Catalytic component of the DNA polymerase epsilon complex which participates in chromosomal DNA replication (PubMed:1537345). Required during synthesis of the leading DNA strands at the replication fork, binds at/or near replication origins and moves along DNA with the replication fork (PubMed:31488849). Has 3'-5' proofreading exonuclease activity that corrects errors arising during DNA replication (PubMed:12124389). a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) Binds 1 [4Fe-4S] cluster. DNA polymerase epsilon is a heterotetramer consisting of POL2, DPB2, DPB3 and DPB4. The DNA polymerase activity domain resides in the N-terminal half of the protein, while the C-terminus is necessary for complexing subunits B and C. The CysA-type zinc finger is required for PCNA-binding. The CysB motif binds 1 4Fe-4S cluster and is required for the formation of polymerase complexes. In eukaryotes there are five DNA polymerases: alpha, beta, gamma, delta, and epsilon which are responsible for different reactions of DNA synthesis. Present with 1970 molecules/cell in log phase SD medium. Belongs to the DNA polymerase type-B family.