Lv Mengmeng, Ren Jiangtao, Wang Erkang
College of Chemistry, Jilin University Changchun Jilin 130012 China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
Chem Sci. 2024 Feb 9;15(12):4519-4528. doi: 10.1039/d3sc06862e. eCollection 2024 Mar 20.
In this work, the topological effect on binding interaction between a G-quadruplex and thioflavin T (ThT) ligand was systematically investigated on a platform of an intramolecular split G-quadruplex (Intra-SG). Distinct fluorescence changes from ThT were presented in the presence of distinct split modes of Intra-SG structures and an intriguing phenomenon of target-induced fluorescence light-up occurred for split modes 2 : 10, 5 : 7 and 8 : 4. It was validated that hybridization between the Intra-SG spacer and target did not unfold the G-quadruplex, but facilitated the ThT binding. Moreover, the 3' guanine-rich fragment of Intra-SG was very susceptible to topology variation produced by the bound target strand. Additionally, a bioanalytical method was developed for ultrasensitive gene detection, confirming the utility of the ThT/Intra-SG complex as a universal signal transducer. It is believed that the results and disclosed rules will inspire researchers to develop many new DNA-based signal transducers in the future.
在本研究中，在分子内分裂型G-四链体（Intra-SG）平台上系统研究了拓扑结构对G-四链体与硫黄素T（ThT）配体之间结合相互作用的影响。在不同的Intra-SG结构分裂模式下，ThT呈现出不同的荧光变化，并且在2 : 10、5 : 7和8 : 4的分裂模式下出现了有趣的靶标诱导荧光点亮现象。经证实，Intra-SG间隔区与靶标之间的杂交并未使G-四链体解折叠，而是促进了ThT的结合。此外，Intra-SG富含鸟嘌呤的3'片段对结合的靶标链产生的拓扑结构变化非常敏感。另外，开发了一种用于超灵敏基因检测的生物分析方法，证实了ThT/Intra-SG复合物作为通用信号转导器的实用性。相信这些结果和所揭示的规律将激励研究人员在未来开发许多新型基于DNA的信号转导器。
