Pognan F, Paoletti C
Laboratoire de Biochimie-Enzymologie, URA 147, Institut Gustave-Roussy, Villejuif, France.
Biochimie. 1992 Nov;74(11):1019-23. doi: 10.1016/0300-9084(92)90022-7.
Topoisomerase II displays higher affinity for supercoiled DNA compared to the same relaxed DNA. Moreover, cruciform structures are formed in topologically constrained DNA. Here we report that, using S1 nuclease experiments on supercoiled DNA, hairpin structures are located close to numerous topoisomerase II cleavage sites on the BPV I genome. Therefore, DNA secondary structure may play a role in the recognition mechanism of DNA by topoisomerase II.
与相同的松弛DNA相比，拓扑异构酶II对超螺旋DNA显示出更高的亲和力。此外，在拓扑受限的DNA中会形成十字形结构。在此我们报告，通过对超螺旋DNA进行S1核酸酶实验，发现在BPV I基因组上，发夹结构位于众多拓扑异构酶II切割位点附近。因此，DNA二级结构可能在拓扑异构酶II识别DNA的机制中发挥作用。
