Inhibition of a novel subspecies of DNA polymerase α by 2′-deoxy-2′-azidoadenosine 5′-triphosphate

Abstract

DNA polymerase α 1, a subspecies of DNA polymerase α of Ehrlich ascites tumor cells, was associated with a novel RNA polymerase activity and utilized poly(dT) and single-stranded circular fd DNA as a template without added primer in the presence of ribonucleoside triphosphates and a specific stimulating factor. DNA synthesis in the above system was inhibited by the ATP analogue, 2′-deoxy-2′-azidoadenosine 5′-triphosphate more than the DNA synthesis with poly(dT)·oligo(rA) by DNA polymerase α 1 and RNA synthesis by mouse RNA polymerases I and II. Kinetic analysis showed that the analogue inhibited DNA polymerase α 1 activity on poly(dT) competitively with respect to ATP, suggesting that the analogue inhibited RNA synthesis by the associated RNA polymerase activity.