Conjugating pyrene onto PNA-based fluorescent probes for improved detection selectivity toward double-stranded siRNA

Area of Science:

• Biochemistry
• Molecular Biology
• Chemical Biology

Background:

• Accurate detection of specific RNA sequences is crucial for molecular diagnostics and therapeutics.
• Distinguishing between double-stranded and single-stranded forms of small interfering RNA (siRNA) is essential for understanding gene silencing mechanisms and therapeutic efficacy.
• Existing detection methods may lack the specificity required to differentiate between intact and degraded siRNA molecules.

Purpose of the Study:

• To design and synthesize novel fluorescent probes for the selective detection of intact double-stranded siRNAs.
• To enhance the selectivity of siRNA detection by discriminating against single-stranded forms.
• To develop a tool for improved monitoring of siRNA stability and activity in biological systems.

Main Methods:

• Conjugation of a pyrene unit to a peptide nucleic acid (PNA) backbone.
• Incorporation of a thiazole orange base surrogate into the PNA structure.
• Characterization of the fluorescent probe's binding affinity and selectivity towards double-stranded siRNAs with 3'-overhangs.

Main Results:

• The developed fluorescent probes demonstrate improved detection selectivity for intact double-stranded siRNAs compared to single-stranded forms.
• The pyrene unit and PNA structure enable simultaneous recognition of the 3'-overhang and double-stranded regions of target siRNAs.
• The probes exhibit specific fluorescence responses upon binding to target double-stranded siRNAs.

Conclusions:

• The novel pyrene-conjugated PNA-based fluorescent probes offer a promising approach for highly selective siRNA detection.
• These probes can serve as valuable tools for research in RNA interference (RNAi) and the development of nucleic acid-based therapeutics.
• The design strategy provides a foundation for creating advanced molecular probes with tailored recognition capabilities.