Linked Life Data

8118044

Source:http://linkedlifedata.com/resource/pubmed/id/8118044

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1994-4-1
pubmed:abstractText
Expression of the murine erythropoietin receptor (EpoR) gene was investigated in progenitor cell lines representing distinct stages of hematopoietic differentiation. In murine erythroid cell lines, the EpoR mRNA level was fivefold higher in the more mature murine erythroleukemia (MEL) cells than in CB-5 cells and very low in granulocyte/macrophage-like FDC-P1 cells. GATA-1 mRNA was present in equivalent levels in both erythroid cell lines, but at a low level in FDC-P1 cells. To account for the elevated levels of EpoR mRNA, the activity of the promoter and expression of DNase I hypersensitive sites were assessed as markers of transcriptional activity in various cell lines. Among a series of 5' flanking restriction fragments linked to a reporter gene, a 83-bp fragment that includes binding sites for the transcription factors GATA-1 and Sp-1 gave low levels of erythroid-specific activity, and a 256-bp fragment that includes, in addition, two sites for the putative CACCC-binding protein gave the highest level of erythroid-specific transcription. DNase I footprinting showed binding of a constitutive factor to the proximal CACCC-binding site, and deletion or mutation of this site significantly reduced the overall expression while maintaining tissue-specificity. Three DNase I hypersensitive sites were detected in the 5' flanking region of the EpoR gene, two of which were unique to MEL cells. These sites were situated over the promoter region and approximately 0.5 kb and 2.4 kb upstream of the transcriptional initiation sites. A 0.8-kb restriction fragment spanning the distal site caused approximately a four-fold rise in transcription from the endogenous or a heterologous promoter in MEL cells independent of its orientation and up to 1.5-fold rise in CB-5 cells, but it was inactive in COS-1 cells that were cotransfected with an expression plasmid encoding GATA-1. These results show that (1) basal activity as well as tissue specificity of the EpoR promoter can be accounted for by its interaction with GATA-1, and (2) upstream sites regulate the strength of the promoter. Expression of the distal DNase I hypersensitive site and the corresponding enhancer activity in MEL cells suggests a role for this element in stage-specific transcriptional control.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
83
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1428-35
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:8118044-Animals, pubmed-meshheading:8118044-Base Sequence, pubmed-meshheading:8118044-Binding Sites, pubmed-meshheading:8118044-DNA-Binding Proteins, pubmed-meshheading:8118044-Deoxyribonuclease I, pubmed-meshheading:8118044-Enhancer Elements, Genetic, pubmed-meshheading:8118044-Erythroid-Specific DNA-Binding Factors, pubmed-meshheading:8118044-Erythropoiesis, pubmed-meshheading:8118044-Erythropoietin, pubmed-meshheading:8118044-GATA1 Transcription Factor, pubmed-meshheading:8118044-Gene Expression Regulation, pubmed-meshheading:8118044-Leukemia, Erythroblastic, Acute, pubmed-meshheading:8118044-Mice, pubmed-meshheading:8118044-Molecular Sequence Data, pubmed-meshheading:8118044-Nucleosomes, pubmed-meshheading:8118044-Promoter Regions, Genetic, pubmed-meshheading:8118044-RNA, Messenger, pubmed-meshheading:8118044-Restriction Mapping, pubmed-meshheading:8118044-Transcription, Genetic, pubmed-meshheading:8118044-Transcription Factors, pubmed-meshheading:8118044-Tumor Cells, Cultured
pubmed:year
1994
pubmed:articleTitle
Further characterization of cis-acting regulatory sequences in the genomic locus of the murine erythropoietin receptor: evidence for stage-specific regulation.
pubmed:affiliation
Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't