How Batrachotoxin Modifies the Sodium Channel Permeation Pathway: Computer Modeling and Site-Directed Mutagenesis

@article{Wang2006HowBM,
  title={How Batrachotoxin Modifies the Sodium Channel Permeation Pathway: Computer Modeling and Site-Directed Mutagenesis},
  author={Sho-Ya Wang and Jane Mitchell and Denis B. Tikhonov and Boris S. Zhorov and Ging Kuo Wang},
  journal={Molecular Pharmacology},
  year={2006},
  volume={69},
  pages={788 - 795}
}
A structural model of the rNav1.4 Na+ channel with batrachotoxin (BTX) bound within the inner cavity suggested that the BTX pyrrole moiety is located between a lysine residue at the DEKA selectivity filter (Lys1237) and an adjacent phenylalanine residue (Phe1236). We tested this pyrrole-binding model by site-directed mutagenesis of Phe1236 at D3/P-loop with 11 amino acids. Mutants F1236D and F1236E expressed poorly, whereas nine other mutants either expressed robust Na+ currents, like the wild… 
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TLDR
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TLDR
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