Steroid RU 486 inducible myogenesis by 10T1/2 fibroblastic mouse cells

For reconstruction or repair of damaged tissues, an artificially regulated switch from proliferation to differentiation would be of great advantage. T o achieve conditional myogenesis, we expressed MyoD in mouse C3H 10T1/2 fib roblastic cells, using a gene regulation system based on the synthetic ster oid RU 486, BS stable co-transfection of a plasmid construct with the RU 48 6 dependent activator and an integrating inducible MyoD construct, a cell c lone, designated 10T-RM, was obtained in which MyoD expression was stringen tly controlled by RU 486, 12 h after addition of 10 nM RU 486 to 10T-RM cel ls, saturation levels of MyoD mRNA were observed and greater than or equal to 2 days later, mRNA for embryonal myosin heavy chain (MyHC(emb)) was abun dant and mononucleated cells fused into myotubes. (C) 2000 Federation of Eu ropean Biochemical Societies.