1. Branched Hybridization Chain Reaction Circuit for Ultrasensitive Localizable Imaging of mRNA in Living Cells
- Author
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Han Wu, Xiang-Nan Wang, Ru-Qin Yu, Jin-Wen Liu, Jian-Hui Jiang, and Lan Liu
- Subjects
Cell studies ,Messenger RNA ,Chemistry ,Optical Imaging ,Nucleic Acid Hybridization ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Fluorescence ,0104 chemical sciences ,Analytical Chemistry ,Coupling (electronics) ,Nucleic acid thermodynamics ,Spectrometry, Fluorescence ,Intense fluorescence ,Biophysics ,Humans ,RNA, Messenger ,0210 nano-technology ,human activities ,Chain reaction ,HeLa Cells ,Electronic circuit - Abstract
Hybridization chain reaction (HCR) circuits are valuable approaches to monitor low-abundance mRNA, and current HCR is still subjected to issues such as limited amplification efficiency, compromised localization resolution, or complicated designs. We report a novel branched HCR (bHCR) circuit for efficient signal-amplified imaging of mRNA in living cells. The bHCR can be realized using a simplified design by hierarchically coupling two HCR circuits with two split initiator fragments of the secondary HCR circuit incorporated in the probes for the primary HCR circuit. The bHCR circuit enables one to generate a hyperbranched assembly seeded from a single target initiator, affording the potential for localizing single target molecules in live cells. In vitro assays show that bHCR offers very high amplification efficiency and specificity in single mismatch discrimination with a detection limit of 500 fM. Live cell studies reveal that bHCR displays intense fluorescence spots indicating mRNA localization in living cells with improved contrast. The bHCR method can provide a useful platform for low-abundance biomarker detection and imaging for cell biology and diagnostics.
- Published
- 2018