Influence of genetic background on the occurrence of chromosomal rearrangements in Saccharomyces cerevisiae.
BACKGROUND
Chromosomal rearrangements such as duplications and deletions are key factors in evolutionary processes because they promote genomic plasticity. Although the genetic variations in the Saccharomyces cerevisiae species have been well documented, there is little known to date about the impact of the genetic background on the appearance of rearrangements.


RESULTS
Using the same genetic screening, the type of rearrangements and the mutation rates observed in the S288c S. cerevisiae strain were compared to previous findings obtained in the FL100 background. Transposon-associated rearrangements, a major chromosomal rearrangement event selected in FL100, were not detected in S288c. The mechanisms involved in the occurrence of deletions and duplications in the S288c strain were also tackled, using strains deleted for genes implicated in homologous recombination (HR) or non-homologous end joining (NHEJ). Our results indicate that an Yku80p-independent NHEJ pathway is involved in the occurrence of these rearrangements in the S288c background.


CONCLUSIONS
The comparison of two different S. cerevisiae strains, FL100 and S288c, allowed us to conclude that intra-species genomic variations have an important impact on the occurrence of chromosomal rearrangement and that this variability can partly be explained by differences in Ty1 retrotransposon activity.
Fritsch
Emilie S
ES
Laboratory of Molecular Genetics, Genomics and Microbiology, UMR7156, University of Strasbourg and CNRS, Strasbourg, France. fritsch@embl.de
Schacherer
Joseph
J
Bleykasten-Grosshans
Claudine
C
Souciet
Jean-Luc
JL
Potier
Serge
S
de Montigny
Jacky
J
D002872:Chromosome Deletion; D015825:Chromosomes, Fungal / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D020440:Gene Duplication; D015321:Gene Rearrangement; D016681:Genome, Fungal; D009154:Mutation; D011995:Recombination, Genetic; D018626:Retroelements; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D004271:DNA, Fungal; D018626:Retroelements