title: The Ty1 LTR-retrotransposon population in Saccharomyces cerevisiae genome: dynamics and sequence variations during mobility.
abstract: Transposable element (TE) evolution in genomes has mostly been deduced from comparative genome analyses. TEs often account for a large proportion of the eukaryotic nuclear genome (up to 50%, depending on the species). Among the many existing genomic copies, only a small fraction may contribute to the mobility of a TE family. We have identified here, using a genetic screening procedure to trap Ty1 long terminal repeat-retrotransposon insertions in Saccharomyces cerevisiae, which among the populations of resident Ty1 copies are responsible for Ty1 mobility. Although the newly inserted Ty1 copies resulting from a single round of transposition were found to originate from a limited subset of Ty1 resident copies, they showed a high degree of diversity at the nucleotide level, mainly due to the reverse transcription-mediated recombination. In this process, highly expressed and strikingly nonautonomous mutant Ty1 were found to be the most frequently used resident copies, which suggests that nonautonomous elements play a key role in the dynamics of the Ty1 family.
authors.affiliation: Laboratoire de Génétique Moléculaire, Génomique et Microbiologie UMR7156 (Université de Strasbourg and CNRS), Strasbourg, France. bleykasten@unistra.fr
authors.forename: Claudine
authors.initials: C
authors.lastname: Bleykasten-Grosshans
authors.forename: Paul P
authors.initials: PP
authors.lastname: Jung
authors.forename: Emilie S
authors.initials: ES
authors.lastname: Fritsch
authors.forename: Serge
authors.initials: S
authors.lastname: Potier
authors.forename: Jacky
authors.initials: J
authors.lastname: de Montigny
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Souciet
mesh_terms: D004271:DNA, Fungal / Q000235:genetics; D014644:Genetic Variation; D016681:Genome, Fungal; D011995:Recombination, Genetic; D018626:Retroelements / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000166:cytology / Q000235:genetics*; D016415:Sequence Alignment; D020079:Terminal Repeat Sequences / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D018626:Retroelements