HIV-RNA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在复制过程中，HIV-1病毒从包含大量细胞和剪接病毒RNA的细胞池中选择性地包装两个拷贝的全长未剪接RNA基因组。了解基因组包装机制对于开发新的抗艾滋病策略至关重要。对病毒RNA基因组片段的高分辨率结构研究可以为解开其机制提供有价值的信息。最近的体内研究表明，HIV-15的全长非翻译区(UTR)和Gag基因的上游编码区负责有效的基因组包装。然而，大分子尺寸(~3000 kDa)由于共振重叠和峰展宽，给核磁共振表征带来了极大的困难。为了降低光谱的复杂性，我们使用分段同位素标记的RNA样本来研究完整的352个核苷酸HIV-1 5？-UTR结构。如果低温EM能为这个大的RNA提供一些结构约束，这将是必不可少的。此外，我们期待冷冻-EM可以“可视化”5‘-UTR在二聚时的构象变化。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. During the replication process, HIV-1 viruses selectively package two copies of their full-length unspliced RNA genomes from a cellular pool that contains a substantial excess of cellular and spliced viral RNAs. Understanding the genome packaging mechanism will be essential for the development of new anti-AIDS strategies. High-resolution structural studies of the viral RNA genome fragment can provide valuable information in unraveling the mechanism. Recent in vivo studies have indicated that the full length HIV-1 5¿-untranslated region (UTR) and upstream coding regions of the gag gene are responsible for efficient genome packaging. However, the large molecular size (~3000 kDa) has posed extreme difficulties for NMR characterizations due to the resonance overlap and peak broadening. To reduce the complexity of spectra, we employed segmental isotope labeled RNA samples to investigate the intact 352 nucleotide HIV-1 5¿-UTR structure. It will be essential if cryo-EM can provide some structural constraints for this large RNA. In addition, we are expecting that cryo-EM can "visualize" the 5'-UTR conformation change upon dimerization.