Ion Selectivity and Permeation in a Potassium Ion Transporter

Ion permeation and selectivity in ClC-type chloride channels.

Voltage-gated anion channels are present in almost every living cell and have many physiological functions. Recently, a novel gene family encoding voltage-gated chloride channels, the ClC family, was identified. The knowledge of primary amino acid sequences has allowed for the study of these anion channels in heterologous expression systems and made possible the combination of site-directed mut...

Ion binding and permeation at the GABA transporter GAT1.

This study addresses the binding of ions and the permeation of substrates during function of the GABA transporter GAT1. GAT1 was expressed in Xenopus oocytes and studied electrophysiologically as well as with [3H]GABA flux; GAT1 was also expressed in mammalian cells and studied with [3H]GABA and [3H]tiagabine binding. Voltage jumps, Na+ and Cl- concentration jumps, and exposure to high-affinity...

Molecular Simulations of Ion Permeation in Potassium Channels

specific steps in voltage-activation path of an ion channel are altered by a potent allosteric inhibitor. The Kþ channel peptide inhibitor guangxitoxin-1E (GxTX) is partial inverse agonist of the voltage gated potassium channel subtype Kv2.1 from rat. At saturating concentrations of GxTX, Kv2.1 requires higher voltages to activate. The GxTX modulated conductance requires more voltage to activat...

Ion permeation through neuronal nAChR ion channel

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...

Perspectives on Ion Permeation