A model of the nicotinic acetylcholine receptor transmembrane region has been constructed which may represent the channel in its open-state. The positions of helices flanking the ion channel match those observed by electron microscopy and previously reported by others. Residues labelled, mutated or by other means known to have a strong influence on ion flux are each accessible from the lumen of...

Alzheimer’s dementia is related to loss of inter-neuron communication by nicotinic acetylcholine receptors (nAChR) at post synaptic neurons, and successful therapy approaches rely e.g. on modulations of response signals initiated by ion flux through the receptor integrated ion channel. We have evaluated Umbrella Sampling (US) and Steered Molecular Dynamics (SMD) pulling for calculation of the p...

Propofol is multiple influences on organism function that could affect gene expressions of ion channels, cause arhythmia, impair brain cognitive functions, inhibit energy metabolism and increase hypoxic tolerance. To evaluate whether these phenomena might still exist in persistent low concentration of propofol exposure. We investigated changes in the mRNA levels of Daphnia 120 ion channel genes...

A new atmospheric pressure ionization mass spectrometer (API-MS) interface has been developed to allow the control of ion transmission through the first vacuum stage of the mass spectrometer. The described interface uses a dual-heated capillary and a dual-inlet ion funnel design. Two electrosprays, aligned with the dual-capillary inlet, are used to introduce ions from different solutions indepe...

The saying " use poison as an antidote to poison " has long been considered the spirit of traditional Chinese medicine and herbalism since Ming Dynasty and has indicated the medical values of toxins arising from venomous animals, plants, microbes, or synthetic chemicals. A well-known physician Sir P. M. Latham (1789–1875) once defined the relationship between poisons and medicines as " oftentim...

This is a golden age for ion channels: a time when chemistry, molecular biology, and electrophysiology have come together with structural biology to provide glimpses into some truly amazing membrane proteins. And yet, as usual, the answers yield more questions. Is a new structure the structure of an open channel or of a closed one? How does the voltage sensor actually move? Though providing ama...

The opening rate of voltage-gated potassium ion channels exhibits a characteristic knee-like turnover where the common exponential voltage dependence changes suddenly into a linear one. An explanation of this puzzling crossover is put forward in terms of a stochastic first passage time analysis. The theory predicts that the exponential voltage dependence correlates with the exponential distribu...

Chloride intracellular Channel 1 (CLIC1) is a metamorphic protein that changes from a soluble cytoplasmic protein into a transmembrane protein. Once inserted into membranes, CLIC1 multimerises and is able to form chloride selective ion channels. Whilst CLIC1 behaves as an ion channel both in cells and in artificial lipid bilayers, its structure in the soluble form has led to some uncertainty as...

The coupling of ion and water flow through membrane channels is under dispute. Among all human aquaporins only aquaporin-6 exhibits ion channel activity. Whether aquaporin-6 functions also as a water channel cannot yet be determined with confidence. Similarly, a comparison of single-channel water permeabilities from ion channels and aquaporins suggests that ion channels may play a secondary rol...