Angular Optical Trapping to Directly Measure DNA Torsional Mechanics.
Angular Optical Trapping to Directly Measure DNA Torsional Mechanics.
复制标题
角度光学捕获直接测量 DNA 扭转力学。
DOI：
10.1007/978-1-0716-2229-2_4
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Wang,MichelleD
中科院分区：
文献类型：
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作者：
Gao,Xiang;Inman,JamesT;Wang,MichelleD
角光学捕获（AOT）是一种强大的技术，它允许对捕获的粒子进行直接的角操作，同时测量扭矩和旋转，同时还保留了位置和力检测的能力。该技术提供了独特的方法来研究核酸和DNA-蛋白质复合物的扭转特性，以及扭转应力对基本生物过程（如转录和复制）的影响。在这里，我们详细描述了AOT的原理、构造和校准，并为DNA分子上的单分子扭矩测量的性能提供了指导。我们包括恒定力的方法，特别是，一个新的恒定的延伸方法，使测量的扭曲持久性长度的两个扩展的DNA，在一个非常低的力，和plectonemic DNA。本章可以帮助一般研究人员在单分子领域的实施和应用这项技术。
Angular optical trapping (AOT) is a powerful technique that permits direct angular manipulation of a trapped particle with simultaneous measurement of torque and rotation, while also retaining the capabilities of position and force detection. This technique provides unique approaches to investigate the torsional properties of nucleic acids and DNA-protein complexes, as well as impacts of torsional stress on fundamental biological processes, such as transcription and replication. Here we describe the principle, construction, and calibration of the AOT in detail and provide a guide to the performance of single-molecule torque measurements on DNA molecules. We include the constant-force method and, notably, a new constant-extension method that enables measurement of the twist persistence length of both extended DNA, under an extremely low force, and plectonemic DNA. This chapter can assist in the implementation and application of this technique for general researchers in the single-molecule field.