title: A new Kaliotoxin selective towards Kv1.3 and Kv1.2 but not Kv1.1 channels expressed in oocytes.
abstract: In this paper were described the purification, the sequencing, and the immunological and biological characterization of a new Kaliotoxin analog, Aam-KTX, from the venom of the scorpion Androctonus amoreuxi. The toxin effects on three cloned Kv channels (Kv1.1, Kv1.2, and Kv1.3) were investigated in Xenopus oocytes using electrophysiology experiments. The Aam-KTX preference for Kv1.3 channel versus Kv1.2 was expected (EC(50) values, 1.1+/-0.02 and 10.4+/-1.5 nM, respectively) but its total inefficacy on Kv1.1 was very surprising. 3D molecular modeling of Aam-KTX brought putative answers to this difference in selectivity.
authors.affiliation: CNRS UMR 6231, CRN2M, Université de la Méditerranée et Université Paul Cézanne, 51, Bd Pierre Dramard, 13916 Marseilles, France.
authors.forename: Najwa
authors.initials: N
authors.lastname: Abbas
authors.forename: Maya
authors.initials: M
authors.lastname: Belghazi
authors.forename: Yousra
authors.initials: Y
authors.lastname: Abdel-Mottaleb
authors.forename: Jan
authors.initials: J
authors.lastname: Tytgat
authors.forename: Pierre E
authors.initials: PE
authors.lastname: Bougis
authors.forename: Marie-France
authors.initials: MF
authors.lastname: Martin-Eauclaire
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D051662:Kv1.1 Potassium Channel / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D051663:Kv1.2 Potassium Channel / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D051664:Kv1.3 Potassium Channel / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D026902:Potassium Channel Blockers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011487:Protein Conformation; D051381:Rats; D012604:Scorpion Venoms / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D012605:Scorpions / Q000737:chemistry; D014982:Xenopus laevis
chemical_list: C489293:Kcna1 protein, rat; D051663:Kv1.2 Potassium Channel; D051664:Kv1.3 Potassium Channel; D026902:Potassium Channel Blockers; D012604:Scorpion Venoms; C072276:kaliotoxin; D051662:Kv1.1 Potassium Channel