Use of toxins to study potassium channels
- PMID:1917911
- DOI: 10.1007/BF00785814
Use of toxins to study potassium channels
Abstract
Potassium channels comprise groups of diverse proteins which can be distinguished according to each member's biophysical properties. Some types of K+ channels are blocked with high affinity by specific peptidyl toxins. Three toxins, charybdotoxin, iberiotoxin, and noxiustoxin, which display a high degree of homology in their primary amino acid sequences, have been purified to homogeneity from scorpion venom. While charybdotoxin and noxiustoxin are known to inhibit more than one class of channel (i.e., several Ca(2+)-activated and voltage-dependent K+ channels), iberiotoxin appears to be a selective blocker of the high-conductance, Ca(2+)-activated K+ channel that is present in muscle and neuroendocrine tissue. A distinct class of small-conductance Ca(2+)-activated K+ channel is blocked by two other toxins, apamin and leiurotoxin-1, that share no sequence homology with each other. A family of homologous toxins, the dendrotoxins, have been purified from venom of various related species of snakes. These toxins inhibit several inactivating voltage-dependent K+ channels. Although molecular biology approaches have been employed to identify and characterize several species of voltage-gated K+ channels, toxins directed against a particular channel can still be useful in defining the physiological role of that channel in a particular tissue. In addition, for those K+ channels which are not yet successfully probed by molecular biology techniques, toxins can be used as biochemical tools with which to purify the target protein of interest.
Similar articles
- Tityustoxin K alpha blocks voltage-gated noninactivating K+ channels and unblocks inactivating K+ channels blocked by alpha-dendrotoxin in synaptosomes.Rogowski RS, Krueger BK, Collins JH, Blaustein MP.Rogowski RS, et al.Proc Natl Acad Sci U S A. 1994 Feb 15;91(4):1475-9. doi: 10.1073/pnas.91.4.1475.Proc Natl Acad Sci U S A. 1994.PMID:7509073Free PMC article.
- An emerging pharmacology of peptide toxins targeted against potassium channels.Moczydlowski E, Lucchesi K, Ravindran A.Moczydlowski E, et al.J Membr Biol. 1988 Oct;105(2):95-111. doi: 10.1007/BF02009164.J Membr Biol. 1988.PMID:2464066Review.
- Polypeptide toxins from the venoms of Old World and New World scorpions preferentially block different potassium channels.Blaustein MP, Rogowski RS, Schneider MJ, Krueger BK.Blaustein MP, et al.Mol Pharmacol. 1991 Dec;40(6):932-42.Mol Pharmacol. 1991.PMID:1758443
- Characterization of the outer pore region of the apamin-sensitive Ca2+-activated K+ channel rSK2.Jäger H, Grissmer S.Jäger H, et al.Toxicon. 2004 Jun 15;43(8):951-60. doi: 10.1016/j.toxicon.2004.03.025.Toxicon. 2004.PMID:15208028
- Charybdotoxin and its effects on potassium channels.Garcia ML, Knaus HG, Munujos P, Slaughter RS, Kaczorowski GJ.Garcia ML, et al.Am J Physiol. 1995 Jul;269(1 Pt 1):C1-10. doi: 10.1152/ajpcell.1995.269.1.C1.Am J Physiol. 1995.PMID:7543240Review.
Cited by
- Mitochondrial small conductance SK2 channels prevent glutamate-induced oxytosis and mitochondrial dysfunction.Dolga AM, Netter MF, Perocchi F, Doti N, Meissner L, Tobaben S, Grohm J, Zischka H, Plesnila N, Decher N, Culmsee C.Dolga AM, et al.J Biol Chem. 2013 Apr 12;288(15):10792-804. doi: 10.1074/jbc.M113.453522. Epub 2013 Feb 19.J Biol Chem. 2013.PMID:23430260Free PMC article.
- Hydrogen peroxide inhibits cytochrome p450 epoxygenases: interaction between two endothelium-derived hyperpolarizing factors.Larsen BT, Gutterman DD, Sato A, Toyama K, Campbell WB, Zeldin DC, Manthati VL, Falck JR, Miura H.Larsen BT, et al.Circ Res. 2008 Jan 4;102(1):59-67. doi: 10.1161/CIRCRESAHA.107.159129. Epub 2007 Nov 1.Circ Res. 2008.PMID:17975109Free PMC article.
- Voltage-dependent potassium currents expressed in Xenopus laevis oocytes after injection of mRNA isolated from trophozoites of Giardia lamblia (strain Portland-1).Ponce A, Jimenez-Cardoso E, Eligio-Garcia L.Ponce A, et al.Physiol Rep. 2013 Dec 29;1(7):e00186. doi: 10.1002/phy2.186. eCollection 2013 Dec 1.Physiol Rep. 2013.PMID:24744864Free PMC article.
- Selective block by alpha-dendrotoxin of the K+ inward rectifier at the Vicia guard cell plasma membrane.Obermeyer G, Armstrong F, Blatt MR.Obermeyer G, et al.J Membr Biol. 1994 Feb;137(3):249-59. doi: 10.1007/BF00232593.J Membr Biol. 1994.PMID:8182733
- A role for BK channels in heart rate regulation in rodents.Imlach WL, Finch SC, Miller JH, Meredith AL, Dalziel JE.Imlach WL, et al.PLoS One. 2010 Jan 14;5(1):e8698. doi: 10.1371/journal.pone.0008698.PLoS One. 2010.PMID:20090847Free PMC article.
References
Publication types
MeSH terms
Substances
LinkOut - more resources
Miscellaneous