Efficient Modulation of Exon Skipping via Antisense Circular RNAs

Area of Science:

• Molecular Biology
• RNA Therapeutics
• Genetic Medicine

Background:

• Exon skipping is crucial for treating genetic disorders.
• Current methods like antisense oligonucleotides (ASOs) and U7 small nuclear ribonucleoprotein (U7 Sm OPT) face challenges in delivery and safety.
• There is a need for more effective and targeted RNA splicing modulation tools.

Purpose of the Study:

• To investigate the potential of antisense circular RNAs (AS-circRNAs) as a novel tool for exon skipping.
• To compare the efficacy and specificity of AS-circRNAs against existing methods.
• To evaluate the therapeutic potential of AS-circRNAs in a Duchenne muscular dystrophy mouse model.

Main Methods:

• AS-circRNAs were designed and synthesized to target specific pre-mRNA transcripts.
• Exon skipping efficiency was assessed using minigene and endogenous transcript assays.
• Comparison of AS-circRNA efficacy against U7 Sm OPT was performed.
• Adeno-associated virus (AAV) vectors were used for in vivo delivery of AS-circRNAs.
• Dystrophin expression and muscle function were evaluated in a Duchenne muscular dystrophy mouse model.

Main Results:

• AS-circRNAs effectively mediated exon skipping in both minigene and endogenous contexts.
• AS-circRNAs exhibited higher exon skipping efficiency than U7 Sm OPT for the tested Dmd minigene.
• AS-circRNAs demonstrated specific targeting of pre-mRNA splicing with no observed off-target effects.
• AAV-delivered AS-circRNAs successfully corrected the open reading frame and restored dystrophin expression in a Duchenne muscular dystrophy mouse model.

Conclusions:

• AS-circRNAs represent a viable alternative method for modulating RNA splicing.
• This novel approach holds significant potential as a therapeutic tool for genetic diseases.
• Further research into AS-circRNAs could lead to advanced treatments for conditions like Duchenne muscular dystrophy.