Newcastle disease virus complementary RNA: Its relationship to the viral genome and its accumulation in the presence or absence of actinomycin D

Abstract

Tritium-labeled RNA isolated from Newcastle disease virus (NDV) was annealed with RNA extracted from chick embryo cells incubated with or without 10 μg/ml actinomycin D for 7 hours after infection by NDV. By measurement of acid-precipitable radioactivity after ribonuclease treatment of annealed materials, it was found that at least 80% of the NDV genome is represented by complementary counterparts in infected cells whether or not the cells are incubated with actinomycin D. Specific dilution assays showed that actinomycin D enhanced accumulation of both NDV parental-type (+) RNA and NDV complementary (−) RNA in cells, but the drug did not lower the ratio of (+) to (−) RNA.