Intracellular Sites of Synthesis of Encephalomyocarditis Virus Components in Krebs-2 Ascites Tumour Cells

Abstract

SUMMARY: Ascites tumour cells were homogenized and fractionated at various times after infection with encephalomyocarditis virus in vitro. Infective ribonucleic acid (RNA) could be obtained from the nuclear fraction soon after infection and the amount of infective RNA recovered from this fraction increased until a maximum was reached at about 4 1/2 hr. From 4 1/2 hr. onwards the amount of infective RNA associated with the nuclear fraction fell while that from the mitochondrial fraction increased, reaching a maximum at about 5 1/2 hr. The amount of haemagglutinin and plaque-forming virus began to increase at about 4 1/2 hr. and continued to rise until 8 hr. Most of this virus activity was found in the mitochondrial fraction, although from 6 hr. onwards an increasing amount was found in the microsomal fraction.