XRCC2 and XRCC3, new human Rad51-family members, promote chromosome stability and protect against DNA cross-links and other damages

Mol Cell. 1998 May;1(6):783-93. doi: 10.1016/s1097-2765(00)80078-7.


The phenotypically similar hamster mutants irs1 and irs1SF exhibit high spontaneous chromosome instability and broad-spectrum mutagen sensitivity, including extreme sensitivity to DNA cross-linking agents. The human XRCC2 and XRCC3 genes, which functionally complement irs1 and irs1SF, respectively, were previously mapped in somatic cell hybrids. Characterization of these genes and sequence alignments reveal that XRCC2 and XRCC3 are members of an emerging family of Rad51-related proteins that likely participate in homologous recombination to maintain chromosome stability and repair DNA damage. XRCC3 is shown to interact directly with HsRad51, and like Rad55 and Rad57 in yeast, may cooperate with HsRad51 during recombinational repair. Analysis of the XRCC2 mutation in irs1 implies that XRCC2's function is not essential for viability in cultured hamster cells.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Chromosomes / physiology*
  • Chromosomes / radiation effects
  • Cricetinae
  • Cross-Linking Reagents / metabolism
  • DNA Damage / physiology*
  • DNA, Complementary
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • DNA-Binding Proteins / radiation effects
  • Genetic Complementation Test
  • Genome, Human
  • HeLa Cells
  • Humans
  • Molecular Sequence Data
  • Precipitin Tests
  • RNA, Messenger / analysis
  • Rad51 Recombinase
  • Sequence Homology, Amino Acid
  • Transformation, Genetic
  • Yeasts / genetics


  • Cross-Linking Reagents
  • DNA, Complementary
  • DNA-Binding Proteins
  • RNA, Messenger
  • XRCC2 protein, human
  • RAD51 protein, human
  • Rad51 Recombinase