Amino acid substitutions at conserved tyrosine 52 alter fidelity and bypass efficiency of human DNA polymerase eta.

DNA polymerase eta (Pol eta) is a member of a new class of DNA polymerases that is able to copy DNA containing damaged nucleotides. These polymerases are highly error-prone during copying of unaltered DNA templates. We analyzed the relationship between bypass efficiency and fidelity of DNA synthesis by introducing substitutions for Tyr-52, a highly conserved amino acid, within the human DNA polymerase eta (hPol eta) finger domain.