Laboratory of Molecular Biophysics, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA.
J Biol Chem. 2010 Jun 18;285(25):18967-71. doi: 10.1074/jbc.R109.092437. Epub 2010 Apr 9.
Topological properties of DNA influence its mechanical and biochemical interactions. Genomic DNA is maintained in a state of topological homeostasis by topoisomerases and is subjected to mechanical stress arising from replication and segregation. Despite their fundamental roles, the effects of topology and force have been difficult to ascertain. Developments in single-molecule manipulation techniques have enabled precise control and measurement of the topology of individual DNA molecules under tension. This minireview provides an overview of these single-molecule techniques and illustrates their unique capabilities through a number of specific examples of single-molecule measurements of DNA topology and topoisomerase activity.
DNA 的拓扑性质影响其机械和生化相互作用。拓扑异构酶维持基因组 DNA 的拓扑动态平衡,并承受复制和分离产生的机械应力。尽管拓扑和力具有重要作用,但它们的影响很难确定。单分子操作技术的发展使得在张力下对单个 DNA 分子的拓扑结构进行精确控制和测量成为可能。这篇综述概述了这些单分子技术,并通过一些单分子测量 DNA 拓扑和拓扑异构酶活性的具体实例来说明它们的独特功能。