Spontaneous duplications in diploid Saccharomyces cerevisiae cells.
The duplication of DNA sequences is a powerful determinant of genomic plasticity and is known to be one of the key factors responsible for evolution. Recent genomic sequence data demonstrate the abundance of duplicated genes in all surveyed organisms. Over the past years, experimental systems were adequately designed to explore the molecular mechanisms involved in their formation in haploid Saccharomyces cerevisiae strains. To obtain a more global and accurate view of the events leading to DNA sequence duplications, we have selected and characterized duplication occurrences in diploid S. cerevisiae cells. The molecular analysis showed that two other predominant ways lead to duplication in this context: formation of extra chimeric chromosomes and non-reciprocal translocation events. Moreover, we demonstrated that these two types of rearrangements are RAD52 independent and therefore that homologous recombination plays no part in their formation. Finally, our results show the multiplicity of mechanisms involved in duplication events and provide the first experimental evidence that these mechanisms might be ploidy dependent.
Schacherer
Joseph
J
UMR 7156 Université Louis-Pasteur/CNRS, Génétique Moléculaire, Génomique, Microbiologie, Département Micro-Organismes, Génomes, Environnement, 67083 Strasbourg Cedex, France. jschache@princeton.edu
Tourrette
Yves
Y
Potier
Serge
S
Souciet
Jean-Luc
JL
de Montigny
Jacky
J
D015139:Blotting, Southern; D015825:Chromosomes, Fungal; D004271:DNA, Fungal / Q000235:genetics; D004171:Diploidy; D016521:Electrophoresis, Gel, Pulsed-Field; D020440:Gene Duplication; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D051721:Rad52 DNA Repair and Recombination Protein / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics
D004271:DNA, Fungal; C497197:RAD52 protein, S cerevisiae; D051721:Rad52 DNA Repair and Recombination Protein; D029701:Saccharomyces cerevisiae Proteins