title: Generation of myc/fos transfectant Balb-3T3 cell lines.
abstract: Early and transient expression of proto-oncogenes c-fos and c-myc is involved in the mitogenic response to PDGF (platelet-derived growth factor). We used DNA-mediated transfection to approach the role played by these genes in cell growth control by PDGF and in growth deregulation (neoplasia). Cloned pFBJ-2 (v-fos) and glucocorticoid-inducible mouse c-myc were co-transfected with a neo genetic marker to allow a neutral selection on the basis of resistance to the neomycin derivative geneticin G418. pFBJ-2 transfection was found to interfere with the number of G418-resistant (G418r) colonies. By using a v-fos-deleted pFBJ-2 construct, the deleterious effect was attributed to v-fos coding sequences. Cellular fos gene disruption, by homologous recombination with exogenous v-fos, is proposed as the basis for the deleterious effect. Co-transfection with MMTV-H3-c-myc effectively counteracts the negative effects of v-fos. Different from the parental line or single myc or fos transfectants, double myc/fos transfectants are morphologically transformed. Double transfectants still retain the PDGF requirement for growth in monolayer cultures.
authors.affiliation: Instituto de Química, Universidade de Sao Paulo, Brasil.
authors.forename: M C
authors.initials: MC
authors.lastname: Armelin
authors.forename: C A
authors.initials: CA
authors.lastname: Joazeiro
authors.forename: K M
authors.initials: KM
authors.lastname: Rocha
authors.forename: H A
authors.initials: HA
authors.lastname: Armelin
mesh_terms: D000818:Animals; D002460:Cell Line; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000502:physiology; D011519:Proto-Oncogenes; D014162:Transfection
chemical_list: D010982:Platelet-Derived Growth Factor