The roles of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in cells are closely related. However, the absence of molecular tools for simultaneous imaging of the two nucleic acids has prevented scientists from elucidating the regulatory mechanisms of nucleic acid interaction. The nucleic acid probes developed in recent years have ignored the regulatory relationship between DNA and RNA. Simultaneously imaging RNA and DNA in cells through a single small-molecule fluorescent probe is important. In this study, we propose a strategy for developing fluorescent probes localized to DNA and RNA to investigate their detection and imaging characteristics. The novel probe Bptp-RD has been successfully used for DNA and RNA imaging in cells. We investigated the detection and imaging characteristics of this nucleic acid probe and discovered the following: 1) the differences in the detection results of this nucleic acid probe for DNA and RNA come from the structural differences of the nucleic acids rather than chemical composition differences; 2) through using small-molecule probes to image a nucleic acid in cells, another nucleic acid can be visualized by reducing the fluorescence signal caused by DNA or RNA; 3) the order of response of the small-molecule fluorescent probe with intercalation and binding mechanisms to the type of nucleic acid structure is single chain, double chain, and ring. This work will help improve the understanding of RNA and DNA probes, and the novel probe has high potential to explore the interaction between RNA and DNA in cells.

脱氧核糖核酸（DNA）和核糖核酸（RNA）在细胞中的作用密切相关。然而，由于缺乏对两种核酸同时成像的分子工具，科学家们无法阐明核酸相互作用的调节机制。近年来发展的核酸探针忽略了DNA和RNA之间的调控关系。通过单个小分子荧光探针对细胞中的 RNA 和 DNA 同时成像非常重要。在这项研究中，我们提出了一种开发定位于 DNA 和 RNA 的荧光探针的策略，以研究它们的检测和成像特性。新型探针Bptp-RD已成功用于细胞中的 DNA 和 RNA 成像。我们对该核酸探针的检测和成像特性进行了研究，发现：1）该核酸探针对DNA和RNA的检测结果的差异来自于核酸结构的差异，而不是化学成分的差异；2)通过使用小分子探针对细胞内的一种核酸进行成像，可以通过减少DNA或RNA引起的荧光信号来可视化另一种核酸；3)具有嵌入结合机制的小分子荧光探针对核酸结构类型的响应顺序为单链、双链、环。这项工作将有助于提高对RNA和DNA探针的理解，并且新型探针在探索细胞中RNA和DNA之间的相互作用方面具有很大潜力。