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Published on: August 21, 2014
Transposable element small RNAs as regulators of gene expression
Andrea D McCue1, R Keith Slotkin
1Department of Molecular Genetics & Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA.
Trends in Genetics : TIG
|October 9, 2012
Summary
Transposable elements (TEs) generate small RNAs that regulate genes. These TE-derived small RNAs, like PIWI-interacting RNAs (piRNAs), influence gene expression by targeting messenger RNAs, blurring traditional distinctions.
Area of Science:
- Molecular Biology
- Genetics
- Epigenetics
Background:
- Transposable elements (TEs) are sources of endogenous small RNAs in animals and plants.
- TE-derived small RNAs were traditionally considered distinct from gene-regulating small RNAs, such as microRNAs (miRNAs).
Purpose of the Study:
- To investigate the emerging role of TE-derived small RNAs in gene regulation.
- To highlight recent findings that blur the distinction between TE-derived small RNAs and gene-regulating small RNAs.
Main Methods:
- Analysis of recent reports in Drosophila and Arabidopsis concerning TE expression and small RNA production.
- Examination of specific examples: TE-derived PIWI-interacting small RNAs (piRNAs) regulating nanos mRNA in Drosophila and Athila retrotransposon-derived small RNAs targeting UBP1b mRNA in Arabidopsis.
Main Results:
- Epigenetically and developmentally regulated TE expression can produce gene-regulating small RNAs.
- In Drosophila, maternally deposited piRNAs regulate nanos mRNA via binding sites in its 3' untranslated region (UTR).
- In Arabidopsis, activated Athila retrotransposons yield small RNAs that target the 3'UTR of the UBP1b mRNA.
Conclusions:
- TE-derived small RNAs can regulate gene expression, challenging previous distinctions.
- The epigenetic status of TEs may widely influence the genic transcriptome through small RNA pathways.
- Suggests potential for other TE-derived small RNAs to regulate additional genes.
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