Separation of P/C- and U-type inactivation pathways in Kv1.5 potassium channels.

P/C-type inactivation of Kv channels is thought to involve conformational changes in the outer pore of the channel, culminating in a partial constriction of the selectivity filter. Recent studies have identified a number of phenotypic differences in the inactivation properties of different Kv channels, including different sensitivities to elevation of extracellular K+ concentration, and different state dependencies of inactivation. We have demonstrated that an alternatively spliced short form of Kv1.

Increased focal Kv4.2 channel expression at the plasma membrane is the result of actin depolymerization.

Voltage-dependent potassium channel trafficking and localization are regulated by proteins of the cytoskeleton, but the mechanisms by which these occur are still unclear. Using human embryonic kidney (HEK) cells as a heterologous expression system, we tested the role of the actin cytoskeleton in modulating the function of Kv4.2 channels.

Amino-terminal determinants of U-type inactivation of voltage-gated K+ channels.

The T1 domain is a cytosolic NH2-terminal domain present in all Kv (voltage-dependent potassium) channels, and is highly conserved between Kv channel subfamilies. Our characterization of a truncated form of Kv1.5 (Kv1.