DNA polymerase activity associated with RNA tumor viruses.

C-type RNA viruses, originating in mouse, cat, hamster, and viper, catalyze the synthesis of DNA from its constituent deoxyribonucleoside triphosphates. Both the rate and extent of the reaction were significantly enhanced by brief treatment of the intact virus with ether. A proportion of the newly synthesized DNA was associated with virions when intact virus was used as template; this was not the case with ether-treated virus. In both cases, DNA extracted from the reaction mixture sedimented slowly, at about 2-4 S.