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DNA polymerase η contributes to lagging strand synthesis

ABSTRACT: DNA polymerase eta (pol eta) is best known for its ability to bypass UV-induced thymine-thymine (T-T) dimers and other bulky DNA lesions, but pol eta also has other cellular roles. Here, we present evidence that pol eta competes with DNA polymerases alpha and delta for the synthesis of the lagging strand genome-wide, where it also shows a preference for T-T in the DNA template. Moreover, we found that the C-terminus of pol eta which contains a PCNA-Interacting Protein motif is required for pol eta to function in lagging strand synthesis. Finally, we provide evidence that a pol η dependent signature is also found to be lagging strand specific in patients with skin cancer. Taken together, these findings provide insight into the physiological role of DNA synthesis by pol eta and have implications for our understanding of how our genome is replicated to avoid mutagenesis, genome instability and cancer.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE110241 | GEO | 2018/12/14

REPOSITORIES: GEO

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DNA polymerase η contributes to lagging strand synthesis

Project description:DNA polymerase η contributes to lagging strand synthesis

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