Aphidicolin: an inhibitor of DNA repair in human fibroblasts

Abstract

Aphidicolin is a specific inhibitor of DNA polymerase α. Its influence on DNA repair has been studied in both normal and excision deficient xeroderma pigmentosum cells exposed to u.v. irradiation at 254 nm. Single strand DNA breaks accumulated in u.v. irradiated normal cells when the inhibitor was present. Such breaks were absent in both unirradiated normal cells and in u.v. irradiated excision deficient cells incubated with the compound. The data therefore indicate that aphidicolin prevents the rejoining of single strand breaks formed during the excision repair process and imply that DNA polymerase a is involved in the repair of DNA in human cells.