Involvement of very short DNA tandem repeats and the influence of the RAD52 gene on the occurrence of deletions in Saccharomyces cerevisiae.
Chromosomal rearrangements, such as deletions, duplications, or Ty transposition, are rare events. We devised a method to select for such events as Ura(+) revertants of a particular ura2 mutant. Among 133 Ura(+) revertants, 14 were identified as the result of a deletion in URA2. Of seven classes of deletions, six had very short regions of identity at their junctions (from 7 to 13 bp long). This strongly suggests a nonhomologous recombination mechanism for the formation of these deletions. The total Ura(+) reversion rate was increased 4.2-fold in a rad52Delta strain compared to the wild type, and the deletion rate was significantly increased. All the deletions selected in the rad52Delta context had microhomologies at their junctions. We propose two mechanisms to explain the occurrence of these deletions and discuss the role of microhomology stretches in the formation of fusion proteins.
Welcker
A J
AJ
Laboratoire de Microbiologie et de Génétique, UPRES-A 7010, Université Louis-Pasteur/CNRS, Strasbourg, 67083, France.
de Montigny
J
J
Potier
S
S
Souciet
J L
JL
D020029:Base Pairing; D001483:Base Sequence; D015825:Chromosomes, Fungal / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics* / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D008969:Molecular Sequence Data; D009154:Mutation; D016133:Polymerase Chain Reaction; D051721:Rad52 DNA Repair and Recombination Protein; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D017384:Sequence Deletion
D004271:DNA, Fungal; D004268:DNA-Binding Proteins; C497197:RAD52 protein, S cerevisiae; D051721:Rad52 DNA Repair and Recombination Protein; D029701:Saccharomyces cerevisiae Proteins