Genetic transformation of mouse cultured cells with the help of high‐velocity mechanical DNA injection

Abstract
NIH 3T3 mouse cells were transfected by the plasmid pSV3neo (G418‐resistant) with the help of high‐velocity mechanical DNA injection based on the principle of bombarding cells with tungsten particles covered with the DNA. Stable transformants were obtained. Dot‐hybridization and Southern analysis revealed the integration into the genome of 5–20 copies per cell of original plasmid DNA. The plasmid DNA was shown to have tandem organization.