title: Passage of X-ray-induced immortal, non-transformed phenotype by DNA-mediated transfection.
abstract: To better understand the molecular basis of X-ray-induced carcinogenesis, the immortalization step of this multistep process was examined. Primary rat embryo cells were X-irradiated in vitro and six clones were isolated. Three of these, one designated X-REF-23, were immortal and non-transformed. Transfection of high molecular weight DNA from rat X-REF-23 cells into primary mouse cells yielded two immortal and non-transformed mouse clones, 1K and 2I. Using a 2.3 kb rat-specific repetitive sequence as probe, 1K and 2I were demonstrated to contain rat DNA. This transfected DNA was not any of the known immortalization-associated proto-oncogenes. DNA from 1K was then transfected into primary mouse cells, with or without co-transfection of pSV2 neo DNA. Six immortal mouse clones were isolated and confirmed to contain rat sequences. In conclusion, the immortal phenotype can be transferred by DNA transfection.
authors.affiliation: Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: C K
authors.initials: CK
authors.lastname: Too
authors.forename: E
authors.initials: E
authors.lastname: Sierra-Rivera
authors.forename: L W
authors.initials: LW
authors.lastname: Oberley
authors.forename: D L
authors.initials: DL
authors.lastname: Guernsey
mesh_terms: D000818:Animals; D002455:Cell Division; D004247:DNA / Q000528:radiation effects*; D051379:Mice; D009857:Oncogenes; D010641:Phenotype; D051381:Rats; D014162:Transfection; D014965:X-Rays
chemical_list: D004247:DNA