The execution of functions on DNA relies on complex interactions between DNA and proteins in a sequence and structure dependent manner. Accurate quantification of the affinity and kinetics of these interactions is critical for understanding the molecular mechanisms underlying their corresponding biological functions. The development of single-molecule manipulation technologies in the last two decades has made it possible to apply a mechanical constraint to a single DNA molecule and measure the end-to-end extension changes with nanometer resolution in realtime. While it has been shown that such technologies can be used to investigate binding of ligands, which can be proteins or other molecules, to DNA in a fluorescence-label free manner, a systematic review on such applications has been lacking. Here, we provide a review on some of recently developed methods for fluorescence-label free single-molecule quantification of site-specific DNA binding by ligands and demonstrate their wide scope of applications using several examples of binding of ligands to dsDNA and ssDNA binding sites.

中文翻译：

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位点特异性DNA结合的单分子操作定量。

DNA上功能的执行依赖于DNA和蛋白质之间以序列和结构相关的方式进行复杂的相互作用。这些相互作用的亲和力和动力学的准确定量对于理解其相应生物学功能的分子机制至关重要。在过去的二十年中，单分子操纵技术的发展使得可以对单个DNA分子施加机械约束，并以纳米分辨率实时测量端到端延伸的变化。尽管已经显示出这种技术可用于研究配体（可以是蛋白质或其他分子）以无荧光标记的方式与DNA结合，但仍缺乏对此类应用的系统评价。这里，