Structural studies of DNA-processing enzymes

 描述(申请人提供)：我们将使用结构生物学工具来研究人类病原体的DNA加工酶，以及那些与基因组完整性或疾病过程相关的酶。一个特别感兴趣的领域是病毒整合酶(IN)整合逆转录病毒的机制，它与线性病毒DNA基因组的两端形成多聚体复合体，并捕获细胞靶DNA，以协调病毒DNA末端的插入。由HIV-1 IN形成的IN-病毒DNA复合体是一类名为IN链转移抑制剂的抗病毒药物的靶标。因此，更好地了解IN与DNA的相互作用对于改进临床上使用的IN抑制剂以及设计下一代抑制剂具有重要意义。我们正在寻找HIV-1和密切相关的逆转录病毒的IN-DNA复合体的晶体结构，以及那些与宿主辅助因子LEDGF/p75形成的复合体的结构。我们的初步数据表明，包含病毒和靶DNA分子的多聚体IN复合体的结构在广泛表征的泡沫病毒原型和其他具有较小3结构域INS的逆转录病毒中是不同的，包括Rous肉瘤病毒和HIV-1。除了逆转录病毒INS，我们还对细菌和痘病毒酶感兴趣，这些细菌和痘病毒酶负责通过分解串联复制中间体来再生线性染色体的发夹端粒。我们还研究了参与清理受损DNA末端的酶，以通过末端连接实现无错误修复。通过对这些系统的研究，我们打算学习DNA-蛋白质相互作用的新原理，并获得有助于抑制物开发或设计有用的工程化酶的结构信息。

 DESCRIPTION (provided by applicant): We will use structural biology tools to investigate DNA-processing enzymes from human pathogens, and those relevant to genome integrity or disease process. An area of particular interest is the mechanism of retrovirus integration by the viral integrase (IN), which forms a multimeric complex with both ends of the linear viral DNA genome and captures a cellular target DNA for concerted insertions of the viral DNA termini. The IN-viral DNA complex formed by HIV-1 IN is the target of a class of antiviral drugs called IN strand-transfer inhibitors. Therefore, a better understanding of the IN-DNA interactions is important for improving the clinically used IN inhibitors as well as designing next-generation inhibitors. We are pursuing crystal structures of IN-DNA complexes from HIV-1 and closely related retroviruses, and structure of those in complex with the host co- factor LEDGF/p75. Our preliminary data suggest that the architectures of the multimeric IN complex containing viral and target DNA molecules are distinct between the extensively characterized prototype foamy virus and other retroviruses with smaller 3-domain INs, including Rous sarcoma virus and HIV-1. Besides retrovirus INs, we are interested in the bacterial and pox viral enzymes responsible for regenerating the hairpin telomeres of linear chromosomes by resolving concatemeric replication intermediates. We also study enzymes involved in cleaning damaged DNA ends for error-free repair by end-joining. Through studies of these systems, we intend to learn novel principles in DNA-protein interactions and obtain structural information that can aid in inhibitor development or design of useful engineered enzymes.