Inhibition of RNA-dependent DNA polymerase activity of oncornaviruses by caffeine.

Abstract Caffeine was found to inhibit RNA-dependent DNA polymerase activity of Rauscher leukemia virus when endogenous viral RNA and poly(rA)·(dT) 12–18 were used as templates. Similar results were also obtained with purified RNA-dependent DNA polymerase (deoxynucleoside triphosphate; DNA nucleotidyl transferase; EC 2.7.7.7) from avian myeloblastosis virus (AMV) utilizing 70S and 35S RNA of AMV, poly(rA)·(dT) 12–18 , globin mRNA and activated calf thymus DNA as templates. The “caffeine effect” was evident only when it was present during the initiation of polymerization reaction. Increasing the template concentration in the reaction mixture partly reversed the effect of caffeine. Of the analogs of caffeine tested, only theophylline inhibited AMV DNA polymerase, whereas aminophylline showed no effect.