Drosophila Transposons: Characterization, Regulation and Their Role in Genome Evolution

doi:10.12300/j.issn.1674-5817.2025-112

Abstract

Abstract:

Transposable elements (TEs) are mobile DNA sequences in genomes that play key roles in species evolution, genome stability, and gene regulation. Drosophila melanogaster is a classic model animal with about 20% transposons in its genome, which makes it an ideal model for studying the biological properties, host defense mechanisms, and functional evolution of TEs. Its discovery provides an important paradigm for understanding the relevant mechanisms in higher organisms and even in humans. This review systematically elucidates the classification and distribution characteristics of transposons in D. melanogaster and their interactions with the host genome, mainly focused on discussing the host defense system centered on the Piwi-interacting RNA (piRNA) pathway. Additionally, we analyze the biological properties of key transposon families (e.g., Gypsy, Copia, P-element and I-element) in Drosophila, as well as their dual roles in genome evolution. On the one hand, transposon insertions have been demonstrated to trigger genomic instability, heterozygous sterility and aging phenotypes, thus providing a suitable model basis for the study of related human diseases (e.g., neurodegenerative diseases, genomic instability syndromes, etc. ). On the other hand, their sequences can be co-opted by the host to create novel regulatory elements or functional genes, thereby driving adaptive innovation. Finally, we discuss future research directions, including the regulation of transposon activity by environmental stress, the interaction of the piRNA pathway with other small RNA systems, and the molecular mechanisms of transposons in aging and neurodegenerative diseases. The study of Drosophila transposons has been demonstrated to facilitate a more profound comprehension of transposon biology, whilst concomitantly unveiling conserved mechanisms and principles that provide a theoretical foundation and significant insights into the study of human diseases utilising experimental animal models. Furthermore, these insights are instrumental in the development of gene therapy and gene editing technologies.

Key words: Drosophila, Transposons, piRNA, Functional evolution, Host interactions

WANG Ye,WANG Lu. Drosophila Transposons: Characterization, Regulation and Their Role in Genome Evolution[J]. Laboratory Animal and Comparative Medicine. DOI: 10.12300/j.issn.1674-5817.2025-112.

Figures/Tables 3

References 77

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