Reference : The enhancers of the human placental lactogen B, A, and L genes: progressive activati...
Scientific journals : Article
Life sciences : Biochemistry, biophysics & molecular biology
http://hdl.handle.net/2268/19834
The enhancers of the human placental lactogen B, A, and L genes: progressive activation during in vitro trophoblast differentiation and importance of the DF-3 element in determining their respective activities
English
Jacquemin, P. [> > > >]
Alsat, E. [> > > >]
Oury, Cécile mailto [Université de Liège - ULg > Département des sciences biomédicales et précliniques > GIGA-R : Génétique générale et humaine >]
Belayew, A. [> > > >]
Muller, Marc mailto [Université de Liège - ULg > Département des sciences de la vie > GIGA-R : Biologie et génétique moléculaire >]
Evain-Brion, D. [> > > >]
Martial, Joseph mailto [Université de Liège - ULg > Département des sciences de la vie > GIGA-R : Biologie et génétique moléculaire >]
1996
DNA & Cell Biology
Mary Ann Liebert, Inc.
15
10
845-54
Yes (verified by ORBi)
International
1044-5498
1557-7430
Larchmont
NY
[en] Base Sequence ; Cell Differentiation ; Cell Line ; Cells, Cultured ; Chloramphenicol O-Acetyltransferase/biosynthesis ; Chromosomes, Human, Pair 17 ; *Enhancer Elements, Genetic ; Female ; *Gene Expression Regulation ; Humans ; Mutagenesis ; Placenta/cytology ; Placental Lactogen/*biosynthesis/*genetics ; Polymerase Chain Reaction ; Pregnancy ; Recombinant Fusion Proteins/biosynthesis ; Sequence Homology, Nucleic Acid ; Thymidine Kinase/biosynthesis ; Transcription, Genetic ; Transfection ; Trophoblasts/cytology/*physiology
[en] The hCS-A and hCS-B genes encoding human chorionic somatomammotropin and the related hCS-L gene are very similar in their coding and flanking sequences. For each of these genes, downstream enhancers, varying in strength, have been identified with the help of cytotrophoblast-derived JEG-3 cells, which do not express the hCS genes. Here we study the activity of the hCS enhancers in human syncytiotrophoblast in primary culture, which naturally expresses the hCS genes. We show that the activity of the hCS-B gene enhancer is mediated by two elements, DF-3 and DF-4, whereas the hCS-L and hCS-A gene enhancers display weaker activity due to mutations in their respective DF-3 sites. Replacement of the hCS-B DF-3 site with the homologous hCS-A sequence causes hCS-B enhancer activity to decrease. Primary cytotrophoblasts differentiate in culture to form the syncytiotrophoblast. We show that during this process the production of hCS progressively increases and that concomitantly all three hCS enhancers are progressively activated. A targeted mutation in the 3' part of the DF-4 element abolishes the binding of a protein present only in syncytiotrophoblast extracts and inactivates the DF-4 element. Thus, a direct correlation exists between the appearance of this syncytiotrophoblast-specific protein and hCS enhancer activity. This primary culture model proves useful in studying the regulation of the hCS genes.
http://hdl.handle.net/2268/19834
1996/10/01

There is no file associated with this reference.

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.