Linked Life Data

7539886

Source:http://linkedlifedata.com/resource/pubmed/id/7539886

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-7-10
pubmed:abstractText
In an effort to determine whether basic-helix-loop-helix (bHLH) proteins are important in pituitary-specific expression of the alpha-glycoprotein hormone subunit gene, we examined the effect of the dominant negative HLH protein, Id, on the activity of the alpha-subunit gene promoter in pituitary cells. Id over-expression reduces the expression of alpha-subunit reporter genes in either alpha T3-1 gonadotrope-derived or alpha TSH thyrotrope-derived cells. A deletion fragment containing nucleotides from -131 to +44 of the human alpha-subunit promoter is inhibited to a similar degree as a -244 to +44 fragment in alpha T3-1 cells. Nuclear proteins in alpha T3-1 cells bind two potential bHLH protein binding sites (E-boxes, alpha EB1 and alpha EB2) present in this fragment but not to mutations that specifically alter only these sequences. An antibody-specific for upstream stimulatory factor, a widely expressed bHLH-leucine zipper protein, is able to inhibit factor binding to the alpha EB2 sequences but not the alpha EB1 site. Mutating the alpha EB1 element of the alpha-subunit promoter decreases basal activity of this promoter to about 42% of control levels in alpha T3-1 cells. A mutation that abolishes upstream stimulatory factor binding, either alone or in combination with the alpha EB1 mutation, reduces basal activity of the promoter to approximately 21% of control levels in alpha T3-1 cells and abolishes the decrease in promoter activity seen when Id is overexpressed. These results demonstrate that the bHLH family of proteins are important regulators of alpha-subunit gene expression in pituitary cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
278-91
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:7539886-Animals, pubmed-meshheading:7539886-Base Sequence, pubmed-meshheading:7539886-Binding Sites, pubmed-meshheading:7539886-Cell Nucleus, pubmed-meshheading:7539886-Cells, Cultured, pubmed-meshheading:7539886-DNA, pubmed-meshheading:7539886-DNA-Binding Proteins, pubmed-meshheading:7539886-Gene Expression Regulation, pubmed-meshheading:7539886-Glycoprotein Hormones, alpha Subunit, pubmed-meshheading:7539886-Helix-Loop-Helix Motifs, pubmed-meshheading:7539886-Humans, pubmed-meshheading:7539886-Inhibitor of Differentiation Protein 1, pubmed-meshheading:7539886-Mice, pubmed-meshheading:7539886-Molecular Sequence Data, pubmed-meshheading:7539886-Pituitary Gland, pubmed-meshheading:7539886-Promoter Regions, Genetic, pubmed-meshheading:7539886-Repressor Proteins, pubmed-meshheading:7539886-Transcription Factors, pubmed-meshheading:7539886-Upstream Stimulatory Factors
pubmed:year
1995
pubmed:articleTitle
Upstream stimulatory factor, a basic-helix-loop-helix-zipper protein, regulates the activity of the alpha-glycoprotein hormone subunit gene in pituitary cells.
pubmed:affiliation
Department of Medicine, University of Colorado Health Science Center, Denver 80262, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't