Uncoupled expression of mRNAs for α1(I) and α2(I) procollagen chains in chemically transformed Syrian hamster fibroblasts

Abstract

Syrian hamster embryo fibroblasts transformed by 4-nitroquinoline-1-oxide (NQT-SHE cells) failed to synthesize the pro-α1(I) subunit of type I procollagen but continued to synthesize altered forms of the other subunit, pro-α2(I) (Peterkofsky, B., and Prather, W. (1986) J. Biol. Chem. 261, 16818-16826). This was unusual, since synthesis of the two subunits generally is coordinately regulated. Present experiments using cell-free translation and hybridization of RNA from normal and transformed Syrian hamster fibroblasts with labeled pro-α1(I) DNA probes show that mRNA for pro-α1(I) is absent from the transformant. In contrast, dot-blot and Southern blot hybridizations of cellular DNAs with pro-..