Cloning of a human cDNA expressing a high voltage-activating, TEA-sensitive, type-A K+ channel which maps to chromosome 1 band p21.
Over ten different mammalian genes related to the Drosophila Shaker gene (the Sh gene family) have been identified recently. These genes encode subunits of voltage-dependent K+ channels. The family consists of four subfamilies: ShI genes are homologues of Shaker; ShII, ShIII, and ShIV are homologues of three other Shaker-like genes in Drosophila, Shab, Shaw, and Shal, respectively. We report here the cloning of a human K+ channel ShIII cDNA (HKShIIIC) obtained from a brain stem cDNA library. HKShIIIC transcripts express an atypical voltage-dependent transient (A-type) K+ current in Xenopus oocytes. This current is activated by large membrane depolarizations and is extremely sensitive to the K+ channel blocker TEA unlike most A-type currents. The gene encoding HKShIIIC maps to chromosome 1p21.
Department of Physiology and Biophysics, New York University Medical Center, NY 10016.
B
B
Rudy
K
K
Sen
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Vega-Saenz de Miera
D
D
Lau
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T
Ried
D C
DC
Ward
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001933:Brain Stem / Q000502:physiology*; D002531:Cerebellum / Q000502:physiology*; D002871:Chromosome Banding; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D004330:Drosophila / Q000235:genetics; D006801:Humans; D015640:Ion Channel Gating; D007621:Karyotyping; D008564:Membrane Potentials / Q000187:drug effects; D008969:Molecular Sequence Data; D005810:Multigene Family; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D015221:Potassium Channels / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D011487:Protein Conformation; D012689:Sequence Homology, Nucleic Acid; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology*; D014158:Transcription, Genetic; D014981:Xenopus
D015221:Potassium Channels; D013757:Tetraethylammonium Compounds; D019789:Tetraethylammonium; D004247:DNA