Reducible Dimeric Conjugates of Small Internally Segment Interfering RNA for Efficient Gene Silencing

Area of Science:

• Biotechnology
• Molecular Biology
• Nanomedicine

Background:

• Cationic carriers are crucial for delivering nucleic acids into cells.
• Traditional small interfering RNA (siRNA) exhibits poor association with cationic carriers due to structural rigidity and low charge density.
• Developing efficient siRNA delivery systems remains a significant challenge in gene therapy.

Purpose of the Study:

• To engineer a novel dimeric small internally segment interfering RNA (sisiRNA) conjugate for enhanced cellular uptake and gene silencing.
• To overcome the limitations of siRNA's structural properties in complexation with cationic carriers.
• To improve the efficiency of gene silencing through optimized nanostructure formation.

Main Methods:

• Synthesis of dimeric sisiRNA by oxidizing two monomeric sisiRNA molecules linked via a disulfide bond.
• Each monomeric sisiRNA consists of a nicked sense strand and a thiol-modified antisense strand.
• Characterization of nanosized complexes formed between dimeric sisiRNA and cationic carriers.

Main Results:

• The nick in the sense strand increases structural flexibility, facilitating more effective condensation into nanosized complexes.
• Dimeric sisiRNA demonstrated significantly higher gene silencing efficiency compared to dimeric siRNA with intact sense strands.
• The discontinuity in the sense strand is a key factor for improved nanostructure formation and gene silencing.

Conclusions:

• Nicked sense strands in dimeric sisiRNA enhance structural flexibility for superior nanoparticle condensation.
• This approach offers a simple yet effective strategy to improve the performance of siRNA-based nanostructures for gene delivery.
• The developed dimeric sisiRNA conjugate represents a promising advancement for efficient gene silencing applications.