Linked Life Data

15716114

Source:http://linkedlifedata.com/resource/pubmed/id/15716114

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-4-12
pubmed:abstractText
Although ambient levels of estradiol and synthesis of the osteoblast growth factor IGF-I are inversely related in vivo, estradiol has little or no direct effect on igf1 gene expression in rat osteoblasts in vitro. Rather, estradiol suppresses the effect of hormones that enhance igf1 expression through protein kinase A dependent activation of CCAAT enhancer binding protein (C/EBP) transcription factors. We show here that inhibition of C/EBP activity by estradiol relates to the level of estrogen receptor alpha (ERalpha) expression, and that a complex between hormone-activated ERalpha and C/EBPdelta inhibits transcription by each factor. Protein fragmentation, co-immunoprecipitation, and gene expression studies identified domains for physical and functional interactions between ERalpha and C/EBPdelta. Whereas ERalpha and fragments comprising its various domains associated with C/EBPdelta, only ERalpha fragment A/B alone replicated the suppressive effect of intact ERalpha on endogenous C/EBPdelta activity. Complementary studies showed that several carboxyl regions of C/EBPdelta cooperatively inhibit ERalpha dependent transcription. Therefore, multiple domains of C/EBPdelta and ERalpha can physically interact to alter gene expression in osteoblasts in selective ways that depend on variations in the local hormone environment. Their combined effects on one important gene target, igf1, may help to determine the balance in the overall rates of bone formation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0378-1119
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
345
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
225-35
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Interactions between CCAAT enhancer binding protein delta and estrogen receptor alpha control insulin-like growth factor I (igf1) and estrogen receptor-dependent gene expression in osteoblasts.
pubmed:affiliation
Department of Surgery, Yale University School of Medicine, New Haven, CT 06520-8041, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't