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Published on: August 21, 2019
Functional siRNAs and miRNAs exhibit strand bias
Anastasia Khvorova1, Angela Reynolds, Sumedha D Jayasena
1Amgen, Inc., One Amgen Center Drive, Thousand Oaks, CA 91320, USA.
Cell
|October 22, 2003
Summary
Small interfering RNAs (siRNA) and microRNAs (miRNA) function similarly. siRNA stability at the 5' end is crucial for its function and longevity, influencing RNA interference processes.
Area of Science:
- Molecular Biology
- Biochemistry
- Genetics
Background:
- MicroRNAs (miRNA) and small interfering RNAs (siRNA) are key regulators of gene expression.
- Both utilize Dicer and the RNA-induced silencing complex (RISC) for RNA interference.
- Understanding the biophysical properties of these molecules is essential for their application.
Purpose of the Study:
- To investigate the relationship between the internal stability of miRNA precursors and siRNA duplexes and their biological function.
- To identify thermodynamic signatures associated with functional siRNA molecules.
Main Methods:
- Statistical analysis of published miRNA precursor sequences.
- Analysis of internal stability of functional and non-functional siRNA duplexes.
- Thermodynamic analysis of siRNA molecules retrieved from plant cells.
Main Results:
- miRNA precursors exhibit enhanced flexibility, particularly at the 5'-anti-sense (AS) terminal base pair.
- Functional siRNA duplexes show lower internal stability at the 5'-AS end compared to non-functional ones.
- siRNA molecules in plant cells display a characteristic thermodynamic signature linked to function.
Conclusions:
- The thermodynamic properties of siRNA, specifically its internal stability at the 5'-AS end, are critical for its function and persistence.
- These properties may influence key steps in RNA interference, such as duplex unwinding and RISC-mediated strand retention.
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