DNA polymerase beta can substitute for DNA polymerase I in the initiation of plasmid DNA replication.
We previously demonstrated that mammalian DNA polymerase beta can substitute for DNA polymerase I of Escherichia coli in DNA replication and in base excision repair. We have now obtained genetic evidence suggesting that DNA polymerase beta can substitute for E. coli DNA polymerase I in the initiation of replication of a plasmid containing a pMB1 origin of DNA replication. Specifically, we demonstrate that a plasmid with a pMB1 origin of replication can be maintained in an E. coli polA mutant in the presence of mammalian DNA polymerase beta. Our results suggest that mammalian DNA polymerase beta can substitute for E. coli DNA polymerase I by initiating DNA replication of this plasmid from the 3' OH terminus of the RNA-DNA hybrid at the origin of replication.
Sweasy
J B
JB
Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Chen
M
M
Loeb
L A
LA
D000668:Ampicillin Resistance / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D004256:DNA Polymerase I / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010957:Plasmids / Q000096:biosynthesis*; D013045:Species Specificity
D004256:DNA Polymerase I