We have used inhibitors to identify the DNA polymerases which are involved in DNA excision repair induced in confluent diploid human fibroblasts by several DNA damaging agents: UV radiation, N-acetoxy-2-acetylaminofluorene, N-methyl-N-nitrosourea, and bleomycin. We find that DNA repair synthesis involves both DNA polymerase α and a non-α DNA polymerase, probably polymerase β. The fraction of repair synthesis mediated by each of the two polymerases is dependent on which DNA-damaging agent is administered and on the dose of damaging agent. Low doses of DNA damage induce DNA repair synthesis which is mediated to a great extent by a non-α DNA polymerase, and with an increasing dose of damage there is increasing participation of DNA polymerase α in repair synthesis. At high doses of damage, the fraction of repair synthesis mediated by DNA polymerase α reaches a maximal level which is dependent on the damaging agent; the maximal level of polymerase α involvement is about 80% for UV radiation and N-acetoxy-2-acetylaminofluorene, about 70% for N-methyl-N-nitrosourea, and about 40% for bleomycin.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Biological Chemistry|
|State||Published - 1983|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology