Role of Proximal Promoter Elements in Regulation of Renin Gene Transcription
| Autor: | J. Pablo Abonia, Colleen M. Kane, Curt D. Sigmund, Kenneth W. Gross, John R. Fabian, Nenad Petrovic, Craig A. Jones, Thomas A. Black, John A. Loudon |
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| Rok vydání: | 1996 |
| Předmět: |
Transcription
Genetic Molecular Sequence Data Response element Biology Transfection Binding Competitive Biochemistry Substrate Specificity Chloramphenicol acetyltransferase Mice Upstream activating sequence Genes Reporter Transcription (biology) Renin Animals Promoter Regions Genetic Enhancer Molecular Biology Transcription factor Regulation of gene expression Binding Sites Base Sequence Chromosome Mapping Nuclear Proteins Promoter Cell Biology Molecular biology Gene Expression Regulation Electrophoresis Polyacrylamide Gel |
| Zdroj: | Journal of Biological Chemistry. 271:22499-22505 |
| ISSN: | 0021-9258 |
| Popis: | Mouse As4.1 cells, obtained after transgene-targeted oncogenesis to induce neoplasia in renal renin-expressing cells, express high levels of renin mRNA from the endogenous Ren-1(c) gene. We have used these cells to characterize the role of the Ren-1(c) proximal promoter (+6 to -117) in the regulation of renin gene transcription. It was found that 4.1 kilobases (kb) of Ren-1(c) 5'-flanking sequence, in combination with the proximal promoter, are required for strong activation (approximately 2 orders of magnitude over the basal level of the promoter alone) of the chloramphenicol acetyltransferase reporter in transfection assays. Within the 4.1-kb fragment, a 241-base pair region was identified that retains full activity in an orientation-independent manner in combination with the promoter. The resulting transcripts initiate at the normal renin start site. Electrophoretic mobility shift assays identified a sequence at approximately position -60 in the promoter region that binds nuclear proteins specific for renin-expressing As4.1 cells. Mutations in this sequence, which disrupt binding of nuclear protein(s), completely abolish activation of transcription by the 4. 1-kb fragment. Activation of transcription by the 241-base pair enhancer was still observed, although it was diminished in magnitude (60-fold over the mutated promoter alone). We present a model derived from the current data that suggests that regulation of renin expression is achieved through cooperation of transcription factors binding at the proximal promoter element and a distal enhancer element to abrogate or override the effects of an intervening negative regulatory region. |
| Databáze: | OpenAIRE |
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