Abstract
Human DNA polymerase N (PolN) is an A-family nuclear DNA polymerase whose function is unknown. This study examines the possible role of PolN in DNA repair in human cells treated with PolN-targeted siRNA. HeLa cells with siRNA-mediated knockdown of PolN were more sensitive than control cells to DNA cross-linking agent mitomycin C (MMC) but were not hypersensitive to UV irradiation. The MMC hypersensitivity of PolN knockdown cells was rescued by the overexpression of DNA polymerase-proficient PolN but not by DNA polymerase-deficient PolN. Furthermore, in vitro experiments showed that purified PolN conducts low-efficiency nonmutagenic bypass of a psoralen DNA interstrand cross-link (ICL), whose structure resembles an intermediate in the proposed pathway of ICL repair. These results suggest that PolN might play a role in translesion DNA synthesis during ICL repair in human cells.
Original language | English (US) |
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Pages (from-to) | 11817-11824 |
Number of pages | 8 |
Journal | Biochemistry |
Volume | 48 |
Issue number | 49 |
DOIs | |
State | Published - Dec 15 2009 |
ASJC Scopus subject areas
- Biochemistry