External and internal DNA-damaging agents continually
threaten the integrity of genetic material in cells. Although a
variety of repair mechanisms exist to remove the resulting lesions,
some lesions escape repair and block the replication machinery.
Members of the Y family of DNA polymerases, such as POLK, permit
the continuity of the replication fork by allowing replication
through such DNA lesions. Each Y family polymerase has a unique
DNA-damage bypass and fidelity profile. POLK is specialized for the
extension step of lesion bypass (summary by Lone et al., 2007
[PubMed 17317631]).
