Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2000-2-3
pubmed:databankReference
pubmed:abstractText
To elucidate the molecular mechanisms involved in the delayed induction of PGHS-2 in species with a long ovulatory process, a 1. 6-kilobase fragment of the bovine PGHS-2 promoter was isolated, and its activity was characterized in primary cultures of bovine granulosa cells. Promoter activity assays performed with a series of deletion mutants revealed that the promoter region from -149 to -2 (+1 = transcription start site) confers full-length promoter activity in response to forskolin (10 microM). Four consensus cis-elements were identified within this region, including an E-box, ATF/CRE, C/EBP, and AP2 site. Site-directed mutagenesis showed that the E-box was required for PGHS-2 promoter activity, that disruption of the C/EBP element decreased forskolin inducible activity by 29%, whereas point mutation within the ATF/CRE and AP2 element had no inhibitory effect. Electrophoretic mobility shift assays (EMSAs) performed with the -149/-2 fragment and granulosa cell nuclear extracts obtained before (0 h) and after (18 and 20 h) human chorionic gonadotropin (hCG) revealed the regulation of multiple DNA-protein complexes. The 0-h extract generated four complexes at the E-box, whereas only one complex was produced at this site with the 18-h extract. Supershift EMSAs identified that upstream stimulatory factor-1 and -2 (USF-1 and -2) were part of these complexes. Interestingly, the presence of the amino-terminal truncated USF-2, which lacks the transcription activation domain, was detected in the 0-h extract, but not in extracts prepared post-hCG. Supershift EMSAs also indicated high levels of C/EBPbeta binding to its cis-element in the 0-h extract, which contrasts with results previously reported in rats. Thus, high levels of amino-terminal truncated USF-2 and C/EBPbeta in bovine granulosa cells prior to hCG treatment could repress gene expression, and be involved in the delayed induction of PGHS-2 in species with a long ovulatory process.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35037-45
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:10574982-Amino Acid Sequence, pubmed-meshheading:10574982-Animals, pubmed-meshheading:10574982-Base Sequence, pubmed-meshheading:10574982-Cattle, pubmed-meshheading:10574982-Cells, Cultured, pubmed-meshheading:10574982-Cyclooxygenase 2, pubmed-meshheading:10574982-DNA-Binding Proteins, pubmed-meshheading:10574982-Down-Regulation, pubmed-meshheading:10574982-Female, pubmed-meshheading:10574982-Forskolin, pubmed-meshheading:10574982-Gonadotropins, pubmed-meshheading:10574982-Granulosa Cells, pubmed-meshheading:10574982-Immunoblotting, pubmed-meshheading:10574982-Isoenzymes, pubmed-meshheading:10574982-Molecular Sequence Data, pubmed-meshheading:10574982-Mutagenesis, Site-Directed, pubmed-meshheading:10574982-Oligonucleotides, pubmed-meshheading:10574982-Promoter Regions, Genetic, pubmed-meshheading:10574982-Prostaglandin-Endoperoxide Synthases, pubmed-meshheading:10574982-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:10574982-Sequence Homology, Nucleic Acid, pubmed-meshheading:10574982-Time Factors, pubmed-meshheading:10574982-Transcription Factors, pubmed-meshheading:10574982-Upstream Stimulatory Factors
pubmed:year
1999
pubmed:articleTitle
The delayed activation of the prostaglandin G/H synthase-2 promoter in bovine granulosa cells is associated with down-regulation of truncated upstream stimulatory factor-2.
pubmed:affiliation
Centre de Recherche en Reproduction Animale, Faculté de Médecine Vétérinaire, Université de Montréal, C.P. 5000, Saint-Hyacinthe, Québec J2S 7C6, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't