We report here the concept of a self-powered, target-triggered DNA motor constructed by engineering a DNAzyme to adapt into binding-induced DNA assembly. An affinity ligand was attached to the DNAzyme motor via a DNA spacer, and a second affinity ligand was conjugated to the gold nanoparticle (AuNP) that was also decorated with hundreds of substrate strands serving as a high-density, three-dimensional track for the DNAzyme motor. Binding of a target molecule to the two ligands induced hybridization between the DNAzyme and its substrate on the AuNP, which are otherwise unable to spontaneously hybridize. The hybridization of DNAzyme with the substrate initiates the cleavage of the substrate and the autonomous movement of the DNAzyme along the AuNP. Each moving step restores the fluorescence of a dye molecule, enabling monitoring of the operation of the DNAzyme motor in real time. A simple addition or depletion of the cofactor Mg allows for fine control of the DNAzyme motor. The motor can translate a single binding event into cleavage of hundreds of substrates, enabling amplified detection of proteins at room temperature without the need for separation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.analchem.7b03529 | DOI Listing |
Anal Methods
December 2024
Pre-hospital Emergency Department, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing, 400014, China.
The expression levels of small extracellular vesicles (sEVs) are closely associated with several significant biological processes, which can be used as a crucial biomarker for cancer diagnosis, such as colorectal cancer. More efforts are still necessary to amplify sEV detection sensitivity, as their expression is minimal during the early stages of colorectal cancer. Through the integration of a catalytic assembly-triggered DNAzyme motor and gold nanoparticle (AuNP) aggregation, we have developed a triple signal amplified biosensor for the detection of sEVs.
View Article and Find Full Text PDFAdv Sci (Weinh)
November 2024
State Key Laboratory of Chemical Resource Engineering, College of Chemistry, Beijing University of Chemical Technology, Beijing, 10010, P. R. China.
The development of theragnostic nanosystems integrating FRET (fluorescence resonance energy transfer) imaging and chemodynamic therapy (CDT) for accurate diagnosis and effective treatment of lung tumors is still a big challenge. Herein, a peptide-assembled 3D DNAzyme motor nanodevice is engineered for a self-powered FRET amplifier profiling human neutrophil elastase (HNE) and self-supplied HO enhancing CDT. The nanodevice is prepared by depositing AuNPs on ZIF-8, in which ZIF-8 co-loaded the lysosomal targeting peptide-modified copper peroxides (PCPs) and hairpins (H1, H2, and H3), AuNPs are co-labeled by DNAzyme-peptide (DP) conjugate and H3.
View Article and Find Full Text PDFAnalyst
July 2024
Research Center for Analytical Sciences, Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China.
MicroRNA is regarded as a significant biomarker for cancer diagnosis, disease process evaluation and therapeutic guidance, and dual-parameter measurement may contribute to a more accurate and realistic assessment. To meet the urgent need for simultaneous detection of multiple biomarkers, we combined three-dimensional DNAzyme motors with single molecule imaging technique to construct a convenient, intuitive, and sensitive approach for the simultaneous detection of dual miRNAs in the free state or in extracellular vesicles. Quantification of target miRNAs can be realized through the detection of amplified fluorescence signals generated by the target miRNA-initiated cleavage of fluorescent substrate strands by the DNAzyme motors.
View Article and Find Full Text PDFNat Commun
June 2024
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
Factor-dependent termination uses molecular motors to remodel transcription machineries, but the associated mechanisms, especially in eukaryotes, are poorly understood. Here we use single-molecule fluorescence assays to characterize in real time the composition and the catalytic states of Saccharomyces cerevisiae transcription termination complexes remodeled by Sen1 helicase. We confirm that Sen1 takes the RNA transcript as its substrate and translocates along it by hydrolyzing multiple ATPs to form an intermediate with a stalled RNA polymerase II (Pol II) transcription elongation complex (TEC).
View Article and Find Full Text PDFBiotechnol Adv
September 2024
Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Oncopathology Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran; Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Applied Biotechnology Research Centre, Tehran Medical Science, Islamic Azad University, Tehran, Iran. Electronic address:
Stimulus-responsive delivery systems allow controlled, highly regulated, and efficient delivery of various cargos while minimizing side effects. Owing to the unique properties of nucleic acids, including the ability to adopt complex structures by base pairing, their easy synthesis, high specificity, shape memory, and configurability, they have been employed in autonomous molecular motors, logic circuits, reconfigurable nanoplatforms, and catalytic amplifiers. Moreover, the development of nucleic acid (NA)-responsive intelligent delivery vehicles is a rapidly growing field.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!