Fig. 2

Non-homologous end-joining DNA repair system. The general mechanism involves the recruitment of DNA dependent protein kinases (DNA-PK), following the attachment of Ku proteins on the broken ends of DNA. Afterward, a DNA polymerase fills the gaps that have been produced as a result of the endonuclease activity of Artemis protein. Finally, a DNA ligase IV joins the DNA ends with the help of its cofactors, XRCC4, and XLF