SMALL ANGLE X-RAY SCATTERING STUDIES OF HIV NUCLEOPROTEIN

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 虽然HIV整合酶的几个片段可在蛋白质数据库中获得，但完整全长整合酶在其催化相关寡聚体状态和整合酶-DNA复合物中的实验结构已经回避了晶体学分析。 本研究的目标是开发这些大分子复合物的实验衍生模型，这对于促进我们对HIV整合及其结构基础的理解至关重要。 持续的艾滋病大流行使得设计有效的药物治疗成为一个至关重要的目标。虽然一些有前途的整合酶抑制剂正在从后期临床试验中出现，但临床使用的大多数可用抑制剂仅针对其他病毒编码的蛋白质。由于病毒cDNA整合到宿主基因组中对逆转录病毒生命周期至关重要，并且由于没有已知的细胞酶在序列或功能上与整合酶非常相似，因此整合酶抑制剂具有相对无毒且非常有效的潜力。 现在清楚的是，与溶液中的游离整合酶相比，正确组装的整合酶复合物对抑制剂具有不同的和更有区别的反应。 因此，复杂的详细结构模型是必不可少的基于结构的药物设计。 利用分析超离心和凝胶过滤，已经完成了由HIV整合酶、整合酶结合蛋白透镜上皮衍生生长因子（LEDGF）和DNA底物形成的复合物的生物物理表征。 在有限的样品浓度范围内，已经在CHESS的Beamline G1上进行了小角X射线散射试验。

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. While several segments of HIV integrase are available in the Protein Data Bank, experimental structures of intact full-length integrase in its catalytically relevant oligomeric states and integrase-DNA complex have eluded crystallographic analysis. The goal of this study is to develop experimentally-derived models of these macromolecular complexes, which is vital to advancing our understanding of HIV integration and its structural basis. The ongoing AIDS pandemic has made the design of effective pharmacological treatments a goal of paramount importance. While some promising integrase inhibitors are emerging from late clinical trials, most available inhibitors in clinical use only target other viral-encoded proteins. Because integration of viral cDNA into the host genome is critical to the retroviral life cycle and since there are no known cellular enzymes that closely resemble integrase in sequence or function, inhibitors of integrase have the potential to be relatively nontoxic and very effective. It is now clear that, in comparison to free integrase in solution, correctly assembled integrase complex has a different and more discriminating response to inhibitors. Hence, a detailed structural model of the complex is essential to structure-based drug design. Biophysical characterization of complexes formed by HIV integrase, the integrase-binding protein Lens Epithelial-Derived Growth Factor (LEDGF), and DNA substrate, using analytical ultracentrifugation and gel filtration, has already been completed. Pilot SAXS experiments at Beamline G1 of CHESS have already been performed at a limited range of sample concentrations.