Striking structural dynamism and nucleotide sequence variation of the transposon Galileo in the genome of Drosophila mojavensis

Galileo is a transposable element responsible for the generation of three chromosomal inversions in natural populations of Drosophila buzzatii. Although the most characteristic feature of Galileo is the long internally-repetitive terminal inverted repeats (TIRs), which resemble the Drosophila Foldba...

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Detalles Bibliográficos
Autores: Marzo, Mar, Bello, Xabier, Puig Font, Marta|||0000-0002-4439-6372, Maside, Xulio, Ruiz, Alfredo|||0000-0002-3605-5922
Tipo de recurso: artículo
Fecha de publicación:2013
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:184902
Acceso en línea:https://ddd.uab.cat/record/184902
https://dx.doi.org/urn:doi:10.1186/1759-8753-4-6
Access Level:acceso abierto
Palabra clave:Transposable element
Drosophila mojavensis
Evolution
Terminal inverted repeat
Phylogeny
Genomics
Descripción
Sumario:Galileo is a transposable element responsible for the generation of three chromosomal inversions in natural populations of Drosophila buzzatii. Although the most characteristic feature of Galileo is the long internally-repetitive terminal inverted repeats (TIRs), which resemble the Drosophila Foldback element, its transposase-coding sequence has led to its classification as a member of the P-element superfamily (Class II, subclass 1, TIR order). Furthermore, Galileo has a wide distribution in the genus Drosophila, since it has been found in 6 of the 12 Drosophila sequenced genomes. Among these species, D. mojavensis, the one closest to D. buzzatii, presented the highest diversity in sequence and structure of Galileo elements. In the present work, we carried out a thorough search and annotation of all the Galileo copies present in the D. mojavensis sequenced genome. In our set of 170 Galileo copies we have detected 5 Galileo subfamilies (C, D, E, F, and X) with different structures ranging from nearly complete, to only 2 TIR or solo TIR copies. Finally, we have explored the structural and length variation of the Galileo copies that point out the relatively frequent rearrangements within and between Galileo elements. Different mechanisms responsible for these rearrangements are discussed. Although Galileo is a transposable element with an ancient history in the D. mojavensis genome, our data indicate a recent transpositional activity. Furthermore, the dynamism in sequence and structure, mainly affecting the TIRs, suggests an active exchange of sequences among the copies. This exchange could lead to new subfamilies of the transposon, which could be crucial for the long-term survival of the element in the genome.