Suppression of the transformed phenotype with retention of the viral ‘ src’ gene in cell hybrids between rous sarcoma virus-transformed rat cells and untransformed mouse cells

Abstract

Hybrid cell lines between untransformed mouse 3T3TK-cells and normal rat kidney (NRK) cells transformed by the B77 strain of Rous Sarcoma Virus (RSV) express a non-transformed phenotype, as determined by anchorage-dependent growth and organization of microfilament bundles. Virus rescue experiments and genetic experiments using an RSV mutant temperature-sensitive for maintenance of the transformed phenotype demonstrate that RSV is retained in the non-transformed hybrids. The action of the viral transformation gene ‘ src’ therefore appears to be ‘suppressed’ in these hybrids. The suppressed hybrids generate variants in which the expression of the transformed phenotype and the ‘ src’ gene is regained. This system should prove to be of value in identifying cellular genes involved in the expression of virally induced transformation.