Iberiotoxin (IbTx) is a toxin that was originally isolated from Buthus tamulus scorpion venom. Iberiotoxin inhibits selectively the high conductance Ca2+-activated K+ channel (KCa1.1). This toxin does not affect other types of voltage-dependent K+ channels which are sensitive to the Charybdotoxin. Iberiotoxin is a valuable tool to study specifically Maxi-K channels.
Peptides & proteins
Galvez A, et al. (1990) Purification and characterization of a unique, potent, peptidyl probe for the high conductance calcium-activated potassium channel from venom of the scorpion Buthus tamulus. J Biol Chem.; Giangiacomo KM, et al. (1992) Mechanism of iberiotoxin block of the large-conductance calcium-activated potassium channel from bovine aortic smooth muscle. Biochemistry.; Kaczorowski GJ, et al. (1996) High-conductance calcium-activated potassium channels; structure, pharmacology, and function. J Bioenerg Biomembr.; Garcia ML, et al. (1991) Use of toxins to study potassium channels. J Bioenerg Biomembr.; Candia S., et al. (1992) Mode of action of iberiotoxin, a potent blocker of the large conductance Ca(2+)-activated K+ channel. Biophys J.