Linked Life Data

12391281

Source:http://linkedlifedata.com/resource/pubmed/id/12391281

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2002-10-22
pubmed:abstractText
In previous studies, we reported that the level of expression of the adenylyl cyclase inhibitory A3 adenosine receptor (AR) impacts vascular tone and that rat vascular smooth muscle cells (VSMCs) coexpress the A3 AR and the adenylyl cyclase stimulatory A2a- and A2b-type ARs. In the current study, we investigated the regulation of expression of the A3 AR gene, focusing on sequences conserved in the mouse and human promoters. Transient transfection of primary cultures of rat VSMCs, using the mouse A3 AR promoter, shows that mutation of a conserved cAMP response element (CRE) significantly up-regulates promoter activity in first passage cells, whereas mutation of a conserved GATA site reduces promoter activity. This suggests that an inhibitory protein binds the CRE, whereas an enhancing factor binds the GATA sequence. Electrophoretic mobility shift assays (EMSAs) indicate that the putative CRE and GATA sites indeed bind cAMP response element modulator 1/c-Jun and the GATA6 protein, respectively. A3 AR promoter activity is significantly up-regulated in the presence of forskolin, the nonselective agonist 5'-(N-ethylcarboxamido)adenosine, or the A2a AR agonist 4-[2-[[6-amino-9(N-ethyl-beta-D-ribofuranuronamidosyl)-9H-purin-2-yl]amino]ethyl]benzenepro- panoic acid (CGS21680), reaching levels similar to those of the A3 AR promoter bearing a mutated CRE. EMSA indicates that in the presence of forskolin the binding to the CRE is inhibited, suggesting that cAMP elevation disturbs the formation of an inhibitory complex on the CRE. Finally, semiquantitative reverse transcription-polymerase chain reaction analysis reveals that endogenous A3 AR mRNA is elevated in response to forskolin. Our findings suggest the presence of a mechanism by which cAMP might control its own level in cells via regulation of genes involved in modulation of adenylyl cyclase activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1167-76
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:12391281-Adenylate Cyclase, pubmed-meshheading:12391281-Animals, pubmed-meshheading:12391281-Cyclic AMP, pubmed-meshheading:12391281-Cyclic AMP Response Element-Binding Protein, pubmed-meshheading:12391281-DNA-Binding Proteins, pubmed-meshheading:12391281-Enzyme Activation, pubmed-meshheading:12391281-Forskolin, pubmed-meshheading:12391281-GATA6 Transcription Factor, pubmed-meshheading:12391281-Gene Expression Regulation, pubmed-meshheading:12391281-Mast Cells, pubmed-meshheading:12391281-Mice, pubmed-meshheading:12391281-Muscle, Smooth, Vascular, pubmed-meshheading:12391281-Promoter Regions, Genetic, pubmed-meshheading:12391281-Protein Binding, pubmed-meshheading:12391281-RNA, Messenger, pubmed-meshheading:12391281-Rats, pubmed-meshheading:12391281-Receptor, Adenosine A3, pubmed-meshheading:12391281-Receptors, Purinergic P1, pubmed-meshheading:12391281-Transcription Factors
pubmed:year
2002
pubmed:articleTitle
Regulation of the A3 adenosine receptor gene in vascular smooth muscle cells: role of a cAMP and GATA element.
pubmed:affiliation
Department of Biochemistry and Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.