A new proofreading mechanism for lesion bypass by DNA polymerase-?.
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ABSTRACT:
SUBMITTER: Crespan E
PROVIDER: S-EPMC3246252 | biostudies-literature | 2011 Dec
REPOSITORIES: biostudies-literature
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A new proofreading mechanism for lesion bypass by DNA polymerase-λ.
Crespan Emmanuele E Maga Giovanni G Hübscher Ulrich U
EMBO reports 20111223 1
Replicative DNA polymerases (DNA pols) increase their fidelity by removing misincorporated nucleotides with their 3' → 5' exonuclease activity. Exonuclease activity reduces translesion synthesis (TLS) efficiency and TLS DNA pols lack 3' → 5' exonuclease activity. Here we show that physiological concentrations of pyrophosphate (PP(i)) activate the pyrophosphorolytic activity by DNA pol-λ, allowing the preferential excision of the incorrectly incorporated A opposite a 7,8-dihydro-8-oxoguanine lesi ...[more]
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