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Abstract Transposable elements are genetic elements also known as “jumping genes” that increase their copy number within a host through various mechanisms of transposition. TEs can also move between species through unknown intermediaries in a process known as horizontal transfer, infecting novel genomes and increasing in copy number. While many individual invasions have been documented, a large dataset of recent horizontal transfer events that will allow us to understand larger more general HT patterns has not been assembled. In this manuscript we used almost 400 dipteran genomes to uncover 637 recent transposon invasions, mostly inDrosophila. The majority of transfers occurred between closely related species, with the cosmopolitanmelanogastergroup showing the highest recent transfer activity. We even documented a single transposon with 16 recent transfers, many between differentDrosophilagroups. Using species distance on a phylogenetic tree to measure the distance that transposons travel, we found that DNA transposons transfer between distantly related species much more frequently compared to retrotransposons. This potentially represents a different evolutionary strategy for exploiting naive genomes. Our phylogenetic framework advances the understanding of horizontal transfer dynamics at the species level withinDrosophila.
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This content will become publicly available on October 3, 2026
The ongoing invasion of the endogenous retrovirus Kuruka in natural Drosophila melanogaster populations
Abstract Transposable elements are mobile DNA sequences capable of proliferating within host genomes, occasionally capable of crossing species boundaries via horizontal transfer (HT). Here, we report the discovery and characterization ofKuruka, a newly invading endogenous retrovirus in naturalD. melanogasterpopulations.Kurukaencodes an envelope protein and belongs to thegypsy/gypsysuperfamily. Analysis of over 1000D. melanogastergenomes revealed thatKurukafirst appeared in sub-Saharan Africa in 2010. By 2017-2019Kurukahad spread to Asia, Europe and America in 2017-2019, and is still actively invading Europe and Oceania as of 2021. Phylogenomic analyses suggest thatKurukaentered inD. melanogastervia a recent HT from an AfrotropicalDrosophilaspecies, most likelyD. erecta. This is the first case of a recent HT from an Afrotropical donor species toD. melanogaster. InD. erecta, Kurukahas a single genomic insertion, which is located withinflamenco, a master regulator of TE activity. The presence of an active host defense (piRNAs) suggests thatKurukais silenced inD. erecta. Our findings establishKurukaas a valuable model for studying the early stages of TE invasions and the dynamics of genome defense in real time.
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- Award ID(s):
- 2032756
- PAR ID:
- 10663864
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- North Dakota State University
- Sponsoring Org:
- National Science Foundation
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