Abstract
Using an MLg cell line originating from a single newborn ddY mouse, N-tropic C-type virus able to infect the cells of origin was induced by 5-iodo-2'-deoxyuridine (IUdR). All the clones isolated from the MLg cell line released the virus after IUdR-treatment. There was more than a 100-fold difference in the virus inducibility between the highly and lowly inducible clones. The [125I]-IUdR incorporation was, however, the same for the both types of clones.
When the induced virus was titrated in the S + L - C182 cells, the XC plaque titre was about tenfold higher than murine sarcoma virus rescue focus titre.