Functional Variation of Rev and RRE Activity During HIV Infection

描述（由申请人提供）：本提案探讨了感染期间患者体内不同Rev/RRE活动演变的基础，并阐述了RRE结构如何调节Rev功能。它还检查了Rev/RRE功能的调节是否在两种不同的临床情况下发挥作用。通过单基因组测序获得的最新数据表明，受感染个体的Rev和RRE活性随着HIV的演变而变化，并且这种变化仅由Rev或RRE序列的少量变化引起。Rev/RRE活性的这种变化可以深刻地影响病毒复制的速度。数据还表明，任何特定的Rev序列与不同的RRE配对都会导致Rev/RRE总体活性水平的显著变化。这强调了分析Rev和RRE作为同源对来自同一病毒基因组的重要性。目前，对于Rev或RRE序列的微小变化如何调节它们的联合活性，还没有机制上的理解。本提案的目的之一就是解决这个问题。我们最近也获得了数据，证明RRE是一个动态的RNA结构。特别是茎环区III和IV既可以作为一个茎环存在，也可以作为两个独立的茎环存在，这两个结构可能处于平衡状态。我们的数据表明，具有单个茎环IV的结构的形成对Rev和RRE功能至关重要。另一个目的是研究这一现象的机制基础。最后，我们还将进一步探讨良好的免疫控制选择Rev/RRE活性较低的病毒的假设。此外，我们还将研究具有较低Rev/RRE活性的病毒是否有利于建立潜伏感染细胞。具体目标：具体目标#1：茎环III/IV RRE序列重排的功能意义是什么？特定目标#2：从感染患者中提取的特定Rev- RRE对观察到的活性差异的基础是什么？具体目标3：分析两种不同临床情况下Rev-RRE的活性。

DESCRIPTION (provided by applicant): This proposal explores the basis for the different Rev/RRE activities that evolve in patients during infection, and also addresses how the structure of the RRE regulates Rev function. It also examines if the modulation of Rev/RRE function plays a role in two different clinical scenarios. Recent data, obtained by single genome sequencing, show that both Rev and RRE activity in an infected individual vary as HIV evolves, and that this variation arises from only a few changes in either Rev or RRE sequence. This change in Rev/RRE activity can profoundly affect rates of viral replication. The data also show that the pairing of any particular Rev sequence with different RREs leads to significant changes in overall Rev/RRE activity levels. This emphasizes the importance of analyzing Rev and RRE as a cognate pair derived from the same viral genome. At the present time, there is no mechanistic understanding of how small changes in sequence of either Rev or RRE modulate their combined activity. One of the aims of this proposal addresses this issue. We have also recently obtained data that demonstrate that the RRE is a dynamic RNA structure. In particular, stem loop regions III and IV can exist either as a single stem loop or as two separate ones, and the two structures probably are in equilibrium. Our data suggest that the formation of the structure with the individual stem loop IV is critical for Rev and RRE function. Another aim will examine the mechanistic basis for this. In the last aim, we will also further explore the hypothesis that good immune control selects for viruses with lower Rev/RRE activity. In addition we will also examine if viruses with lower Rev/RRE activity are favored in establishment of latently infected cells. The specific aims are: Specific Aim #1: What is the functional significance of the stem loop III/IV RRE sequence rearrangement? Specific Aim #2: What is the basis for the differences in activity that are observed with selected Rev- RRE pairs derived from infected patients? Specific Aim #3: Analysis of Rev-RRE activity in two different clinical scenarios.