Protein scaffolded DNA tetrads enable efficient delivery and ultrasensitive imaging of miRNA through crosslinking hybridization chain reaction.
Du-Juan HuangZhi-Mei HuangHu-Yan XiaoZhen-Kun WuLi-Juan TangJian-Hui JiangPublished in: Chemical science (2018)
Efficient intracellular delivery of nucleic acids to achieve sensitive detection and gene regulation is essential for chemistry and biology. Here we developed a novel protein scaffolded DNA tetrad, a four-arm DNA nanostructure constructed using streptavidin (SA) protein and four biotinylated hairpin DNA probes for efficient nucleic acid delivery and ultrasensitive miRNA imaging through crosslinking hybridization chain reaction (cHCR). DNA tetrads were easy to prepare and allowed precise control of the structure of the probes. DNA tetrads showed rapid intracellular delivery of DNA probes and high efficiency in lysosome escape by using confocal images for individual cells and flow cytometry for a large population of cells. cHCR allowed generating clumps of crosslinked hydrogel networks specifically to target miRNA, affording high sensitivity and spatial resolution for imaging. To our knowledge, this is the first time that HCR amplification has been realized in situ on nanostructures. Moreover, the FRET based design of cHCR conferred improved precision with the use of dual-emission ratiometric imaging to avoid false signals in biological systems. Intracellular imaging experiments further showed that DNA tetrad based cHCR could realize ultrasensitive and accurate miRNA imaging in living cells. Moreover, DNA tetrad based cHCR provided a potential tool for quantitative measurement of intracellular miRNA. The results suggested that this developed strategy provided a useful platform for nucleic acid delivery and low level biomarker imaging.
Keyphrases
- nucleic acid
- single molecule
- living cells
- high resolution
- circulating tumor
- cell free
- sensitive detection
- fluorescent probe
- quantum dots
- healthcare
- fluorescence imaging
- flow cytometry
- small molecule
- drug delivery
- oxidative stress
- high efficiency
- wastewater treatment
- signaling pathway
- deep learning
- cell death
- cell proliferation
- mass spectrometry
- label free
- simultaneous determination
- photodynamic therapy
- climate change
- binding protein
- nitric oxide