Human DNA polymerase beta is constitutively expressed in cells. It fills in gaps in DNA that are formed following base excision repair. 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. It conducts gap-filling DNA synthesis in a stepwise distributive fashion rather than in a processive fashion as for other DNA polymerases. The activity cannot be affected by Aphidicolin, which is an inhibitor of DNA polymerase beta.
