Sulfonated Pyrene as a Photoregulator for Single-Stranded DNA Looping

Area of Science:

• Biochemistry and Molecular Biology
• Materials Science
• Photochemistry

Background:

• Photoregulators offer spatiotemporal control over biomolecule conformation and function for disease treatment and smart nanomaterials.
• Achieving efficient and precise regulation of biomolecules under physiological conditions remains a significant challenge.

Purpose of the Study:

• To synthesize and evaluate sulfonated pyrene (SPy) as a novel photoregulator for controlling single-stranded DNA (ssDNA) looping.
• To investigate the mechanism of SPy-mediated ssDNA looping and its potential for biomolecule manipulation in aqueous solutions.

Main Methods:

• Synthesis of sulfonated pyrene (SPy) for enhanced water solubility.
• Modification of ssDNA with SPy and subsequent irradiation to induce photoionization.
• Analysis of SPy radical cation (SPy·+) formation, dimerization (SPy2·+), and its effect on ssDNA conformation.

Main Results:

• SPy was successfully synthesized and demonstrated water solubility, suitable for biomolecular studies.
• Irradiation induced SPy photoionization, forming SPy·+ and subsequently SPy2·+.
• The energy released during SPy2·+ formation drove ssDNA looping, with the dimer trapping the looped conformation and enabling dynamic studies.

Conclusions:

• Sulfonated pyrene (SPy) effectively regulates ssDNA looping through a light-stimulated dimerization mechanism.
• SPy shows significant potential as a photoregulator for controlling biomolecule conformation and function under physiological conditions.
• This study opens avenues for developing light-controllable DNA-based nanomaterials and therapeutic strategies.