DNA Polymerase Mediates a Back-up Base Excision Repair Activity in Extracts of Mouse Embryonic Fibroblasts*
نویسندگان
چکیده
Mammalian DNA polymerase (pol) is a member of the X-family of DNA polymerases and has striking enzymatic and structural similarities to mammalian DNA pol . Because pol provides two important enzymatic activities for base excision repair (BER), we examined whether pol might also contribute to BER. We used extracts from mouse embryonic fibroblasts representing wild-type and null genotypes for pol and pol . In combination with neutralizing antibodies against pol and pol , our results show a BER deficiency in the pol / cell extract compared with extract from isogenic wild-type cells. In addition, the pol antibody strongly reduced in vitro BER in the pol / cell extract. These data indicate that pol is able to contribute to BER in mouse fibroblast cell extract.
منابع مشابه
DNA Polymerases β and λ Mediate Overlapping and Independent Roles in Base Excision Repair in Mouse Embryonic Fibroblasts
Base excision repair (BER) is a DNA repair pathway designed to correct small base lesions in genomic DNA. While DNA polymerase beta (pol beta) is known to be the main polymerase in the BER pathway, various studies have implicated other DNA polymerases in back-up roles. One such polymerase, DNA polymerase lambda (pol lambda), was shown to be important in BER of oxidative DNA damage. To further e...
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