The receptor for tetrodotoxin and saxitoxin. A structural hypothesis
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منابع مشابه
The receptor for tetrodotoxin and saxitoxin. A structural hypothesis.
Tetrodotoxin (TTX) and saxitoxin (STX) block sodium channels of nerve and muscle membranes at nanomolar concentrations (2, 7). The structure of TTX is known (Fig. 1), and a new structure of STX (Fig. 2) has just been determined by X-ray crystallography (13). This note describes a hypothesis for the toxin binding site based on the suggestions of several laboratories and inspired by the new STX s...
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Chiriquitoxin (CqTX) from the Costa Rican frog Atelopus chiriquensis differs from tetrodoxin (TTX) only in that a glycine residue replaces a methylene hydrogen of the C-11 hydroxymethyl function. On the voltage-clamped frog skeletal muscle fiber, in addition to blocking the sodium channel and unrelated to such an action, CqTX also slows the activation of the fast potassium current in approximat...
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Purification and characterization of Na+ channel protein from mammalian ventricular myocytes has heretofore been complicated by the low concentration of Na+ channels and by the finding that mammalian ventricles contain both tetrodotoxin (TTX)-sensitive channels (TSC), with high affinity for saxitoxin (STX), and TTX-insensitive channels (TIC), with low affinity for STX. Most (perhaps all) of the...
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A single point mutation of the rat sodium channel II reduces its sensitivity to tetrodotoxin and saxitoxin by more than three orders of magnitude. The mutation replaces glutamic acid 387 with a glutamine and has only slight effects on the macroscopic current properties, as measured under voltage-clamp in Xenopus oocytes injected with the corresponding cDNA-derived mRNA.
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ژورنال
عنوان ژورنال: Biophysical Journal
سال: 1975
ISSN: 0006-3495
DOI: 10.1016/s0006-3495(75)85842-5