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Updated: Jul 16, 2026
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Distribution and phylogeny of Penelope-like elements in eukaryotes
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA. arkhipov@fas.harvard.edu
Systematic Biology
|March 10, 2007
Summary
Penelope-like elements (PLEs) are ancient eukaryotic retroelements. Our study reveals their evolutionary patterns and suggests they belong to a larger group of target-primed retroelements.
Area of Science:
- Molecular Biology
- Genomics
- Evolutionary Biology
Background:
- Penelope-like elements (PLEs) are eukaryotic retroelements with unique features like GIY-YIG endonuclease domains and intron retention.
- Their reverse transcriptases resemble telomerases, and they are found across diverse eukaryotes, suggesting an ancient origin.
Purpose of the Study:
- To conduct a comprehensive phylogenetic analysis of PLEs.
- To understand the evolutionary history and relationships of PLEs within the broader context of retroelements.
Main Methods:
- Phylogenetic analysis using extended sequence alignments.
- Analysis of a significantly expanded dataset of PLE sequences.
Main Results:
- PLEs show evolutionary patterns similar to non-LTR retrotransposons, with deep-branching clades originating in the Precambrian era.
- PLEs appear to have undergone more lineage losses compared to non-LTR retrotransposons.
- A new classification, eukaryotic target-primed (eTPRT) retroelements, is proposed, encompassing PLEs and non-LTR retrotransposons.
Conclusions:
- PLEs are an ancient group of retroelements with a distinct evolutionary trajectory.
- The proposed eTPRT group provides a framework for understanding the evolution of target-primed retroelements.
- Further research into PLEs can illuminate the evolution of eukaryotic genomes.
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