Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , P. R. China.
Key Laboratory of Biomedical Polymers (Ministry of Education), College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , P. R. China.
ACS Sens. 2019 Jan 25;4(1):110-117. doi: 10.1021/acssensors.8b01000. Epub 2019 Jan 2.
Abnormal microRNAs (miRNAs) expression is demonstrated to associate with various important biological processes, including tumorigenesis, metastasis, and progression. Given the low miRNA expression at the earlier stage of diseases, its amplified detection still requires more efforts. Inspired by the two-stage arithmetic amplifier of electric devices, we reported an autonomous and catalytic assembly of DNAzyme strategy by integrating a DNAzyme biocatalyst and catalytic hairpin assembly (CHA) circuit. Here the catalytically inactive DNAzyme subunits were respectively grafted into these metastable CHA hairpin reactants that were kinetically impeded without false cross-hybridizations. The target catalyzed the nonenzymatic CHA-mediated successive assembly of dumbbell-like bis-DNAzyme nanostructures, leading to the efficient DNAzyme-mediated cleavage of fluorophore/quencher-modified substrate and to the generation of an amplified fluorescence signal. The present CHA-DNAzyme amplifier can be employed as a versatile and general sensing platform for analyzing other analytes (e.g., miRNA) by introducing a sensing module into the present system. Moreover, the homogeneous CHA-DNAzyme method could realize the sensitive intracellular miRNA imaging in living cells, which is attributed to the inherently synergistic amplification property between DNAzyme and CHA reactions. Given the attractive analytical features of the autonomous CHA-DNAzyme system, the present strategy shows great promise for analyzing additional different analytes in clinical research fields.
异常的 microRNAs（miRNAs）表达被证明与各种重要的生物学过程有关，包括肿瘤发生、转移和进展。鉴于疾病早期 miRNA 表达水平较低，其扩增检测仍需要更多的努力。受电设备两级运算放大器的启发，我们通过整合 DNA 酶生物催化剂和催化发夹组装（CHA）电路，报道了一种自主和催化组装 DNA 酶的策略。在这里，无活性的 DNA 酶亚基分别被嫁接在这些亚稳定的 CHA 发夹反应物上，这些反应物由于动力学受阻而不会发生错误的交叉杂交。靶标催化非酶促 CHA 介导的哑铃状双 DNA 酶纳米结构的连续组装，导致荧光团/猝灭剂修饰底物的有效 DNA 酶介导切割，并产生放大的荧光信号。本 CHA-DNA 酶放大器可通过在本系统中引入传感模块，作为分析其他分析物（例如 miRNA）的通用和通用传感平台。此外，均相 CHA-DNA 酶方法可以实现活细胞内敏感的细胞内 miRNA 成像，这归因于 DNA 酶和 CHA 反应之间固有的协同放大特性。鉴于自主 CHA-DNA 酶系统的诱人分析特性，本策略有望在临床研究领域分析更多不同的分析物。
