• Joseph A Farah
    Fred Hutchinson Cancer Research Center, Seattle, WA 98109
  • Edgar Hartsuiker
    University of Sussex
  • Ken-ichi Mizuno
    RIKEN Institute, Saitama
  • Kunihiro Ohta
    RIKEN Institute, Saitama
  • Gerald R Smith
    Fred Hutchinson Cancer Research Center, Seattle, WA 98109

Palindromic sequences can form hairpin and cruciform structures that pose a threat to genome integrity. We found that a 160-bp palindrome (an inverted repeat of 80 bp) conferred a mitotic recombination hotspot relative to a control nonpalindromic sequence when inserted into the ade6 gene of Schizosaccharomyces pombe. The hotspot activity of the palindrome, but not the basal level of recombination, was abolished by a rad50 deletion, by a rad50S "separation of function" mutation, or by a rad32-D25A mutation in the nuclease domain of the Rad32 protein, an Mre11 homolog. We propose that upon extrusion of the palindrome the Rad50.Rad32 nuclease complex recognizes and cleaves the secondary structure thus formed and generates a recombinogenic break in the DNA.

Keywords

  • DNA-Binding Proteins, Diploidy, Fungal Proteins, Haploidy, Mitosis, Plasmids, Rad52 DNA Repair and Recombination Protein, Recombination, Genetic, Repetitive Sequences, Nucleic Acid, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Schizosaccharomyces, Journal Article, Research Support, U.S. Gov't, P.H.S.
Original languageEnglish
Pages (from-to)461-8
Number of pages8
JournalGenetics
Volume161
Issue number1
Publication statusPublished - May 2002
Externally publishedYes
View graph of relations