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Updated: Jun 2, 2026
06:48
A Reporter Assay to Analyze Intronic microRNA Maturation in Mammalian Cells
Published on: June 16, 2022
HuR-dependent loading of miRNA RISC to the mRNA encoding the Ras-related small GTPase RhoB controls its translation
V Glorian1, G Maillot, S Polès
1Institut National de la Santé et de la Recherche Médicale U, Toulouse, France.
Cell Death and Differentiation
|April 30, 2011
Summary
MicroRNA-19 (miR-19) regulates RhoB expression in skin cells during UV stress. This regulation depends on HuR protein binding, impacting cell survival and apoptosis pathways.
Area of Science:
- Molecular Biology
- Cellular Stress Response
- Gene Regulation
Background:
- Post-transcriptional control is crucial for gene expression during cellular stress.
- MicroRNAs (miRNAs) are key regulators of gene expression, influencing cell survival and apoptosis.
- The miR-17-92 cluster, including miR-19, plays a role in oncogenesis and stress responses.
Purpose of the Study:
- To investigate the role of miR-19 in regulating Ras homolog B (RhoB) expression in keratinocytes exposed to ultraviolet (UV) radiation.
- To elucidate the mechanism of miR-19-mediated RhoB regulation, focusing on the involvement of RNA-binding proteins.
Main Methods:
- Analysis of miR-19 expression levels in keratinocytes following UV irradiation.
- Investigating the interaction between miR-19, RhoB mRNA, and the human antigen R (HuR) protein.
- Assessing the impact of UV exposure on the binding dynamics of HuR and miR-19 to RhoB mRNA.
Main Results:
- miR-19 expression was not significantly altered by UV treatment in keratinocytes.
- miR-19 regulates the expression of the anti-apoptotic protein RhoB.
- Regulation of RhoB by miR-19 requires the binding of HuR to the 3'-untranslated region of RhoB mRNA.
Conclusions:
- UV exposure disrupts the interdependent binding of HuR and miR-19 to RhoB mRNA.
- This disruption relieves miR-19-dependent translational inhibition of RhoB mRNA.
- The findings suggest a novel mechanism contributing to the apoptotic response following UV radiation.
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