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Transposable elements in Drosophila montana from harsh cold environments.
Mohadeseh S Tahami1, Carlos Vargas-Chavez2, Noora Poikela1,3
1Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
Mobile DNA
|October 1, 2024
Summary
Transposable elements (TEs) in Drosophila montana genomes are linked to cold adaptation. New TE sequences were identified, with some near cold-tolerant genes and inversions, suggesting a role in extreme climate adaptation.
Area of Science:
- Genomics
- Evolutionary Biology
- Molecular Biology
Background:
- Transposable elements (TEs) significantly impact genome evolution, influencing gene expression and genetic rearrangements.
- The role of TEs in adaptation to extreme climates remains largely unexplored.
- Long-read sequencing advances the precise identification and study of functional TE effects.
Purpose of the Study:
- To investigate the association between transposable elements (TEs) and adaptation to harsh climates using Drosophila montana as a model organism.
- To identify and characterize TEs in cold-adapted Drosophila montana populations.
Main Methods:
- De novo identification and manual curation of TE sequences using PacBio long-read sequencing in five Drosophila montana genomes.
- Analysis of TE distribution, identification of potentially active TE families, and proximity to known cold-tolerant genes and inversion breakpoints.
Main Results:
- Identified 489 new TE consensus sequences, representing 92% of the total TE consensus in D. montana.
- TEs occupy 11-13% of the D. montana genome and are non-randomly distributed.
- Discovered TEs near cold-tolerant genes and inversion breakpoints, with some containing regulatory elements.
Conclusions:
- A substantial number of new TE consensus sequences were identified in D. montana, highlighting the importance of studying non-model species for a comprehensive TE repertoire.
- TEs located near cold-tolerant genes and present at high frequencies, containing regulatory regions, are strong candidates for D. montana's cold stress response.
- TEs were identified at the breakpoints of three D. montana inversions for the first time.
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