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Updated: Jun 25, 2026
13:10
Use of Alu Element Containing Minigenes to Analyze Circular RNAs
Published on: March 10, 2020
Evidence for co-evolution between human microRNAs and Alu-repeats
Stefan Lehnert1, Peter Van Loo, Pushpike J Thilakarathne
1Gene Expression Unit, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium.
Plos One
|February 12, 2009
Summary
Human microRNAs (miRNAs) interact with Alu repeats, the most abundant elements in the genome. This suggests a co-evolutionary relationship where miRNAs may regulate Alu transposition, protecting the genome.
Area of Science:
- Genomics
- Molecular Biology
- Bioinformatics
Background:
- Alu repeats are the most abundant repetitive elements in the human genome.
- MicroRNAs (miRNAs) are small RNAs regulating gene expression post-transcriptionally.
Purpose of the Study:
- To investigate the relationship between human microRNAs and Alu repeats.
- To explore potential co-evolutionary mechanisms between miRNAs and repetitive elements.
Main Methods:
- Analysis of base-pair complementarity between miRNA seed sequences and Alu repeats in mRNAs.
- Identification of conserved Alu target sites within miRNAs.
- Comparative genomics of a primate-specific miRNA gene cluster on chromosome 19 and associated LINE elements.
Main Results:
- Demonstrated base-pair complementarity between a subset of human miRNAs and sense-integrated Alu repeats.
- Identified the most conserved part of Alu as a common miRNA target site.
- Found a primate-specific miRNA cluster on chromosome 19, with genes flanked by duplicated Alu-LINE signatures.
- Evidence of gene duplication events within the miRNA cluster, supported by LINE element variations.
Conclusions:
- A dual relationship exists between an evolutionarily young miRNA cluster and its Alu targets, suggesting co-evolution.
- Hypothesized that these miRNAs may protect the genome by limiting excessive duplicative transposition of Alu elements.
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