HIV-1 Integrase Structural Biology

描述（由申请人提供）：与所有逆转录病毒一样，HIV-1必须将逆转录产生的cDNA拷贝整合到细胞染色体中才能复制。HIV-1整合是由必需的病毒酶整合酶催化的。这使得整合酶成为一个有吸引力的药物靶点，抗整合酶化合物正在美国进行临床试验。合理的药物设计受益于三维酶结构的可视化，并且HIV-1整合酶催化核心结构域的许多结构已经被解决。虽然两个结构域的N-末端/核心和核心/C-末端结构也得到解决，但没有完整的整合酶蛋白的结构，这在很大程度上可归因于蛋白质溶解度差。在细胞中，整合酶可能与正常的人类蛋白质相互作用，并且整合酶与转录共激活因子透镜上皮衍生生长因子（LEDGF）之间的相互作用形成了这种应用的基础。我们最近解决了三维结构的整合酶结合结构域（IBD）在LEDGF使用NMR光谱和本文提出的晶体结构的IBD结合到HIV-1整合酶的二聚体核心结构域。从这些结果的建设，我们建议利用LEDGF IBD形成新的LEDGF-IN复合物，并解决全长整合酶蛋白的三维结构。我们的新结构揭示了在核心结构域二聚体界面处的口袋，其在复合物形成后被LEDGF热点残基占据。由于消除与LEDGF相互作用的整合酶突变会杀死HIV-1，因此我们假设与核心区域结合并阻止LEDGF结合的化合物可能会类似地削弱HIV-1。先前的结果表明，某些整合酶抑制剂结合在或接近这个口袋，但这些化合物不抑制LEDGF整合酶的相互作用。将设计一种新的测定系统来选择LEDGF-整合酶相互作用的抑制剂。这些实验的结果将显着帮助HIV-1整合酶功能的抑制剂的设计，作为完整的酶的三维结构将被阐明，并将开发一种检测，可以选择新的HIV-1复制抑制剂。

DESCRIPTION (provided by applicant): Like all retroviruses, HIV-1 must integrate the cDNA copy made by reverse transcription into a cell chromosome in order to replicate. HIV-1 integration is catalyzed by the essential viral enzyme integrase. This makes the integrase an attractive drug target, and anti-integrase compounds are in US clinical trials. Rational drug design benefits from visualizing three-dimensional enzyme structures, and numerous structures of the HIV-1 integrase catalytic core domain have been solved. Although two domain N-terminal/core and core/C-terminal structures are also solved, there is no structure for the intact integrase protein, which in large part can be attributed to poor protein solubility. In cells, integrase is likely to interact with normal human proteins, and the interaction between integrase and the transcriptional co-activator lens epithelium-derived growth factor (LEDGF) forms the basis for this application. We recently solved the three-dimensional structure of the integrase-binding domain (IBD) in LEDGF using NMR spectroscopy and herein present the crystal structure of the IBD bound to the dimeric core domain of HIV-1 integrase. Building from these results, we propose to utilize the LEDGF IBD to form novel LEDGF-IN complexes and to solve the three-dimensional structure of the full-length integrase protein. Our novel structure revealed a pocket at the core domain dimer interface that is occupied by LEDGF hot spot residues upon complex formation. Because integrase mutations that ablate the interaction with LEDGF kill HIV-1, we hypothesize that compounds that bind to this region of the core and preclude LEDGF binding might similarly cripple HIV-1. Previous results revealed that certain integrase inhibitors bind at or near this pocket, but those compounds did not inhibit the LEDGF-integrase interaction. A novel assay system will be designed to select for inhibitors of the LEDGF-integrase interaction. The results of these experiments will significantly aid the design of inhibitors of HIV-1 integrase function, as the three-dimensional structure of the intact enzyme will be elucidated and an assay that could select for novel inhibitors of HIV-1 replication will be developed.