PAPILLOMAVIRUS

大多数关于哺乳动物DNA复制的现有信息 细胞来源于对裂解病毒的研究。 的一些方面 DNA复制的调节不能在这些研究中容易地进行。 系统，因为大多数裂解病毒缺乏明确定义的复制 控制 BPV作为一个稳定复制的附加体在 转化的啮齿动物细胞 因此，牛乳头瘤病毒（BPV） DNA复制为拷贝数控制和分离提供了一个模型 在哺乳动物细胞中。 拟议研究的总体目标是了解 BPV的DNA复制特性。 这些目标将通过以下方式实现： 在两个不同的层面上研究病毒的复制。 首先，详细 病毒顺式作用元件及两种病毒编码基因的研究 将承担涉及复制的交易因素。 这将有助于确定这些因素和要素在 复制过程。 这一办法将包括建立一个 BPV体外复制系统。 第二，体内研究将 启动以确定BPV如何能够 建立和维持自己作为一个 稳定质粒。 这个问题将通过详细的 体内复制的动力学分析，并通过测定 对病毒基因和病毒基因调控的拷贝数要求 控制和维护。 实验方法是将 复制所需的反式作用因子的表达， 从病毒转录控制。 这将通过 表达所需反式作用的稳定细胞系的产生 来自异源启动子的因子。 这些细胞系将用于 确定病毒基因调控在多大程度上负责 BPV的复制特性。 最后，BPV被确定为原型乳头瘤病毒， 作为复制、基因调控和转化的模型。 人乳头瘤病毒，被广泛认为是参与 在各种恶性肿瘤的发展中，最明显的是宫颈癌， 癌，很难在分子水平上研究。 虽然 对人类的复制特性知之甚少 因此，对BPV复制的研究很可能会为我们提供深入的了解。 进入人类病毒的生命周期。

Most of the existing information about DNA replication in mammalian cells comes from studies of lytic viruses. Some aspects of the regulation of DNA replication cannot be studied readily in these systems, because most lytic viruses lack a clearly defined replication control. BPV is maintained as a stable replicating episome in transformed rodent cells. Thus, study of bovine papillomavirus (BPV) DNA replication offers a model for copy number control and segregation in mammalian cells. The overall goals of the proposed research are to understand the properties of DNA replication of BPV. These goals will be addressed by studying viral replication at two different levels. First, a detailed study of the viral cis-acting elements and the two virus encoded transacting factors that are involved in replication will be undertaken. This will serve to define the role of the factors and elements in the replication process. This approach will include the establishment of an in vitro replication system for BPV. Second, in vivo studies will be initiated to determine how BPV can establish and maintain itself as a stable plasmid. This question will be addressed both by detailed kinetic analysis of replication in vivo, and by determination of the requirements for viral genes and viral gene regulation in copy number control and maintenance. The experimental approach will be to uncouple the expression of the trans-acting factors required for replication, from viral transcriptional control. This will be accomplished by generation of stable cell lines expressing the required trans-acting factors from heterologous promoters. These cell lines will be used to determine to what extent viral gene regulation is responsible for the replication properties of BPV. Finally, BPV is firmly established as the prototype papillomavirus, serving as a model for replication, gene regulation and transformation. The human papillomaviruses, which are widely considered to be involved in the development of a variety of malignancies, most notably cervical carcinomas, are difficult to study at the molecular level. Although very little is know about the replication properties of the human viruses, it is likely that study of BPV replication will furnish insight into the life cycle of the human viruses.