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Optimized Quantitative Assessment of Enhancer RNA Stability in Mouse Embryonic Stem Cells
Published on: November 21, 2025
MicroRNA 92b controls the G1/S checkpoint gene p57 in human embryonic stem cells.
Srikumar Sengupta1, Jeff Nie, Ryan J Wagner
1Morgridge Institute for Research, Madison, Wisconsin, USA.
Stem Cells (Dayton, Ohio)
|June 23, 2009
Summary
MicroRNA miR-92b regulates the cell cycle in human stem cells. This microRNA directly downregulates the p57 gene, impacting cell cycle progression from G1 to S phase.
Area of Science:
- Stem cell biology
- Molecular and cellular biology
- Epigenetics
Background:
- Human embryonic stem (ES) cells possess a distinct cell cycle profile, characterized by a shorter G1 phase compared to somatic cells.
- MicroRNAs (miRNAs) are key regulators of gene expression, influencing various cellular processes including cell cycle control.
Purpose of the Study:
- To investigate the role of the human ES cell-enriched microRNA, miR-92b, in regulating cell cycle distribution.
- To identify the molecular targets of miR-92b involved in cell cycle progression.
Main Methods:
- Inhibition and overexpression of miR-92b in human ES cells and differentiated cells.
- Flow cytometry analysis to assess cell cycle distribution (G1 and S phases).
- Western blot analysis to determine p57 protein levels.
- Luciferase reporter assay to validate miR-92b targeting of the p57 gene.
Main Results:
- Inhibition of miR-92b in human ES cells led to an accumulation of cells in the G1 phase and a decrease in the S phase.
- Overexpression of miR-92b in differentiated cells resulted in decreased G1 and increased S phase populations.
- miR-92b directly downregulates the expression of the G1/S checkpoint gene p57 at the protein level.
- Validation of p57 as a direct target of miR-92b using a luciferase reporter assay.
Conclusions:
- The microRNA miR-92b plays a significant role in controlling cell cycle progression in human stem cells.
- miR-92b directly targets and downregulates the p57 gene, a key inhibitor of G1 to S phase transition.
- These findings elucidate a novel regulatory mechanism of the cell cycle in human embryonic stem cells mediated by miR-92b.
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