Aptamer Displacement Reaction from Live-Cell Surfaces and Its Applications

Area of Science:

• Biochemistry
• Molecular Biology
• Biotechnology

Background:

• DNA strand displacement is crucial for nucleic acid-based networks but challenging in complex biological environments.
• Aptamers offer high affinity and selectivity for biomolecules, bridging nucleic acids with diverse targets.
• Efficient removal of aptamers from cell surfaces is needed to prevent false signals and improve assays.

Purpose of the Study:

• To develop facile and efficient methods for aptamer displacement from living cell surfaces.
• To investigate the kinetics of aptamer displacement in complex cellular environments.
• To demonstrate the utility of aptamer displacement in biological applications like protein detection and cell selection.

Main Methods:

• Developed three aptamer displacement methods: complement DNA (cDNA), toehold-labeled cDNA (tcDNA), and single-stranded binding protein (SSB).
• Investigated the kinetics of DNA strand displacement on natural cell membranes.
• Evaluated the efficiency of aptamer removal and its impact on downstream applications.

Main Results:

• Toehold-mediated and SSB-mediated aptamer displacement significantly enhanced reaction kinetics.
• These methods achieved rapid and complete aptamer removal, preventing false signals from internalization.
• Aptamer displacement facilitated detection of post-translational membrane protein modifications and improved cell-SELEX efficiency.

Conclusions:

• Developed efficient aptamer displacement strategies for cell surface applications.
• Enhanced kinetics via toehold-mediated and SSB-mediated approaches overcome challenges of complex cellular environments.
• Aptamer displacement is a valuable tool for improving the accuracy and efficiency of cell-based biological assays and selection processes.