Gadelle Danièle, Filée Jonathan, Buhler Cyril, Forterre Patrick
Institut de Génétique et Microbiologie, CNRS, UMR 8621, Université Paris-Sud, France.
Bioessays. 2003 Mar;25(3):232-42. doi: 10.1002/bies.10245.
Type II DNA topoisomerases (Topo II) are essential enzymes implicated in key nuclear processes. The recent discovery of a novel kind of Topo II (DNA topoisomerase VI) in Archaea led to a division of these enzymes into two non-homologous families, (Topo IIA and Topo IIB) and to the identification of the eukaryotic protein that initiates meiotic recombination, Spo11. In the present report, we have updated the distribution of all Topo II in the three domains of life by a phylogenomic approach. Both families exhibit an atypical distribution by comparison with other informational proteins, with predominance of Topo IIA in Bacteria, Eukarya and viruses, and Topo IIB in Archaea. However, plants and some Archaea contain Topo II from both families. We confront this atypical distribution with current hypotheses on the evolution of the three domains of life and origin of DNA genomes.
II型DNA拓扑异构酶（Topo II）是参与关键核过程的必需酶。最近在古细菌中发现了一种新型的Topo II（DNA拓扑异构酶VI），这导致这些酶被分为两个非同源家族（Topo IIA和Topo IIB），并鉴定出了启动减数分裂重组的真核蛋白Spo11。在本报告中，我们通过系统基因组学方法更新了所有Topo II在生命三个域中的分布。与其他信息蛋白相比，这两个家族都呈现出非典型分布，Topo IIA在细菌、真核生物和病毒中占主导地位，而Topo IIB在古细菌中占主导地位。然而，植物和一些古细菌同时含有这两个家族的Topo II。我们将这种非典型分布与当前关于生命三个域的进化以及DNA基因组起源的假设进行了对比。
