Cloning of an apamin binding protein of vascular smooth muscle.
The receptor for the bee venom derived neurotoxin, apamin, is widely believed to be an integral component of the small conductance calcium-activated potassium channel in many excitable cells. By affinity chromatography on immobilized apamin, a 78 kD apamin binding protein of the bovine brain synaptosomes was isolated. Antibodies were elicited against this protein and used to clone a cDNA from a porcine vascular smooth muscle expression library. This gene (Kcal 1.8) codes for a 438 amino protein with four potential transmembrane domains, one putative calcium binding site, a protein kinase C phosphorylation site, and a leucine zipper motif. Kcal 1.8 encoded protein has no significant sequence homologies with any known ion channels or receptors. Kcal 1.8 is likely to encode a protein associated with the small conductance calcium-activated potassium channel in vascular smooth muscle.
Sokol
P T
PT
Department of Molecular Pharmacology, American Cyanamid Company, Lederle Laboratories, Pearl River, New York 10965.
Hu
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W
Yi
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Toral
J
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Chandra
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Ziai
M R
MR
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001030:Apamin / Q000378:metabolism*; D001665:Binding Sites; D015152:Blotting, Northern; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D002846:Chromatography, Affinity; D003001:Cloning, Molecular / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D015723:Gene Library; D006801:Humans; D016350:Leucine Zippers; D008545:Melanoma; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D009447:Neuroblastoma; D011061:Poly A / Q000032:analysis / Q000096:biosynthesis; D015221:Potassium Channels / Q000096:biosynthesis* / Q000737:chemistry* / Q000302:isolation & purification; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D013552:Swine; D013574:Synaptosomes / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D015221:Potassium Channels; D012333:RNA, Messenger; D011994:Recombinant Proteins; C033799:apamin receptor; D001030:Apamin; D011061:Poly A; D002118:Calcium