Isolation of the first toxin from the scorpion Buthus occitanus israelis showing preference for Shaker potassium channels.
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.
Kozminsky-Atias
Adi
A
Department of Life Sciences and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Somech
Erez
E
Zilberberg
Noam
N
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
D012604:Scorpion Venoms; D051637:Shaker Superfamily of Potassium Channels; D004247:DNA