Replication of Rous sarcoma virus in synchronized cells.

When synchronized chicken embryo cells were infected with Rous sarcoma virus in the the G-I period of the cell cycle, virus replication was delayed by several hours compared with cells infected in the S period, and virus release began only after mitosis. The delay in replication was not due to a change in the rate of virus adsorption and penetration. There was no delay in replication of Newcastle disease virus, indicating that the cells in G-I were able to support replication of other RNA viruses. The shortest latent period for RSV (~2 to 14 hr) occurred when cells were infected between S and mitosis. The latent period increased for cells infected after the maximum of mitosis. Cells which had been in culture for more than ~ 5 hr rapidly lost their susceptibility to infection by RSV.