Cell Cycle Position and Expression of Encephalomyocarditis Virus in Mouse Embryo Fibroblasts

Infection of mouse embryo fibroblasts in G₁ or S phase with encephalomyocarditis virus gave different kinetics of viral RNA synthesis. In S phase cells, RNA synthesis was faster and reached higher levels than in G₁ cells. Virus-specified proteins were fewer in G₁ cells than in S cells during the early stage of the infection and c.p.e. in G₁ cells appeared about 4 h later than in S cells. Addition of a cellular factor with ability to affect cell conformation had an inhibitory effect on viral RNA synthesis.