Issues

JGP study reveals how interactions with pore-helix residues control filter inactivation in the prokaryotic potassium channel MthK.

Patch-clamp technique is a powerful method for studying mitochondrial ion transport in real time and under native conditions. This article discusses the limitations of different methodologies, advent of mitoplast patch-clamp technique, and how it presents an exciting opportunity for exploring the molecular physiology of mitochondrial ion transporters.

Retrospective on gating currents from their first recording in 1973 to the present day and their contribution to understanding channel gating.

Kopec et al. show that filter gating in the MthK potassium channel and the pore-helix mutant V55E is associated with widening of the selectivity filter and is modulated by specific interactions between filter and pore-helix residues.

Sodium channels are organized in multiple pools with distinct biophysical properties and subcellular localization, but the role of these subpopulations is not well understood. Computational modeling predicts that intercalated disk-localized sodium channels with shifted steady-state activation and inactivation voltage dependence promote faster cardiac conduction.

The urea transporter UT-B in human red blood cells has been claimed to transport water too. In this study, Brahm et al. show donor variation in urea but not water transport, and a different inhibition pattern for urea and water transport. The authors contest a common pathway for both solutes.

Dantrolene, an inhibitor of the cardiac calcium release channel (RyR2), is a lead compound for stabilizing overactive RyR2 in heart failure. We find that dantrolene inhibition requires RyR2 association with FKBP12.6, which in turn depends on RyR2 phosphorylation at S2808.