A strategy for developing a hammerhead ribozyme for selective RNA cleavage depending on substitutional RNA editing

Area of Science:

• Molecular Biology
• Biochemistry
• RNA Therapeutics

Background:

• Substitutional RNA editing, including adenosine to inosine (A-to-I) and cytosine to uracil (C-to-U) modifications, is vital for regulating gene expression and biological functions.
• Targeted RNA cleavage is a valuable tool for studying and manipulating RNA editing processes within cells.
• Hammerhead ribozymes are efficient catalytic RNAs capable of site-specific RNA cleavage, offering potential for RNA-editing-dependent applications.

Purpose of the Study:

• To design and validate a novel hammerhead ribozyme strategy for specifically recognizing and cleaving RNA at substitutional RNA editing sites.
• To demonstrate the efficacy of this strategy for both A-to-I and C-to-U RNA editing events.
• To provide a foundation for developing RNA-editing-dependent RNA degradation systems for therapeutic or research purposes.

Main Methods:

• Designed hammerhead ribozymes engineered to recognize specific RNA editing sites by pairing with the edited base.
• Tested the A-to-I editing-specific ribozyme activity against synthetic serotonin receptor 2C mRNA fragments.
• Assessed the C-to-U editing-specific ribozyme activity against synthetic apolipoprotein B mRNA fragments.
• Validated the A-to-I editing-specific ribozyme activity on endogenous filamin A (FLNA) mRNA extracted from cells.

Main Results:

• The designed hammerhead ribozymes exhibited specific cleavage activity dependent on the presence of A-to-I and C-to-U RNA edits in vitro.
• Successful editing-specific cleavage was observed against synthetic RNA fragments mimicking known editing sites.
• The ribozyme demonstrated efficacy in cleaving physiologically edited FLNA mRNA, confirming its applicability to endogenous targets.
• The strategy proved effective for RNA cleavage in an editing-dependent manner.

Conclusions:

• A novel design strategy for hammerhead ribozymes enables specific recognition and cleavage of A-to-I and C-to-U RNA editing sites.
• This approach provides a powerful tool for analyzing and potentially manipulating RNA editing processes.
• The findings support the potential application of these ribozymes for RNA-editing-dependent RNA degradation in vivo.