title: Induction of murine adenosine A(2A) receptor expression by LPS: analysis of the 5' upstream promoter.
abstract: Non-activated macrophages express low levels of A(2A)Rs and lipopolysaccharides (LPS) upregulates A(2A)R expression in an NF-κB-dependent manner. The murine A(2A)R gene is encoded by three exons, m1, m2 and m3. Exons m2 and m3 are conserved, while m1 encodes the 5' untranslated UTR. Three m1 variants have been defined, m1A, m1B and m1C, with m1C being farthest from the transcriptional start site. LPS upregulates A(2A)Rs in primary murine peritoneal and bone-marrow-derived macrophages and RAW264.7 cells by selectively splicing m1C to m2, through a promoter located upstream of m1C. We have cloned ∼1.6 kb upstream of m1C into pGL4.16(luc2CP/Hygro) promoterless vector. This construct in RAW 264.7 cells responds to LPS, and adenosine receptor agonists augmented LPS responsiveness. The NF-κB inhibitors BAY-11 and triptolide inhibited LPS-dependent induction. Deletion of a key proximal NF-κB site (402-417) abrogated LPS responsiveness, while deletion of distal NF-κB and C/EBPβ sites did not. Site-directed mutagenesis of CREB (309-320), STAT1 (526-531) and AP2 (566-569) sites had little effect on LPS and adenosine receptor agonist responsiveness; however, mutation of a second STAT1 site (582-588) abrogated this responsiveness. Further analysis of this promoter should provide valuable insights into regulation of A(2A)R expression in macrophages in response to inflammatory stimuli.
authors: Department of Cell Biology and Molecular Medicine and The Cardiovascular Research Institute, Newark, NJ, USA.
authors: G
authors: G
authors: Elson
authors: M
authors: M
authors: Eisenberg
authors: C
authors: C
authors: Garg
authors: S
authors: S
authors: Outram
authors: C J
authors: CJ
authors: Ferrante
authors: G
authors: G
authors: Hasko
authors: S J
authors: SJ
authors: Leibovich
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D002478:Cells, Cultured; D004224:Diterpenes / Q000494:pharmacology; D004852:Epoxy Compounds / Q000494:pharmacology; D005091:Exons / Q000235:genetics; D005260:Female; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D010616:Phenanthrenes / Q000494:pharmacology; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020033:Protein Isoforms / Q000235:genetics; D058906:Purinergic P1 Receptor Agonists / Q000494:pharmacology; D043705:Receptor, Adenosine A2A / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050794:STAT1 Transcription Factor / Q000378:metabolism; D013450:Sulfones / Q000494:pharmacology; D015533:Transcriptional Activation / Q000187:drug effects*
chemical_list: C434003:3-(4-methylphenylsulfonyl)-2-propenenitrile; D004224:Diterpenes; D004852:Epoxy Compounds; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009570:Nitriles; D010616:Phenanthrenes; D020033:Protein Isoforms; D058906:Purinergic P1 Receptor Agonists; D043705:Receptor, Adenosine A2A; D050794:STAT1 Transcription Factor; D013450:Sulfones; C001899:triptolide; D008156:Luciferases