Engineering Ligand-Interactive Hairpin-Containing I-Motif DNA as a Generic Light-Up System for Label-Free...

Area of Science:

• Biochemistry
• Cell Biology
• Analytical Chemistry

Background:

• Sulfur dioxide (SO2) is a crucial gaseous signaling molecule in cellular physiology and pathology.
• Label-free monitoring of cell surface SO2 release is essential for understanding cellular processes.

Purpose of the Study:

• To engineer a novel DNA-based fluorescent system for sensitive and specific detection of SO2.
• To develop a cell membrane-anchored sensor for real-time monitoring of SO2 release from living cells.
• To investigate the role of SO2 in lipopolysaccharide (LPS)-induced inflammation in HeLa cells.

Main Methods:

• Engineering of a hairpin-containing i-motif (iM-Hp) DNA coupled with a benzothiazole-based SO2-responsive fluorescent probe (PSMB).
• Development of a light-up fluorescence system where SO2 detection leads to decreased fluorescence.
• Construction of a cell membrane-anchored sensor for monitoring SO2 exocytosis from LPS-stimulated HeLa cells.

Main Results:

• The developed system achieves sensitive and specific detection of SO2 with a fluorescence decrease upon reaction with HSO3-.
• SO2 exocytosis from HeLa cells increases gradually within 4 hours after LPS stimulation.
• Cell viability remains largely unchanged during the observed SO2 release period.

Conclusions:

• The engineered iM-Hp/PSMB system provides a robust platform for SO2 detection and cellular monitoring.
• SO2 plays a role in the post-drug progressive process of inflammatory cells.
• The sensor holds significant potential for monitoring drug-induced early cell lesions.