Department of Physics, Emory University, Atlanta, GA, USA.
Methods Mol Biol. 2024;2694:451-466. doi: 10.1007/978-1-0716-3377-9_21.
The range of motion of a micron-sized bead tethered by a single polymer provides a dynamic readout of the effective length of the polymer. The excursions of the bead may reflect the intrinsic flexibility and/or topology of the polymer as well as changes due to the action activity of ligands that bind the polymer. This is a simple yet powerful experimental approach to investigate such interactions between DNA and proteins as demonstrated by experiments with the lac repressor. This protein forms a stable, tetrameric oligomer with two binding sites and can produce a loop of DNA between recognition sites separated along the length of a DNA molecule.
通过单个聚合物连接的微米级珠子的运动范围为聚合物的有效长度提供了动态读数。珠子的运动可能反映了聚合物的固有柔韧性和/或拓扑结构，以及由于与聚合物结合的配体的作用而发生的变化。正如与 lac 阻遏物的实验所证明的那样，这是一种简单而强大的实验方法，可以研究 DNA 和蛋白质之间的这种相互作用。该蛋白质与两个结合位点形成稳定的四聚体寡聚体，并且可以在沿着 DNA 分子的长度分离的识别位点之间产生 DNA 环。
