Disulfide locking a sodium channel voltage sensor reveals ion pair formation during activation
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چکیده
منابع مشابه
Disulfide locking a sodium channel voltage sensor reveals ion pair formation during activation.
The S4 transmembrane segments of voltage-gated ion channels move outward on depolarization, initiating a conformational change that opens the pore, but the mechanism of S4 movement is unresolved. One structural model predicts sequential formation of ion pairs between the S4 gating charges and negative charges in neighboring S2 and S3 transmembrane segments during gating. Here, we show that pair...
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Electrical signaling in biology depends upon a unique electromechanical transduction process mediated by the S4 segments of voltage-gated ion channels. These transmembrane segments are driven outward by the force of the electric field on positively charged amino acid residues termed "gating charges," which are positioned at three-residue intervals in the S4 transmembrane segment, and this movem...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2008
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0806486105