Autor: |
Jessica S. Williams, Jessica L. Wojtaszek, Denise C. Appel, Juno Krahn, Bret D. Wallace, Evan Walsh, Thomas A. Kunkel, R. Scott Williams |
Jazyk: |
angličtina |
Rok vydání: |
2022 |
Předmět: |
|
Zdroj: |
Cell Reports, Vol 41, Iss 1, Pp 111448- (2022) |
Druh dokumentu: |
article |
ISSN: |
2211-1247 |
DOI: |
10.1016/j.celrep.2022.111448 |
Popis: |
Summary: Topoisomerase 1 (Top1) incises DNA containing ribonucleotides to generate complex DNA lesions that are resolved by APE2 (Apn2 in yeast). How Apn2 engages and processes this DNA damage is unclear. Here, we report X-ray crystal structures and biochemical analysis of Apn2-DNA complexes to demonstrate how Apn2 frays and cleaves 3′ DNA termini via a wedging mechanism that facilitates 1–6 nucleotide endonucleolytic cleavages. APN2 deletion and DNA-wedge mutant Saccharomyces cerevisiae strains display mutator phenotypes, cell growth defects, and sensitivity to genotoxic stress in a ribonucleotide excision repair (RER)-defective background harboring a high density of Top1-incised ribonucleotides. Our data implicate a wedge-and-cut mechanism underpinning the broad-specificity Apn2 nuclease activity that mitigates mutagenic and genome instability phenotypes caused by Top1 incision at genomic ribonucleotides incorporated by DNA polymerase epsilon. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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