Functional Interaction between Ku and the Werner Syndrome Protein in DNA End Processing

摘要: Werner syndrome (WS) is an autosomal recessive disease characterized by premature aging. The gene responsible for the was recently cloned and shown to encode a protein with strong homology DNA/RNA helicases. In addition, (WRN) possesses exonuclease activity. Based on helicases it has been proposed that WRN functions in some aspects of DNA replication, recombination, or repair. However, there currently no evidence role any these processes; therefore, its biological function remains unknown. Using biochemical approach, we have identified two polypeptides bind protein. Peptide sequence analysis indicates proteins are identical Ku70 Ku80, heterodimer involved double strand break repair non-homologous end joining. Protein-protein interaction studies reveal binds directly Ku80 this mediated amino terminus WRN. show binding Ku alters specificity exonuclease. These results suggest potential involvement breaks.