HSV 1 PROCESSING/PACKAGING GENES

单纯疱疹病毒在人群中流行，是多种临床疾病的原因，其中一些是危及生命的，特别是在免疫功能低下的个体或新生儿中。通过对病毒突变体的分析发现，病毒基因组成熟和衣壳化的过程似乎是一个涉及至少8种病毒基因产物功能的多步骤操作。这些病毒基因（UL6、UL12、UL15、ul7、UL25、UL28、UL32和UL33）在疱疹病毒家族中保存良好，表明它们可能在病毒生命周期中发挥重要作用。本提案的目的是通过遗传和生化分析提供对基因组加工和包装事件的更好理解。第一个目的是确定UL15和UL28在切割和包装中的作用。我们计划验证这些蛋白质编码假定的终止酶/转位酶的假设。为此，我们将尝试纯化可溶性UL15/UL28蛋白复合物，并对终止酶的预期功能进行生化测试。我们还将扩展这两个基因产物的遗传分析。第二个目标是进一步表征UL6和UL32的作用。初步证据表明UL6可能作为一种门静脉蛋白，而UL32是衣壳在感染细胞中正确定位所必需的。这些分配将通过基因分析进行测试。第三个目标是继续鉴定与原囊体相关的切割和包装蛋白，这些原囊体是从被囊化过程中不同阶段阻断的突变体感染的细胞中分离出来的。预计这种类型的分析将为这些蛋白质的作用提供额外的线索。我们还计划在感染期间检查衣壳定位，以表征衣壳化过程的空间组织。长期目标包括体外裂解和包装反应的发展。预计这一建议不仅将增强我们对基因组成熟和衣壳化机制的理解，而且可能导致抗病毒治疗新策略的发展。

Herpes simplex viruses are endemic in the population and are responsible for a variety of clinical diseases some of which are life threatening, especially in immunocompromised individuals or in newborns. The processes of viral genome maturation and encapsidation appear to be a multistep operation involving the function of at least eight viral gene products as revealed by the analysis of viral mutants. These viral genes (UL6, UL12, UL15, ULI7, UL25, UL28, UL32 and UL33) are well conserved within the herpesvirus family indicating that they likely play important roles in the viral life cycle. The objective of this proposal is to provide a better understanding of the events of genome processing and packaging through genetic and biochemical analysis. The first aim is to determine the role of UL15 and UL28 in cleavage and packaging. We plan to test the hypothesis that these proteins encode the putative terminase/translocase. To this end we will attempt to purify a soluble UL15/UL28 protein complex and test biochemically for functions expected of a terminase. We also will extend our genetic analysis of these two gene products. The second aim is to further characterize the roles of UL6 and UL32. Preliminary evidence suggests that UL6 may act as a portal protein and the UL32 is required for capsids to localize correctly in infected cells. These assignments will be tested by genetic analysis. The third aim is to continue the identification of the cleavage and packaging proteins that are associated with procapsids isolated from cells infected with mutants blocked at various stages in the encapsidation process. It is anticipated that this type of analysis will provide additional clues about the roles of these proteins. We also plan to examine capsid localization during infection to characterize the spatial organization of the encapsidation process. Long term aims include the development of an in vitro cleavage and packaging reaction. It is anticipated that this proposal will not only enhance our understanding of the mechanisms of genome maturation and encapsidation but may also lead to the development of novel strategies for antiviral therapy.