Two Novel Ergtoxins, Blockers of K+-channels, Purified from the Mexican Scorpion Centruroides elegans elegans

  title={Two Novel Ergtoxins, Blockers of K+-channels, Purified from the Mexican Scorpion Centruroides elegans elegans},
  author={Rita Restano-Cassulini and Timoteo Olamendi‐Portugal and Fernando Z. Zamudio and Baltazar Becerril and Lourival Domingos Possani},
  journal={Neurochemical Research},
Voltage-gated potassium channels of the ether-a-go-go related gene (ERG) family are implicated in many important cellular processes. Three such genes have been cloned (erg1, erg2 and erg3) and shown to be expressed in the central nervous system (CNS) of mammalians. This communication describes the isolation and characterization of two isoforms of scorpion toxin (CeErg4 and CeErg5, systematic nomenclature γ-KTx1.7 and γ-KTx1.8, respectively) that can discriminate the various subtypes of ERG… 

Interacting sites of scorpion toxin ErgTx1 with hERG1 K+ channels.

Toxin modulators and blockers of hERG K(+) channels.

Scorpion venom components that affect ion-channels function.

Arthropod toxins acting on neuronal potassium channels

Voltage-gated potassium channels (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database

The 6TM family of K channels comprises the voltage-gated KV subfamilies, the EAG subfamily (which includes hERG channels), the Ca2+-activated Slo subfamily and the Ca1-activated SK subfamily, which possesses a pore-forming α subunit that comprise tetramers of identical subunits or of different subunits (heteromeric).

Characterization of Four Medically Important Toxins from Centruroides huichol Scorpion Venom and Its Neutralization by a Single Recombinant Antibody Fragment

The ability of scFv HV to neutralize different toxins is a significant achievement, considering the diversity of the species of Mexican venomous scorpions, so this scFV is a candidate to be part of a recombinant anti-venom against scorpion stings in Mexico.

Dissecting Toxicity: The Venom Gland Transcriptome and the Venom Proteome of the Highly Venomous Scorpion Centruroides limpidus (Karsch, 1879)

This study corroborates that, in the venom of toxic buthid scorpions, the more abundant and diverse components are ion channel-acting toxins, mainly NaScTx, while they lack the HDP diversity previously demonstrated for the non-buthid scorpions.



A toxin to nervous, cardiac, and endocrine ERG K+ channels isolated from Centruroides noxius scorpion venom

  • G. GurrolaB. Rosati E. Wanke
  • Biology
    FASEB journal : official publication of the Federation of American Societies for Experimental Biology
  • 1999
This work isolated a peptide from the scorpion Centruroides noxius Hoffmann that has no sequence homologies with other toxins, and demonstrates that it specifically inhibits (IC50 = 16±1 nM) only ERG channels of different species and distinct histogenesis.

Toxins interacting with ether-à-go-go-related gene voltage-dependent potassium channels.

Species Diversity and Peptide Toxins Blocking Selectivity of Ether-à-go-go-Related Gene Subfamily K+ Channels in the Central Nervous System

The blocking properties of specific peptide inhibitors of hERG1 channels on the human and rat isoforms are investigated and it emerged that APETx1 is exquisitely selective for ERG1 and does not compete with the other two toxins.

Novel alpha-KTx peptides from the venom of the scorpion Centruroides elegans selectively blockade Kv1.3 over IKCa1 K+ channels of T cells.

Biophysical properties of heteromultimeric erg K+ channels

Through heteromeric assembly erg channels, these subunits may contribute significantly to different physiological functions such as setting and stabilizing the resting membrane potential and modulation of action potential frequency, and result in larger current amplitudes upon both depolarization and repolarization.

APETx1, a new toxin from the sea anemone Anthopleura elegantissima, blocks voltage-gated human ether-a-go-go-related gene potassium channels.

Although they differ in their specific targets, circular dichroism spectra and molecular modeling indicate that APETx1 and BDS-I have a common molecular scaffold and belong to the same structural family of K+ channel blocking peptides.

An ERG Channel Inhibitor from the Scorpion Buthus eupeus*

The cloning, expression, and selectivity of BeKm-1 was shown to be a novel specific blocker of hERG1 potassium channels and represents a new subgroup of these toxins.

Current views on scorpion toxins specific for K+-channels.