Seol Yeonee, Neuman Keir C
Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
Methods Mol Biol. 2011;783:265-93. doi: 10.1007/978-1-61779-282-3_15.
Magnetic tweezers provide a versatile tool enabling the application of force and torque on individual biomolecules. Magnetic tweezers are uniquely suited to the study of DNA topology and protein-DNA interactions that modify DNA topology. Perhaps due to its presumed simplicity, magnetic tweezers instrumentation has been described in less detail than comparable techniques. Here, we provide a comprehensive description and guide for the design and implementation of a magnetic tweezers instrument for single-molecule measurements of DNA topology and mechanics. We elucidate magnetic trap design, as well as microscope and illumination setup, and provide a simple LabVIEW-based real-time position tracking algorithm. In addition, we provide procedures for production of supercoilable DNA tethers, flow-cell design, and construction tips.
磁性镊子提供了一种多功能工具，能够对单个生物分子施加力和扭矩。磁性镊子特别适合用于研究DNA拓扑结构以及改变DNA拓扑结构的蛋白质-DNA相互作用。也许是由于其假定的简单性，与其他类似技术相比，对磁性镊子仪器的描述较少。在这里，我们提供了一份关于用于DNA拓扑结构和力学单分子测量的磁性镊子仪器设计与实施的全面描述和指南。我们阐明了磁阱设计以及显微镜和照明设置，并提供了一种基于LabVIEW的简单实时位置跟踪算法。此外，我们还提供了超可卷曲DNA系链的制备程序、流动池设计和构建技巧。
