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Published on: November 10, 2016
Topoisomerase I-mediated DNA relaxation as a tool to study intercalation of small molecules into supercoiled DNA
Paul Peixoto1, Christian Bailly, Marie-Hélène David-Cordonnier
1INSERM U-837, Jean-Pierre Aubert Research Center (JPARC), Institut de Recherches sur le Cancer de Lille, Lille, France.
Abstract:
Several biochemical and biophysical methods are available to study the intercalation of a small molecule between two consecutive base pairs of DNA. Among them, the topoisomerase I-mediated DNA relaxation assay has proved highly efficient, relatively easy to handle and very informative to investigate drug binding to DNA. The test relies on the use of a supercoiled plasmid to mimic the topological constraints of genomic DNA. The three main components of the assay - the topoisomerase I enzyme, DNA helix and intercalating small molecules - are presented here in a structural context. The principle of the assay is described in detail, along with a typical experimental protocol.
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