Article

DNA polymerases provide a canon of strategies for translesion synthesis past oxidatively generated lesions

Department of Microbiology and Molecular Genetics, The Markey Center for Molecular Genetics, University of Vermont, Burlington, VT 05405, USA.
Current Opinion in Structural Biology (Impact Factor: 8.75). 06/2011; 21(3):358-69. DOI: 10.1016/j.sbi.2011.03.008
Source: PubMed

ABSTRACT Deducing the structure of the DNA double helix in 1953 implied the mode of its replication: Watson-Crick (WC) base pairing might instruct an enzyme, now known as the DNA polymerase, during the synthesis of a daughter stand complementary to a single strand of the parental double helix. What has become increasingly clear in the last 60 years, however, is that adducted and oxidatively generated DNA bases are ubiquitous in physiological DNA, and all organisms conserve multiple DNA polymerases specialized for DNA synthesis opposite these damaged templates. Here, we review recent crystal structures depicting replicative and bypass DNA polymerases encountering two typical lesions arising from the oxidation of DNA: abasic sites, which block the replication fork, and the miscoding premutagenic lesion 7,8-dihydro-8-oxoguanine (8-oxoG).

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Sylvie Doublie