Organization and promoter activity of the mouse syndecan-1 gene.
Syndecan-1, the prototype of a family of heparan sulfate-containing integral membrane proteoglycans, associates extracellularly with a variety of matrix molecules and growth factors and intracellularly with the actin cytoskeleton. Expressed constitutively on epithelia in mature tissues and in a developmentally regulated manner on epithelial and induced mesenchymal cells during embryogenesis, syndecan-1 appears to be involved in controlling the shape and organization of cells and tissues. To better understand the function and regulation of syndecan-1, we determined the structure of the mouse syndecan-1 gene (Synd-1). Synd-1 is approximately 19.5 kilobases in size and is organized into five exons that appear conserved in other family members. Exon 1 encodes the signal peptide; exon 2, the N-terminal glycosaminoglycan attachment region; exon 3, the bulk of the extracellular domain; exon 4, the protease-susceptible site; and exon 5, the transmembrane and cytoplasmic domains which are highly homologous between syndecan family members. Synd-1 has three transcriptional start sites, two polyadenylation sites, and is not alternatively spliced to produce its 2.6- and 3.4-kilobase mRNA species. Upstream sequences have promoter activity and contain TATA and CAAT boxes as well as a variety of other potential binding sites for transcription factors, including Sp1 (GC box), NF-kappa B, MyoD (E box), and Antennapedia. The structure of the promoter region suggests that control of Synd-1 expression is both constitutive and developmentally regulated. Because Synd-1 exons encode discrete functional domains of the syndecan-1 protein that are conserved throughout the syndecan family, all syndecan genes are likely derived from a common ancestor.
Hinkes
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Joint Program in Neonatology, Harvard Medical School, Boston, Massachusetts 02115.
Goldberger
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Neumann
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Kokenyesi
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Bernfield
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005091:Exons; D008099:Liver / Q000502:physiology*; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D011401:Promoter Regions, Genetic; D021382:Protein Sorting Signals / Q000235:genetics; D011509:Proteoglycans / Q000096:biosynthesis / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis; D015183:Restriction Mapping; D053668:Syndecan-1; D053667:Syndecans; D014162:Transfection
D008562:Membrane Glycoproteins; D009838:Oligodeoxyribonucleotides; D021382:Protein Sorting Signals; D011509:Proteoglycans; D011994:Recombinant Proteins; C508242:Sdc1 protein, mouse; D053668:Syndecan-1; D053667:Syndecans; D004247:DNA; D008156:Luciferases