title: Genomic structure and promoter sequence of the insulin-dependent diabetes mellitus autoantigen, IA-2 (PTPRN).
abstract: IA-2 is a transmembrane protein tyrosine phosphatase, expressed in neuroendocrine cells, and a major autoantigen in insulin-dependent diabetes mellitus. In the present study we elucidated the structure of the IA-2 gene (HGMW-approved symbol PTPRN) and its promoter sequence. A 40-kb genomic clone covering the whole IA-2 coding sequence and 4 kb proximal 5'-upstream sequence was isolated and mapped. The IA-2 gene encompasses approximately 20 kb with 23 exons ranging from 34 bp to more than 650 bp. The extracellular domain is encoded by exons 1-12, the transmembrane region by exon 13, and the intracellular domain by exons 14-23. The transcriptional start site(s) of the IA-2 gene was mapped by 5' rapid amplification of cDNA ends to 97 bp upstream of the translational start site. A 3-kb 5'-upstream region was sequenced, revealing a GC-rich region and TATA-less sequence containing several potential transcription-regulating sites (i.e., Sp1, CREB, GATA-1, and MZF). Functional promoter activity was confirmed by transient transfection of U87MG cells with deletion mutants linked to a luciferase reporter gene.
authors.affiliation: Experimental Medicine Section, Oral Infection and Immunity Branch, Bethesda, Maryland, 20892-4322, USA.
authors.forename: J
authors.initials: J
authors.lastname: Xie
authors.forename: B
authors.initials: B
authors.lastname: Zhang
authors.forename: M S
authors.initials: MS
authors.lastname: Lan
authors.forename: A L
authors.initials: AL
authors.lastname: Notkins
mesh_terms: D001323:Autoantibodies / Q000235:genetics* / Q000276:immunology; D001324:Autoantigens; D001483:Base Sequence; D003001:Cloning, Molecular; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D005091:Exons / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D005968:Glutamate Decarboxylase / Q000235:genetics / Q000276:immunology; D006801:Humans; D007438:Introns / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics*; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion / Q000235:genetics; D014162:Transfection / Q000235:genetics; D014407:Tumor Cells, Cultured
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; C096322:ICA512 autoantibody; D008565:Membrane Proteins; C516862:PTPRN protein, human; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D017027:Protein Tyrosine Phosphatases; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8; D005968:Glutamate Decarboxylase