Bifunctional polynucleotide phosphatase/kinase; Plays a key role in the repair of DNA damage, functioning as part of both the non-homologous end-joining (NHEJ) and base excision repair (BER) pathways. Through its two catalytic activities, PNK ensures that DNA termini are compatible with extension and ligation by either removing 3’-phosphates from, or by phosphorylating 5’-hydroxyl groups on, the ribose sugar of the DNA backbone; HAD Asp-based non-protein phosphatases (521 aa)

DNA polymerase beta; Repair polymerase that plays a key role in base-excision repair. Has 5’-deoxyribose-5-phosphate lyase (dRP lyase) activity that removes the 5’ sugar phosphate and also acts as a DNA polymerase that adds one nucleotide to the 3’ end of the arising single-nucleotide gap. Conducts ’gap-filling’ DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases (335 aa)

TFIIH basal transcription factor complex helicase XPD subunit; ATP-dependent 5’-3’ DNA helicase, component of the core- TFIIH basal transcription factor. Involved in nucleotide excision repair (NER) of DNA by opening DNA around the damage, and in RNA transcription by RNA polymerase II by anchoring the CDK-activating kinase (CAK) complex, composed of CDK7, cyclin H and MAT1, to the core-TFIIH complex. Involved in the regulation of vitamin-D receptor activity. As part of the mitotic spindle-associated MMXD complex it plays a role in chromosome segregation. Might have a role in aging proc [...] (760 aa)

Aprataxin and PNK-like factor; Nuclease involved in single-strand and double-strand DNA break repair. Recruited to sites of DNA damage through interaction with poly(ADP-ribose), a polymeric post-translational modification synthesized transiently at sites of chromosomal damage to accelerate DNA strand break repair reactions. Displays apurinic- apyrimidinic (AP) endonuclease and 3’-5’ exonuclease activities in vitro. Also able to introduce nicks at hydroxyuracil and other types of pyrimidine base damage; Zinc fingers (511 aa)

Flap endonuclease 1; Structure-specific nuclease with 5’-flap endonuclease and 5’-3’ exonuclease activities involved in DNA replication and repair. During DNA replication, cleaves the 5’-overhanging flap structure that is generated by displacement synthesis when DNA polymerase encounters the 5’-end of a downstream Okazaki fragment. It enters the flap from the 5’-end and then tracks to cleave the flap base, leaving a nick for ligation. Also involved in the long patch base excision repair (LP-BER) pathway, by cleaving within the apurinic/apyrimidinic (AP) site-terminated flap. Acts as a [...] (380 aa)

Endonuclease 8-like 1; Involved in base excision repair of DNA damaged by oxidation or by mutagenic agents. Acts as DNA glycosylase that recognizes and removes damaged bases. Has a preference for oxidized pyrimidines, such as thymine glycol, formamidopyrimidine (Fapy) and 5-hydroxyuracil. Has marginal activity towards 8- oxoguanine. Has AP (apurinic/apyrimidinic) lyase activity and introduces nicks in the DNA strand. Cleaves the DNA backbone by beta-delta elimination to generate a single-strand break at the site of the removed base with both 3’- and 5’-phosphates. Has DNA glycosylase/l [...] (390 aa)

Endonuclease 8-like 2; Involved in base excision repair of DNA damaged by oxidation or by mutagenic agents. Has DNA glycosylase activity towards 5-hydroxyuracil and other oxidized derivatives of cytosine with a preference for mismatched double-stranded DNA (DNA bubbles). Has low or no DNA glycosylase activity towards thymine glycol, 2-hydroxyadenine, hypoxanthine and 8-oxoguanine. Has AP (apurinic/apyrimidinic) lyase activity and introduces nicks in the DNA strand. Cleaves the DNA backbone by beta-delta elimination to generate a single-strand break at the site of the removed base with [...] (332 aa)

DNA polymerase delta catalytic subunit; As the catalytic component of the trimeric (Pol-delta3 complex) and tetrameric DNA polymerase delta complexes (Pol-delta4 complex), plays a crucial role in high fidelity genome replication, including in lagging strand synthesis, and repair. Exhibits both DNA polymerase and 3’- to 5’-exonuclease activities. Requires the presence of accessory proteins POLD2, POLD3 and POLD4 for full activity. Depending upon the absence (Pol-delta3) or the presence of POLD4 (Pol-delta4), displays differences in catalytic activity. Most notably, expresses higher proo [...] (1107 aa)