HERPES SIMPLEX VIRUS MULTIPLICATION

单纯疱疹病毒1型和2型（HSV-1和HSV-2）的新复制的DNA分子 HSV-2）由头-尾串联体组成，最有可能通过滚动产生 循环复制 大的多联体随后被切割成 产生单位长度的分子，其被包装成病毒核衣壳。 切割发生在位于连接处的a序列内， 相邻的病毒基因组。 在以前的研究中， 我们已经聘请了一个项目，构建有缺陷的病毒基因组，以调查 多联体分裂的机制。 构建缺陷基因组 通过种子单体重复序列的复制产生多联体 含有病毒DNA复制起点和α序列，含有 裂解/包装信号。 这些研究表明， 切割与病毒DNA的包装偶联。 的分析 多联体连接和产生的末端的结构特征， 包装和游离的核和细胞质DNA已经提供了证据， 关于裂解/包装过程的细节，包括 识别位于播放序列内的两个信号 在切割/包装中的不同作用;序列的扩增 与切割结合，扫描病毒DNA多联体 在对直接重复的包含终端的序列进行封装期间， 切割信号，以及对全长双核苷酸化DNA的要求 基因组进一步成熟的核衣壳到包膜 细胞质病毒体。 在此基础上，建立了两个模型 为了解释标准序列的已知性质， 缺陷病毒DNA 我们现建议进行三组研究， 分析包装过程中的早期事件。 的第一集合中 我们将继续研究的机制， 多联体DNA切割，通过测试和完善的各种功能， 提出的模型。 在第二组研究中，我们将继续我们的 包装过程中的体内中间体分析。 第三组 的研究将试图开发一种体外系统的切割和 可能是HSV DNA的降解。 预计这些研究将 独特地增加了我们对构成高潮的事件的理解 感染周期，并涉及高度特异性的DNA-蛋白质， 蛋白质相互作用

Newly replicated DNA molecules of herpes simplex viruses 1 and 2 (HSV-1 and HSV-2) consist of head-to-tail concatemers arising most likely by rolling circle replication. The large concatemers are subsequently cleaved to generate unit length molecules which are packaged into viral nucleocapsids. Cleavage occurs within the a sequences situated at the junctions between adjacent viral genomes in the concatemers. In previous studies under this project we have employed constructed defective virus genomes to investigate the mechanisms of concatemeric cleavage. Constructed defective genome concatemers were generated by replication of seed monomeric repeats containing a viral DNA replication origin and an a sequence, containing a cleavage/packaging signal. These studies have revealed that concatemeric cleavage was coupled to the packaging of viral DNA. Analyses of the structural features of concatemeric junctions and generated termini in packaged and free nuclear and cytoplasmic DNAs have yielded evidence concerning details of the cleavage/packaging process, including the recognition of two signals located within the a sequence which play distinct roles in the cleavage/packaging; the amplification of a sequences which is coupled to cleavage, the scanning of the viral DNA concatemers during packaging for a directly repeated a sequence containing the terminal cleavage signal, and the requirement for full length encapsidated DNA genomes for further maturation of nuclear capsids into enveloped cytoplasmic virions. On the basis of the data two models were formulated to explain the known properties of a sequences in standard as well as defective virus DNA. We now propose three sets of studies to continue our analyses of early events in the packaging process. In the first set of studies we will continue our investigations of the mechanism of concatemeric DNA cleavage, through testing and refining various features of the models proposed. In the second set of studies we will continue our analyses of in vivo intermediates in the packaging process. The third set of studies will attempt to develop an in vitro system for the cleavage and possibly encapsidation of HSV DNA. It is expected that these studies will uniquely increase our understanding of events constituting the culmination of the infectious cycle, and involving highly specific DNA-protein and protein-protein interactions.