Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
Institute of Advanced Materials, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.
Angew Chem Int Ed Engl. 2017 Feb 6;56(7):1855-1858. doi: 10.1002/anie.201611777. Epub 2017 Jan 12.
DNA-based machines have attracted rapidly growing interest owing to their potential in drug delivery, biocomputing, and diagnostic applications. Herein, we report a type of exonuclease III (Exo III)-powered stochastic DNA walker that can autonomously move on a spherical nucleic acid (SNA)-based 3D track. The motion is propelled by unidirectional Exo III digestion of hybridized DNA tracks in a burnt-bridge mechanism. The operation of this Exo III-propelled DNA walker was monitored in real time and at the single-particle resolution using total internal reflection fluorescence microscopy (TIRF). We further interrogated the morphological effect of the 3D track on the nuclease activity, which suggested that the performance of the DNA walker was critically dependent upon the DNA density and the track conformation. Finally, we demonstrated potential bioanalytical applications of this SNA-based stochastic DNA walker by exploiting movement-triggered cascade signal amplification.
基于 DNA 的机器由于在药物输送、生物计算和诊断应用方面的潜力而引起了人们越来越大的兴趣。在此，我们报告了一种外切酶 III（Exo III）驱动的随机 DNA walker，它可以在基于球形核酸（SNA）的 3D 轨道上自主移动。这种运动是通过在烧桥机制中外切酶 III 对杂交 DNA 轨道的单向消化来推动的。使用全内反射荧光显微镜（TIRF）实时和单粒子分辨率监测了这种 Exo III 驱动的 DNA walker 的操作。我们进一步研究了 3D 轨道对核酸酶活性的形态影响，这表明 DNA walker 的性能严重依赖于 DNA 密度和轨道构象。最后，我们通过利用运动触发的级联信号放大，展示了这种基于 SNA 的随机 DNA walker 的潜在生物分析应用。
