Single-molecule orientation measurements provide unparalleled insight into a multitude of biological and polymeric systems. We report a simple, high-throughput technique for measuring the azimuthal orientation and rotational dynamics of single fluorescent molecules, which is compatible with localization microscopy. Our method involves modulating the polarization of an excitation laser, and analyzing the corresponding intensities emitted by single dye molecules and their modulation amplitudes. To demonstrate our approach, we use intercalating and groove-binding dyes to obtain super-resolved images of stretched DNA strands through binding-induced turn-on of fluorescence. By combining our image data with thousands of dye molecule orientation measurements, we develop a means of probing the structure of individual DNA strands, while also characterizing dye-DNA interactions. This approach may hold promise as a method for monitoring DNA conformation changes resulting from DNA-binding proteins.

中文翻译：

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使用超分辨率显微镜和同步单分子方向测量增强 DNA 成像。

单分子取向测量为众多生物和聚合物系统提供了无与伦比的洞察力。我们报告了一种简单、高通量的技术，用于测量单个荧光分子的方位角方向和旋转动力学，该技术与定位显微镜兼容。我们的方法涉及调制激发激光的偏振，并分析单个染料分子发射的相应强度及其调制幅度。为了演示我们的方法，我们使用嵌入和凹槽结合染料通过结合诱导的荧光开启来获得拉伸 DNA 链的超分辨图像。通过将图像数据与数千个染料分子方向测量相结合，我们开发了一种探测单个 DNA 链结构的方法，同时还表征了染料与 DNA 相互作用。这种方法有望成为监测 DNA 结合蛋白引起的 DNA 构象变化的方法。