Utilization efficiency of the oxidized purine nucleotide analogs by DNA polymerase eta.

To elucidate the behavior of DNA polymerase eta against the oxidized purine nucleotides, we determined the utilization efficiency of 2-hydroxy-dATP and 8-hydroxy-dGTP by the recombinant yeast DNA polymerase eta using the primer extension assay with the synthetic oligonucleotide template-primers, and compared those by DNA polymerase alpha. Results indicate that DNA polymerase eta incorporates 2-hydroxy-dATP opposite template G in addition to template T and 8-hydroxy-dGTP opposite A in addition to C, respectively. Kinetic analysis revealed that the rate of mutation caused by 2-OH-dATP and 8-OH-dGTP with DNA polymerase eta should be much higher than those with DNA polymerase alpha.