Vol 49(2015) N 1 p. 58-64; DOI 10.1134/S0026893315010070
A.A. Kosova1, O.I. Lavrik1,2, S.N. Khodyreva1,2*
Role of Ku antigen in the repair of apurinic/apyrimidinic sites in DNA
1Institute of Chemical Biology and Fundamental Medicine, Siberian Division of Russian Academy of Sciences,Novosibirsk, 630090 Russia
Apurinic/apyrimidinic (AP) sites are some of the most frequent lesions in genomic DNA. It is widely accepted that, regardless of their origin, AP sites are further processed by base excision repair (BER) machinery, being the central intermediate of this process. Proteins that recognize AP sites are able to form covalent adducts with DNA under special conditions. Using a combination of the crosslinking technique with mass-spectrometry analysis, Ku antigen (Ku) (the central player in nonhomologous end joining (NHEJ), which is the pathway of double-strand break (DSB) repair), was identified as a protein reactive to AP sites. Moreover, Ku was shown to be 5'-dRP/AP lyase, which acts near DSBs in NHEJ. Recent studies have demonstrated the involvement of Ku in the different stages of BER. Here, Ku functions in the NHEJ and BER pathways of DNA repair were overviewed.
Ku antigen, apurinic/apyrimidinic site, nonhomologous end joining, base excision repair