Transformation of mammalian cells to antibiotic resistance with a bacterial gene under control of the SV40 early region promoter.
A bacterial (neo) gene conferring resistance to neomycin-kanamycin antibiotics has been inserted into SV40 hybrid plasmid vectors and introduced into cultured mammalian cells by DNA transfusion. While normal cells die with the antibiotic G418, those that acquire and express neo continue to grow in the presence of G418.
In the course of selection, neo DNA associates with high molecular weight cellular DNA and is retained even when cells are grown in the absence of G418 for prolonged periods. Since neo provides a marker for dominant selections, cellular transformation to G418 resistance is an efficient means for cotransformation of unselected genes.