Multiple cationic residues of anthopleurin B that determine high affinity and channel isoform discrimination.

@article{Khera1995MultipleCR,
  title={Multiple cationic residues of anthopleurin B that determine high affinity and channel isoform discrimination.},
  author={Paramjit K. Khera and G. Richard Benzinger and Gregory M. Lipkind and Chester Lee Drum and Dorothy A. Hanck and Kenneth M. Blumenthal},
  journal={Biochemistry},
  year={1995},
  volume={34 27},
  pages={
          8533-41
        }
}
Site 3 sea anemone toxins modify inactivation of mammalian voltage-gated Na channels. One variant, anthopleurin A (ApA), effectively selects for cardiac over neuronal mammalian isoforms while another, anthopleurin B (ApB), which differs in 7 of 49 amino acids, modifies both cardiac and neuronal channels with high and approximately equal affinity. Previous investigations have suggested an important role for cationic residues in determination of toxin activity, and our single-site mutagenesis… 
Leucine 18, a Hydrophobic Residue Essential for High Affinity Binding of Anthopleurin B to the Voltage-sensitive Sodium Channel (*)
TLDR
The results indicate that Leu-18 is the most significant single contributor to the high affinity of Anthopleurin B identified to date and broadened the emphasis from the basic residues to include the crucial role of hydrophobic residues in toxin-receptor interactions.
A Specific Interaction between the Cardiac Sodium Channel and Site-3 Toxin Anthopleurin B*
The polypeptide neurotoxin anthopleurin B (ApB) isolated from the venom of the sea anemone Anthopleura xanthogrammica is one of a family of toxins that bind to the extracellular face of
Sea anemone toxins affecting potassium channels.
TLDR
Sea anemones have proven to be a rich source of pharmacological tools, and some of the SAK toxins are now useful drugs for the diagnosis and treatment of autoimmune diseases.
Peptide Toxins in Sea Anemones: Structural and Functional Aspects
TLDR
The following peptide toxins are functionally unique among the known sodium or potassium channel toxins: APETx2, which inhibits acid-sensing ion channels in sensory neurons; BDS-I and II, which show selectivity for Kv3.4 channels; andAPETx1, which inhibit human ether-a-go- go-related gene potassium channels.
Molecular Determinants of High Affinity Binding of α-Scorpion Toxin and Sea Anemone Toxin in the S3-S4 Extracellular Loop in Domain IV of the Na+ Channel α Subunit*
TLDR
Results indicate that nonidentical amino acids of the IVS3-S4 loop participate in α-scorpion toxin and sea anemone toxin binding to overlapping sites and that neighboring amino acid residues in theIVS3 segment contribute to the difference inα-sc Scorpion toxin binding affinity between cardiac and neuronal Na+ channels.
Sea anemone toxins affecting voltage-gated sodium channels--molecular and evolutionary features.
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