SUMO modification regulates inactivation of the voltage-gated potassium channel Kv1.5.

Redox-sensitive sulfenic acid modification regulates surface expression of the cardiovascular voltage-gated potassium channel Kv1.5.

RATIONALE Kv1.5 (KCNA5) is expressed in the heart, where it underlies the I(Kur) current that controls atrial repolarization, and in the pulmonary vasculature, where it regulates vessel contractility in response to changes in oxygen tension. Atrial fibrillation and hypoxic pulmonary hypertension are characterized by downregulation of Kv1.5 protein expression, as well as with oxidative stress. F...

Differential sensitivity of voltage-gated potassium channels Kv1.5 and Kv1.2 to acidic pH and molecular identification of pH sensor.

Kv1.2 and Kv1.5 are two subtypes of voltage-gated potassium channels expressed in heart that are thought to contribute to phase 1 (ITO) and phase 3 (IK) components of cardiac action potential repolarization. Although the effect of decreased pH in prolonging cardiac action potentials is well documented, the molecular target of acidification has not previously been determined. We expressed Kv1.2 ...

Cellular Biology Redox-Sensitive Sulfenic Acid Modification Regulates Surface Expression of the Cardiovascular Voltage-Gated Potassium Channel Kv1.5

Phosphorylation-dependent and phosphorylation-independent modes of modulation of shaker family voltage-gated potassium channels by SRC family protein tyrosine kinases.

Modulation of voltage-gated potassium (Kv) channels by protein phosphorylation plays an essential role in the regulation of the membrane properties of cells. Protein-protein binding domains, such as Src homology 3 (SH3) domains, direct ion channel modulation by coupling the channels with intracellular signaling enzymes. The conventional view is that protein kinase binding to ion channels leads ...

Effects of L-type Calcium Channel Antagonists Verapamil and Diltiazem on fKv1.4ΔN Currents in Xenopus oocytes

The goal of this study was to determine the effects of the L-type calcium channel blockers verapamil and diltiazem on the currents of voltage-gated potassium channel (fKv1.4ΔN), an N-terminal-deleted mutant of the ferret Kv1.4 potassium channel. Measurements were made using a two electrode voltage clamp technique with channels expressed stably in Xenopus oocytes. The fKv1.4ΔN currents displayed...