A mutation in UL15 of herpes simplex virus 1 that reduces packaging of cleaved genomes.
A mutation in UL15 of herpes simplex virus 1 that reduces packaging of cleaved genomes.
复制标题
单纯疱疹病毒 1 的 UL15 发生突变，可减少切割基因组的包装。
DOI：
10.1128/jvi.00857-11
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发表时间：
2011
影响因子：
5.4
通讯作者：
Baines,JoelD
中科院分区：
文献类型：
--
作者：
Yang,Kui;Wills,ElizabethG;Baines,JoelD
疱疹病毒基因组DNA从在感染的细胞核中积累的多联体切割。基因组DNA通过独特的门户顶点插入到预组装的衣壳中。病毒突变体的广泛分析表明，完整的衣壳，门户顶点，和一个三方终止酶的所有组件都需要切割和包装病毒DNA，这表明DNA切割和包装是密不可分的。由于这些过程在功能上是不可分离的，因此很难解析单个蛋白质在DNA切割/包装反应中的作用。在本研究中，分析了编码终止酶组分的UL 15的密码子400至420缺失的病毒。这种病毒，命名为vJB 27，不能在非互补细胞上复制，但切割多联体DNA，使其与非互补细胞结合。野生型水平的35%至98%。在用UL 15无效病毒或缺乏UL 15密码子383至385的病毒感染的细胞中未检测到DNA切割，所述密码子383至385包含建议将ATP水解与DNA易位偶联的基序。与野生型病毒相比，保护免于DNA酶I消化的vJB 27 DNA的量减少了6.5至200倍，这取决于所分析的DNA片段，因此表明DNA包装存在严重缺陷。电子显微镜检查显示，在vJB 27感染的细胞中未检测到含有病毒DNA的衣壳。这些数据表明，pUL 15在DNA易位到衣壳中起着重要作用，并表明这种功能是从它的作用在DNA切割分离。
Herpesvirus genomic DNA is cleaved from concatemers that accumulate in infected cell nuclei. Genomic DNA is inserted into preassembled capsids through a unique portal vertex. Extensive analyses of viral mutants have indicated that intact capsids, the portal vertex, and all components of a tripartite terminase enzyme are required to both cleave and package viral DNA, suggesting that DNA cleavage and packaging are inextricably linked. Because the processes have not been functionally separable, it has been difficult to parse the roles of individual proteins in the DNA cleavage/packaging reaction. In the present study, a virus bearing the deletion of codons 400 to 420 of UL15, encoding a terminase component, was analyzed. This virus, designated vJB27, failed to replicate on noncomplementing cells but cleaved concatemeric DNA to ca. 35 to 98% of wild-type levels. No DNA cleavage was detected in cells infected with a UL15-null virus or a virus lacking UL15 codons 383 to 385, comprising a motif proposed to couple ATP hydrolysis to DNA translocation. The amount of vJB27 DNA protected from DNase I digestion was reduced compared to the wild-type virus by 6.5- to 200-fold, depending on the DNA fragment analyzed, thus indicating a profound defect in DNA packaging. Capsids containing viral DNA were not detected in vJB27-infected cells, as determined by electron microscopy. These data suggest that pUL15 plays an essential role in DNA translocation into the capsid and indicate that this function is separable from its role in DNA cleavage.