Identification and characterization of a novel repressor site in the human tumor necrosis factor α gene

• Published in: Nucleic acids research Vol. 22; no. 6; pp. 1108 - 1114
• Main Authors: Fong, Chin-Lin W., Siddiqui, Ayesha H., Mark, David F.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 25.03.1994
• Subjects: Base Composition; Base Sequence; Binding Sites; Biological and medical sciences; Cell Line; DNA - chemistry; DNA - metabolism; DNA Mutational Analysis; DNA Probes; DNA-Binding Proteins - metabolism; Fundamental and applied biological sciences. Psychology; genes; Humans; identification; man; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Plasmids; Promoter Regions, Genetic; Regulatory Sequences, Nucleic Acid; Repressor Proteins - metabolism; repressors; sites; Tetradecanoylphorbol Acetate - pharmacology; Transcription. Transcription factor. Splicing. Rna processing; tumor necrosis factor- alpha; Tumor Necrosis Factor-alpha - genetics; Human; Regulation(control); Transcription promoter; Cytokine; Trans acting regulatory factor; Molecular interaction; Regulatory sequence; Mutation; Repression; Gene expression; Tumor necrosis factor α
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/22.6.1108

In human monocytic cell lines, tumor necrosis factor α (TNFα) expression is induced by phorbol myrlstate acetate (PMA). We have identified positive and negative cls-acting elements in the TNFα promoter by deletion analysis. Here we present the initial characterization of the repressor element. The repressor element was shown to function in either orientation and at various distances upstream from the positive element of the TNFα promoter. The TNFα repressor site (TRS) has been localized to a 25 bp region between base pairs −254 and −230 in the promoter. This region contains a 10 bp sequence with homology to the binding site of the activator protein AP-2. Mutation of the 6 C's of this 10 bp AP-2-llke site abolish TRS repressor function. However, this AP-2-llke site is not a binding site for AP-2 protein based on gel retardation analysis. In addition, a well-characterized AP-2 binding site placed upstream of the positive element of the TNFα gene did not cause repression. Therefore, this repression is very likely mediated by a novel protein(s) which interacts with the AP-2 consensus site in the TRS.