Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2002-2-25
pubmed:abstractText
Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily that acts as a key player in adipocyte differentiation, glucose metabolism, and macrophage differentiation. Osteopontin (OPN), a component of extracellular matrix, is elevated during neointimal formation in the vessel wall and is synthesized by macrophages in atherosclerotic plaques. In the present study, we investigated the molecular mechanisms regulating OPN gene expression by PPARgamma in THP-1 cells, a cell line derived from human monocytic leukemia cells. Northern and Western blot analyses showed that exposure of THP-1 cells to PMA (phorbol 12-myristate 13-acetate) increases OPN mRNA and protein levels in a time-dependent manner. PMA-induced OPN expression was significantly decreased by troglitazone (Tro) and other PPARgamma ligands. Transient transfection assays of the human OPN promoter/luciferase construct showed that PPARgamma represses OPN promoter activity, and the PPARgamma-responsive region within the OPN promoter lies between -1000 and -970 relative to the transcription start site. Site-specific mutation analysis and electrophoretic mobility shift assays indicated that a homeobox-like A/T-rich sequence between -990 and -981, which functions as a binding site for PMA-induced nuclear factors other than PPARgamma, mediates the repression of OPN expression by Tro. Furthermore, concatenated A/T-rich sequences conferred the PPARgamma responsiveness on the heterologous promoter. Taken together, these data suggest that PPARgamma ligand inhibits OPN gene expression through the interference with the binding of nuclear factors to A/T-rich sequence in THP-1 cells.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Chromans, http://linkedlifedata.com/resource/pubmed/chemical/Hypoglycemic Agents, http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Osteopontin, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Cytoplasmic and Nuclear, http://linkedlifedata.com/resource/pubmed/chemical/SPP1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Sialoglycoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate, http://linkedlifedata.com/resource/pubmed/chemical/Thiazoles, http://linkedlifedata.com/resource/pubmed/chemical/Thiazolidinediones, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/troglitazone
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1524-4571
pubmed:author
pubmed:issnType
Electronic
pubmed:day
22
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
348-55
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:11861425-AT Rich Sequence, pubmed-meshheading:11861425-Animals, pubmed-meshheading:11861425-COS Cells, pubmed-meshheading:11861425-Cell Line, pubmed-meshheading:11861425-Chromans, pubmed-meshheading:11861425-Gene Expression, pubmed-meshheading:11861425-Gene Expression Regulation, pubmed-meshheading:11861425-Genes, Reporter, pubmed-meshheading:11861425-Humans, pubmed-meshheading:11861425-Hypoglycemic Agents, pubmed-meshheading:11861425-Ligands, pubmed-meshheading:11861425-Monocytes, pubmed-meshheading:11861425-Mutagenesis, Site-Directed, pubmed-meshheading:11861425-Nuclear Proteins, pubmed-meshheading:11861425-Osteopontin, pubmed-meshheading:11861425-Promoter Regions, Genetic, pubmed-meshheading:11861425-Protein Binding, pubmed-meshheading:11861425-RNA, Messenger, pubmed-meshheading:11861425-Rabbits, pubmed-meshheading:11861425-Receptors, Cytoplasmic and Nuclear, pubmed-meshheading:11861425-Sialoglycoproteins, pubmed-meshheading:11861425-Tetradecanoylphorbol Acetate, pubmed-meshheading:11861425-Thiazoles, pubmed-meshheading:11861425-Thiazolidinediones, pubmed-meshheading:11861425-Transcription Factors, pubmed-meshheading:11861425-Transfection
pubmed:year
2002
pubmed:articleTitle
PPARgamma ligand inhibits osteopontin gene expression through interference with binding of nuclear factors to A/T-rich sequence in THP-1 cells.
pubmed:affiliation
Second Department of Internal Medicine, Gunma University School of Medicine, Maebashi, Gunma, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't