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A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells
Published on: June 16, 2022
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m6A modification inhibits miRNAs' intracellular function, favoring their extracellular export for intercellular
Sabrina Garbo1, Daniel D'Andrea2, Alessio Colantoni3
1Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Molecular Medicine, Sapienza University of Rome, Viale Regina Elena 324, 00161 Rome, Italy.
Cell Reports
|June 15, 2024
Summary
N6-methyladenosine (m6A) modification in microRNAs (miRNAs) impairs their function and promotes their packaging into extracellular vesicles (EVs) for cell-to-cell communication.
Area of Science:
- Molecular Biology
- Epigenetics
- Cell Biology
Background:
- Epitranscriptomics, including N6-methyladenosine (m6A) modification, adds a layer to gene expression regulation.
- While m6A's impact on microRNA (miRNA) biogenesis is known, its effects on mature miRNAs are unclear.
Purpose of the Study:
- To investigate the functional consequences of m6A modification on mature miRNAs.
- To elucidate the mechanisms by which m6A affects miRNA function, localization, and intercellular transfer.
Main Methods:
- Analysis of m6A modification in specific miRNAs.
- Assessment of miRNA-AGO2 interaction and target mRNA regulation.
- Investigation of miRNA loading into extracellular vesicles (EVs) via RNA-binding proteins.
- Functional studies of EV-mediated miRNA transfer and demethylation by FTO.
Main Results:
- m6A modification weakens miRNA coupling to AGO2, impairing intracellular function.
- m6A promotes miRNA loading into EVs through hnRNPA2B1 recognition.
- EV-delivered miRNAs require FTO-mediated demethylation for function in recipient cells.
- Modified miRNAs act as intercellular signals rather than regulating endogenous targets.
Conclusions:
- m6A modification regulates mature miRNA function and intercellular communication.
- EV-packaged miRNAs carrying m6A modifications serve as regulatory signals between cells.
- This highlights a novel mechanism of cell-to-cell communication mediated by epitranscriptomic modifications of miRNAs.
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