The cell-specific enhancer of the mouse transthyretin (prealbumin) gene binds a common factor at one site and a liver-specific factor(s) at two other sites.

摘要: We previously defined two distinct cell-specific DNA elements controlling the transient expression of transthyretin gene in Hep G2 (human hepatoma) cells: a proximal promoter region (-202 base pairs [bp] to cap site), and far-upstream enhancer located between 1.6 2.15 kilobases (kb) 5' site (R. H. Costa, E. Lai, J. Darnell, Jr., Mol. Cell. Biol. 6:4697-4708, 1986). In this report, we effective element within 100-bp 1.96 1.86 kb mRNA site. nuclear extracts, three protein-binding sites minimal were identified by gel mobility methylation protection experiments. Each binding was required for full activity assays. Competition experiments assays suggested that recognized similar factor protein interaction with third different. The protein(s) which bound homologous found mainly or only cells hepatic origin, suggesting an involvement function enhancer. recognizing also HeLa spleen cells.