Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-13
pubmed:abstractText
Previous studies have shown that both the signal transducer and activator of transcription 5 (STAT5) and the CCAAT enhancer binding proteins (C/EBPs) are involved in the regulation of casein gene expression by mammary epithelial cells. Prolactin (Prl) activation of STAT5 is necessary for casein gene expression. The extracellular matrix (ECM) regulates also casein gene expression. Here, we have investigated whether ECM regulates C/EBPs activity in primary rabbit mammary epithelial cells. Isolated primary mammary cells were cultured on plastic or on floating collagen I gel. Prolactin induced alphas 1-casein gene expression when cells were cultured on collagen but not on plastic. It is noteworthy that activated STAT5 was detected in both culture conditions. Several STAT5 isoforms (STAT5a, STAT5b, and other STAT5 related isoforms, some with lower molecular weight than the full-length STAT5a and STAT5b) were detected under the different culture conditions. However, their presence was not related to the expression of alphas 1-casein gene. The binding of nuclear factors to a C/EBP specific binding site and the protein level of C/EBPbeta differed in cells cultured on plastic or on collagen but these parameters were not modified by Prl. This suggests that C/EBP binding activity was regulated by ECM and not by Prl. Interestingly, these modifications were correlated to the expression of the alphas 1-casein gene. Hence, the activation of the alphas 1-casein gene expression depends on two independent signals, one delivered by Prl via the activation of STAT5, the other delivered by ECM via C/EBP.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/CCAAT-Enhancer-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Caseins, http://linkedlifedata.com/resource/pubmed/chemical/Collagen, http://linkedlifedata.com/resource/pubmed/chemical/DNA, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Milk Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Plastics, http://linkedlifedata.com/resource/pubmed/chemical/Prolactin, http://linkedlifedata.com/resource/pubmed/chemical/Protein Isoforms, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/STAT5 Transcription Factor, http://linkedlifedata.com/resource/pubmed/chemical/Trans-Activators
pubmed:status
MEDLINE
pubmed:issn
0730-2312
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
371-86
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:11500914-Animals, pubmed-meshheading:11500914-Apoptosis, pubmed-meshheading:11500914-Breast, pubmed-meshheading:11500914-CCAAT-Enhancer-Binding Proteins, pubmed-meshheading:11500914-Caseins, pubmed-meshheading:11500914-Cell Culture Techniques, pubmed-meshheading:11500914-Cells, Cultured, pubmed-meshheading:11500914-Collagen, pubmed-meshheading:11500914-Cytosol, pubmed-meshheading:11500914-DNA, pubmed-meshheading:11500914-DNA-Binding Proteins, pubmed-meshheading:11500914-Extracellular Matrix, pubmed-meshheading:11500914-Female, pubmed-meshheading:11500914-Gene Expression Regulation, pubmed-meshheading:11500914-Milk Proteins, pubmed-meshheading:11500914-Plastics, pubmed-meshheading:11500914-Prolactin, pubmed-meshheading:11500914-Protein Binding, pubmed-meshheading:11500914-Protein Isoforms, pubmed-meshheading:11500914-RNA, Messenger, pubmed-meshheading:11500914-Rabbits, pubmed-meshheading:11500914-Response Elements, pubmed-meshheading:11500914-STAT5 Transcription Factor, pubmed-meshheading:11500914-Trans-Activators
pubmed:year
2001
pubmed:articleTitle
Extracellular matrix regulates alpha s1-casein gene expression in rabbit primary mammary cells and CCAAT enhancer binding protein (C/EBP) binding activity.
pubmed:affiliation
Biologie du Développement et Biotechnologies, Institut National de la Recherche Agronomique, 78352 Jouy en Josas, France. gjolivet@biotec.jouy.inra.fr
pubmed:publicationType
Journal Article, Comparative Study