Fig. 4

The major DNA repair pathways involved in correcting DNA damage induced by oxidative stress. BER is the predominant repair mechanism that removes oxidative DNA damage to bases, via two general pathways—short-patch and long-patch. Short-patch BER facilitates repair of a single nucleotide, whereas long-patch BER repairs two or more nucleotides. Although the nucleus is the main subcellular localisation where BER takes place, it has also been detected in mitochondria [163]. NER is the principal pathway responsible for the removal of large single-stranded DNA adducts induced by UV irradiation, environmental mutagens, or chemotherapeutic agents, but it is also implicated in repairing oxidative DNA damage. MMR is another pathway that repairs DNA damage induced by oxidative stress. MMR is responsible for the detection and repair of errors produced during DNA replication, involving the incorrect insertion, deletion or misincorporation of nucleotides. RPA Replication protein A; pol δ DNA polymerase δ; Exo1 exonuclease 1