Functional Map -- HIV Tat Second Exon in Cytokine Regulation

感染艾滋病毒和艾滋病是毁灭性的世界性健康问题。尽管在发现艾滋病毒和艾滋病之间的关系方面取得了显著进展，这大大改善了发达国家的治疗情况，但我们仍远未达到可在全世界实施的有效预防或治疗方法。因此，更好地了解病毒和宿主之间的致病关系仍然是科学的负担。事实上，有很多 一些与HFV-1相关的病理，包括HIV-1相关性痴呆(HIVD)，根本不能用病毒复制水平很好地解释，而且可能不会简单地通过有效控制复制而消失。HIV-1Tat蛋白因其在病毒转录中的作用而被广泛研究，它是一种明显的候选病毒成分，可介导一系列艾滋病毒病理，包括HIVD和卡波西氏肉瘤。TAT对这些非LTR活性的分子机制和氨基酸需求尚不清楚。此外，相对于单个外显子Tat72形式，全长Tat101蛋白已经被深入研究，特别是它通过调节宿主基因表达在HIV-1致病中的作用。这项提议试图填补这一空白。核心假设是在TAT第二外显子中有一个独特的、可定义的结构域，即在全长蛋白质的背景下，负责对宿主基因的全面调控。我们的具体目标将通过定义对目标1中两种生理相关形式的TAT(Tat72和Tat101)做出最明显差异反应的细胞因子基因来解决这一假说。在目标2中，将通过合理的靶向缺失突变方法来粗略定位第二外显子中的氨基酸区域，该外显子为全长蛋白质提供调节细胞因子基因的附加功能。最后，在目标3中，通过引入逻辑设计，对缺失分析确定的功能区域进行精细绘制 单个氨基酸替换，以测试其对细胞因子基因调控的影响。在这项研究的结论中，我们将在理解TAT第二外显子完全介导宿主基因调控的分子要求方面取得显著进展。我们将处于适当的位置，继续调查TAT 与HFV-1致病有关，因为我们将有一套独特的工具来探测接触TAT第二外显子内功能元件的细胞蛋白伙伴。我们的长期目标是使用这些工具来研究TAT蛋白在HIV-1相关病理，特别是HIVD中的生物学作用和意义。

Infection with HIV and AIDS are devastating worldwide health problems. Although progress has been outstanding in discovering the relationship between HIV and AIDS and this has resulted in dramatically improved treatment in the developed world, we are still far from effective prevention or treatment that can be implemented worldwide. Thus the burden on science to better understand the pathogenic relationship between virus and host remains. Indeed, there are some HFV-1 associated pathologies, including HIV-1 associated dementia (HIVD), that simply are not well explained by the level of viral replication and may not disappear simply with effective control of replication. The HIV-1 Tat protein, well-studied for its role in viral transcription, represents a conspicuous candidate viral component that mediates a range of HIV pathologies, including HIVD and Kaposi's sarcoma. The molecular mechanisms and amino acid requirements of Tat for these non-LTR activities remain unclear. Further the full-length Tat101 protein has been understudied relative to the single exon Tat72 form, particularly for its role in HIV-1 pathogenesis through regulation of host gene expression. This proposal seeks to fill that gap. The central hypothesis is that there is a unique, definable domain within the Tat second exon, that in the context of the full length protein, is responsible for full regulation of host genes. Our specific aims will address this hypothesis by defining the cytokine genes that respond in the most clearly differential manner to the two physiologically relevant forms of Tat (Tat72 and Tat101) in aim 1. This will be followed up in aim 2 by a rationally targeted deletion mutagenesis approach to grossly map the amino acid region in the second exon that provides the added function to the full length protein in regulation of cytokine genes. Finally, in aim 3, the functional region identified by the deletion analysis will be fine mapped by introduction of logically designed individual amino acid substitutions to test the effect on cytokine gene regulation. At the conclusion of this study, we will have significantly advance the field in understanding the molecular requirements of the second exon of Tat to fully mediate host gene regulation. We will be in an opportune position to continue to investigate the pathways by which Tat contributes to HFV-1 pathogenesis because we will have a unique set of tools with which to probe the cellular protein partners that contact the functional element within the Tat second exon. It is our long range goal to use these tools to investigate the biological role and significance of the Tat protein on HIV-1 associated pathologies, particularly HIVD.