POLK

POLK is a member of the DNA polymerase type-Y family of proteins. The encoded protein is a specialized DNA polymerase that catalyzes translesion DNA synthesis, which allows DNA replication in the presence of DNA lesions. Human cell lines lacking a functional copy of this gene exhibit impaired genome integrity and enhanced susceptibility to oxidative damage. Mutations in this gene that impair enzyme activity may be associated with prostate cancer in human patients.

Full Name

POLK

Function

DNA polymerase specifically involved in DNA repair. Plays an important role in translesion synthesis, where the normal high-fidelity DNA polymerases cannot proceed and DNA synthesis stalls. Depending on the context, it inserts the correct base, but causes frequent base transitions, transversions and frameshifts. Lacks 3'-5' proofreading exonuclease activity. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but does not have lyase activity.

Biological Process

Cellular response to DNA damage stimulusManual Assertion Based On ExperimentIDA:UniProtKB
Cellular response to UVManual Assertion Based On ExperimentIDA:UniProtKB
DNA repairManual Assertion Based On ExperimentIDA:UniProtKB
DNA replicationIEA:UniProtKB-KW
Error-prone translesion synthesisManual Assertion Based On ExperimentIDA:UniProtKB
Nucleotide-excision repair, DNA gap fillingManual Assertion Based On ExperimentIMP:UniProtKB

Cellular Location

Nucleus
Detected throughout the nucleus and at replication foci (PubMed:12414988).
Recruited to DNA damage sites in response to ultraviolet irradiation: N6-methyladenosine (m6A)-containing mRNAs accumulate in the vicinity of DNA damage sites and their presence is required to recruit POLK (PubMed:28297716).