title: Cell-type-specific expression of the platelet-derived growth factor alpha receptor: a role for GATA-binding protein.
abstract: Platelet-derived growth factor alpha receptor (PDGF alpha R) is a transmembrane tyrosine kinase receptor for all three existing PDGF isoforms, AA, AB, and BB. Transcripts of PDGF alpha R are detected as early as in fertilized mouse eggs and throughout adulthood in a time- and space-specific manner, thereby suggesting an important role of PDGFs in mammalian development. In this study, we have investigated the mechanism involved in cell-type-specific PDGF alpha R gene expression during early embryonic development. Using F9 embryonic carcinoma cells as an in vitro study model, we identified a differentiation-dependent enhancer element within the PDGF alpha R promoter that controlled receptor expression during parietal endoderm cell differentiation induced by retinoic acid and dibutyryl cyclic AMP treatment. The differentiation-dependent enhancer element sequence bore no resemblance to consensus DNA-binding sites of either the retinoic acid receptor family or the cyclic AMP-responsive element-binding protein family. It was composed of two identical 12-bp direct repeats separated by a 17-bp insert sequence enriched in C and A nucleotides. Although only a single repeat was needed to form specific DNA-protein complexes with factors present in F9 parietal endoderm cell extracts, both repeats together were necessary to display cell-type-specific enhancing activity. Mutational analysis revealed that the protein-binding sites within the repeat sequences were identical to GATA-binding sites. In this study, we provided evidence to suggest that a member of the GATA transcription factor family (GATA-4) is responsible for parietal endoderm-specific PDGF alpha R expression.
authors.affiliation: Center for Molecular Biology of Oral Diseases, College of Dentistry, University of Illinois at Chicago 60612, USA.
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: B
authors.initials: B
authors.lastname: Song
mesh_terms: D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D003994:Bucladesine / Q000494:pharmacology; D002454:Cell Differentiation; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004707:Endoderm / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D050991:GATA4 Transcription Factor; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D015336:Molecular Probe Techniques; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D020796:Receptor, Platelet-Derived Growth Factor alpha; D017479:Receptors, Platelet-Derived Growth Factor / Q000096:biosynthesis / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000378:metabolism*; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D004268:DNA-Binding Proteins; D050991:GATA4 Transcription Factor; D011994:Recombinant Proteins; D014157:Transcription Factors; D014212:Tretinoin; D003994:Bucladesine; D020796:Receptor, Platelet-Derived Growth Factor alpha; D017479:Receptors, Platelet-Derived Growth Factor