Regulatory elements in the promoter region of the rat gene encoding the acyl-CoA-binding protein

• Published in: Gene 1996-09, Vol.173 (2), p.233-238
• Main Authors: Elholm, Morten, Bjerking, Gurli, Knudsen, Jens, Kristiansen, Karsten, Mandrup, Susanne
• Format: Article
• Language: English
• Subjects: Animals; AP-1; AP-2; Binding Sites; C/EBP; Carrier Proteins - genetics; Diazepam Binding Inhibitor; Electrophoresis, Polyacrylamide Gel; Gene Expression - drug effects; HNF; NF-1/CTF; peroxisome proliferator-activated receptor; peroxisome proliferators; Phosphoproteins - metabolism; Promoter Regions, Genetic; Pyrimidines - pharmacology; Rats; Rats, Sprague-Dawley; Spl; Transcription Factors - metabolism; Transfection; Tumor Cells, Cultured
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/0378-1119(96)00213-2

Acyl-CoA-binding protein (ACBP) is an ubiquitously expressed 10-kDa protein which is present in high amounts in cells involved in solute transport or secretion. Rat ACBP is encoded by a gene containing the typical hallmarks of a housekeeping gene. Analysis of the promoter region of the rat ACBP gene by electrophoretic mobility shift assay (EMSA) revealed specific binding of proteins from rat liver nuclear extracts to potential recognition sequences of NF-1/CTF, Spl, AP-1, C/EBP and HNF-3. In addition, specific binding to a DR-1 type element was observed. By using in vitro translated peroxisome proliferator activated receptors (PPAR) and a retinoid X receptor α(RXRα), we demonstrated that this DR-1 element was capable of binding PPARα/RXRα, PPARδ/RXRα and PPARγ2/RXRα heterodimers. The PPARγ2/RXRα heterodimer appeared to have the highest affinity for the ACBP DR-1 element. Addition of peroxisome proliferators (PP) to H4IIEC3 rat hepatoma cells led to an increase in the ACBP mRNA level, indicating that the DR-1 element could be a functional peroxisome proliferator responsive element (PPRE). Analysis of the ACBP promoter by transient transfection showed that deletion of the region containing the DR-1 element reduced transcriptional activity, and further indicated that three AP-2 sites and one NF-1/CTF site in the proximal promoter are of importance for basal promoter activity.