Abstract
CV1, BSC1, Vero, and primary monkey kidney cells were seeded either at low cell density and infected with poliovirus while growing, or at high cell density and infected under conditions of contact inhibition. Virus RNA synthesis and virus production were delayed in the cells seeded at high cell density, although neither adsorption nor uncoating of the parental virus particles were altered. In spite of the delay, however, virus RNA synthesis, once initiated, proceeded in the same fashion and at the same rate in both growing and resting cells. This implies that one of the first events following uncoating of the infecting virus was temporarily retarded in resting cells. There are indications that this delay might be due to a lag in the formation of parental virus polyribosomes.