Linked Life Data

7585542

Source:http://linkedlifedata.com/resource/pubmed/id/7585542

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1995-12-6
pubmed:abstractText
Estrogen receptor (ER)-positive human breast carcinoma (HBC) cell lines express significantly higher levels of retinoic acid receptor alpha (RAR alpha) (isoform 1) mRNA than ER-negative HBCs. Estradiol enhances RAR alpha mRNA expression in different ER-positive HBCs by 2-3-fold, which in turn results in increased sensitivity of ER-positive HBCs to the growth inhibitory effects of retinoic acid. To investigate the regulatory mechanisms of estradiol-mediated enhancement of RAR alpha mRNA expression, the functional promoter for the human RAR alpha isoform 1 was cloned and used to assess estradiol-mediated promoter-dependent enhancement of firefly luciferase reporter gene activity in transiently transfected ER-positive (MCF-7 and T47D) and ER-negative (MDA-MB-231) HBCs. Deletional promoter constructs were obtained to further delineate the promoter region responsible for estradiol-mediated enhancement of promoter activity. Here, we present evidence that approximately 130 bp of the promoter fragment preceding the transcriptional start site are responsible for estradiol-mediated enhancement of hRAR alpha gene expression. The estradiol-mediated enhancement is dependent on ER binding. Further deletional analysis showed that a promoter sequence of 42 base pairs, located approximately 100 bases upstream of the transcriptional start site, contains elements for estradiol-mediated enhancement. Specific deletion of either the Sp1 motif or mutations in the imperfect half-palindromic estrogen response element motif of this fragment abolish its estradiol responsiveness in transient transfections.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4999-5006
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Estradiol regulation of the human retinoic acid receptor alpha gene in human breast carcinoma cells is mediated via an imperfect half-palindromic estrogen response element and Sp1 motifs.
pubmed:affiliation
Department of Medicine, University of Maryland School of Medicine, Baltimore, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.