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Identification of Circular RNAs using RNA Sequencing
Published on: November 14, 2019
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Ouroboros resembling competitive endogenous loop (ORCEL) in circular RNAs revealed through transcriptome sequencing
Yu-Chen Liu1,2,3, Hsiao-Chin Hong2, Chi-Dung Yang2,4
1Institute of Engineering in Medicine, University of California, La Jolla, San Diego, CA, USA.
BMC Genomics
|May 17, 2018
Summary
Circular RNAs (circRNAs) act as miRNA sponges, regulating gene expression. Researchers identified a novel regulatory loop, the Ouroboros Resembling Competitive Endogenous Loop (ORCEL), involving circRNAs and microRNAs.
Area of Science:
- Molecular Biology
- Genetics
- Bioinformatics
Background:
- Circular RNAs (circRNAs) are emerging regulators of gene expression.
- A subset of circRNAs functions as microRNA (miRNA) sponges.
- Identifying novel circRNAs and their interactions is crucial for understanding gene regulation.
Purpose of the Study:
- To identify novel circRNAs and circRNA-miRNA interactions.
- To investigate the role of circRNAs as miRNA sponges.
- To propose a novel regulatory mechanism termed ORCEL.
Main Methods:
- Analysis of 465 RNA-sequencing datasets.
- Literature review of 22 published reports.
- Bioinformatic identification of circRNA-miRNA interactions.
Main Results:
- Identified circRNAs acting as miRNA sponges for their host genes.
- Observed evidence supporting a competitive endogenous relationship between circRNAs and miRNAs.
- Proposed the Ouroboros Resembling Competitive Endogenous Loop (ORCEL) model.
Conclusions:
- The origin of miRNA sponge circRNAs from miRNA target-enriched regions supports the ORCEL model.
- Conserved miRNA targeting of genes in these regions further rationalizes ORCEL.
- ORCEL provides a framework for understanding circRNA-mediated self-regulation.
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