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Published on: June 3, 2011
hobo transposable elements in Drosophila melanogaster and D. simulans
1Department of Biology, Loyola University of Chicago, Illinois 60626.
Genetical Research
|August 1, 1991
Summary
The transposable element hobo shows varied genomic occurrence in Drosophila melanogaster and D. simulans, with both complete and absent forms found. This suggests hobo
Area of Science:
- Genomics
- Molecular Evolution
- Transposable Elements
Background:
- Transposable elements (TEs) like hobo play a significant role in genome evolution.
- Polymorphism in TE occurrence can provide insights into species divergence and evolutionary history.
- Drosophila melanogaster and D. simulans are sibling species, making them ideal for comparative genomic studies.
Purpose of the Study:
- To investigate the genomic distribution and patterns of the hobo transposable element in Drosophila melanogaster and D. simulans.
- To understand the evolutionary implications of hobo element presence and absence in these sibling species.
- To characterize different forms of hobo elements, including internally deleted variants.
Main Methods:
- Comparative genomics analysis of hobo element occurrence across multiple strains of D. melanogaster and D. simulans.
- Molecular characterization of canonical and internally deleted hobo elements.
- Phylogenetic analysis to infer the evolutionary history of hobo elements.
Main Results:
- Genomic patterns of hobo element occurrence are polymorphic in both D. melanogaster and D. simulans.
- Both species exhibit strains with complete hobo elements (H lines) and strains lacking them (E lines).
- Internally deleted elements (Th1, Th2, h del sim) are abundant in D. melanogaster and D. simulans, respectively.
- Numerous hobo-hybridizing sequences, not closely related to canonical hobo, exist in these species and their relatives.
Conclusions:
- The presence of both H and E lines in D. simulans challenges hypotheses of recent hobo introduction solely in D. melanogaster.
- The distinct internally deleted elements in each species suggest independent evolutionary trajectories or differential regulation.
- A broader diversity of hobo-related sequences exists beyond the canonical elements, highlighting the complexity of TE evolution in Drosophila.
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