Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Materials Science, Key Laboratory of Resource Biology and Biotechnology in Western China of the Ministry of Education , Northwest University , Xi'an 710127 , P. R. China.
Department of Chemistry , Zhejiang University , Hangzhou 310058 , P. R. China.
Anal Chem. 2019 Apr 16;91(8):5354-5361. doi: 10.1021/acs.analchem.9b00436. Epub 2019 Mar 29.
DNA G-quadruplexes (G4s) in vivo have been linked to cancer and other diseases such as neurological disorders. Nondestructive fast detection of endogenous DNA G4s can provide specific real-time information, which is of particular interest for clinic accurate diagnosis. However, tools to probe live-cell endogenous DNA G4s in real time are very limited. Herein, we report the design and development of a fluorescent molecule QIN for the real-time detection of endogenous DNA G4s in live cells with the aid of a new spiropyran in situ switching (SIS) strategy. The lipophilic spiropyran-linked QIN differs from the other probes in that it can enter live cells readily within 15 s and can be in situ induced by DNA G4s to adopt its charged open form, causing a large red shift in the fluorescent emission wavelength. Live-cell super-resolution fluorescent imaging suggests that the SIS-based probe has high photostability and can be applied for the accurate detection of DNA G4s in complex biosystems with very high sensitivity and selectivity.
DNA 四链体（G4s）在体内与癌症和其他疾病（如神经紊乱）有关。内源性 DNA G4s 的非破坏性快速检测可以提供特定的实时信息，这对于临床准确诊断特别有意义。然而，用于实时探测活细胞内源性 DNA G4s 的工具非常有限。在此，我们报告了一种荧光分子 QIN 的设计和开发，该分子借助新的螺吡喃原位转换（SIS）策略，用于实时检测活细胞内的内源性 DNA G4s。与其他探针不同，连接脂溶性螺吡喃的 QIN 可以在 15 秒内轻易进入活细胞，并可被 DNA G4s 原位诱导，采用其带电的开环形式，导致荧光发射波长发生大的红移。活细胞超分辨率荧光成像表明，基于 SIS 的探针具有高的光稳定性，并且可以非常高的灵敏度和选择性应用于复杂生物体系中 DNA G4s 的准确检测。
