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Analysis of Combinatorial miRNA Treatments to Regulate Cell Cycle and Angiogenesis
Published on: March 30, 2019
MicroRNA-221-222 regulate the cell cycle in mast cells
Ramon J Mayoral1, Matthew E Pipkin, Mikhail Pachkov
1Institute for Research in Biomedicine, Bellinzona, Switzerland.
Journal of Immunology (Baltimore, Md. : 1950)
|December 26, 2008
Summary
MicroRNAs (miRNAs) are key regulators in cells. This study shows miR-221-222 are up-regulated in activated mast cells and regulate cell cycle progression.
Area of Science:
- Immunology
- Molecular Biology
- Genetics
Background:
- MicroRNAs (miRNAs) are small noncoding RNAs regulating gene expression posttranscriptionally.
- Differential miRNA expression influences protein repertoires during development, differentiation, and disease.
- Mast cells are crucial innate immune cells involved in inflammatory responses.
Purpose of the Study:
- To investigate the role of miRNAs in differentiated innate immune cells, using mast cells as a model.
- To identify the regulatory mechanisms controlling miR-221-222 transcription.
- To elucidate the functional impact of miR-221-222 on mast cell behavior and cell cycle.
Main Methods:
- Mast cell activation and analysis of miRNA expression.
- Bioinformatic and experimental approaches to identify regulatory elements of miR-221-222.
- Overexpression studies in mast cell lines and embryonic stem cells.
- Analysis of p27(kip1) mRNA isoforms and their regulation by miRNAs.
Main Results:
- miR-221-222 were significantly up-regulated upon mast cell activation.
- Signaling pathways, transcription factors, and cis-regulatory regions controlling miR-221-222 transcription were identified.
- Overexpression of miR-221-222 perturbed mast cell morphology and cell cycle regulation.
- miR-221-222 partially counteracted p27(kip1) expression, with regulation dependent on p27(kip1) mRNA 3' UTR isoforms.
- Transgenic expression of miR-221-222 in embryonic stem cells reduced proliferation and accumulation.
Conclusions:
- miR-221-222 play a significant role in regulating cell cycle checkpoints in mast cells following activation.
- The study provides insights into the transcriptional regulation of miR-221-222.
- Alternative splicing of p27(kip1) influences its susceptibility to miR-221-222-mediated regulation.
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