Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, P. R. China.
J Mater Chem B. 2019 Mar 21;7(11):1926-1932. doi: 10.1039/c9tb00001a. Epub 2019 Feb 15.
Telomerase catalyzes the elongation of telomeres, which is closely associated with tumorigenesis. Therefore, development of reliable and convenient methods for telomerase activity analysis is critical for clinical diagnosis of cancers. However, most of the current probes for intracellular telomerase activity assay suffer from inevitable false-positive interferences. In this study, we have proposed a novel fluorescence resonance energy transfer (FRET)-based strategy for ultrasensitive monitoring intracellular telomerase activity with an amplification-free procedure. DNA nanoprobes constructed using a DNA tetrahedron and Flare DNA are designed to circumvent the problem of false-positive interference. Generally, telomerase catalyzes DNA extension and changes the configuration of the DNA nanoprobe, which finally leads to the increase of the distance between two labelled fluorophores. Based on the notably decreased FRET efficiency, a simple ratiometric sensor is established for the detection of telomerase activity at the single-cell level, which is much suitable for clinical applications. In addition, this method can be further applied in the detection of telomerase inhibitors, which is important for anti-cancer drug discovery.
端粒酶催化端粒的延伸，这与肿瘤发生密切相关。因此，开发可靠和方便的端粒酶活性分析方法对于癌症的临床诊断至关重要。然而，目前大多数用于细胞内端粒酶活性测定的探针都存在不可避免的假阳性干扰。在这项研究中，我们提出了一种基于荧光共振能量转移（FRET）的新策略，用于在无扩增的过程中超灵敏地监测细胞内端粒酶活性。使用 DNA 四面体和 Flare DNA 构建的 DNA 纳米探针被设计用来规避假阳性干扰的问题。通常，端粒酶催化 DNA 延伸并改变 DNA 纳米探针的构型，最终导致两个标记荧光团之间的距离增加。基于明显降低的 FRET 效率，建立了一种简单的比率传感器，用于在单细胞水平检测端粒酶活性，这非常适合临床应用。此外，该方法可进一步应用于端粒酶抑制剂的检测，这对于抗癌药物的发现很重要。
