REGULATION OF HIV GENE EXPRESSION

人类免疫缺陷病毒（HIV）基因表达的调控是 依赖于长末端重复序列中的特定调控序列。 对病毒基因调控重要的元件 表达包括IL-2样增强子序列、负调控增强子序列和增强子序列。 元件，含有两个NF-κ B基序的增强子，三个SP1结合位点， TATA元件和TAR区域。这些调控序列用作 细胞转录因子的结合位点。多个蜂窝 与这些DNA位点结合的蛋白质的特征包括 NFAT-1，其结合IL-2样增强子元件; EBP-1和NF-κ B， 它与增强子SP-1结合，SP-1与三个SP1结合位点结合， 位点;结合TAR区域的UBP-1或LBP、UBP-2和CTF。在 除了这些调节序列之外，病毒调节蛋白，达特， 用于增强病毒基因表达。 这项资助的目标是了解这些监管要素和 它们的结合蛋白在激活HIV基因表达中起作用。几 将采取各种办法来解决这些问题。第一，传染性 在各种LTR调节结构域中含有突变的病毒构建体 将进行研究，以确定这些突变对病毒 增长第二，TAR区域在HIV LTR的达特活化中的作用 将通过使用HIV LTR的核运行实验来确定， 各种异源TAR构建体，以及DNA和RNA竞争 实验第三，我们将研究克隆细胞因子的作用， 结合IL-2样增强子序列的增强子，增强子和UBP-L结合 在TAR区域的位点对HIV基因表达的调节。最后， 突变的达特蛋白在调节病毒基因表达中的作用将是 研究了这些研究应进一步确定细胞和病毒 调节HIV基因表达的机制。

The regulation of human immunodeficiency virus (HIV) gene expression is dependent on specific regulatory sequences in the long terminal repeat. Elements that appear to be important for regulation of viral gene expression include IL-2-like enhancer sequences, negative regulatory elements, an enhancer containing two NF-kB motifs, three SP1 binding sites, the TATA element, and the TAR region. These regulatory sequences serve as the binding sites for cellular transcription factors. A number of cellular proteins that bind to these DNA sites have been characterized including NFAT-1, which binds to the IL-2 like enhancer elements; EBP-1 and NF-kB, which bind to the enhancer, SP-1, which binds to the three SP1 binding sites; UBP-1 or LBP, UBP-2, and CTF which bind to the TAR region. In addition to these regulatory sequences, the viral regulatory protein, tat, acts to enhance viral gene expression. The goal of this grant is to understand how these regulatory elements and their binding proteins function in activating HIV gene expression. Several approaches will be undertaken to address these questions. First, infectious viral constructs containing mutations in various LTR regulatory domains will be studied to determine the effects of these mutations on viral growth. Second, the role of the TAR region on tat activation of the HIV LTR will be determined by nuclear run-on experiments using the HIV LTR, a variety of heterologous TAR constructs, and DNA and RNA competition experiments. Third, we will investigate the role of cloned cellular factors that bind to IL-2 like enhancer sequences, the enhancer, and UBP-L binding sites in the TAR region on the regulation of HIV gene expression. Finally, the role of mutant tat proteins on regulating viral gene expression will be investigated. These studies should further define cellular and viral regulatory mechanisms that mediate HIV gene expression.