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Decoding microRNA arm switching: a key to evolutionary innovation and gene regulation
Danillo Pinhal1, Leandro de B Gonçalves2, Vinícius F Campos3
1Genomics and Molecular Evolution Laboratory, Department of Chemical and Biological Sciences, Institute of Biosciences, DCQB, IBB, UNESP, Botucatu, SP, CEP 18618-689, Brazil. danillo.pinhal@unesp.br.
Cellular and Molecular Life Sciences : CMLS
|May 10, 2025
Summary
MicroRNA (miRNA) arm switching, using either the 5p or 3p strand, fine-tunes gene expression. This conserved mechanism drives adaptive evolution and phenotypic diversity across species.
Area of Science:
- Molecular Biology
- Genetics
- Evolutionary Biology
Background:
- MicroRNAs (miRNAs) regulate gene expression by guiding target recognition.
- miRNA arm switching involves the preferential selection of either the 5p or 3p miRNA strand from a duplex.
- This process is crucial for adapting to various biological conditions and has evolutionary significance.
Purpose of the Study:
- To review and synthesize current knowledge on miRNA arm switching.
- To highlight its role as a conserved regulatory mechanism.
- To explore its implications for gene regulatory networks, phenotypic plasticity, and evolution.
Main Methods:
- Literature review and synthesis of existing research on miRNA arm switching.
- Analysis of studies investigating the mechanisms (e.g., thermodynamics, enzyme processing) and evolutionary impact of arm switching.
- Examination of the relationship between arm switching, miRNA gene duplication, and functional diversification.
Main Results:
- miRNA arm switching is a conserved mechanism across diverse species.
- It allows for dynamic regulation of gene expression, contributing to phenotypic diversity.
- The mechanisms driving arm switching are complex and not fully elucidated.
Conclusions:
- miRNA arm switching significantly expands miRNA functionality and regulatory capacity.
- This mechanism plays a key role in driving phenotypic plasticity and evolutionary innovation.
- Co-evolution with miRNA gene duplications fuels the diversification of biological functions.
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