Chicken ovalbumin upstream promoter-transcription factor I represses the transcriptional activity of the human muscle glycogen phosphorylase promoter in C2C12 cells.
The responsiveness of the 1.13 kb proximal human muscle glycogen phosphorylase (MGP) gene promoter to the chicken ovalbumin upstream promoter-transcription factor (COUP-TF) repressor, known to be ablated during muscle cell differentiation, was examined. Constitutive expression of COUP-TFI repressed the activity of the promoter in C2C12 muscle cells and sequential deletion analysis mapped the sensitive region between nucleotides -362 and -185, which included a putative consensus COUP-TF binding half-site at -198/-193. Mutation of this site abolished transcriptional response to COUP-TFI of the -362 construct. A -209/-180 probe bound in vitro to COUP-TFI and to protein extracts from proliferating but not fusing myoblasts. Thus, COUP-TF may be involved in repression of the human MGP gene promoter at the myoblast stage.
Ferrer-Martínez
Andreu
A
Department de Bioquímica i Biologia Molecular, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain. aferrer@bio.ub.es
Marotta
Mario
M
Baldán
Angel
A
Haro
Diego
D
Gómez-Foix
Anna M
AM
D000818:Animals; D001665:Binding Sites; D051838:COUP Transcription Factor I; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000502:physiology*; D017353:Gene Deletion; D024981:Glycogen Phosphorylase / Q000235:genetics*; D006801:Humans; D051379:Mice; D008957:Models, Genetic; D009132:Muscles / Q000201:enzymology*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011987:Receptors, Steroid / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic
D051838:COUP Transcription Factor I; D017931:DNA Primers; D004268:DNA-Binding Proteins; C497589:NR2F1 protein, human; C497590:Nr2f1 protein, mouse; D011987:Receptors, Steroid; D014157:Transcription Factors; D024981:Glycogen Phosphorylase