Upstream tissue inhibitor of metalloproteinases-1 (TIMP-1) element-1, a novel and essential regulatory DNA motif in the human TIMP-1 gene promoter, directly interacts with a 30-kDa nuclear protein.
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.
Trim
J E
JE
Liver Research Group, Division of Cell and Molecular Medicine, South Academic Block, Level D, Southampton General Hospital, Southampton, Hampshire SO16 6YD, United Kingdom.
Samra
S K
SK
Arthur
M J
MJ
Wright
M C
MC
McAulay
M
M
Beri
R
R
Mann
D A
DA
D000818:Animals; D002478:Cells, Cultured; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000032:analysis; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D017930:Genes, Reporter; D006801:Humans; D008099:Liver / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D051381:Rats; D017207:Rats, Sprague-Dawley; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism; D014466:Ultraviolet Rays
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D019715:Tissue Inhibitor of Metalloproteinase-1; D014157:Transcription Factors