HIV-1 VPR AND BASIC CELLULAR FUNCTIONS

HIV-1 Vpr阻断宿主细胞周期进程并中断细胞骨架 结构，这两种效应可能与HIV发病机制有关。在 目前，关于Vpr如何影响这些细胞功能知之甚少 我们的研究是专门针对这个问题而设计的。 我们已经开发了一种新的裂变酵母模型系统， Vpr诱导的细胞变化与在 人体细胞与人类系统相比，裂变酵母提供了一个 一个简单但遗传上定义明确的真核系统来研究机制 在遗传和生化水平上的Vpr作用。我们计划使用 野生型和先前表征的突变体，以鉴定细胞 Vpr作用的途径并发现Vpr的功能， 这在哺乳动物细胞中尚不容易实现。的事实 p34 cdc 2、细胞周期蛋白B和其它细胞周期调控基因被 人类和裂变酵母之间的互换性使得裂变酵母 系统相关功能的研究。我们的目标是利用这个 模型系统1）定义中断蜂窝通信所需的Vpr域 功能; 2）确定细胞周期G2控制通路Vpr 影响，以及3）确定Vpr与什么基因产物相互作用。我们 初步研究表明，Vpr可能与 G2-M转换的上游调节因子，但不与基因产物 从DNA损伤途径。我们还鉴定了候选蛋白质 与Vpr结合在这项研究中，我们将精确定位细胞靶点 的Vpr的影响，并表征Vpr相互作用的蛋白质。我们将 进一步扩大我们的研究，以测试在哺乳动物中获得的结果， 系统我们期望拟议的研究将提供新的 Vpr影响宿主细胞的作用机制 功能和HIV发病机制。

HIV-l Vpr blocks host cell cycle progression and interrupts cytoskeletal structures, two effects which may be related to HIV pathogenesis. At present, little is known about how Vpr affects these cellular functions and our studies are designed specifically to address this question. We have developed a novel fission yeast model system, in which we found that Vpr-induced cellular changes were very similar to those observed in human cells. As compared with human systems, fission yeast offers a simple yet genetically well-defined eukaryotic system to study mechanisms of Vpr action at both genetic and biochemical levels. We plan to use wild-type and previously characterized mutants to identify cellular pathways on which Vpr impinges and to discover the function of Vpr, something that cannot yet be done easily in mammalian cells. The fact that p34cdc2, cyclin B and other cell cycle control genes are interchangeable between human and fission yeast makes the fission yeast system relevant for studying related functions. Our goal is to use this model system l) to define domains of Vpr required to interrupt cellular functions; 2) to identify which cell cycle G2 control pathway(s) Vpr affects, and 3) to determine what gene product(s) Vpr interacts with. Our preliminary studies indicated that Vpr is likely interacting with upstream regulators of the G2-M transition but not with gene products from the DNA damage pathway. We have also identified protein candidates that bind to Vpr. In this study, we will pinpoint the cellular targets of the Vpr effects and characterize the Vpr-interacting proteins. We will further expand our studies to test the obtained results in a mammalian system. It is our expectation that the proposed studies will provide new insights into the mechanism of action of Vpr on affecting host cell functions and HIV pathogenesis.