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Detection of miRNA Targets in High-throughput Using the 3'LIFE Assay
Published on: May 25, 2015
Direct evolution of genetic robustness in microRNA
Elhanan Borenstein1, Eytan Ruppin
1School of Computer Science and School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel. borens@post.tau.ac.il
Summary
Genetic robustness, the invariance of phenotype despite genetic changes, helps organisms resist mutations. This study shows microRNA precursor stem-loops have evolved excess robustness, suggesting direct selection for this trait.
Area of Science:
- Evolutionary biology
- Molecular genetics
- Bioinformatics
Background:
- Genetic robustness enhances organismal resilience to mutations.
- The evolutionary origins of genetic robustness remain debated: direct selection versus byproduct.
- MicroRNA (miRNA) precursor stem-loops are crucial for gene regulation.
Purpose of the Study:
- To investigate the evolutionary origins of genetic robustness in miRNA precursor stem-loops.
- To determine if excess robustness in miRNA stem-loops is adaptive or a byproduct.
Main Methods:
- Comparative analysis of miRNA precursor stem-loop structures across eukaryotic species.
- Assessment of mutational robustness against random RNA sequences.
- Evaluation of base composition bias and thermodynamic stability.
Main Results:
- miRNA precursor stem-loops exhibit significantly higher mutational robustness than random RNA sequences.
- This excess robustness is not explained by base composition or thermodynamic stability.
- Adaptive robustness in miRNA evolves to compensate for intrinsically less robust structures.
Conclusions:
- The excess robustness of miRNA precursor stem-loops is likely a result of direct evolutionary selection.
- Adaptive robustness plays a role in maintaining miRNA function.
- Evolution actively favors robustness in specific genetic elements.
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