DNA polymerase delta subunit 4 (POLD4)

As a part of the tetrameric DNA polymerase delta complex (Pol-delta4), plays a role in high fidelity genome replication and repair. Within this complex, increases the rate of DNA synthesis and reduces fidelity by regulating POLD1 polymerase and proofreading 3' to 5' exonuclease activity (PubMed:16510448, PubMed:19074196, PubMed:20334433).

Pol-delta4 participates in Okazaki fragment processing, through both the short flap pathway, in addition to a nick translation system (PubMed:24035200). Under conditions of DNA replication stress, required for the treatment of broken replication forks through break- induced replication (BIR), a mechanism which may induce segmental genomic duplications of up to 200 kb (PubMed:24310611).