Genomic structure and promoter analysis of the rat kir7.1 potassium channel gene (Kcnj13).
In the brain inwardly rectifying potassium channel Kir7.1 subunits are predominantly expressed in the choroid plexus and meninges. To investigate this tissue-specific expression pattern, we characterized the genomic organization and the 5' proximal promoter of the rat Kir7.1 gene (Kcnj13). Starting from the major transcriptional initiation site, three exons in Kcnj13 give rise to the dominant approximately 1.45 kb transcript in brain. Adjacent to the transcriptional start the minimal promoter which, uncommon for ion channels, contains a TATA- and CAAT-box is controlled by AP-1 factors and accounts for high gene expression levels. Luciferase reporter gene responses driven by the first 2.1 kb of the 5' flanking region were similarly high in epithelial FRTL-5 and neuronal N2A cells, suggesting that neuron-specific repressor elements are located remote from the non-selective minimal promoter.
Döring
F
F
Molecular Neurobiology of Signal Transduction, Max-Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37070 Göttingen, Germany. fdoerin@gwdg.de
Karschin
A
A
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D004247:DNA / Q000737:chemistry / Q000235:genetics; D005091:Exons; D005796:Genes / Q000235:genetics*; D006801:Humans; D007438:Introns; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D015221:Potassium Channels / Q000235:genetics* / Q000378:metabolism; D024661:Potassium Channels, Inwardly Rectifying; D011401:Promoter Regions, Genetic / Q000235:genetics*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D011993:Recombinant Fusion Proteins; D004247:DNA; D008156:Luciferases