Exploring structural features of the interaction between the scorpion toxinCnErg1 and ERG K+ channels

  title={Exploring structural features of the interaction between the scorpion toxinCnErg1 and ERG K+ channels},
  author={Karine Fr{\'e}nal and Chenqi Xu and Nicolas Wolff and Karine Wecker and Georgina B. Gurrola and Shun Zhu and Cheng-wu Chi and Lourival Domingos Possani and Jan Tytgat and Muriel Delepierre},
  journal={Proteins: Structure},
The γ‐KTx–type scorpion toxins specific for K+ channels were found to interact with ERG channels on the turret region, while α‐KTx3.2 Agitoxin‐2 binds to the pore region of the Shaker K+ channel, and α‐KTx5.3 BmP05 binds to the intermediate region of the small‐conductance calcium‐activated K‐channel (SKCa). In order to explore the critical residues for γ‐KTx binding, we determined the NMR structure of native γ‐KTx1.1 (CnErg1), a 42 amino acid residues scorpion toxin isolated from the venom of… 

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

Characterization of Kbot21 Reveals Novel Side Chain Interactions of Scorpion Toxins Inhibiting Voltage-Gated Potassium Channels

A new short polypeptide called Kbot21 has been purified to homogeneity from the venom of Buthus occitanus tunetanus scorpion, structurally related to BmBKTx1 from the Venom of the Asian scorpion Buthus martensii Karsch.

Solution structure of APETx1 from the sea anemone Anthopleura elegantissima: A new fold for an HERG toxin

The structure of APETx1 is compared to those of the two other known effectors of the Ether‐a‐gogo potassium channel, CnErg1 and BeKm‐1, and the topological disposition of key functional residues proposed by analysis of the electrostatic anisotropy is analyzed.

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

The receptor site of the spider toxin PcTx1 on the proton‐gated cation channel ASIC1a

Results obtained from chimeras indicate that PcTx1 does not bind to ASIC1a transmembrane domains, involved in formation of the ion pore, but binds principally on both cysteine‐rich domains I and II of the extracellular loop.

Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel

This work describes the purification and electrophysiological characterization of a Centruroides margaritatus venom component acting on hERG1 channels, the CmERG1 toxin, and suggests a more stable plug of the hERG channel, compared to that formed by other ɣ-KTx.

Beyond hemostasis: a snake venom serine protease with potassium channel blocking and potential antitumor activities

This work reports the hitherto unknown inhibitory effect of a SVSP, named collinein-1, isolated from the venom of Crotalus durissus collilineatus, on a cancer-relevant voltage-gated potassium channel (hEAG1).

Electrophysiological Characterization of Ts6 and Ts7, K+ Channel Toxins Isolated through an Improved Tityus serrulatus Venom Purification Procedure

The improved isolation method provided toxins with high resolution, obtaining pure Ts6 and Ts7 in two chromatographic steps, and the attempt to elucidate the residues important for interacting with each channel and, in the near future, to model a desired drug stands out.



New Binding Site on Common Molecular Scaffold Provides HERG Channel Specificity of Scorpion Toxin BeKm-1* 210

The most critical residues that are important for the binding of BeKm-1 to the human ERG K+ (HERG) channel are located in the α-helix and following loop whereas the “traditional” functional site of other short scorpion toxins is formed by residues from the β-sheet.

Evolutionary trace analysis of scorpion toxins specific for K‐channels

The first complete cDNA sequences of toxins belonging to subfamily 6 are reported and five new members are identified, called α‐KTx 6.6‐6.10.x, suggesting that accelerated evolution in toxin‐coding regions may be associated with the functional diversification of this subfamily.

Solution structure of CnErg1 (Ergtoxin), a HERG specific scorpion toxin

Structure and function of scorpion toxins affecting K+-channels

This chapter reviews current literature dealing with peptides isolated from the venom of scorpions, and a general nomenclature has been proposed to define 9 distinct sub-families of related sequences.

Structural and Functional Role of the Extracellular S5-P Linker in the HERG Potassium Channel

A structural model for the outer vestibule of the HERG channel is proposed, in which the 583–597 segment forms an α-helix, that may make important contribution to the unique C-type inactivation phenotype.

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.

Three-dimensional structure of ectatomin from Ectatomma tuberculatum ant venom

Two-dimensional 1H NMR techniques were used to determine the spatial structure of ectatomin, a toxin from the venom of the ant Ectatomma tuberculatum, and structures were refined by unrestrained energy minimization using the CHARMm program.

Mapping the Binding Site of a Humanether-a-go-go-related Gene-specific Peptide Toxin (ErgTx) to the Channel's Outer Vestibule*

This study proposes that the long S5-P linker of the HERG channel forms an amphipathic α-helix that, together with the P-S6 linker, forms a hydrophobic ErgTx binding site, which paves the way for future mutant cycle analysis of interacting residues in the Ergtx·HERG complex, which will yield information about the topology of HERG's outer vestibule.