Structure of an Xrcc4-DNA ligase IV yeast ortholog complex reveals a novel BRCT interaction mode

DNA Repair (Amst). 2006 Mar 7;5(3):362-8. doi: 10.1016/j.dnarep.2005.11.004. Epub 2006 Jan 18.


DNA ligase IV catalyses the final ligation step in the non-homologous end-joining (NHEJ) DNA repair pathway and requires interaction of the ligase with the Xrcc4 'genome-guardian', an essential NHEJ factor. Here we report the 3.9 A crystal structure of the Saccharomyces cerevisiae Xrcc4 ortholog ligase interacting factor 1 (Lif1p) complexed with the C-terminal BRCT domains of DNA ligase IV (Lig4p). The structure reveals a novel mode of protein recognition by a tandem BRCT repeat, and in addition provides a molecular basis for a human LIG4 syndrome clinical condition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • BRCA1 Protein / chemistry
  • Crystallization
  • Crystallography, X-Ray
  • DNA Damage
  • DNA Ligase ATP
  • DNA Ligases / chemistry*
  • DNA Ligases / genetics
  • DNA Repair
  • DNA, Fungal / genetics
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics
  • Molecular Sequence Data
  • Molecular Structure
  • Protein Structure, Tertiary
  • Saccharomyces cerevisiae / enzymology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / genetics
  • Sequence Homology, Amino Acid


  • BRCA1 Protein
  • DNA, Fungal
  • DNA-Binding Proteins
  • DNL4 protein, S cerevisiae
  • LIF1 protein, S cerevisiae
  • LIG4 protein, human
  • Saccharomyces cerevisiae Proteins
  • DNA Ligases
  • DNA Ligase ATP