The enhancer of the human transferrin gene is organized in two structural and functional domains.

摘要: We previously identified a 300-base pair long enhancer, located 3.6 kilobases upstream of the cap site human transferrin gene. A 5' deletion up to position 86 enhancer resulted in complete loss activity. Here we show by competition footprint analysis, gel retardation assays, and transient expression studies hepatoma HeLa cells that is composed two distinct structural functional domains, (nucleotides 1-86) B 87-291). Each domain proto-enhancer different type. Domain that, when multimerized, able itself stimulate transcription from heterologous SV40 promoter, both Hep3B cells. It contains octanucleotide TGTTTGCT sequence binding liver-specific nuclear factors factor. four sites interacting with several liver proteins. In order bind, any these proteins requires presence all others. This block activity downstream negative element, but it has no itself. full association domains B.