title: Isolation of the first toxin from the scorpion Buthus occitanus israelis showing preference for Shaker potassium channels.
abstract: We have purified BoiTx1, the first toxin from the venom of the Israeli scorpion, Buthus occitanus israelis, and studied its activity and genomic organization. BoiTx1 is a 37 amino acid-long peptide contained six conserved cysteines, and is classified as an alpha-KTx3.10 toxin. The pharmacological effects of BoiTx1 were studied on various cloned K(+) channels expressed in Xenopus laevis oocytes. BoiTx1 inhibited currents through Drosophila Shaker channels with an IC(50) value of 3.5+/-0.5nM, yet had much lesser effect on its mammalian orthologs. Thus, BoiTx1 is the first member of the alpha-KTx3 family that preferentially affects insect potassium channels.
authors.affiliation: Department of Life Sciences and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Kozminsky-Atias
authors.forename: Erez
authors.initials: E
authors.lastname: Somech
authors.forename: Noam
authors.initials: N
authors.lastname: Zilberberg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004594:Electrophysiology; D008969:Molecular Sequence Data; D012604:Scorpion Venoms / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D012605:Scorpions / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D051637:Shaker Superfamily of Potassium Channels / Q000187:drug effects / Q000502:physiology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D012604:Scorpion Venoms; D051637:Shaker Superfamily of Potassium Channels; D004247:DNA