Engelman A, Mizuuchi K, Craigie R
Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892.
Cell. 1991 Dec 20;67(6):1211-21. doi: 10.1016/0092-8674(91)90297-c.
Retroviral DNA integration involves a coordinated set of DNA cutting and joining reactions. Linear viral DNA is cleaved at each 3' end to generate the precursor ends for integration. The resulting recessed 3' ends are inserted into target DNA by a subsequent DNA strand transfer reaction. Purified HIV-1 integration protein carries out both of these steps in vitro. Two novel forms of the dinucleotide cleaved from HIV-1 DNA were identified and one, a cyclic dinucleotide, was used to analyze the stereochemical course of viral DNA cleavage. Both viral DNA cleavage and DNA strand transfer display inversion at chiral phosphorothioates during the course of the reaction. These results suggest that both reactions occur by a one-step mechanism without involvement of a covalent protein-DNA intermediate.
逆转录病毒DNA整合涉及一系列协调的DNA切割和连接反应。线性病毒DNA在每个3'端被切割，以产生用于整合的前体末端。随后通过DNA链转移反应将产生的凹陷3'端插入靶DNA中。纯化的HIV-1整合蛋白在体外执行这两个步骤。鉴定出从HIV-1 DNA切割的两种新型二核苷酸形式，其中一种环状二核苷酸用于分析病毒DNA切割的立体化学过程。在反应过程中，病毒DNA切割和DNA链转移在手性硫代磷酸酯处均显示出反转。这些结果表明，这两种反应均通过一步机制发生，而无需共价蛋白-DNA中间体的参与。
