Abstract
Aim:
To gain insight into the interaction between the Charybdotoxin (ChTX) and BK channels.
Methods:
Site-directed mutagenesis was used to make two mutants: mSlo1-F266L and mSlo1-F266A. The two mutants were then expressed in Xenopus oocytes and their effects were tested on ChTX by electrophysiology experiments.
Results:
We demonstrate an equilibrium dissociation constant Kd= 3.1-4.2 nmol/L for both the mutants mSlo 1-F266L and mSlo 1-F266 A similar to that of the wild-type mSlo1 Kd=3.9 nmol/L.
Conclusion:
The residue Phe266 does not play a crucial role in binding to ChTX, which is opposed to the result arising from the simulation of peptide-channel interaction.
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Project supported by Grants from the National Natural Science Foundation of China (30470449).
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Yao, J., Li, H., Gan, Gl. et al. Residue Phe266 in S5-S6 loop is not critical for Charybdotoxin binding to Ca2+-activated K+ (mSlo1) channels. Acta Pharmacol Sin 27, 945–949 (2006). https://doi.org/10.1111/j.1745-7254.2006.00385.x
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DOI: https://doi.org/10.1111/j.1745-7254.2006.00385.x