HIV-1 VPR AND BASIC CELLULAR FUNCTIONS

HIV-L vpr阻断宿主细胞周期进程并阻断细胞骨架 结构，这两种作用可能与HIV的发病机制有关。在… 目前，我们对vpr如何影响这些细胞功能知之甚少。 我们的研究就是专门为解决这个问题而设计的。 我们开发了一种新的裂解酵母模型系统，在该系统中，我们发现 VPR引起的细胞变化与观察到的 人类细胞。与人类系统相比，分裂酵母提供了一种 用于研究机制的简单但基因定义明确的真核系统 VPR在遗传和生化水平上的作用。我们计划使用 野生型和先前鉴定的突变体以鉴定细胞 VPR影响的路径并发现VPR的功能， 这是在哺乳动物细胞中还不容易做到的事情。事实是 P34cdc2、细胞周期蛋白B等细胞周期调控基因 可在人类和分裂酵母之间互换使分裂酵母 与学习相关功能相关的系统。我们的目标是利用这个 模型系统L)定义中断蜂窝所需的VPR的域 功能；2)确定哪个细胞周期G2调控途径(S)vpr 影响，以及3)确定vpr与什么基因产物(S)相互作用。我们的 初步研究表明，VPR很可能与 G2-M转换的上游调节因子，但不是基因产物 从DNA损伤途径。我们还确定了候选蛋白质 与VPR捆绑在一起。在这项研究中，我们将精确定位细胞靶标 并对VPR相互作用的蛋白质进行鉴定。我们会 进一步扩大我们的研究范围，在哺乳动物身上检验所获得的结果 系统。我们期望拟议的研究将提供新的 VPR影响宿主细胞作用机制的研究进展 功能与HIV的发病机制。

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.