Gating movements and ion permeation in HCN4 pacemaker channels

Gating and Permeation in Ion Channels

Structural basis of ion permeation gating in Slo2.1 K+ channels

The activation gate of ion channels controls the transmembrane flux of permeant ions. In voltage-gated K(+) channels, the aperture formed by the S6 bundle crossing can widen to open or narrow to close the ion permeation pathway, whereas the selectivity filter gates ion flux in cyclic-nucleotide gated (CNG) and Slo1 channels. Here we explore the structural basis of the activation gate for Slo2.1...

Tools for channels: moving towards molecular calculations of gating and permeation in ion channel biophysics.

Recent X-ray structures of voltage gated potassium channels provide an exciting opportunity to connect molecular structures with measured biological function. Two of the most important connections for these channels are: first, to the molecular basis behind selectivity and the associated free energy profile underlying ionic current flow and, second, to a true molecular understanding of the larg...

Biophysics Voltage gating and permeation in a gap junction hemichannel ( connexins / intercellular communication / ion channels / permeability /

Gap junction channels are formed by members of the connexin gene family and mediate direct intercellular communication through linked hemichannels (connexons) from each oftwo adjacent cells. While for most connexins, the hemichannels appear to require an apposing hemichannel to open, macroscopic currents obtained fromXenopus oocytes expressing rat Cx46 suggested that some hemichannels can be re...

Orai1 Mutations Alter Ion Permeation and Ca2+-dependent Fast Inactivation of CRAC Channels: Evidence for Coupling of Permeation and Gating

Ca(2+) entry through store-operated Ca(2+) release-activated Ca(2+) (CRAC) channels is an essential trigger for lymphocyte activation and proliferation. The recent identification of Orai1 as a key CRAC channel pore subunit paves the way for understanding the molecular basis of Ca(2+) selectivity, ion permeation, and regulation of CRAC channels. Previous Orai1 mutagenesis studies have indicated ...