title: Retransformation of a simian virus 40 revertant cell line, which is resistant to viral and DNA infections, by microinjection of viral DNA.
abstract: We have isolated morphological transformants of cultured cells as dense foci on a monolayer of normal cells appproximately 4 weeks after microinjection of purified simian virus 40 DNA (200 to 400 molecules per cell) directly into the nucleus. Both Rat 1 (an established contact-inhibited rat embryo fibroblast line) and F1' 1--4 (a 5-fluorodeoxyuridine-selected flat revertant from the simian virus 40-transformed 14B cell line) were transformed with an efficiency of 5 to 10% of the cells injected. F1' 1--4 is not susceptible to retransformation by either viral or DNA infection (by calcium phosphate-facilitated cellular uptake), and as a result it had previously been thought to possess a host mutation preventing expression of the simian virus 40 genome.
mesh_terms: D000818:Animals; D000956:Antigens, Viral; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002472:Cell Transformation, Viral; D004279:DNA, Viral / Q000235:genetics*; D008845:Microinjections; D051381:Rats; D013539:Simian virus 40 / Q000254:growth & development / Q000276:immunology; D014162:Transfection
chemical_list: D000956:Antigens, Viral; D004279:DNA, Viral