virus envelope by budding into the lumen of cytoplasmic membranous compartments carrying the viral glycoproteins. In a cellular context, a budding process with identical topology occurs during the formation of intraluminal vesicles in multivesicular bodies. The cellular machinery that mediates this budding process is composed of four protein complexes termed endosomal sorting complexes required for transport (ESCRTs) and several associated proteins, including the ATPase VPS4. We have recently shown that functional VPS4 is specifically required for the cytoplasmic envelopment of HSV-1. We now demonstrate that, consistent with a role of VPS4 in virus envelopment, dominant-negative ESCRT-III proteins potently block HSV-1 production. Retroviruses are known to recruit the ESCRT machinery by small peptide motifs termed late domains. These late domains interact with various ESCRT components and thereby promote ESCRT recruitment. The best-characterized late-domain interacting ESCRT proteins are ALIX and TSG101. The presence of potential ALIX and TSG101 binding sequence motifs in various structural HSV-1 proteins suggested a functional role of these proteins in HSV-1 envelopment. We therefore used a set of dominant-negative proteins, as well as RNA interference, to characterize the contribution of ALIX and TSG101 to HSV-1 production. Interestingly, despite the strict requirement for a functional ESCRT-III complex, our data suggest that HSV-1 production is independent of ALIX and TSG101 expression. In line with these data, we also find that ESCRT-III proteins and VPS4A/B are specifically incorporated into mature HSV-1 virions.
单纯疱疹病毒1型(HSV-1)通过出芽进入携带病毒糖蛋白的细胞质膜性区室腔来获得其成熟病毒包膜。在细胞环境中,多泡体中腔内小泡形成过程中会发生拓扑结构相同的出芽过程。介导这一出芽过程的细胞机制由四种称为转运所需内体分选复合体(ESCRT)的蛋白质复合体以及几种相关蛋白组成,包括ATP酶VPS4。我们最近发现功能性VPS4是HSV-1细胞质包膜形成所特需的。我们现在证明,与VPS4在病毒包膜形成中的作用一致,显性负性ESCRT-III蛋白能有效阻断HSV-1的产生。已知逆转录病毒通过称为晚期结构域的小肽基序招募ESCRT机制。这些晚期结构域与各种ESCRT组分相互作用,从而促进ESCRT的招募。特征最明确的与晚期结构域相互作用的ESCRT蛋白是ALIX和TSG101。各种HSV-1结构蛋白中存在潜在的ALIX和TSG101结合序列基序,提示这些蛋白在HSV-1包膜形成中具有功能作用。因此,我们使用了一组显性负性蛋白以及RNA干扰来确定ALIX和TSG101对HSV-1产生的作用。有趣的是,尽管严格需要功能性的ESCRT-III复合体,但我们的数据表明HSV-1的产生不依赖于ALIX和TSG101的表达。与这些数据一致,我们还发现ESCRT-III蛋白和VPS4A/B特异性地整合到成熟的HSV-1病毒粒子中。