SciELO - Scientific Electronic Library Online

 
vol.37 issue10A strategy for obtaining social benefits from the gene revolutionRespiration, oxidative phosphorylation, and uncoupling protein in Candida albicans author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Journal

Article

Indicators

Related links

Share


Brazilian Journal of Medical and Biological Research

Print version ISSN 0100-879XOn-line version ISSN 1414-431X

Abstract

XAVIER-NETO, J. et al. Control of the rat angiotensin I converting enzyme gene by CRE-like sequences. Braz J Med Biol Res [online]. 2004, vol.37, n.10, pp.1441-1453. ISSN 1414-431X.  https://doi.org/10.1590/S0100-879X2004001000002.

We characterized the role of potential cAMP-responsive elements (CRE) in basal and in induced angiotensin converting enzyme (ACE) gene promoter activity in order to shed light on the regulation of somatic ACE expression. We identified stimulators and repressors of basal expression between 122 and 288 bp and between 415 and 1303 bp upstream from the transcription start site, respectively, using a rabbit endothelial cell (REC) line. These regions also contained elements associated with the response to 8BrcAMP. When screening for CRE motifs we found pCRE, a proximal sequence between 209 and 222 bp. dCRE, a distal tandem of two CRE-like sequences conserved between rats, mice and humans, was detected between 834 and 846 bp. Gel retardation analysis of nuclear extracts of REC indicated that pCRE and dCRE bind to the same protein complexes as bound by a canonical CRE. Mutation of pCRE and dCRE in REC established the former as a positive element and the latter as a negative element. In 293 cells, a renal cell line, pCRE and dCRE are negative regulators. Co-transfection of ATF-2 or ATF-2 plus c-Jun repressed ACE promoter activity, suggesting that the ACE gene is controlled by cellular stress. Although mapping of cAMP responsiveness was consistent with roles for pCRE and dCRE, mutation analysis indicated that they were not required for cAMP responsiveness. We conclude that the basal activity of the somatic ACE promoter is controlled by proximal and distal CREs that can act as enhancers or repressors depending on the cell context.

Keywords : Angiotensin converting enzyme; Endothelium; cAMP; Cyclic AMP responsive element.

        · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License