Referenced in: none

Automatically associated channels: Kv11.1

Title: New binding site on common molecular scaffold provides HERG channel specificity of scorpion toxin BeKm-1.

Authors: Yuliya V Korolkova, Eduard V Bocharov, Kamilla Angelo, Innokenty V Maslennikov, Olga V Grinenko, Aleksey V Lipkin, Elena D Nosyreva, Kirill A Pluzhnikov, Soren-Peter Olesen, Alexander S Arseniev, Eugene V Grishin

Journal, date & volume: J. Biol. Chem., 2002 Nov 8 , 277, 43104-9

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12151390

Abstract
The scorpion toxin BeKm-1 is unique among a variety of known short scorpion toxins affecting potassium channels in its selective action on ether-a-go-go-related gene (ERG)-type channels. BeKm-1 shares the common molecular scaffold with other short scorpion toxins. The toxin spatial structure resolved by NMR consists of a short alpha-helix and a triple-stranded antiparallel beta-sheet. By toxin mutagenesis study we identified the residues that are important for the binding of BeKm-1 to the human ERG K+ (HERG) channel. The most critical residues (Tyr-11, Lys-18, Arg-20, Lys-23) are located in the alpha-helix and following loop whereas the "traditional" functional site of other short scorpion toxins is formed by residues from the beta-sheet. Thus the unique location of the binding site of BeKm-1 provides its specificity toward the HERG channel.