A single point mutation confers tetrodotoxin and saxitoxin insensitivity on the sodium channel II

Abstract

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.