Knockdown of nuclear-retained long noncoding RNAs using modified DNA antisense oligonucleotides

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Long noncoding RNAs (lncRNAs) are increasingly recognized for their roles in cellular functions.
• A significant portion of lncRNAs reside in the cell nucleus, regulating key nuclear processes.
• Existing RNA interference (RNAi) tools like siRNAs and shRNAs are often inefficient for depleting nuclear lncRNAs due to cytoplasmic localization of the RNAi machinery.

Purpose of the Study:

• To introduce and validate chemically modified chimeric DNA antisense oligonucleotides (ASOs) as an effective tool for targeting nuclear-retained lncRNAs.
• To provide a detailed workflow for the design, synthesis, and delivery of ASOs for lncRNA knockdown.

Main Methods:

• Design and chemical modification of chimeric DNA antisense oligonucleotides (ASOs).
• In vitro and in vivo studies to assess the efficacy of ASOs in knocking down nuclear-retained lncRNAs.
• Evaluation of ASO delivery methods for nuclear targeting.

Main Results:

• Demonstrated effective knockdown of nuclear-retained lncRNAs using chemically modified chimeric DNA ASOs.
• Established a comprehensive workflow for ASO application in lncRNA research.
• Showcased the potential of ASOs to overcome the limitations of traditional RNAi methods for nuclear targets.

Conclusions:

• Chemically modified chimeric DNA ASOs represent a powerful and effective genetic tool for functional studies of nuclear-retained lncRNAs.
• This methodology facilitates the exploration of the nuclear 'dark matter' and its regulatory roles.
• ASOs provide a viable alternative for loss-of-function studies of nuclear lncRNAs where siRNAs/shRNAs are insufficient.