title: The beta-bungarotoxin-binding protein from chick brain: binding sites for different neuronal K+ channel ligands co-fractionate upon partial purification.
abstract: beta-Bungarotoxin (beta-Butx) is a presynaptically active neurotoxin which blocks neuronal A-type K+ channels. Here, the efficient solubilisation and about 300-fold purification of the beta-Butx-binding protein from chick brain were achieved by detergent extraction at high ionic strength followed by chromatography on DEAE Affigel Blue, beta-Butx Affigel 102 and wheat germ agglutinin Sepharose. Binding of 125I-labelled beta-Butx to the purified protein was inhibited by two other K+ channel ligands, dendrotoxin I and mast cell-degranulating peptide. It is concluded that the beta-Butx-binding protein is a member of a family of voltage-gated K+ channels which exhibit varying affinities for different polypeptide ligands.
authors.affiliation: ZMBH, Universität Heidelberg, Im Neuenheimer Feld, FRG.
authors.forename: R R
authors.initials: RR
authors.lastname: Schmidt
authors.forename: H
authors.initials: H
authors.lastname: Betz
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D002038:Bungarotoxins / Q000378:metabolism*; D002645:Chickens; D002846:Chromatography, Affinity; D004546:Elapid Venoms / Q000378:metabolism; D008024:Ligands; D008345:Manganese / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism; D009994:Osmolar Concentration; D010455:Peptides / Q000378:metabolism; D015221:Potassium Channels / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D012995:Solubility
chemical_list: D002038:Bungarotoxins; D004546:Elapid Venoms; D008024:Ligands; D008565:Membrane Proteins; D010455:Peptides; D015221:Potassium Channels; C008331:mast cell degranulating peptide; D008345:Manganese; C020273:dendrotoxin