title: Purified plasma membranes inhibit polypeptide growth factor-induced DNA synthesis in subconfluent 3T3 cells.
abstract: Plasma membranes derived from NR-6 cells, a variant line of Swiss mouse 3T3 cells that does not have cell surface receptors for epidermal growth factor (EGF), inhibited EGF-induced stimulation of DNA synthesis by 50% in serum-starved, subconfluent 3T3 cells. Membranes derived from SV3T3 cells were much less effective in inhibiting EGF-induced DNA synthesis. This inhibition on DNA synthesis by NR-6 membranes was not a direct effect of membranes on EGF, nor could it be overcome by high concentrations of EGF. NR-6 membranes were most effective when added 3 h before EGF addition and had little effect when added 2 h or more after EGF. NR-6 membranes also reduced the stimulation of DNA synthesis induced by platelet-derived growth factor or fibroblast growth factor in serum-starved 3T3 cells. These findings indicate that membrane-membrane interactions between nontransformed cells may diminish their ability to proliferate in response to serum polypeptide growth factors.
mesh_terms: D000818:Animals; D002453:Cell Cycle; D002462:Cell Membrane / Q000502:physiology*; D002478:Cells, Cultured; D003260:Contact Inhibition; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D006131:Growth Inhibitors; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology
chemical_list: D006131:Growth Inhibitors; D010982:Platelet-Derived Growth Factor; D005346:Fibroblast Growth Factors; D004815:Epidermal Growth Factor