School of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan, 411104, Hunan, China.
College of Materials Science and Engineering, Changsha University of Science & Technology, Changsha, 410114, Hunan, China.
Anal Bioanal Chem. 2022 Aug;414(20):6167-6175. doi: 10.1007/s00216-022-04183-4. Epub 2022 Jun 29.
The accurate and sensitive detection of survivin mRNA is of great significance for cancer diagnosis and treatment. However, limited by the low-abundance mRNA in live cells, most strategies of survivin mRNA detection that were one-to-one signal-triggered model (one target triggered one signal) were inapplicable in practice. Here, we reported a binding-induced DNAzyme motor triggered by the survivin mRNA, which was a one-to-more signal-triggered model (one target triggered more signals), amplifying the detection signal and enhancing the sensitivity. The nanomotor is constructed by assembling several DNAzyme motor strands silenced by the blocker strands, and dozens of FAM-labeled substrate strands on a single gold nanoparticle (AuNP), forming three-dimensional DNA tracks. Through building the survivin mRNA bridge between the blocker and the DNAzyme motor strand, the binding-induced DNA nanomotor could be triggered by survivin mRNA. The operation of the DNAzyme motor was self-powered. And each walking step of the DNAzyme motor was fueled by DNAzyme-catalyzed substrate cleavage, along with the cleavage of the fluorescent molecule, resulting in autonomous and progressive walking along the AuNP-based tracks, and the fluorescence increase. The DNAzyme motor exhibited excellent sensitivity and remarkable specificity for survivin mRNA, providing the potential for cell image.
准确灵敏地检测存活素 mRNA 对于癌症的诊断和治疗具有重要意义。然而，由于活细胞中低丰度的 mRNA，大多数存活素 mRNA 检测的策略，即一对一信号触发模型（一个靶标触发一个信号）在实践中并不适用。在这里，我们报道了一种由存活素 mRNA 触发的结合诱导 DNA 酶马达，这是一种一对多信号触发模型（一个靶标触发多个信号），可以放大检测信号并提高灵敏度。纳米马达由几个被阻断链沉默的 DNA 酶马达链组装而成，并在单个金纳米颗粒（AuNP）上组装数十个 FAM 标记的底物链，形成三维 DNA 轨道。通过在阻断链和 DNA 酶马达链之间构建存活素 mRNA 桥，可以由存活素 mRNA 触发结合诱导的 DNA 纳米马达。DNA 酶马达的运行是自供电的。并且，DNA 酶马达的每一步行走都由 DNA 酶催化的底物切割提供动力，伴随着荧光分子的切割，从而沿着基于 AuNP 的轨道自主且连续地行走，并增加荧光。该 DNA 酶马达对存活素 mRNA 具有优异的灵敏度和显著的特异性，为细胞成像提供了潜力。
