Poly (ADP-ribose) polymerase inhibits DNA replication by human replicative DNA polymerase alpha, delta and epsilon in vitro.
The influence of poly (ADP-ribose) polymerase (PARP) and poly ADP-ribosylation on DNA synthesis supported by human replicative DNA polymerase (DNA pol) alpha, delta, and epsilon has been examined using the replication system containing poly(dA)4500-oligo(dT)12-18 as the template primer. PARP alone inhibited the pol activities in a dose-dependent manner even in the presence of the accessory factors for DNA pol delta, proliferating cell nuclear antigen (PCNA) and activator 1 (Al; RF-C). Both DNA pol alpha and epsilon activities were decreased approximately 10-fold under the poly ADP-ribosylating condition. In contrast, DNA synthesis by DNA pol delta holoenzyme was not affected by poly ADP-ribosylation like prokaryotic DNA pol's. The analysis of poly(dT) formed by DNA pol alpha and epsilon indicated that poly ADP-ribosylation mainly reduced the frequency of replication. These observations suggest a possibility that PARP acts as a negative regulator for the initiation of DNA replication upon cellular DNA damage.
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Division of Human Genome Research and Gene Bank, Tsukuba Life Science Center, Ibaraki, Japan.
D004257:DNA Polymerase II / Q000378:metabolism*; D004258:DNA Polymerase III; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D011064:Poly Adenosine Diphosphate Ribose / Q000096:biosynthesis; D011065:Poly(ADP-ribose) Polymerases / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D013698:Templates, Genetic
D011064:Poly Adenosine Diphosphate Ribose; D011065:Poly(ADP-ribose) Polymerases; D004257:DNA Polymerase II; D004258:DNA Polymerase III; D004259:DNA-Directed DNA Polymerase