Rational Engineering of a Dynamic, Entropy‐Driven DNA Nanomachine for Intracellular MicroRNA Imaging

Abstract

We rationally engineered an elegant entropy-driven DNAn anomachine with three-dimensional tracka nd applied it for intracellular miRNAs imaging.T he proposed nanomachine is activated by target miRNAb inding to drive awalking leg tethered to gold nanoparticle with ahigh density of DNAsubstrates.The autonomous and progressive walk on the DNAt rack via the entropy-driven catalytic reaction of intramolecular toehold-mediated strand migration leads to continuous disassembly of DNAs ubstrates,a ccompanied by the recovery of fluorescence signal due to the specific release of ad ye-labeled substrate from DNAt rack. Our nanomachine outperforms the conventional intermolecular reaction-based gold nanoparticle design in the context of an improved sensitivity and kinetics,a ttributed to the enhanced local effective concentrations of working DNAc omponents from the proximity-induced intramolecular reaction. Moreover,t he nanomachine was applied for miRNAi maging inside living cells.

Novel Biosensing Strategies for the in Vivo Detection of microRNA

“…Liang et al [40] constructed an entropy-driven DNA nanomachine. A threestranded substrate complex (A/B/C) and an affinity ligand (L) were modified on the AuNP surface, respectively.…”

Next-Generation DNA-Functionalized Quantum Dots as Biological Sensors

“…This strategy was later adopted by different research groups for sensitive imaging of miRNA in living cells. 96,97 Additionally, other DNA-based signal amplification strategies such as DNAzyme and the hybridization chain reaction were applied for miRNA imaging in living cells. 98,99 While most of these strategies utilize organic fluorophores as reporters, integration of II-G DNA-QDs into these systems could potentially offer stronger and persistent fluorescence signals to improve detection sensitivity and enable long-term imaging.…”

Construction of a Homogeneous Enzyme-Free Autocatalytic Nucleic Acid Machinery for High-Performance Intracellular Imaging of MicroRNA

“…Dynamic DNA nanotechnology has emerged as a powerful tool for programming the assembly of diverse and ingenious DNA nanostructures through the autonomously successive hybridization-based strategies, [1][2][3] including hybridization chain reaction (HCR), [4][5][6][7][8][9] entropy-driven catalysis, [10][11][12] and catalyzed hairpin assembly. [13][14][15] HCR represents a general principle to initiate the autonomous cross-opening or polymerization of two hairpin reactants to generate long dsDNA copolymers upon the introduction of triggering nucleic acids or small molecules.…”