A delayed rectifier potassium channel cloned from bovine adrenal medulla. Functional analysis after expression in Xenopus oocytes and in a neuroblastoma cell line.
Using a cDNA library from bovine adrenal medulla, and, subsequently, a bovine genomic library, we have isolated the gene coding for a non inactivating potassium channel. This gene encodes a 597-amino acid protein which we have called BAK5 as its sequence is very similar to members of Kv1.5 potassium channel family. Neuroblastoma cells (Neuro-2a cell line) were stably transfected with BAK5 DNA. Protein expression was under the control of a heat-shock promoter. Transfected cells showed a current highly selective for potassium, insensitive to tetraethylammonium but reversibly blocked by 4-aminopyridine. Oocytes injected with BAK5 mRNA also expressed a potassium current with the same characteristics.
Department of Neurochemistry, Universidad de Alicante, Spain.
M
M
García-Guzmán
F
F
Sala
M
M
Criado
S
S
Sala
D015761:4-Aminopyridine / Q000494:pharmacology; D000313:Adrenal Medulla / Q000737:chemistry*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D003001:Cloning, Molecular; D005260:Female; D015870:Gene Expression; D006801:Humans; D008969:Molecular Sequence Data; D009447:Neuroblastoma / Q000378:metabolism*; D009865:Oocytes / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D015221:Potassium Channels / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured; D014981:Xenopus
D015221:Potassium Channels; D012333:RNA, Messenger; D013757:Tetraethylammonium Compounds; D019789:Tetraethylammonium; D015761:4-Aminopyridine; D011188:Potassium