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09:05
MicroRNA-based Regulation of Picornavirus Tropism
Published on: February 6, 2017
Argonaute 2 complexes selectively protect the circulating microRNAs in cell-secreted microvesicles
Limin Li1, Dihan Zhu, Lei Huang
1Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China.
Plos One
|October 19, 2012
Summary
Cell-secreted microRNAs (miRNAs) are protected by Argonaute 2 (Ago2) complexes and microvesicles (MVs), enhancing their stability as disease biomarkers. This Ago2 association is crucial for circulating miRNA stability, influenced by cell status.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Cell-secreted microRNAs (miRNAs) are stable biomarkers and intercellular signaling molecules.
- The mechanisms protecting circulating miRNAs remain unclear.
- Microvesicles (MVs) are key carriers of secreted miRNAs.
Purpose of the Study:
- To elucidate the protective mechanisms of circulating miRNAs within MVs.
- To investigate the role of Argonaute 2 (Ago2) in miRNA stability.
- To correlate miRNA-Ago2 association with cellular functional status.
Main Methods:
- RNaseA resistance assays on MV-encapsulated miRNAs.
- Immunoprecipitation assays to identify miRNA-associated proteins.
- Disruption of Ago2-miRNA complexes using trypaflavine.
- Analysis of miRNA stability during apoptosis and cell differentiation.
Main Results:
- MV integrity and protease sensitivity affected miRNA resistance.
- Ago2 was identified as a major miR-16-associated protein.
- Ago2-associated miR-16 exhibited enhanced RNaseA resistance.
- Disrupting Ago2-miRNA complexes decreased miRNA stability.
- Increased Ago2 association correlated with enhanced miRNA stability during apoptosis and ATRA-induced differentiation.
Conclusions:
- Ago2 complexes provide specific protection for miRNAs within MVs.
- The association of miRNAs with Ago2 is a critical factor in stabilizing circulating miRNAs.
- miRNA stability is linked to cellular functional status and Ago2 complex formation.
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