Author(s): McAulay M; Wright MC; Mann DA; Trim JE; Samra SK; Arthur MJ; Beri R
Abstract: Elevated expression of the tissue inhibitor of metalloproteinases-1 (TIMP-1) protein and mRNA has been reported in human diseases including cancers and tissue fibrosis. Regulation of TIMP-1 gene expression is mainly mediated at the level of gene transcription and involves the activation of several well known transcription factors including those belonging to the AP-1, STAT, and Pea3/Ets families. In the current study, we have used DNase-1 footprinting to identify a new regulatory element (5'-TGTGGTTTCCG-3') present in the human TIMP-1 gene promoter. Mutagenesis and transfection studies in culture-activated rat hepatic stellate cells and the human Jurkat T cell line demonstrated that the new element named upstream TIMP-1 element-1 (UTE-1) is essential for transcriptional activity of the human TIMP-1 promoter. Electrophoretic mobility shift assay studies revealed that UTE-1 can form protein-DNA complexes of distinct mobilities with nuclear extracts from a variety of mammalian cell types and showed that induction of a high mobility UTE-1 complex is associated with culture activation of freshly isolated rat hepatic stellate cells. A combination of UV-cross-linking and Southwestern blotting techniques demonstrated that UTE-1 directly interacts with a 30-kDa nuclear protein that appears to be present in all cell types tested. We conclude that UTE-1 is a novel regulatory element that in combination with its cellular binding proteins may be an important component of the mechanisms controlling TIMP-1 expression in normal and pathological states.
Notes: 0021-9258 (Print) Journal Article
Keywords: Animals Cells, Cultured DNA Footprinting DNA-Binding Proteins/analysis Gene Expression Regulation, Enzymologic/*genetics Genes, Reporter Humans Liver/metabolism Nuclear Proteins/*metabolism *Promoter Regions (Genetics) Rats Rats, Sprague-Dawley Regulatory Sequences, Nucleic Acid/*genetics Research Support, Non-U.S. Gov't Tissue Inhibitor of Metalloproteinase-1/*genetics Transcription Factors/metabolism Ultraviolet Rays
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Professor Derek Mann
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Professor Matthew Wright
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