Tissue-specificin vivoprotein-DNA interactions at the promoter region of theXenopus63 kDa keratin gene during metamorphosis
| Autor: | Leo Miller, David Warshawsky |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Cell Membrane Permeability
Transcription Genetic Sp1 Transcription Factor Xenopus Molecular Sequence Data DNA Footprinting DNA footprinting Xenopus Proteins Biology Polymerase Chain Reaction DNA-binding protein Species Specificity Keratin Genetics Animals Humans Tissue Distribution Binding site Promoter Regions Genetic Transcription factor Gene chemistry.chemical_classification Sp1 transcription factor Binding Sites Base Sequence integumentary system Metamorphosis Biological Promoter TATA Box Molecular biology Up-Regulation DNA-Binding Proteins Transcription Factor AP-2 chemistry Keratins Triiodothyronine Epidermis HeLa Cells Protein Binding Transcription Factors |
| Zdroj: | Nucleic Acids Research. 23:4502-4509 |
| ISSN: | 1362-4962 0305-1048 |
| DOI: | 10.1093/nar/23.21.4502 |
| Popis: | The Xenopus 63 kDa keratin gene is developmentally regulated and is expressed only in the epidermis. Full activation of the 63 kDa keratin gene requires two regulatory steps, the first independent and the second dependent on the thyroid hormone triiodothyronine (T3). Sequence analysis of a genomic clone of the 63 kDa keratin gene identified potential AP2 and SP1 binding sites upstream of the transcription initiation site. Electrophoretic mobility shift assays using purified or enriched proteins, as well as HeLa nuclear extract in conjunction with AP2- and SP1-specific antibodies, have been used to demonstrate that human AP2 and SP1 bind elements upstream of the transcription initiation site. In vivo footprinting with ligation mediated PCR revealed several footprints, within 350 bp upstream of the transcription initiation site, including those at the AP2 and SP1 sites, that are unique to epidermal cells which express the keratin gene. These footprints were absent in blood cells and XL177 cells which do not express the gene. Comparison of footprints between cells which express the 63 kDa keratin gene at low or high levels showed that the same binding sites are occupied, indicating that these sites are required for basal as well as T3-induced expression of the 63 kDa keratin gene. |
| Databáze: | OpenAIRE |
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