Overview
- Crest, M. et al. (1992) J. Biol. Chem. 267, 1640.
- Romi, R. et al. (1993) J. Biol. Chem. 268, 26302.
- Mourre, C. et al. (1999) J. Pharmcol. Exp. Ther. 291, 943.
Alomone Labs Kaliotoxin-1 blocks KV1.3 channels expressed in Xenopus oocytes.A. Representative time course of Kaliotoxin-1 (#STK-370) inhibition of normalized KV1.3 current. Membrane potential was held at -80 mV, current was elicited by a 100 ms voltage ramp to +40 mV every 10 sec, and significantly inhibited by 0.5 nM (green) Kaliotoxin-1.
B. Superimposed traces of KV1.3 channel currents in the absence (control) and presence of 0.5 nM (green) Kaliotoxin-1 (taken from the recording in A).
Kaliotoxin-1 is a 38 amino acid long toxin, originally isolated from the venom of Androctonus mauretanicus mauretanicus scorpion and is classified as α-KTX 3.1 scorpion toxin family, having three disulfide bridges1,2.
Kaliotoxin-1 is a potent inhibitor of large conductance Ca2+-activated K+ channels (BKCa)3, and it also binds and inhibits Dendrotoxin-sensitive voltage-dependent K+ channels, mainly KV1.1 (KCNA1), KV1.2 (KCNA2) and KV1.3 (KCNA3) with a Kd of 1.5, 25 and 0.1 nM, respectively4-6. Its binding affinity to rat brain synaptosomes is 5-fold higher than that of Kaliotoxin-37.
The 3D structure of Kaliotoxin was determined by NMR spectroscopy and showed significant differences from structures established for other related scorpion toxins8,9.
In vivo application of Kaliotoxin was shown to facilitate cognitive processes such as learning in rats10.
