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Updated: Jul 23, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
Penelope-like elements--a new class of retroelements: distribution, function and possible evolutionary significance
1Engelhardt Institute of Molecular Biology, Moscow, Russia. misha572001@yahoo.com
Cytogenetic and Genome Research
|August 12, 2005
Summary
Researchers discovered Penelope-like elements (PLEs), a novel class of eukaryotic retroelements. The active Penelope element in Drosophila virilis causes hybrid dysgenesis and induces mutations when introduced into other species.
Area of Science:
- Genetics and Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- Retroelements are mobile genetic elements that replicate via reverse transcription.
- Hybrid dysgenesis is a phenomenon observed in hybrid organisms, often caused by transposable elements.
- Previous classifications of retroelements include LTR and non-LTR retrotransposons.
Purpose of the Study:
- To describe a newly identified class of retroelements, termed Penelope-like elements (PLEs).
- To investigate the activity and impact of the Penelope element from Drosophila virilis.
- To determine the phylogenetic relationships of PLEs with other retrotransposon groups.
Main Methods:
- Isolation and characterization of the Penelope element from Drosophila virilis.
- P element-mediated transformation to introduce D. virilis Penelope into Drosophila melanogaster.
- Bioinformatic analysis of PLE sequences from diverse eukaryotic genomes.
- Phylogenetic analysis to resolve relationships with known reverse transcriptase groups.
Main Results:
- The Penelope element from D. virilis causes hybrid dysgenesis, characterized by mobilization of transposable elements and gonadal atrophy.
- Transposition of D. virilis Penelope into D. melanogaster induces mutations and dysgenesis traits.
- PLEs possess a single open reading frame encoding reverse transcriptase (RT) and endonuclease (EN) domains.
- PLE sequences are found across diverse eukaryotes, enabling robust phylogenetic analysis.
Conclusions:
- Penelope-like elements (PLEs) represent a novel class of eukaryotic retroelements.
- PLEs are distinct from established non-LTR and LTR retrotransposons based on structural and phylogenetic evidence.
- The Penelope element is an active and potentially invasive retroelement with significant impact on host genomes.
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