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Marsupial-specific microRNAs evolved from marsupial-specific transposable elements

Eric J Devor1, Andrew S Peek, William Lanier

  • 1Molecular Genetics and Bioinformatics, Integrated DNA Technologies, Coralville, IA 52241, USA. eric-devor@uiowa.edu

Gene
|July 7, 2009
PubMed

Insights

New microRNAs in marsupials, like Monodelphis domestica, often originate from transposable elements. This research highlights transposable elements as a significant, previously overlooked source for novel, species-specific microRNAs.

Area of Science:

  • Genomics
  • Molecular Biology
  • Evolutionary Biology

Background:

  • MicroRNAs (miRNAs) are crucial regulators of gene expression.
  • Identifying the origins of novel miRNAs is key to understanding genome evolution.
  • Marsupial genomes offer unique insights into mammalian evolution.

Purpose of the Study:

  • To investigate the evolutionary origins of previously identified marsupial-specific microRNAs.
  • To determine the role of transposable elements in the generation of new microRNAs in Monodelphis domestica.

Main Methods:

  • Direct miRNA cloning strategy.
  • Bioinformatic analysis of pre-miRNA sequences and flanking genomic regions.
  • Comparative genomics to identify transposable element origins.

Main Results:

  • Half of the fourteen identified marsupial-specific microRNAs in Monodelphis domestica originated from marsupial-specific transposable elements.
  • Analysis of pre-miRNA structures and flanking sequences confirmed their derivation from mobile genetic elements.
  • Evidence suggests a significant contribution of transposable elements to the microRNA repertoire.

Conclusions:

  • Transposable elements are a substantial and previously underappreciated source of novel, lineage-specific microRNAs.
  • The findings contribute to our understanding of genome evolution and the dynamic nature of microRNA biogenesis.
  • Marsupial genomes provide a valuable model for studying the impact of transposable elements on gene regulation.

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