Visualization of recombination intermediates produced by RAD52-mediated single-strand annealing

EMBO Rep. 2001 Oct;2(10):905-9. doi: 10.1093/embo-reports/kve201. Epub 2001 Sep 24.


Double-strand breaks (DSBs) occur frequently during DNA replication. They are also caused by ionizing radiation, chemical damage or as part of the series of programmed events that occur during meiosis. In yeast, DSB repair requires RAD52, a protein that plays a critical role in homologous recombination. Here we describe the actions of human RAD52 protein in a model system for single-strand annealing (SSA) using tailed (i.e. exonuclease resected) duplex DNA molecules. Purified human RAD52 protein binds resected DSBs and promotes associations between complementary DNA termini. Heteroduplex intermediates of these recombination reactions have been visualized by electron microscopy, revealing the specific binding of multiple rings of RAD52 to the resected termini and the formation of large protein complexes at heteroduplex joints formed by RAD52-mediated annealing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Baculoviridae / metabolism
  • Cell Line
  • DNA Damage*
  • DNA Repair*
  • DNA, Complementary / metabolism
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • DNA-Binding Proteins / physiology*
  • Dose-Response Relationship, Drug
  • Humans
  • Insecta
  • Microscopy, Electron
  • Models, Genetic
  • Plasmids / metabolism
  • Rad52 DNA Repair and Recombination Protein
  • Recombinant Proteins / metabolism
  • Recombination, Genetic*
  • Time Factors


  • DNA, Complementary
  • DNA-Binding Proteins
  • RAD52 protein, human
  • Rad52 DNA Repair and Recombination Protein
  • Recombinant Proteins