Efficient Intracellular MicroRNA Imaging Based on the Localized and Self-Sustainable Catalytic DNA Assembly Circuit

Buildingdynamic biological networks, especially DNA circuits,has provided a powerful prospect for exploring the intrinsic regulationprocesses of live cells. Nevertheless, for efficient intracellularmicroRNA analysis, the available multi-component circuits are constrainedby their limited operating speed and efficiency due to the free diffusionof reactants. Herein, we developed an accelerated Y-shaped DNA catalytic(YDC) circuit for high-efficiency intracellular imaging of microRNA.By grafting the catalytic hairpin assembly (CHA) reactants into anintegrated Y-shaped scaffold, the CHA probes were concentrated ina compact space, thus achieving high signal amplification. Profitingfrom the spatially confined reaction and the self-sustainably assembledDNA products, the YDC system facilitated reliable and in situ microRNA imaging in live cells. Compared with the homogeneouslydispersed CHA reactants, the integrated YDC system could efficientlypromote the reaction kinetics as well as the uniform delivery of CHAprobes, thus providing a robust and reliable analytical tool for diseasediagnosis and monitoring.

Automated summary

The Y-shaped DNA catalytic circuit is developed to efficiently analyze microRNA in live cells, providing a reliable tool for disease diagnosis and monitoring.