Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1993-11-24
pubmed:abstractText
The reversible interaction of the retinoblastoma susceptibility gene product (Rb) with the cellular transcription factor E2F has recently been demonstrated. Activation of the adenovirus E2a promoter by the products of the viral E1a gene correlates with the ability of both early E1a proteins to sequester Rb, thereby releasing E2F from inactive complexes with this protein. The E2a promoter is also efficiently stimulated by a product (17.5 kDa) of the viral E4 gene. The specific interaction of this E4 protein with E2F results in the formation of complexes that bind cooperatively to the two neighboring E2F binding sites in the E2a promoter. We have previously shown that in undifferentiated F9 cells (F9EC) the E2a promoter is refractory to E2F-mediated activation by E1a, but not by E4. Using both band-shift and transfection experiments, we now demonstrate (i) that in F9EC cells the E4 product, in combination with E2F, recruits Rb into a stable multiprotein complex and (ii) that in these undifferentiated cells, as opposed to their differentiated counterpart, Rb is actively involved in the transcriptional stimulation of the E2a promoter by E4. Our results suggest that, depending on the cell state, Rb may behave either as a transcriptional activator (F9EC cells) or as a transcriptional inhibitor (differentiated F9 cells).
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Adenovirus E2 Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Arid4a protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Cell Cycle Proteins, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/E2F Transcription Factors, http://linkedlifedata.com/resource/pubmed/chemical/Retinoblastoma Protein, http://linkedlifedata.com/resource/pubmed/chemical/Retinoblastoma-Binding Protein 1, http://linkedlifedata.com/resource/pubmed/chemical/Trans-Activators, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factor DP1, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factors
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0950-9232
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2977-86
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:8414500-Adenovirus E2 Proteins, pubmed-meshheading:8414500-Amino Acid Sequence, pubmed-meshheading:8414500-Animals, pubmed-meshheading:8414500-Antibody Specificity, pubmed-meshheading:8414500-Base Sequence, pubmed-meshheading:8414500-Carrier Proteins, pubmed-meshheading:8414500-Cell Cycle Proteins, pubmed-meshheading:8414500-Cell Line, pubmed-meshheading:8414500-DNA-Binding Proteins, pubmed-meshheading:8414500-E2F Transcription Factors, pubmed-meshheading:8414500-Mice, pubmed-meshheading:8414500-Molecular Sequence Data, pubmed-meshheading:8414500-Phosphorylation, pubmed-meshheading:8414500-Promoter Regions, Genetic, pubmed-meshheading:8414500-Retinoblastoma Protein, pubmed-meshheading:8414500-Retinoblastoma-Binding Protein 1, pubmed-meshheading:8414500-Trans-Activators, pubmed-meshheading:8414500-Transcription Factor DP1, pubmed-meshheading:8414500-Transcription Factors
pubmed:year
1993
pubmed:articleTitle
Rb may act as a transcriptional co-activator in undifferentiated F9 cells.
pubmed:affiliation
Laboratoire de Génétique Moléculaire des Eucaryotes (CNRS), Unité 184 (INSERM), Strasbourg, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't