DNA polymerase e catalytic domains are dispensable for DNA replication, DNA repair, and cell viability

DNA polymerase ε (Pol ε) is believed to play an essential catalytic role during eukaryotic DNA replication and is thought to participate in recombination and DNA repair. That Pol ε is essential for progression through S phase and for viability in budding and fission yeasts is a central element of support for that view. We show that the amino-terminal portion of budding yeast Pol ε (Pol2) containing all known DNA polymerase and exonuclease motifs is dispensable for DNA replication, DNA repair, and viability. However, the carboxy-terminal portion of Pol2 is both necessary and sufficient for viability. Finally, the viability of cells lacking Pol2 catalytic function does not require intact DNA replication or damage checkpoints.