ROLE OF INTRACELLULAR TRAFFIC IN HIV INFECTION

病毒成分必须通过核膜运输 发生在人类生命周期的许多阶段 免疫缺陷病毒（HIV）和其他逆转录病毒。 一旦进入 在细胞质中，HIV RNA被逆转录成双链DNA 然后进入细胞核 越来越多的证据表明 HIV的病毒基质蛋白作为细胞核的介体， 交通事件。 基质蛋白已被分离重组 形式和其核定位检查。其它逆转录病毒 调节蛋白也进入细胞核以执行它们的功能， 病毒转录物被输出到细胞质中。 病毒 蛋白质，rev和达特，已经被鉴定为细胞凋亡的关键调节因子。 HIV包膜mRNA的转录和运输出细胞核。 这些蛋白质包含的序列是必要的，足以 靶向细胞核。 使用透化的体外系统 细胞已被开发来检查核仁靶向的 携带这种靶向信号的蛋白质。 我们观察到 向核仁的运输是一个主动过程。 除了其 核仁转运REV从细胞核主动输出。而 已确定介导rev核输出的特定信号 对蛋白质输出的机制知之甚少。 审查这个 我们构建了一种嵌合蛋白， 的rev偶联到绿色荧光蛋白（GFP）。 奇美拉 还含有糖皮质激素的类固醇结合结构域 受体，从而可以精确控制核进口。 此外 导致核运输;去除激素启动 导出，但不允许后续导入。 这些方法应 让我们能够分析和生化解剖核出口 过程

Viral components must be transported across the nuclear membrane occurs at numerous steps in the life cycle of the human immunodeficiency virus (HIV) and other retroviruses. Once in the cytoplasm, HIV RNA is reverse-transcribed into double-stranded DNA which then enters the nucleus. A growing amount of evidence points to the viral matrix protein of HIV as a mediator of the nuclear transport event. The matrix protein has been isolated in recombinant form and its nuclear localization examined. Other retroviral regulatory proteins also enter the nucleus to perform their function, and viral transcripts are exported out to the cytoplasm. The viral proteins, rev and tat, have been identified as a key regulators of the transcription and transport of HIV envelope mRNA out of the nucleus. These proteins contain sequences that are necessary and sufficient for targeting to the nucleolus. An in vitro system using permeabilized cells has been developed to examine the nucleolar targeting of proteins bearing such targeting signals. We have observed that transport to the nucleolus is an active process. In addition to its nucleolar transport rev is actively exported from the nucleus. While a specific signal mediating nuclear export of rev has been identified the mechanism of protein export is poorly understood. To examine this nuclear export event we have constructed a chimeric protein consisting of rev coupled to the green fluorescent protein (GFP). The chimera also contains the steroid binding domain of the glucocorticoid receptor thus allowing precise control over nuclear import. Addition of hormone leads to nuclear transport; removal of hormone initiates export but does not allow subsequent import. These approaches should allow us to analyze and biochemically dissect the nuclear export process.