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Updated: Feb 26, 2026
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Quantitative Comparison of cis-Regulatory Element CRE Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
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Pervasive epigenetic effects of Drosophila euchromatic transposable elements impact their evolution
Yuh Chwen G Lee1,2, Gary H Karpen1,2
1Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, United States.
Elife
|July 12, 2017
Summary
Transposable elements (TEs) spread repressive epigenetic marks, influencing their evolution. This epigenetic silencing impacts TE content differently between Drosophila melanogaster and Drosophila simulans.
Area of Science:
- Evolutionary genomics
- Epigenetics
- Molecular biology
Background:
- Transposable elements (TEs) are mobile genetic sequences with significant evolutionary impact.
- The epigenetic consequences of TEs, particularly repressive marks, are not fully understood.
- Quantifying these epigenetic effects genome-wide is crucial for understanding TE evolution.
Purpose of the Study:
- To perform the first genome-wide quantification of epigenetic impacts of transposable elements.
- To investigate the role of epigenetic silencing in the evolution of TEs in Drosophila species.
- To compare epigenetic effects and TE content between Drosophila melanogaster and Drosophila simulans.
Main Methods:
- Genome-wide analysis of epigenetic marks, specifically histone H3K9me2.
- Quantification of the spread of repressive marks from euchromatic TEs into adjacent DNA.
- Comparative analysis of TE content and epigenetic states between D. melanogaster and D. simulans.
Main Results:
- Repressive epigenetic marks (H3K9me2) spread to over 50% of euchromatic TEs, extending up to 20 kb.
- This epigenetic modification leads to differential epigenetic states of genic alleles, exerting selection against TEs.
- Drosophila simulans exhibits lower TE content, correlating with stronger TE epigenetic effects and higher levels of host genetic factors promoting epigenetic silencing.
Conclusions:
- Epigenetic effects of euchromatic TEs significantly influence TE evolution within and between species.
- Host genetic factors that modulate epigenetic silencing play a critical role in TE dynamics.
- Comparative genomics and epigenetics reveal species-specific strategies in managing transposable elements.
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