Target site effects in the RNA interference and microRNA pathways
Gregor Obernosterer1, Hakim Tafer, Javier Martinez
1Institute of Molecular Biotechnology, Austrian Academy of Sciences, Vienna, Austria. gregor.obernosterer@imba.oeaw.ac.at
Biochemical Society Transactions
|November 22, 2008
Summary
Target accessibility significantly enhances the effectiveness of small interfering RNAs (siRNAs) in RNA interference (RNAi). This study also suggests secondary structures play a complex role in microRNA (miRNA) target recognition.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- RNA interference (RNAi) utilizes small interfering RNAs (siRNAs) within the RNA-induced silencing complex (RISC) for target RNA cleavage.
- Despite RNAi's utility in gene function studies, many siRNAs exhibit low efficacy.
- RISC assembly and activation are known factors, but target accessibility's role in siRNA potency remains underexplored.
Purpose of the Study:
- To investigate the impact of target site accessibility on siRNA potency in RNAi.
- To explore the role of accessibility in microRNA (miRNA) target recognition and mRNA suppression.
Main Methods:
- Assessed the effect of target site accessibility on siRNA potency.
- Analyzed predicted miRNA target sites for accessibility.
- Conducted reporter gene assays to correlate accessibility with mRNA suppression levels.
Main Results:
- Target site accessibility was found to significantly improve siRNA potency.
- Predicted miRNA target sites are located in accessible regions.
- Reporter gene assays indicated a correlation between accessibility and measured mRNA suppression.
Conclusions:
- Target accessibility is a critical factor influencing siRNA efficacy in RNAi.
- Accessibility criteria may aid in identifying functional miRNA targets.
- RNA secondary structures introduce complexity to miRNA target recognition.
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